Poster presentation

Division of Cardiothoracic Surgery, Department of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR

Aim: A 60-year-old gentleman presented with respiratory failure, requiring emergency rigid bronchoscopy for tracheal stenting. Intra-operatively found an obstructing mass 1 cm above carina, and histology confirmed adenoid cystic carcinoma. Elective VATS tracheal resection with venovenous ECMO support was performed after multidisciplinary conference with anaesthesiologists and perfusionists. Right anterolateral thoracotomy with single-rib partial resection enabled mobilization and resection of 4 cm segment of trachea with negative margins on frozen section. Primary end-to-end anastomosis was performed and reinforced with an intercostal flap. His recovery was uneventful and was discharged on post-operative day 7. This report aimed to describe current practices and review latest literature on intrathoracic tracheal resection.

Methods: A systematic review was conducted on Pubmed and Cochrane databases according to PRISMA 2020 guidelines using keywords: (‘tracheal’) AND (‘resection’) AND (‘minimally-invasive’ OR ‘thoracoscopic’ OR ‘video-assisted’ OR ‘robotic’ OR ‘uniportal’ OR ‘single port’).

Results: Fifteen case reports and two case series encompassing 52 patients were analysed. Forty-three patients (82.7%) received VATS and nine patients (17.3%) RATS. Two cases (3.8%) had ECMO support to avoid intra-field intubation. One centre published two case series and one case report totalling 24 patients (46.2%) describing non-intubated spontaneous ventilation. This technique was associated with shorter OT duration but higher EtCO2 levels. Only one case (1.9%) had severe complications- chylothorax requiring surgical re-intervention.

Conclusions: Intrathoracic tracheal resection can be done via open, VATS, and RATS. Diligent pre-operative planning should be performed in a multidisciplinary setting. Airway protection (intubated vs. non-intubated), ventilation (conventional vs. spontaneous) and oxygenation (with ECMO vs. without) are key safety considerations.

Department of Surgery, Queen Elizabeth Hospital, Hong Kong SAR

Aim: This is a case report to assess intravascular ultrasound (IVUS) use in thoracic endovascular aortic repair (TEVAR) and its role in reducing iodinated contrast load for patients with renal impairment.

Method: A 79-year-old man with chronic renal impairment underwent zone II TEVAR in 2019 for a 6.9 cm descending thoracic aortic aneurysm. Post-op CT was unremarkable until 2024, where a new ulcer-like projection arose just distal to the distal landing zone, suspicious of a stent graft induced new entry tear (SINE). Distal extension TEVAR was performed to cover this SINE. IVUS was used for the following steps: (1) true lumen sizing; (2) branch vessel positioning; (3) confirmation of post-deployment stent expansion.

Results: Celiac artery was identified 2 cm distal to the previous TEVAR stent. A custom made stent based on IVUS findings was deployed with the following dimensions: proximal 28 mm, distal 24 mm, total length 151 mm. After stent deployment, IVUS showed: (1) absence of colour flow signal outside the stent; (2) celiac artery colour flow. This correlated with on table completion angiography findings of (1) no endoleak (2) patent celiac artery. Fluoroscopy with iodinated contrast was used a total of two times in the surgery. The patient's post-op renal function was similar to baseline.

Conclusion: Intra-op use of IVUS was able to: (1) predict size of appropriate prosthesis; (2) confirm branch vessel position; (3) confirm post-deployment resolution of SINE, and; (4) ascertain absence of endoleak. As more operators become familiar with IVUS, it may prove to be a useful adjunct in TEVAR.

Department of Surgery, Tuen Mun Hospital, Hong Kong SAR

Aim: This program aims to (1) provide prophylactic measures to prevent high output ileostomy; (2) early detect high output patients with potential risk of AKI.

Methods: Patients with loop ileostomy after elective rectal cancer surgery were recruited from August 2019 to December 2023. Multidisciplinary approach were adopted to provide stoma output monitoring education, dietary advice and prophylactic medications to avoid high stomal output and subsequent dehydration. Patients' demographic data, neoadjuvant chemoradiotherapy, pre-existing diabetes, renal function tests (preoperative, on discharge, on first follow-up), regular use of loperamide and re-admission were recorded. The primary outcome was incidence of AKI (≥1.5 times of baseline creatinine). Secondary outcomes included unplanned re-admission and ICU admission.

Results: 175 patients (129 male & 46 female) were followed prospectively. The mean age was 64.3 years. 53 patients received neoadjuvant chemoradiotherapy and 28 patients had pre-existing diabetes. 6 (3.4%) patients were readmitted within 1 month due to high output stoma (>1 L per day). 2 (1.1%) were unplanned readmission via the emergency department, while the others were identified during scheduled blood monitoring or follow-up. 3 (1.7%) of them had AKI but none of them required ICU admission. 16 patients required regular loperamide upon discharge for high output ileostomy, and 15 of them eventually had normal stomal output with normal renal function on follow-up. There were no association with AKI and potential risk factors including diabetes, use of metformin, pre-existing renal impairment or neoadjuvant chemoradiotherapy.

Conclusions: High output ileostomy program is effective in minimizing AKI and readmission for high output stoma.

Division of Endocrine Surgery, Department of Surgery, Alice Ho Miu Ling Nethersole Hospital, Hong Kong SAR; Division of Endocrine Surgery, Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong SAR

Aim: Post-operative ICU support is regarded as mandatory for the concerns of hemodynamic instability and hypoglycemia following resection of pheochromocytoma/paraganglioma. With improved anaesthetic techniques and escalating cost of ICU occupancy, such practice has been increasingly challenged. This study aims to evaluate if post-operative ICU is mandatory for every patient following resection of catecholamine-secreting tumour and to identify risk factors predicting the need of post-operative ICU care.

Methods: This is a single-center retrospective cohort study of consecutive adult patients undergoing resection of pheochromocytomas/paragangliomas between January 2013 and December 2022. Baseline characteristics, pre-operative variables, intra-operative/post-operative hemodynamic and other outcomes were collected and analysed by logistic regression.

Results: In the 10-year study period, 45 patients (female, n = 27, 60%) with mean age of 49.8 ± 14.7 years underwent resection of pheochromocytomas/paragangliomas. Thirty-two (71.1%) patients underwent laparoscopic resection. All patients (100%) were managed in ICU post-operatively with a mean length of stay of 27.4 ± 17.4 h. In ICU, 24 patients (53.3%) did not require any pharmacological or organ-specific interventions. Up to 19 (42.2%) patients were discharged to general ward within 24 h of ICU stay. In univariate analysis, large tumour size (>4 cm) (OR 4.17; CI 1.17–14.6; p = .026) and open approach (OR = 6.36; CI 1.45–28.02; p = .014) were associated with increased risk of requiring intervention in ICU.

Conclusions: Post-operative ICU care was not necessary in over 50% of patients undergoing resection of catecholamine- secreting tumours. Patients with small tumour size (≤4 cm) and laparoscopic resection might be selected for surgery without post- operative ICU support.

Department of Surgery, North District Hospital, Hong Kong SAR

Aim: This study aims to review the clinical features, diagnostic approach, treatment options as well as the course of breast fibromatosis based on our institutional experience.

Methods: This is a single-center retrospective cohort study of consecutive adult patients with pathological diagnosis of breast fibromatosis between March 2013 and March 2024. Baseline characteristics, imaging modality, previous pathology, treatment options and recurrence were collected.

Results: Total five patients (female, n = 5, 100%) with mean age of 57.4 ± 22.5 years were included. All of them had ultrasound breasts and mammography as initial imaging modality. Most of them (n = 4, 80%) required further excisional or repeated core biopsy to reach the diagnosis of fibromatosis. Two of them (40%) with previous pathology showing fat necrosis while another two (40%) showing spindle cell lesion/proliferation. Only one patient (20%) had no identifiable previous trauma or risk factor. Most patients (n = 3, 60%) underwent surgical treatment and one of them (20%) was given post-operative radiotherapy. Other treatment options included systemic treatment with tamoxifen and sulindac (n = 1, 20%) and observation (n = 1, 20%). Only one of the patients underwent surgical excision suffered from recurrence.

Conclusions: Although rare, fibromatosis of breast should remain a differential diagnosis while we encounter suspicious breast mass with non-diagnostic pathology, especially in patients with previous trauma/surgery and presence of fat necrosis or spindle cells in the tissue sampling. Multidisciplinary discussion and personalized management for each patient is recommended.

Division of Upper Gastrointestinal and Metabolic Surgery, Department of Surgery, Alice Ho Miu Ling Nethersole Hospital, Hong Kong SAR; Division of Upper Gastrointestinal and Metabolic Surgery, Department of Surgery, Prince of Wales Hospital, Hong Kong SAR

Background: While the latest American Thyroid Associations guidelines suggested against the need of thyroxine suppression for low-risk differentiated thyroid cancer (DTC) after hemithyroidectomy, some patients do require thyroxine supplementation to achieve the recommended thyroid stimulating hormone (TSH) target of 0.5–2.0 mU/L. This study aims to identify factors predicting the need of thyroxine supplementation in this group of patients.

Methods: This was a retrospective cohort study of consecutive low-risk DTC patients who received hemithyroidectomy between January 2016 and December 2022. Multivariate analysis was conducted to evaluate for preoperative variables predicting failed maintenance of TSH ≤2.0 mU/L without thyroxine.

Results: In the study period, 691 patients received hemithyroidectomy, of which 105 patients (female, n = 86, 81.9%) with mean age of 52.2 ± 13.9 years were low risk DTC. In a mean follow-up of 34.7 ± 24.9 months, 55 (52.4%) patients failed to maintain TSH ≤2 mU/L without thyroxine. Their median peak TSH level was 2.5 mU/L (IQR 1.9–3.5 mU/L). In logistic regression analysis, both lymphocytic thyroiditis on histopathology (p < .02, OR = 7.6, 95% C.I. 1.5–39.4) and preoperative TSH >2.0 mU/L (p < .001, OR = 5.5, 95% C.I. 2.5–11.8) were independent factors predicting failure to maintain TSH ≤2 mU/L without thyroxine. There was no significant association with age, gender, body-mass-index, preoperative T4 level, preoperative sonographic parenchymal disease, and preoperative use of steroids.

Conclusions: Although thyroxine supplementation is theoretically unnecessary for low risk DTC following hemithyroidectomy, half of the patients still require thyroxine supplement to maintain optimal TSH target. Patients with pre-existing thyroiditis and preoperative TSH >2.0 mU/L should be counselled thoroughly with regular postoperative TSH monitoring and liberal thyroxine supplementation.

Division of Colorectal Surgery, Department of Surgery, Prince of Wales Hospital, Hong Kong SAR

Background: Colorectal surgery is associated with higher risk of postoperative venous thromboembolism (VTE). In this study, we hope to report the local incidence of VTE in patients who had underwent major colorectal surgeries, and to investigate risk factors and outcomes in this group of patients.

Methods: This is a retrospective cohort study using data from a prospectively collected single centred database between August 2018 and August 2023. Consecutive patients who were 18 years old or above who underwent major colorectal surgeries in Prince of Wales Hospital for colorectal pathologies were included in the analysis.

Results: In the study period, 1510 patients received major colorectal surgeries, of which 128 patients were excluded and 1382 patients were included in this study. 9 patients (0.7%) developed pulmonary embolism, and 4 patients (0.3%) developed deep vein thrombosis. The overall incidence of VTE was 0.94%. There was no 20-day mortality in patients who developed VTE, but they had a higher incidence of prolonged hospital stay of more than 20 days (p = .003, OR = 18, 95% C.l 4.9–68.4). No association was found between VTE and sex, comorbidities, duration and types of surgery, elective or emergency surgery, presence of malignancy or inflammatory bowel disease.

Conclusions: Local incidence of VTE post major colorectal surgeries is low at 0.94%, but it is associated with longer hospital stay. Further studies are needed to identify the risk factors for VTE for development of a validated risk model and subsequent protocol for VTE prophylaxis in local patients undergoing major colorectal surgeries.

Department of Surgery, New Territories West Cluster, Hospital Authority, Hong Kong SAR

Aim: Inverted colonic diverticula (ICD) are rare colonoscopy findings and occur in approximately 0.7% of people. This could possibly be under reporting due to the lack of awareness and limited cases presented as case reports only. This article aims to evaluate the incidence from a personal series prospective, features of inverted colonic diverticulum and possible methods that can help diagnose ICD.

Methods: Patients with colonoscopy findings of ICD were reviewed from 2015 to 2024 in the department of surgery, New Territories West Cluster, Hospital Authority, HKSAR.

Results: Total 2604 colonoscopies were performed by a single endoscopist in this time period and 5 patients were diagnosed with ICD (0.19%). The mean age of the patients was 64.2 years old (ranging from 56 years old to 71 years old), with 3/2 male/female ratio. All (5/5) of the ICD were in the area of multiple colonic diverticula, and 60% (3/5) were located in the right-hemi colon. The features of ICD include elevated sessile ‘bubble wrap like’ appearance with fine concentric folds surrounding the lesion which enhanced with Methylene Blue. Gentle pressure with biopsy forceps can revert ICDs into typical diverticula. ICD cases were also reviewed by using Artificial Intelligence (AI) endoscopy system, sometimes failures in differentiating ICDs from polyps by AI were still encountered.

Conclusion: ICD is a rare intraluminal lesion that can be misinterpreted as elevated polypoid lesion. Meanwhile endoscopists' experience may still be the most important factor in diagnosing ICD to prevent serious complications from ‘polypectomy’ for misdiagnosed ICDs.

Department of Surgery, Tuen Mun Hospital, Hong Kong SAR

Aim: Palliative stoma is an common surgical option in advanced colorectal cancer with malignant bowel obstruction, perforation, or fistulation. Exploring factors related to mortality would help to guide our clinical management and improve surgical outcomes. To identify factors in predicting the mortality of advanced colorectal cancer after palliative stoma creation.

Methods: In 2019–2022, advanced colorectal cancer patients with palliative stoma done in TMH and POH were reviewed. Data was collected through electronic records.

Results: Mortality within 30 days is 5.4% for SOMIP <10%, 30.4% for SOMIP >10% (p = .003). Mortality within 60 days is 16.2% for SOMIP <10%, 43.5% for SOMIP >10% (p = .01). Mortality within 90 days is 18.9% for SOMIP <10%, 52.2% for SOMIP >10% (p = .003). SOMIP score is associated with mortality within 30, 60 and 90 days (p < .05). ALP level is associated with mortality within 30, 60 and 90 days (p < .05). Functional status is associated with mortality within 30, 60 and 90 days (p < .05). Preoperative ascites within 30 days is associated with mortality within 60 and 90 days (p < .05). ASA physical status and serum albumin level are associated with mortality within 30 days (p < .05).

Conclusions: SOMIP score helps predict mortality within 30, 60 and 90 days for palliative stoma in advanced colorectal cancer. SOMIP score, ALP level, and functional status are associated with mortality within 30, 60 and 90 days. ASA physical status and serum albumin level is associated with mortality within 30 days, whilst preoperative ascites is associated with mortality within 60 and 90 days.

Department of Surgery, Kwong Wah Hospital, Hong Kong SAR

Aim: Intraoperative indocyanine green (ICG) fluorescence imaging has been shown to be an effective tool to assess anastomotic perfusion. The aim of this retrospective review is to evaluate its efficacy in the prevention of anastomotic leakage (AL) after low anterior resection for rectal cancer in a single centre in Hong Kong.

Methods: In this retrospective review, we included 185 consecutive patients who underwent elective surgery with or without the use of intraoperative ICG fluorescence imaging for rectal cancer from January 2016 to March 2024. For patients with the use intraoperative ICG fluorescence imaging, we evaluated if it was necessary to change the intestinal transection line for anastomosis. The demographic data, incidence of anastomotic leakage, post-operative morbidity and mortality on postoperative day 30 were recorded and analysed.

Results: There were 126 male and 59 female patients. Their age ranged from 32 to 86 with a median of 66. 63 patients had ICG fluorescence imaging done and 122 patients did not. The overall AL rate was 8.11%. 11 patients with no ICG fluorescence imaging done and 4 patients with ICG fluorescence imaging had AL. The incidence of AL was not statistically different between the two groups (p = .777). Five patients had change in resection line based on ICG findings and none of them had leakage. One patient died within 30 days postoperatively.

Conclusion: Intraoperative ICG fluorescence imaging does not prevent anastomotic leakage in low anterior resection for rectal cancer in this review.

Department of Surgery, Kwong Wah Hospital, Hong Kong SAR

Aim: Management of pancreatic cysts has evolved from surgeries to a more conservative approach. This study aims to review indications for surgeries for pancreatic cysts.

Methods: Patients with pancreatic cysts who underwent surgeries in Kwong Wah Hospital from January 2000 to June 2024 (N = 23) were included. Their high-risk and worrisome features as defined in Fukuoka guidelines were studied and compared with the final pathologies, complications and mortality. Data was analysed by SPSS Statistics software.

Results: 74% were benign pathologies including benign cysts (30%), intraductal papillary mucinous neoplasms (IPMN) with low grade dysplasia (13%), serous cystadenoma (17%). The remaining 26% included invasive carcinoma (9%), lesions with high malignant potentials like IPMN with intermediate/ high grade dysplasia (9%) and mucinous cystic neoplasms (9%). Comparable proportions of malignant lesions (60%) and benign lesions (56%) had at least one high-risk features. 20% of the malignant lesions had two high-risk features, while none of the benign lesions had two or more. In pancreatic cysts without any high-risk features, 100% of the malignant lesions versus 25% of the benign lesions had two or more worrisome features. 57% had complications of Clavien-Dindo grade II or above and 4% had 30-day mortality.

Conclusion: Many cysts with high risk features turned out to be benign cysts in the surgical pathologies, which should be included during preoperative counselling. Some malignant lesions were observed to have only worrisome features, hence pancreatic cysts with worrisome features are strongly advised for further investigations to identify indications for surgeries.

Department of Surgery, Queen Mary Hospital, Hong Kong SAR

Aim: Increasing incidence of breast cancers among the elderly presents a management challenge due to comorbidities and fragility. This study aims to evaluate the feasibility, safety and tumour ablative rate of percutaneous cryoablation under local anaesthesia in breast cancer patients who are not suitable for standard surgical treatment.

Methods: Patients with histologically-confirmed breast cancer, tumour size ≤3 cm, unifocal lesion without skin involvement and high risk for general anaesthesia were prospectively recruited. Ultrasound-guided percutaneous cryoablation was performed under local anaesthesia.

Results: Seventeen patients (median age: 87 years, range: 79–93) were recruited between January 2023 and July 2024, all with multiple comorbidities. Sixteen (94%) patients had invasive carcinoma, and one had ductal carcinoma in situ. Twelve (71%) patients were clinically T1N0, and 4 were T2N0. Median sonographic tumour diameter was 17.2 mm (range: 8.2–35 mm). Fourteen (82%) patients were oestrogen receptor positive and received primary hormonal treatment. Sixteen (94%) patients underwent successful cryoablation under local anaesthesia, with 13 (76%) requiring sedations. One patient required conversion to general anaesthesia due to significant reflux. Complete ablation was achieved in all with confirmation by ultrasound. Median procedure time was 73.5 min (range: 32–117 min). Median pain score was 1 on a scale of 1–10. Median hospital stay was 1 day. One patient experienced frost injury of the skin, which resolved within a week with conservative management.

Conclusion: Percutaneous cryoablation can be safely performed under local anaesthesia with low morbidity and high tolerability in elderly breast cancer patients, potentially achieving complete tumour ablation. Longer-term oncological outcomes are pending.

Department of Surgery, North District Hospital, Hong Kong SAR

Aim: R0 resection in Whipple's operation remains a challenge to surgeons despite intra-operative frozen section. This study aims to assess whether TMpE and SMA first approach in Whipple's operation for malignant periampullary tumours can improve R0 resection rate while achieving comparable early outcomes.

Method: This is a retrospective cohort study including all patients undergoing Whipple's operation of malignant periampullary tumours in North District Hospital from February 2020 to February 2024. The primary outcome is R0 resection rate.

Results: In this study period, 6 patients had undergone TMpE and SMA first approach and 37 patients had conventional Whipple's. The median ages were 75 years and 64 years respectively (p = .02), and both were male predominant (66.7% vs. 62.2%; p = .83). 16.7% versus 24.3% were pathological stage III to IV disease (p = .68). The R0 resection rate was 100% versus 75.7% (p = .17). The operating time (mean 557.5 ± 40.5 vs. 553.0 ± 90.0 min; p = .52), blood loss (mean 1000 ± 385 mL vs. 978 ± 851 mL; p = .95), clinically significant pancreatic fistula (33.3% vs. 29.7%, p = .86) and chyle leak (16.7% vs. 13.5%, p = .84) were all statistically insignificant. No patients died within 30 days in both groups. The 6 months recurrence (33.3% vs. 32.4%; p = .97) and mortality (16.7% vs. 13.5%; p = .84) were comparable.

Conclusion: Whipple's operation with TMpE and SMA first approach showed a trend towards higher R0 resection rate, albeit not reaching statistical significance. There was no significant difference in other intra-operative and post-operative outcomes. Further study with larger sample size is necessary to evaluate the efficacy of this surgical approach.

Department of Surgery, Queen Mary Hospital, Hong Kong SAR

Aim: To evaluate the peri-operative and long-term outcomes of patients who underwent laparoscopic and open pancreaticoduodenectomy.

Methods: Retrospective review was performed on patients who received laparoscopic pancreaticoduodenectomy, laparoscopic with conversion to open, and open pancreaticoduodenectomy from January 2017 to April 2024. Data was reviewed from the prospectively maintained database for patient demographics, perioperative factors, and survival outcome.

Results: There were 185 patients identified, including 37 who received successful laparoscopic procedure, 12 who underwent conversion to open, and 136 who received open procedure. Indications for surgery included pancreatic adenocarcinoma, intraductal papillary mucinous neoplasm, ampullary adenocarcinoma, pancreatic neuroendocrine tumour, duodenal gastrointestinal stromal tumour, mucinous adenocarcinoma of colorectal origin, low grade dysplasia of common bile duct, and ampullary tubular adenoma. The laparoscopic group had less median blood loss of 300 mL compared to both conversion and open groups, at 1750 and 700 mL respectively (p < .001), and less blood transfusion at 10.8% compared to 75.0% and 36.9% respectively (p < .010). Laparoscopic and conversion groups both had longer median operating times at 528 and 588 min respectively, compared with 330 min for the open group (p < .010). The laparoscopic group had the highest post-operative complication rate of Clavien-Dindo Grade IIIA or above at 40.5% compared to 16.7% for conversion and 19.1% for the open group (p = .028). There was no difference in post-operative pancreatic fistula, post-operative haemorrhage, re-operation, duration of admission, re-admission within 3 months, hospital mortality, or overall survival.

Conclusions: Laparoscopic pancreaticoduodenectomy is associated with superior outcomes in blood loss and transfusion, operating time, and overall survival.

Department of Surgery, Tuen Mun Hospital, Hong Kong SAR

Aim: This study aims to describe the association of preoperative tumour pain (clinical), Ca19.9 (biochemical), positron emission tomography (PET) (radiological) and intraoperative resectability of radiologically resectable pancreatic head adenocarcinoma.

Methods: This retrospective cohort study included all patients with radiologically resectable pancreatic head adenocarcinoma who were arranged elective pancreaticoduodenectomy from January 2019 to September 2023 in a tertiary hospital in Hong Kong. The severity of tumour pain were assessed by Numeric Rating Scale of Pain (1–10) upon admission for surgery. The primary outcome is the association of severity of tumour pain, Ca19.9, PET and the intraoperative resectability of their tumours.

Results: This study included 54 patients in total, 24 of them (44.4%) were noted to have unresectable disease upon surgical exploration either due to unpredicted locally advanced tumour (n = 10, 41.7%) or distant metastases (n = 14, 58.3%). Overall intraoperative resectability was not associated with severity of preoperative tumour pain (p = .698) and level of Ca19.9 (p = .662). Upon subgroup analysis, the severity of pain and level of Ca19.9 were not associated with intraoperative resectability in both groups of patients with locally advanced disease or distant metastasis. The negative predictive value (NPV) of PET in detecting distant metastases was 72.7%. Time from initial imaging to operation was significantly associated with more locally unresectable tumours (p = .003).

Conclusions: For patients with radiologically resectable pancreatic head adenocarcinoma, the severity of preoperative pain and level of Ca19.9 are not useful in predicting final intraoperative resectability. PET may have limitation in detecting distant metastasis preoperatively with the NPV of 72.7%.

Department of Surgery, Princess Margaret Hospital, Hong Kong SAR

Aim: To compare outcomes between bilateral laparoscopic hernia repair and bilateral Lichtenstein surgery under our new multimodal analgesia program.

Methods: This was a 3-year single-center retrospective review of patients with elective bilateral hernia repair. Patient demographics, ASA, waiting time of operation, operative and theatre time, HLOS, post-operative adverse events and recurrence rates were compared.

Results: Total of 73 patients were selected (59 laparoscopic and 14 bilateral LA with ilioinguinal nerve block) for comparison. There was significant difference in age (Laparoscopic 68 + −9 vs. LA 76 + −7, p = .0019) and ASA Classification (2.17 vs. 2.82, p = .00616). Significant shorter waiting time of operation in LA group (136 vs. 299 days) (p = .017).

Significant shorter operative time in laparoscopic group (p = .041) but no significant difference in theatre time (p = .15). No significant difference regarding HLOS (p = .68), readmission rate (p = .73) and post-operative adverse events (p = 1.0). No statistically significant difference regarding inpatient usage of analgesics. Average use of oral Panadol 500 mg tablet was 2.13 + −1.87 vs. 2.57 + −2.87 tablets/day (p = .48) and average use of oral tramadol was 0.068 + −0.31 vs. 0.071 + −0.27 tablets/day (p = .97). The adverse events and complications rates were similar with no significant difference in rates of seroma (p = .48), hematoma (p = .71) and recurrence (p = 1.0).

Conclusions: Patients who underwent bilateral open hernioplasty under our new Open Inguinal Hernioplasty with Multimodal Analgesia by Surgeon Program had a shorter waiting time and a higher ASA grading, but had comparative post-operative pain control, HLOS and complication rates compared to the laparoscopic group. These results suggest that our new program is a safe and effective alternative to laparoscopic bilateral hernioplasty especially in patients with high ASA grading.

Department of Surgery, Princess Margaret Hospital, Hong Kong SAR

Aim: Review outcomes of palliative diversion stoma in MBO patients with metastatic or inoperable gastrointestinal malignancy and identify clinic-pathological predictors for better survival.

Methods: 5 year single center descriptive retrospective review of patients receiving emergency operation with palliative diversion stoma performed. Patients were grouped into four groups according to survival days. Patients' demographics, clinicopathological parameters, survival days and episode death rates reviewed.

Results: 120 patients included, with 78, 31 and 11 patients underwent transverse colostomy, loop ileostomy and sigmoid colostomy respectively. No significant differences in patient's demographics (sex, age, ASA classification, BMI). Survival rate was 89%, 65% and 23% respectively at 1 month, 3 months and 1 year respectively. Median survival rate was 162 days. Albumin, haemoglobin, and ALP levels were significant independent biochemical predictors of improving survival (p = .0000253, p = .0385 and p = .043). ICU and HDU admissions were poor survival prognostic factors (p = .000076). Post-operative chemotherapy and better preoperative mobility were significant positive survival prognostic factors (p = .000124 & p = .019). No significant difference in terms of complications with Clavien-Dino class II or above. No difference in survival between transverse colostomy and loop ileostomy (p = .116).

Conclusions: This retrospective study examined the survival pattern and predictive factors in patients with MBO with underlying gastrointestinal malignancy. Higher albumin and haemoglobin levels and lower ALP levels are significant predictors for improved survival. ICU and HDU stays were significant negative predictors for survival, while better preoperative mobility and post-operative chemotherapy were significant positive predictors for survival. These variables may act as predictive tools to identify high mortality risks patients, and alternative of non-operative treatment may be considered for these patients.

Department of Surgery, Queen Elizabeth Hospital, Hong Kong SAR

Aim: When patients with advanced colorectal cancer develop malignant bowel obstruction as a complication of their disease, palliative defunctioning colostomy, either done via a trephine incision at the site of intended stoma creation or done alongside laparotomy, is often considered. Such a major operation could be a major undertaking in this patient group as they often have a relatively poor prognosis with or without the surgery. Local data has been lacking over which approach to adopt in creating a palliative stoma, as well as which patients could potentially benefit more as longer survivors after surgery. This study aims to identify risk factors associated with early mortality in colorectal tumour patients receiving palliative colostomy.

Methods: This study retrospectively analysed 62 cases in 6 years at a regional surgical center. Statistical analyses were performed using IBM SPSS Statistics version 20.0 (IBM Corporation, Armonk, NY, USA).

Results: Stoma creation alongside laparotomy was found to be associated with a higher 3-month mortality when compared with those cases without laparotomy (p = .042). A lower preoperative albumin level (p = .014) and a higher SOMIP score (p = .005) were shown to predict a higher chance of 3-month mortality as well with statistical significance.

Conclusions: A lower preoperative albumin level and a higher SOMIP score could help predict early mortality in patients with obstructive colorectal cancer undergoing palliative colostomy. These can be taken into consideration to aid decision making in palliative operation. If possible, avoiding unnecessary laparotomy during palliative stoma creation may also lead to better 3-month survival after surgery.

Department of Surgery, Queen Elizabeth Hospital, Hong Kong SAR

Aim: Complex abdominal wall defects, either resulting from tissue loss, burst abdomen, or trauma catastrophes, post significant challenges for closure and reconstruction. Mesh-mediated fascial traction (MMFT) in combination with negative pressure wound therapy (NPWT) is an emerging technique to aid gradual closure of large abdominal wall defects. We here report two cases of MMFT with NPWT in polytrauma with penetrating abdominal injury.

Methods: Case 1: A 61-year-old male sustained a 20 cm lower abdominal wound and small bowel evisceration following a road traffic accident. After trauma laparotomies, MMFT with NPWT was used over 4 tightening sessions, decreasing the fascial defect from 10 × 10 cm to 5 × 5 cm, allowing for fascial closure with sutures. Macerated fascia was reinforced with polytetrafluoroethylene (PTFE) felt. He had reversal of Hartmann's procedure later. At follow-up, no incisional hernia was noted. Case 2: A 25-year-old male with polytrauma, including pelvic fracture, splenic rupture, and colon ischemia. MMFT with NPWT was used over 5 relaparotomies to achieve fascial closure.

Department of Surgery, Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR

Aim: Application of CRP to predict anastomotic leakage (AL) is widely studied in colorectal surgery but not in upper gastrointestinal tract. Studies are limited with no conclusive result. The aim of this study is to investigate the predictive value of CRP for AL in patient with gastric cancer who has undergone curative gastrectomy.

Conclusions: CRP level can be a early predictor with considerable sensitivity and specificity to rule in and rule out anastomotic leakage after elective gastrectomy for gastric cancer.

Department of Surgery, Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR

Aim: The approach to vascular ligation for the resection of rectosigmoid cancer is debatable. Concerns remain that high ligation of the inferior mesenteric artery (IMA) may compromise blood flow to the colonic anastomosis, which may increase complications such as ileus and leakage. On the contrary, low ligation of IMA distal to the left colic artery (LCA) origin may compromise the yield of lymph node dissection. Thus, low ligation of IMA can be performed with high dissection of the lymph nodes at the IMA root. However, the difference in perioperative outcome between high ligation (HL) and low ligation with high dissection (LLHD) remains uncertain. This study aims to compare clinical outcomes of HL and LLHD of IMA in rectosigmoid cancer patients who underwent laparoscopic surgery.

Methods: A retrospective cohort study was conducted to compare the intra-operative blood loss, operation time, length of post-operative hospital stay and anastomotic leakage rate between the HL group and LLHD group.

Results: Both the HL group and LLDH group showed comparable outcomes in terms of blood loss, operation time, length of post-operative hospital stay and anastomotic leakage rate.

Conclusions: LLHD demonstrates no significant advantage over HL in terms of clinical outcome.

Department of Surgery, United Christian Hospital, Hong Kong SAR

Aim: Preoperative assessment of axillary nodal status is important in selecting patients for the appropriate procedure in breast cancer management. Our hospital adopted a new classification system for ultrasound assessment of axillary lymph nodes. This study aims to evaluate its role in axillary management for breast cancer.

Methods: This was a retrospective analysis involving 122 breast cancer patients who received upfront surgical treatment at United Christian Hospital from November 2022 to October 2023. The correlation between preoperative sonographic classification of axillary lymph nodes and the final histological results were evaluated.

Results: Among patients included in the analysis, 41 (33.6%) had axillary lymph node metastasis while 81 (66.4%) had N0 disease. The rates of malignancy, according to the sonographic classification, were as follows: 26.5% for grade I (22/83), 23.1% for grade II (3/13), 57.1% for grade III (4/7), 50.0% for grade IV (3/6), 42.9% for grade V (3/7) and 100% for grade VI (6/6). When the patients were categorized into having normal (type I and II) and suspicious nodal morphology (type III to VI), the sensitivity, specificity, accuracy for the preoperative axillary lymph node classification were 39.0%, 87.7% and 71.3% respectively.

Conclusions: Our findings suggested that sonographic classification of axillary lymph nodes can better stratify risk of nodal metastasis in ultrasound assessment. It was associated with relatively high specificity but rather low sensitivity. FNAC can be skipped especially for grade VI nodal morphology. However, the low sensitivity precluded its role in adequate staging in breast cancer management.

Department of Surgery, Tseung Kwan O Hospital, Hong Kong SAR

Aim: To assess patient satisfaction in relation to the volume reduction rate (VRR) in 3, 6 and 12 months after RFA.

Methods: This is a retrospective, single-centre study evaluating 46 patients who were treated with RFA for 50 benign non-functioning thyroid nodules between March 2021 to June 2023. All patients were followed up at 3, 6 and 12 months with ultrasound done. All patients were asked to fill in a questionnaire with cosmesis score (0–10), compressive symptom score (0–10) and overall satisfaction score (0–10) before and on each follow up after the procedure. Our primary endpoint was to evaluate the mean questionnaire scores and our secondary endpoint was to look at its relationship with the change in mean VRR.

Results: Our results showed that the patient's compressive and cosmetic symptoms improved with every follow up, along with their overall satisfaction. The mean VRR was 59% at 3 months, 66.6% at 6 months and 64.2% at 12 months. However, there were seven missing data for VRR at 12 months interval, compared to three for both 3 and 6 months. This might contribute to the decrease in VRR between 6 and 12 months. Despite the decrease in VRR, the questionnaire scores still showed an overall improvement trend.

Conclusions: RFA is a promising alternative treatment for benign non-functioning thyroid nodules with high patient satisfaction and reduction in patient's compressive and cosmetic score. +53:538:59.

Department of Surgery, Kwong Wah Hospital, Hong Kong SAR

Aim: To evaluate the rate of anastomotic leakage with and without TDT in patients underwent LAR for rectal cancer.

Methods: This is a single-centre, retrospective study evaluating the rate of anastomotic leak with and without TDT in patients who underwent laparoscopic LAR for rectal cancer between February 2011 to September 2022. Patients with tumour distance >10 cm from anal verge, with coloanal anastomosis, end colostomy, handsewn anastomosis, laparoscopic converted open and those who required emergency surgery or stoma creation pre-operatively were excluded from the study. 117 patients were included for analysis.

Results: 6% (7/117) of all patients has anastomotic leakage while TDT group has a lower rate (2.1%, n = 1/47 vs. 8.6%, n = 6/70, p = .240) but not statistically significant. As potential confounding factor, more patients in TDT group received neoadjuvant therapy (61.7% vs. 24.3%, p < .001). Patients with anastomotic leakage showed significantly lower pre-operative albumin level (34 g/L vs. 38 g/L, p = .024) and larger tumour size (4 vs. 2.5 cm, p = .005). After the inclusion of main effect of TDT and its interaction effect with neoadjuvant therapy in the regression model, tumour size was identified as the only significant factor for leading anastomotic leakage (p = .019) via backward approach (AIC = 47.736; Hosmer and Lemeshow Test, p = .913 > .05) and the adjusted OR was 1.74 (95% CI = 1.10–2.75).

Conclusions: This study failed to show a significant reduction in anastomotic leakage rate with the use of TDT. However, larger tumour size was shown to be a risk factor for anastomotic leak.

Department of Surgery, Tuen Mun Hospital, Hong Kong SAR

Aim: Polidocanol (Aethoxysklerol 3%) foam sclerotherapy is an emerging outpatient procedure to treat symptomatic internal haemorrhoids. However, local data is lacking. This study aims to provide preliminary results to evaluate the efficacy and safety of polidocanol foam sclerotherapy in this locality.

Methods: 104 patients with symptomatic internal haemorrhoids from the outpatient clinic of Tuen Mun Hospital were recruited from Oct 2023 to March 2024. 10 patients were excluded due to coexisting anorectal disease, pregnancy or patient refusal. 43 patients underwent injection sclerotherapy with a 1 mL-per-piles regime while 51 patients underwent the 3 mL-per-piles regime. The severity of symptoms were evaluated using the Sodergren score before the procedure as baseline, 1-week and 1-month after the procedure. All adverse events were recorded.

Results: There was overall significant improvement of symptoms upon 1-month follow-up compared with the baseline (3.19 vs. 7.81, p < .001). Complete resolution of symptoms was observed in 28 patients (30%), while improvement of symptoms was observed in 65 patients (69%) in terms of bleeding (0.30 vs. 1.55, p < .001), prolapse (0.73 vs. 1.46, p < .001), itching (0.12 vs. 0.28, p = .02), pain (0.10 vs. 0.50, p < .001) and soiling (0.06 vs. 0.29, p = .006). There was no significant difference in outcome between the 1 mL-per-hemorrhoid group and the 3 mL-per-hemorrhoid group. One adverse event was recorded as one thrombosed hemorrhoid was observed upon 1-month follow-up.

Conclusion: Polidocanol foam sclerotherapy is a safe procedure that provides promising short term outcome to relieve symptoms of haemorrhoids. Further study is required to evaluate its long term outcome in our locality.

Department of Surgery, United Christian Hospital, Hong Kong SAR

Background: Laparoscopic complete mesocolic excision (CME) of the right colon with central vascular ligation (CVL) is still under speculations, mainly because of the technical difficulty and uncertain oncological superiority. Our centre started laparoscopic CME and CVL since December 2023. We retrospectively evaluated the safety and oncological outcomes of the procedures.

Materials and Methods: Prospectively collected data of patients who underwent CME between December 2023 and June 2024 were retrospectively analysed. Patients who underwent conventional right hemicolectomy between January 2023 and January 2024 were used for the comparison. The primary outcome of the study was total lymph nodes harvested. Secondary outcomes were intra-operative and post-operative complications, operative time and length of stay.

Results: The study included 36 patients (12 in the CME group and 24 in the non-CME group). Lymph node yield was higher (21 vs. 18, p < .05) and operative time was significantly longer in CME group (283 vs. 196 min, p < .05). Length of hospital stay was longer with CME (10 vs. 7 days, p = .052). There were no significant differences in R0 resection rate, intra-operative/post-operative complications and readmission rates.

Conclusions: In our early experience, laparoscopic CME with CVL is feasible and safe, provides significantly higher lymph nodes harvest without increasing in complications or morbidities, although it is currently associated with a longer operation time and length of stay. Further study is needed to evaluate the mid/long term survival and recurrence.

Department of Surgery, United Christian Hospital, Hong Kong SAR

Background: Traditional wound closure techniques include skin sutures and stapling with metal clips. Substantial wound infection rate was observed in traditional wound closure using sutures and clips, especially near stoma sites. Sterile, liquid topical tissue adhesive composed of cyanoacrylate as main ingredient. Cyanoacrylate has barrier property against microorganisms' infiltration, allows water-dependent activities (eg showering), does not require removal and has a fast application. We retrospectively evaluated the feasibility and safety of skin adhesives after wound closure in laparoscopic colorectal surgery.

Materials and Methods: 79 patients who underwent laparoscopic colorectal surgery with skin adhesives as wound closure technique from December 2023 to June 2024 were retrospectively reviewed. The primary outcome focused on post-operative wound infection rate. Infection rate from November 2022 to October 2023 in laparoscopic colorectal surgery using traditional wound closure method (ie skin stapler) was used for comparison.

Results: The study included 79 patients using glue for wound closure. Wound infection rate was significantly lower in the glue group compared with non-glue group (1.3% vs. 8.0%, p = .042).

Conclusions: In our early experience, tissue adhesive is a feasible and safe method for skin wound closure after laparoscopic colorectal surgery, provides significantly lower wound infection rate. The result enables future study on postoperative pain and cosmetic results using this method.

Department of Surgery, United Christian Hospital, Hong Kong SAR

Background: Laparoscopic surgery has long been the gold standard to colorectal surgery. However operative parts in confined space, acute-angled positions (e.g. splenic flexure) and areas with crucial structures (e.g. lymph node dissection) remain challenging even to experienced surgeons. To overcome the challenges in these aspects, many overseas centres tried to use ARTISENTIAL® instruments by providing advanced articulation to enhance dexterity and accessibility. Results were promising. Our centre was the 1st in Hong Kong to introduce and utilize the ARTISENTIAL® instruments.

Methods: Between December 2023 and June 2024, colorectal cancers patients who underwent laparoscopic resection using ARTISENTIAL® instruments by a single surgeon (who received 3-day training in the use of ARTISENTIAL® in Korea) were evaluated. The perioperative and short-term post-operative data were analysed.

Results: Fifteen patients (11 males/4 females) were included in this study. Median age was 67 years (range 64–86 years). Six with right-sided colonic cancers and nine with left-sided or rectal cancers. The median operative time was 325 min (range 232–401). Median estimated blood loss was 20 mL. There was no conversion to laparotomy. No cases of circumferential resection margin involvement (R0 = 100%). Median length of stay was 12 days. There was no anastomotic leakage.

Conclusions: In our early experience, colorectal surgery with ARTISENTIAL® is feasible and safe. It is easy to learn with comparable resection quality even for surgeons who are new to the tool. This study result serves to enable further use and study of the instruments in the future in order to improve surgical outcomes.

Department of Surgery, Princes of Wales Hospital, Hong Kong SAR

Aim: Spontaneous tumour rupture is a fatal complication of Hepatocellular carcinoma. The surgical and oncological outcomes in ruptured HCC remain contentious. This study aimed to compare survival outcomes of spontaneous-ruptured HCC (srHCC) with that of non-ruptured HCC (nrHCC).

Methods: This study retrospectively reviewed 38 srHCC and 774 nrHCC patients who underwent hepatectomy between 2010 and 2022 at Prince of Wales Hospital, Hong Kong SAR. A 1:2 propensity score matching (PSM) analysis was conducted to compare overall survival (OS) and disease-free survival (DFS) between the two groups.

Results: Before PSM, srHCC patients had significantly lower overall survival (median OS: 28.6 vs. 150.8 months; p < .001) and poorer disease-free survival (median DFS: 6.2 vs. 54.5 months; p < .001) compared to nrHCC patients. After PSM, there were no significant difference in 90-day mortality rate (7.9% vs. 3.9%; p = .396) and overall survival (median OS: 28.6 vs. 46.5 months; p = .46) between srHCC and nrHCC groups. However, disease-free survival rates were lower for srHCC (median DFS: 6.2 vs. 11.7 months; p < .032). Extrahepatic recurrence and peritoneal metastasis were higher in srHCC patients (50% vs. 25%; p = .016 and 18.4% vs. 3.9%; p = .022, respectively). Spontaneous tumour rupture was identified as an independent risk factor for poor DFS in both univariate (HR: 1.591; p = .034) and multivariate analyses (HR: 1.724; p = .037), but not for OS (HR: 1.197; p = .46).

Conclusions: Patients with srHCC have poorer disease-free survival post-hepatectomy compared to those with nrHCC. Spontaneous tumour rupture is an independent risk factor for poor DFS and is associated with a higher incidence of extrahepatic metastasis.

Department of Surgery, Princess Margaret Hospital, Hong Kong SAR

Aim: Open inguinal hernia repair is a commonly performed procedure in general surgery. It can be done under different modes of anaesthesia. The aim of current study is to compare the efficiency and the outcomes of open inguinal hernia repair under local anaesthesia plus ultrasound-guided ilioinguinal nerve block with other modes of anaesthesia.

Methods: It is a retrospective cohort study of elective unilateral open inguinal hernia repair from May 2022 to May 2023 in Princess Margaret Hospital. The medication used for LA and nerve block was standardized. Outcomes included operative time, non-operative time in theatre, length of hospital-stay, inpatient use of analgesics, early adverse events, and recurrence in 6 months.

Results: A total of 104 patients were included. Forty-nine patients underwent LA with USG-guided nerve block, while 59 patients underwent other modes of anaesthesia. The mean operative time (minutes) was similar (61.3 vs. 63.2, p = .673). Mean non-operative time in theatre (31.7 vs. 36.4, p = .021) and the length of hospital stay (days) (1.65 vs. 2.43, p = .008) were shorter in LA group. The rate of analgesics used was significantly lower in LA group [27 (55.1%) vs. 47 (85.5%), p < .001]. There was a lower rate of early post-operative adverse events in LA group [5 (10.2%) vs. 18 (32.7%), p = .006]. There was no significant difference in recurrence rate [2 (4.4%) vs. 1 (2.0%), p = .602].

Conclusions: Open inguinal hernia repair under LA and USG-guided nerve block is more efficient in terms of shorter non-operative time in theatre, shorter hospital-stay, and lower rate of analgesics use.

Department of Surgery, Princess Margaret Hospital, Hong Kong SAR

Aim: Duodenal stenting (DS) is a frequently performed palliative treatment for malignant gastric outlet obstruction but reintervention rates are not uncommon. Compartiatvely, EUS-guided gastrojejunostomy (EUS-GJ) is an emerging treatment alternative which possesses a promising clinical outcome with a good safety profile. The aim of this study is to compare the outcomes of DS and EUS-GJ.

Method: A retrospective cohort study from January 2022 to March 2024 in Princess Margaret Hospital was performed. Patients who received GS or EUS-GJ for GOO caused by inoperable malignancy were included. Primary outcomes included technical success (successful deployment of stent) and clinical success (a rise in one point in GOO symptoms score (GOOSS) in 5 days). Secondary outcomes were the rate of reintervention and complications within 30 days.

Result: A total of 58 patients were included. Thirty-five patients (60.3%) had DS while 23 (39.7%) had EUS-GJ. The most common causes of GOO were CA stomach (22, 37.9%) and CA pancreas (15, 25.9%). There were comparable rates of technical success [DS: 34 (97.1%) vs. EUS-GJ: 22 (95.7%), p = .76] and clinical success [DS: 29 (82.9%) vs. EUS-GJ: 20 (87.0%), p = .67]. Reinterventions were required in 14 patients (40%) with DS but only in 2 patients (8.7%) with EUS-GJ (p = .002). There were no significant differences in the complication profile in terms of 30-day mortality, recurrent obstruction, biliary obstruction, gut perforation, and GI bleeding.

Conclusion: EUS-GJ for malignant GOO has a similar success rate and complication rate compared with duodenal stenting. However, EUS-GJ is associated with lower rates of reintervention.

Department of Surgery, Tseung Kwan O Hospital, Hong Kong SAR

Aim: The prevention of anastomotic complications is an important topic in rectal cancer surgery. Currently different circular stapling devices, including double-row and triple-row, are available. We aimed to investigate whether significant difference exists between the two technologies in terms of anastomotic complication rates, as well as to identify surgical factors that affect anastomotic complication rates.

Methods: 61 patients with elective rectal cancer surgeries (AR, LAR or TME) between January 2022 and May 2024 in a single surgical center were included and divided into double-stapler and tri-stapler groups. Patient demographics, oncological factors and surgical characteristics were compared.

Results: No statistically significant difference in patient demographics and oncological factors were demonstrated between double-stapler and tri-stapler groups. Rates of anastomotic bleeding was similar (p = .566; double-stapler, 5.3%, tri-stapler, 2.4%). Anastomotic leakage and intra-op redo-anastomosis were only reported in tri-stapler group (p = .342; tri-stapler, 4.8%), though the results were not statistically significant. Anastomotic leak rate was higher in patients with diverting stoma creation (p = .026; stoma, 11.1%, no stoma, 0%) while other investigated surgical factors had no statistically significant impact on anastomotic complication rate.

Conclusions: No statistically significant difference in anastomotic complication rates associated with the use of double- or triple-row circular stapling devices in rectal cancer surgery was shown in this single center study. Diverting stoma was still recommended for those with anticipated higher anastomotic leakage risk.

Department of Surgery, Caritas Medical Centre, Hong Kong SAR

Aim: To assess & compare the outcomes of Irrigation-lavage versus Suction-alone during emergency laparoscopic appendectomy, in patients with uncomplicated and complicated acute appendicitis.

Methods: A retrospective study of patients between 2022 and 2023 in Caritas Medical Centre was conducted. Clinical data regarding patient demographics, clinical presentation, operative procedures and surgical outcomes were retrieved from an electronic database, and statistically analysed. Subgroup analysis was performed for complicated appendicitis & uncomplicated appendicitis.

Results: This study included 94 cases (50 Irrigation-lavage; 44 Suction-alone). Baseline demographics were similar between the two groups, in terms of age, BMI, gender, ASA, pre-operative WBC count, and symptom duration. All patients received emergency laparoscopic appendectomy. The primary outcome is intra-abdominal abscess rate. The secondary outcomes include length-of-stay, operative duration, overall complication rate, wound complication rate, and re-operation or image-guided drainage rate. Results show that suction-alone is significantly associated with shorter operative duration (70.8 vs. 86.8 min, p = .002) and reduced length-of-stay (3.02 vs. 4.79 days, p < .001). For suction-alone, there is also a trend towards lower overall complication rate (6.8% vs. 14.0%), intra-abdominal abscess rate (2.3% vs. 10.0%), prolonged ileus rate (2.3% vs. 10.0%), and image-guided drainage rate (0% vs. 2.0%). Subgroup analysis of uncomplicated appendicitis group demonstrated significantly shorter operative duration (67.5 vs. 80.0 min, p = .027) for suction-alone. Length-of-stay and overall complication rate were lower for suction-alone in both uncomplicated and complicated appendicitis groups.

Conclusions: Irrigation-lavage does not confer extra advantage, whilst significantly prolongs operative duration. Suction-alone should be considered in both uncomplicated and complicated appendicitis to achieve comparable outcomes.

Department of Surgery, Tuen Mun Hospital, Hong Kong SAR

Aim: We aim to investigate different local pharyngeal anaesthesia regimens in minimizing patient throat discomfort during unsedated esophagogastroduodenoscopy (EGD).

Methods: A retrospective study of patients with unsedated EGDs with Xylocaine used, performed from October, 2022 to June, 2023 was done. Patients with communication difficulties, altered gastrointestinal anatomies, aborted or refused EGDs, or allergies were excluded. The number of Xylocaine spray puffs and the duration of which the patients were asked to swallow (i.e. sprayed duration) were categorized into four groups: group 1 patients received variable spray puffs and sprayed durations, group 2 received 10 puffs and variable sprayed durations, group 3 received 10 puffs and 1-min sprayed durations. Patients in group 4 were asked to swallow immediately after received 5 puffs, then received 5 puffs more and asked to swallow after positioning, and topical Xylocaine was used. Patients' pre-procedure anxiety levels were scored on a scale of 1–5, with 4 and 5 regarded as significant anxiety. The primary outcome was patients' throat discomfort levels post-procedure, scored on a scale of 1–5, with 4 and 5 regarded as significant discomfort.

Results: 1016 patients were recruited after exclusion. Older, male, absence of significant anxiety and diagnoses of gastritis were associated with less significant discomfort. In univariate analysis, less lignocaine spray puffs were associated with less significant discomfort post-procedure, however this did not reach statistical significance in multivariate analysis. No difference was observed with different sprayed durations.

Conclusions: This study showed pre-procedural anxiety was the only modifiable factor for post-procedural throat discomfort.

Department of Surgery, United Christian Hospital, Hong Kong SAR

Aim: The aim of this study was to compare outcomes and post operative complications of POEM and Laparoscopic Heller Myotomy in patients with achalasia.

Materials and Methods: This was a retrospective review on patients with achalasia who underwent POEM and Laparoscopic Heller Myotomy from the period 2004 to 2023 in United Christian Hospital, Hong Kong. Data was retrieved from our local hospital database. Patients' demographics, operative time, hospital stay, clinical outcome/dysphagia, post operative reflux symptom/protein pump inhibitor use, recurrence rates were compared.

Results: Both Heller and POEM group showed similar efficacy in relieving dysphagia with success rate of 77% and 83% respectively (p .95). For post operative reflux, POEM group had a higher rate of regular PPI use 75% than in Heller group 38% (p .036). Recurrence rates were 19% for Heller group, there was no recurrence case in POEM group (p > .1).

Conclusions: POEM and Heller Myotomy with fundoplication both showed similar effectiveness on relieving dysphagia. POEM, however, was more associated with reflux symptoms, which was usually self-limiting with proton pump inhibitor use. Further randomized control trials on long term outcome of POEM and cost-effective analysis can lead to a better conclusion on treatment of choice for achalasia.

Department of Surgery, Pok Oi Hospital, New Territories West Cluster, Hong Kong SAR

Aim: Obturator hernia is associated with high mortality and morbidity. This study aims to investigate if patients' outcome and treatment strategies differ in recent two decades.

Methods: All patients diagnosed of obturator hernia in New Territories West Cluster (Tuen Mun Hospital and Pok Oi Hospital) between 01/01/2002 and 31/12/2023 were included. Patient characteristics, diagnosis modality, time before intervention, and outcomes were compared.

Results: 30 Patients were included, aged between 71 and 98 with a median of 86. All of them are female. 63% had bowel ischemia and same-episode mortality is 43%. They were put into two groups (Group A – 01/01/2002 to 31/12/2012; Group B – 01/01/2013 to 31/12/2023). There was no significant difference between the age (p = .1471) and sex (p = 1). 60% of group A, 100% of group B has undergone Computed Tomography Scan for diagnosis (p = .0169). Median of days between admission and operation were 4 days for Group A, 1 day for Group B (p = .0065). Bowel ischemia occurs in 73% in Group A, 53% in Group B (p = .2557). Same episode mortality was 53% in Group A, 33% in Group B (p = .4621).

Conclusions: In recent decade, increasing use of Computed Tomography Scan is observed for diagnosis of obturator hernia. The time of delay in operation was significantly reduced. Although the rate of bowel ischemia and mortality is not statistically significantly reduced, there is trend of reduction. Further study with a larger sample size or a multi-center study may be attempted to establish improvement of care to patients with obturator hernia.

Department of Surgery, Pok Oi Hospital, Hong Kong SAR

Aim: To evaluate factors affecting survival on male breast cancer patients in the past 11 years in a local hospital.

Methods: All male patients diagnosed of breast cancer in Department of Surgery, Pok Oi Hospital between 01/01/2012 and 31/12/2022 were included. Log-rank test was used to determine if factors such as age of diagnosis, cancer stage, use of adjuvant therapies affect survival of male breast cancer patients, and Kaplan–Meier curves were generated.

Results: 25 patients were recruited, aged of 57 to 97 years at time of diagnosis. 16%, 28%, 40%, 8% and 8% were stage 0, 1, 2, 3, 4 respectively. 24%, 32%, 4% and 72% of them received chemotherapy, radiotherapy, targeted therapy, and hormonal therapy respectively. There was no recurrence. Two-year overall survival was 76%. Statistically significant difference in two-year survival was demonstrated for age above 80 (p = .049), presence of nodal metastasis (p = .016), and stage (p = .002). It is worth-mentioning that stage 0–2 has significant better two-year survival than stage 3–4 (p = .001). There is no significant difference on survival for presence of hormonal receptors (p = .257), T staging (p = .202) and use of adjuvant therapies (p = .485 for chemotherapy; p = .881 for radiotherapy; p = .593 for targeted therapy; p = .789 for hormonal therapy).

Conclusions: This study demonstrated that age, nodal metastasis and stage affect the survival of breast cancer in local male patients. They may be followed-up for a longer period to investigate long-term survival and recurrence. Recruitment over a longer period or a multi-center study may increase the sample size to achieve higher power.

Department of Surgery, Queen Elizabeth Hospital, Hong Kong SAR

Aim: Laparoscopic appendicectomy is a commonly performed emergency operation for acute appendicitis worldwide. However, conversion to open appendicectomy is sometimes necessary. The aim of this study is to identify the risk factors associated with conversion to open surgery in laparoscopic appendicectomy.

Methods: This was a retrospective study on 219 patients with diagnosis of acute appendicitis who underwent emergency appendicectomy with attempt in laparoscopic approach in Queen Elizabeth Hospital from January 2023 to December 2023. Patient demographics, clinical, preoperative, intraoperative and postoperative data were extracted and analysed for association with conversion to open surgery.

Results: The conversion rate was 16.9% (37/219). Conversion from laparoscopic to open appendicectomy is associated with older age (55 vs. 48 years, p = .028), longer duration of symptoms to operation (151.46 vs. 78.12 h, p < .001), lower serum albumin level (31.8 vs. 36.3 g/L, p < .001), worse ASA score (U = 4279, p = .002). Mann–Whitney U test showed conversion group has worse image-based and intraoperative American Association for the Surgery of Trauma (AAST) score for appendicitis (U = 4734, p < .001 and U = 4607, p < .001 respectively). Conversion group has longer duration of surgery (158 vs. 98 min, p < .001), greater blood loss (190 vs. 42 mL, p < .001) and longer length of hospital stay (12 vs. 6 days, p < .001). Multivariate analysis by logistic regression showed independent risk factor for conversion was longer duration of symptoms to operation (p = .004).

Conclusions: Patients with longer duration of symptoms of appendicitis has a higher risk for conversion to open in laparoscopic appendicectomy. Timely performed laparoscopic appendicectomy is associated with more favourable clinical outcome.

Department of Surgery, North District Hospital, Hong Kong SAR

Aim: To compare clinical efficacy of continuous elastomeric local anaesthetic infusion pump with local anaesthesia wound infiltration for postoperative analgesia following elective open hepatectomy.

Methods: This was a retrospective study of patients underwent elective open hepatectomy in North District Hospital between January 2023 and May 2023. Patients who received continuous levobuipivocaine infusion to right subcostal wound for first 48 h postoperatively (Easypump group) were compared with patients receiving wound infiltration with levobuipivocaine only at the end of operation (LA group). Subgroup analysis was performed on patient who also received transverse abdominis plane (TAP) block with either Easypump or LA.

Results: Fourteen patients were identified, with six patients receiving TAP block intraoperatively. All patients were aged between 56 to 72 years with similar background demographics. In Easypump group versus LA group, Mann–Whitney U test showed significantly lower morphine consumption via PCA in Easypump group (median 50.5 vs. 75 mg, U = 16, p = .03). There were no significant differences between the two groups in terms of pain score at rest, pain score on exertion, length of hospital stay (LOS), and satisfaction score. In subgroup analysis comparing patients receiving TAP block and either Easypump or LA, there were no statistically significant differences in total morphine consumption via PCA, pain scores at rest and on exertion, LOS, and satisfaction score.

Conclusions: Continuous levobuipivocaine infusion using elastomeric pump to right subcostal wound after open hepatectomy resulted in lower post-operative morphine consumption compared to local anaesthesia wound infiltration.

Department of Surgery, The University of Hong Kong, Hong Kong SAR

Aim: Immediate breast reconstruction (IBR) following mastectomy has become increasingly common in patients with breast cancer. This study aims to provide a comprehensive assessment of short-term complications associated with various IBR techniques based on a local territory-wide database.

Methods: A population-based retrospective study was conducted on patients with breast cancer who underwent IBM under the Hospital Authority between 2013 and 2023. The study evaluated complications within 90 days post-mastectomy that required any procedural interventions. Statistical analyses, including chi-square tests and logistic regression, were performed to identify associations between reconstruction types and complications.

Results: A total of 1436 patients underwent post-mastectomy reconstruction and 82.1% of them was IBR. Types of reconstruction has remained static over the last decade with more than 80% having autologous based and less than 20% expander-implant based reconstruction. Among 1180 female patients analysed, 83.6% underwent autologous based reconstruction, while 15.9% received tissue expander and/or implant, and 0.4% had a combination of both. 97.6% had unilateral whereas 2.4% had bilateral reconstruction. The overall complication rate was 13.6%. Among 161 patients presented with complications, 1.5% required wound debridement or revision procedure under local anaesthesia/monitored anaesthesia care and 98.5% required re-operations under general anaesthesia. 42.9% was TRAM flap reconstruction, 35.4% was tissue expander and/or implant and 14.3% was LD flap reconstruction. A significant association was found between breast reconstruction types and postoperative complications (p < .001).

Conclusion: This study provides valuable population-level data on short-term complications following IBR for patients with breast cancer.

Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, Prince of Wales Hospital, Hong Kong SAR

Aim: Laparoscopic major hepatectomy is technically challenging. Use of robotic system may help to overcome technical difficulties, but supporting clinical evidence is scarce. This study aims to compare our experience and perioperative outcomes in laparoscopic or robotic major hepatectomy for treatment of hepatocellular carcinoma.

Methods: A retrospective review of prospectively collected clinical data was performed for all patients who underwent laparoscopic major hepatectomy (LMH) or robotic major hepatectomy (RMH) for treatment of hepatocellular carcinoma at the Prince of Wales Hospital, Hong Kong. Patient characteristics and perioperative outcomes of the two groups were compared.

Results: Between December 2007 to December 2023, 20 LMH and 27 RMH were performed. Mean tumour size was larger in LMH group (LMH: 5.3 cm vs. RMH: 3.5 cm, p = .037). More right hepatectomy was performed in LMH group (LMH: 15 vs. RMH: 6, p < .001), while more left hepatectomy was performed in RMH group (LMH: 4 vs. RMH: 21, p < .001). All cases achieved R0 resection. There was one in-hospital mortality in LMH and none in RMH. RMH had significantly shorter length of stay (LH: 7 days vs. RH: 5 days, p = .001). No significant difference was noted in conversion rate (LMH: 15% vs. RMH: 11.1%, p > .999), median blood loss (LH: 145 mL vs. RH: 100 mL, p = .303) and median operative time (LMH: 370 min vs. RMH: 360 min, p = .698). There was no significant difference in overall survival or disease-free survival curves.

Conclusion: The outcomes of robotic major hepatectomy for hepatocellular carcinoma are comparable to laparoscopic major hepatectomy, with possible shorter length of stay.

Department of Surgery, Queen Elizabeth Hospital, Hong Kong SAR

Aim: Laparoscopic fundoplication is an alternative for GERD patients who are poorly responsive to or opt not for long-term PPI. Yet, some patients experience ongoing symptoms or develop complications after the procedure. This study aims to review the outcomes of laparoscopic fundoplication in a single centre and identify predictive factors for good surgical outcomes.

Methods: Sixty seven GERD patients who underwent laparoscopic fundoplication between January 2014 and December 2023 in Queen Elizabeth Hospital were retrospectively analysed. Patient demographics and clinical parameters were compared against post-operative outcomes.

Results: 80.6% patients had decreased PPI requirement, 82% patients had reduced severity of Barrett's oesophagus and 83.6% patients reported improved GERDQ score at 3 months. PPI responders more likely had decreased PPI requirement (p = .047), completely weaned PPI (p = .022) and no residual symptoms (p < .001) post-operation. Dor and non-Dor fundoplication showed comparable outcomes, while Dor fundoplication was associated with a stronger correlation between PPI response and good surgical outcomes including decreased PPI requirement (p = .079 vs .214), no residual symptoms (p = .016 vs. p = .024) and reduced severity of Barrett's oesophagus (p = .023 vs. p = .0829). DeMeester score, size of hiatal hernia and severity of esophagitis had no correlation with outcome. 2 Patients (3%) had post-operative dysphagia requiring endoscopic dilatation and oesophageal perforation respectively. None required reoperation.

Conclusion: PPI responsiveness is the sole predictive factor for favourable surgical outcome. Poor PPI responders may potentially benefit more from Toupet and Nissen fundoplication over Dor fundoplication. Laparoscopic fundoplication is overall a safe and effective treatment option for GERD patients with low complication rate.

Department of Surgery, Queen Elizabeth Hospital, Hong Kong SAR

Aim: Benign intranodal thyroid tissue was first reported in 1942. Differentiating it from nodal metastasis can be challenging and has a profound impact on subsequent management. This study aims to review the pathological features of benign intranodal thyroid inclusions and formulate the optimal management.

Methods: This study reviews the literature and reports a case of benign intranodal thyroid tissue with history of benign ipsilateral thyroid nodules.

Results: A 17-year-old man with history of right hemi-thyroidectomy in mainland China for benign thyroid nodules had several enlarging right upper and middle cervical lymph nodes with intranodal solid components on ultrasound. FNA of one right lower cervical lymph node showed follicular cells with scanty lymphocytes. Subsequent excisional biopsy showed large thyroid inclusions featuring circumscribed non-encapsulated follicles containing abundant colloid. Completion thyroidectomy and selective right neck dissection was performed at Queen Elizabeth Hospital. Final pathology of right cervical lymph nodes showed intranodal thyroid tissues not diagnostic of thyroid carcinoma. Diagnosis of thyroid inclusions can be challenging. Meyer and Steinberg proposed a set of histological criteria characteristic of thyroid inclusions including extent of inclusions, silhouette, localization, absence of microcalcification and desmoplastic stroma. With the emergence of immunohistochemical and molecular technologies, subsequent studies suggest that the diagnosis can be further supported by immunohistochemical and molecular profile which is inconsistent with thyroid cancer.

Conclusion: Benign intranodal thyroid tissue is rare but increasingly recognized. Knowledge on benign thyroid inclusion and multidisciplinary collaboration among pathologists, radiologists and surgeons is crucial in establishing this diagnosis and formulating an appropriate management.

Department of Surgery, Tuen Mun Hospital, Hong Kong SAR

Aim: Endoscopic submucosal dissection (ESD) is an advanced endoscopic technique used to resect large or complex colonic polyps. However, data on the clinical outcomes of ESD for colonic polyps are limited. The aim of this study was to evaluate the 8-year clinical outcomes of ESD for resection of colonic polyps at a single tertiary care center.

Method: This was a retrospective descriptive study of patients who underwent ESD for colonic polyps at our institution between January 2016 and June 2024. Patient demographics, polyp characteristics, procedural details, and outcomes including ESD success rate, en-bloc resection rate, adverse events, length of hospital stay, 30-days readmission rate and histopathology data were collected and analysed.

Results: 458 patients underwent ESD for colonic polyps during the 8-year study period. The mean patient age was 67.9 ± 8.9 years and 62.9% were male. 52.2% of the polyps were located in proximal colon, the mean polyp size was 31.3 ± 12.9 mm, majority of the polyps were benign (88.6%). The mean procedure time was 134.4 ± 82.4 min. ESD was successfully performed in 87.6% of patients, while en-bloc resection rate was 82.2%. Bowel perforation rate was 12.4%. The mean hospital stay was 0.97 ± 2.32 days, and 30-days readmission rate was 1.7%.

Conclusion: ESD is an effective treatment for large and complex colonic polyps, with high rates of successful en-bloc resection. However, the procedure carries a non negligible risk of bowel perforation. Careful patient selection and meticulous techniques are crucial to the safety and efficacy of ESD.

Department of Surgery, Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR

Aim: Mirizzi syndrome (MS) is a rare complication of gallstone disease with high morbidity. Open surgery has been considered the gold standard approach for operation, while laparoscopic and robotic approaches have been adopted as potential alternatives. This study aims to evaluate the safety and efficacy of robotic approach for surgical treatment of MS.

Methods: Fourteen patients with MS underwent robotic operations at our centre from August 2010 to March 2023. Procedures include six total cholecystectomies, with exploration of common bile duct (ECBD) in two of them, and eight partial cholecystectomies, with cholecystectoplasty in three of them, ECBD in six of them. Roux-en-Y hepaticojejunostomy was performed in two patients. Patient demographic, operative findings and outcome were retrospectively reviewed.

Results: Nine male and five female patients were included. Their median age was 71 (Range: 35–86). Two patients presented with acute cholecystitis and 12 presented with acute cholangitis. Six patients had McSherry type I MS and eight had McSherry type II MS. Pre-operatively, one patient received percutaneous transhepatic biliary drainage while 13 patients received endoscopic retrograde cholangiopancreatoscopy (ERCP) for internal drainage. Mean operation time was 168 ± 50 min. Mean length-of-stay was 5.4 days (SD ± 1.4 days). Median blood loss was 3 mL (Range: 0–20 mL). No open conversion was required and no post-operative mortality was noted. One patient (7%) had wound infection, otherwise there was no post-operative complication. One patient (7%) had residual ductal stone requiring post-operative removal with ERCP.

Conclusion: Robot-assisted laparoscopic operation is a safe and effective approach in managing MS.

Faculty of Medicine, The University of Hong Kong, Hong Kong SAR

Aim: Solitary fibrous tumours (SFTs) in breast is a rare entity with only 60 reported cases. We describe two cases of breast SFT and a comprehensive literature review, aiming to contribute to the currently limited knowledge.

Method: Pathology database involving major surgical centres in Hong Kong up to June 2023 was assessed for the diagnostic code of SFT. A systematic literature search was also conducted to identify all reported cases of breast SFT across multiple scientific databases.

Results: Pathology search yielded 2 cases of breast SFT in 2 Chinese female patients without family history of breast cancer. They both presented with a palpable breast lump looking suspicious on ultrasound (BIRADS 4), and both underwent surgical excision with definitive diagnosis made through immunohistolochemistry of surgical specimen. Literature search of reported breast SFT yielded 60 cases. 50 cases reported clinical presentation, mostly with a palpable breast mass without specific clinical features (n = 36, 72%). 14 cases reported ultrasonography features and 11 (78.6%) were suspicious (≥ BIRADS Grade 4). 49 cases mentioned treatment modality and all underwent surgical excision. Although most SFTs are indolent, two (4.1%) patients experienced recurrence—one was found 18-month post-operation, and the other 8-month post-operation with distant metastasis. Hence, long-term follow up is crucial.

Conclusion: We report two cases of breast SFT together with a comprehensive literature review to contribute to the currently limited knowledge of the disease. Our work demonstrated the rarity of this pathology and the importance of long term follow-up.

Department of Surgery, Queen Mary Hospital, Hong Kong SAR

Aim: A reliable biomarker to predict hepatocellular carcinoma (HCC) recurrence after hepatectomy is lacking. Positron emission tomography (PET) has been used in staging and diagnosis of HCC in Hongkong, but whether PET uptake will predict HCC recurrence after hepatectomy remains unknown. We hypothesized that pre-operative 18F-fluorodeoxyglucose (18F-FDG) uptake on PET predicted HCC recurrence after hepatectomy.

Methods: This was a retrospective study of prospective collected data (2004–2019). The cut-off for 18F-FDG uptake on PET to predict HCC recurrence was determined by Youdens' index. Patients were treatment naïve before PET-CT, followed by hepatic resections. Patients were stratified into PET+ve and PET-ve group base on the cut-off.

Results: 267 patients diagnosed with HCC who underwent hepatic resections had preoperative PET scan. The cut-off for 18F-FDG PET positivity was 1.526 (AUC = 0.674, 95% CI 0.608–0.741, p < .001). 155 patients were PET-ve and 112 patients were PET+ve. The PET+ve group had larger tumours (8.25 vs. 3.5 cm, p < .001), more microvascular invasion (67 vs. 36.1%, p < .001), more poorly differentiated tumours (24.8 vs. 16.7%, p = .03) and higher AFP≥100 ng/mL (49.1 vs. 23.2% p < .001). The time to recurrence was shorter in PET+ve patients (8.4 vs. 32.7 months, p < .001) and there was more extrahepatic recurrence (8.9 vs. 2.6%, p < .001). The PET-ve group had better overall and disease-free survival rates (p < .001).

Conclusions: PET+ve was associated with higher AFP and unfavourable tumour biology, with a higher risk of recurrence and inferior survival. 18F-FDG PET should be explored prospectively as a biomarker in HCC patients.

Division of Neurosurgery, Department of Surgery, Queen Mary Hospital, Hong Kong SAR; Division of Neurosurgery, Neuromedicine Center, The University of Hong Kong – Shenzhen Hospital, China

Aim: To investigate the rate of ventriculoperitoneal shunt (VP shunt) in aneurysmal subarachnoid patients (SAH) with initial external ventricular drainage (EVD) versus lumbar drainage (LD) or lumbar pucture (LP).

Method: This was a three-year retrospective cohort study of adult patients with good grade aneurysmal SAH who were admitted to Queen Mary Hospital (QMH) and The University of Hong Kong – ShenZhen Hospital (HKU-SZH) between January 2020 and December 2022. Patient data from QMH was drawn from the Clinical Data Analysis and Reporting System (CDARS) in the Clinical Management System. Patient data from HKU-SZH was drawn from the Hospital Information System (HIS). The data was analysed with the SPSS program. The rates of performing VP shunting in these SAH patients after performing either an EVD or a LP/LD were compared. Patients with both EVD and LP/LD done were excluded.

Results: There were 45 good grade aneurysmal SAH patients admitted to QMH. Among which, there were 20 patients who had EVD done and 6 patients who had LP/LD done. 55% of the patients with EVD done needed a VP shunt. 33% of the patients with LP/LD done needed a VP shunt. For HKU-SZH, there were 12 good grade aneurysmal SAH patients admitted. Among these, there were 2 patients who had EVD done and 10 patients had LP/LD done. None of the HKU-SZU patients needed a VP shunt.

Conclusion: Serial LP has a significant lower shunt dependent hydrocephalus in aneurysmal SAH patients.

Department of Neurosurgery, Queen Elizabeth Hospital, Hong Kong SAR

Objective: For non-lesional refractory epilepsy, the epileptogenic zone is difficult to delineate. The video-EEG findings are discordant. The advent of invasive stereotactic electroencephalograph (SEEG) leads to more accurate lateralisation and localisation of the seizure foci.

Methods: Case study with Augmented Reality Demonstration.

Results: We present a clinical case of a middle-aged male with non-lesional refractory epilepsy. His frequency of monthly seizure attack was 2. It began with cephalic aura, hearing loss, later became dialeptic, left facial twitching, drooling of saliva, mild jerking of left upper limb, aphasia, eventually post-ictal amnesia. With the discordant non-invasive workup findings, invasive SEEG was adopted. The hypotheses before SEEG implantation were (1) right frontal lobe was the most symptomatogenic one; (2) right temporal discharge preceded the right frontal discharge, and (3) left temporal discharge transmitted via insula and posterior commissure to the right side. Bilateral SEEG implantation was performed under frameless navigation guidance. 15 electrode leads were implanted according to the SEEG implantation map. More than 10 seizure attacks were recorded. The likely epileptogenic zone was right insula and posterior temporal lobe, with the transmission of epileptic discharge to right frontal lobe causing the symptoms. The hypothesis after SEEG implantation was made with the corresponding epileptogenic zone excised. No more seizure noted until the last visit.

Conclusion: SEEG is important to delineate the epileptogenic zone in case of inconclusive non-invasive workup findings of non-lesional refractory epilepsy. Satisfactory outcome might be achieved with resection surgery guided by SEEG findings.

Department of Surgery, Kwong Wah Hospital, Hong Kong SAR

Aim: To evaluate clinical outcomes of patients undergoing endovascular treatment of unruptured intracranial wide neck aneurysms, and factors associated with complete obliteration of aneurysm.

Method: This is a single-centre, 10-year retrospective review of patients who had received endovascular treatment for unruptured wide neck intracranial aneurysm from January 2012 to December 2021. Patients' demographics and aneurysms' characteristics were reviewed. Subsequent treatment modality and its rate of complete aneurysm obliteration on latest follow-up neuroimaging were analysed. Factors associated with complete obliteration were statistically evaluated.

Results: A total of 260 patients had unruptured intracranial aneurysms. 183 patients (49 male and 134 female, mean age 57) had wide neck aneurysms and they were recruited to our study. Some had multiple aneurysms so a total of 208 wide neck aneurysms were analysed. Simple coiling achieved a complete obliteration rate of 44% (mean dome-to-neck ratio 1.20). Flow-diverter insertion alone achieved complete obliteration rate of 75.9% (mean neck-to-dome ratio 1.09). Other adjunct-assisted coiling by stent or flow-diverter achieved a complete obliteration rate of 56.3% (mean dome-to-neck ration 1.20) and 85.3% (mean dome-to-neck ratio 1.34) respectively, with no in-stent stenosis. Subgroup multivariate analysis and regression analysis showed that complete obliteration rate is affected by aneurysm profile and treatment mortality. Aneurysm height is also a statistically significant factor affecting complete obliteration rate.

Conclusion: From this single-centre review, unruptured wide neck intracranial aneurysm with mean neck-to-dome ratio of less than 1.34 could be treated effectively by endovascular means.

Division of Neurosurgery, Department of Surgery, Queen Mary Hospital, Hong Kong SAR

Aim: To determine the potential predictors of treatment outcomes after posterior fossa decompression (PFD) for Chiari malformations.

Methods: Patients with Chiari malformations who had PFD performed in Queen Mary Hospital (QMH) and Hong Kong Children's Hospital (HKCH) from 2003 to 2023 were reviewed retrospectively. Clinical outcomes were measured according to Chicago Chiari Outcome Scale (CCOS). Posterior fossa and syrinx measurements were taken. Uni- and multivariate analyses were performed to determine potential predictors of post-operative outcomes.

Results: 53 patients were identified. Mean age at diagnosis was 18.8, and 62.3% were under 18 years old upon presentation. 58.5% of patients had typical Chiari symptoms. Pre-operative MRI showed syringomyelia in 86.8% and hydrocephalus in 20.8% of patients. PFD with duroplasty were performed in all patients. Laminectomy of C1 or beyond was performed in 98.1% of patients. Bilateral tonsillectomy was performed in 39.6%. Early complications were identified in 15.1% (n = 8) of patients, in which most did not require intervention. Radiologically, extent reduction or complete resolution of syrinx was noted in 69.2% of patients. Clinically, 58.5% had complete resolution of symptoms/remained asymptomatic. The average total CCOS was 14.1. Overall re-operation rate was 9.4% (n = 5). Uni- and multivariate analyses showed a statistically significant regression model (R = 0.94, R² = 0.88, F = 9.03, p = .001). Age at diagnosis (β = −0.78, p = .001), syrinx length (β = −0.27, p = .047) and clivus-torcula distance (β = 0.56, p = .01) were shown to be predictors of outcomes.

Conclusion: Posterior fossa decompression is a safe procedure with satisfactory radiological and functional outcomes. Pre-operative measurements of posterior fossa and syrinx can potentially predict treatment outcomes.

Department of Surgery, Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR

Aim: Giant aneurysms arising from extracranial portion of internal carotid artery are rare. Symptoms are more often caused by cerebrovascular insufficiency, rather than rupture or local compression. Possible treatment options include open ligation, surgical reconstruction, endovascular parent artery occlusion, stenting, and hybrid operation. Herein we present two cases treated with parent artery remodelling through flow divertor and open trapping respectively.

Method: Two patients presented with neck discomfort and Horner syndrome. Imaging revealed large extracranial carotid aneurysm at cervical region. Balloon occlusion test was performed prior to definitive treatment and showed good cross-flow. One of the patient received endovascular treatment, whereas the remaining one underwent open trapping of carotid artery.

Results: Procedure was performed uneventfully for both patients. Post-operatively, their conscious level remained good without significant deficit. Interval scan showed obliteration of aneurysm sac without recurrence. Due to the lack of evidence based treatment algorithm, the ultimate management plan is based upon the clinical presentation, surgeons' or interventionists' experience, accessibility of aneurysm and aetiology of aneurysm formation.

Conclusion: Treatment of giant aneurysm can be challenging. Endovascular reconstruction through stenting and open trapping are both feasible treatment options with good angiographic result and fair neurological outcome.

Department of Surgery, Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR

Aim: H3K27M altered diffuse midline glioma (DMG) is classified as a WHO Grade 4 paediatric type high grade glioma. The clinicopathological features remain poorly characterized in adult due to rarity. They are predominantly found in brainstem, thalamus and spinal cord. Intra-ventricular DMGs were scarcely reported. Herein, we report an adult case.

Method: A 42-year-old male patient presented with headache, drowsiness and left hemiparesis. Subsequent imaging revealed a well-defined 2 × 2.3 × 2.7 cm lesion at the frontal horn of right lateral ventricle with obstructive hydrocephalus. Patient underwent urgent external ventricular drainage, followed by septostomy and endoscopic biopsy.

Results: Histologically, the sections showed a glial tumour of moderate cellularity and areas of microvascular proliferation without necrosis. The Ki67 proliferative index was up to 30%. Immunohistochemically, the tumour cells were positive for H3K27M and negative for IDH1 or IDH2 mutations. It demonstrated neither ATRX mutation nor p53 mutation. The diagnosis of diffuse midline glioma, H3K27M altered was established. The MGMT gene promoter methylation was not detected. Patient eventually underwent craniotomy for tumour excision. Post-operatively, patient recovered well without focal neurological deficit. Patient was referred to oncology unit for adjuvant chemoradiotherapy.

Conclusion: Diffuse midline glioma is a rare and highly aggressive tumour, with median survival ranging from 9 to 16 months. The imaging features lack specificity which can mimic other intra-ventricular tumours, such as ependymoma or subependymoma. Prompt histological diagnosis is warranted to correctly identify these tumours due to its prognostic significance.

Department of Surgery, Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR

Aim: To review the centre's past carotid blowout patients and their outcomes.

Method: This is a retrospective review of patients with carotid blowout at Pamela Youde Nethersole Eastern Hospital from 2021 to 2023. The patients' data including demographics, primary pathology and subsequent radiotherapy, management of blowout, and outcome were analysed.

Result: 6 patients with carotid blowout were managed over the 3 year period, with post-radiotherapy to blowout interval ranging from 11 to 232 months. Prior radiotherapy dose ranged from 40 to 144 Gys. 3 cases were managed by trapping, and the remaining 3 by stenting. Half of the patients reached mRS 6 within 6-months post-op, and overall survival ranged from 0.76 to 8.4 months. Cause of death included intracerebral haemorrhage and nasopharyngeal carcinoma (NPC) recurrence with repeat blowout, and NPC recurrence with ventriculitis.

Conclusion: Carotid blowout is not an uncommon pathology and carries poor prognosis. It can occur at short interval post radiotherapy despite within well-established dosage guidelines.

Department of Surgery, Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR

Aim: To review the centre's past brain metastases patients and their outcomes.

Method: This was a retrospective review of brain metastasis patients who underwent craniotomy at Pamela Youde Nethersole Eastern Hospital from 2018 to 2022. The patients' data including demographics, premorbid, primary pathology, brain metastasis locations, other adjuvant treatment, and outcome were analysed.

Result: Median progression free survival was 6.4 months, whilst median overall survival (mOS) was 16.1 months. Patients with premorbid Karnofsky Performance Status (KPS) ≥80 and post-op stereotactic radiosurgery (SRS) had longer survival duration. (mOS 31.8 months for KPS ≥80 vs. 8.7 months for KPS <80 (p-value .001), and mOS 35.3 months for SRS vs. 15.4 months for without SRS (p-value .004)). Conversely, age, dexamethasone use, tumour size, number of brain metastasis, location of metastases, SRS dose and timing, whole-brain radiotherapy, chemotherapy, or targeted therapy use were not correlated with a statistically significant change in median overall survival.

Conclusion: Patients with premorbid of KPS ≥80 and post-op SRS had a longer median overall survival.

Department of Surgery, Hong Kong Children's Hospital, Hong Kong SAR

Aim: We report a case of an adolescent boy presented with dysphagia, as well as iron deficiency anaemia with poor nutrition, diagnosed of oesophageal web on oesophagoduodenoscopy (OGD) and contrast swallow. Dysphagia improved with correction of iron deficiency anaemia.

Method: A 14-year-old Pakistan boy initially presented to General Paediatrics in 2018 for viral infection with fever, and reported symptoms of blood-stained stool with constipation, as well as dysphagia. Biochemical workup confirmed iron deficiency anaemia which persisted for years, with patient's suboptimal compliance to iron supplement, further worsened by an unbalanced diet picky on snacks. Contrast swallow in November 2023 also showed a short segment of persistent focal narrowing in the cervical oesophagus (C4/5 level) with luminal width down to 2 millimetres. It was followed by oesophagogastroduodenoscopy in December 2023 showing cervical oesophageal web at 15 cm from incisor, which was only able to be negotiated through by n-scope. He was given regular intravenous iron supplement. Dysphagia subsequently resolved gradually within 6 months after iron correction without any endoscopic intervention.

Results: Dysphagia due to oesophageal web resolved quickly with correction of iron.

Conclusion: A rare case of Plummer-Vinson syndrome (PVS) was reported, clinically with typically the triad of iron deficiency anaemia, dysphagia and oesophageal web, which could be effectively managed with repletion of iron. Workup for iron profile should be performed in cases presented with dysphagia with such radiological and endoscopic finding of oesophageal web.

Department of Surgery, The University of Hong Kong, Hong Kong SAR

Aim: Phimosis is a common paediatric surgical condition. With artificial intelligence, many medical information are now available on large language models (LLM). In anticipation of more parents searching medical information with LLM nowadays, a readability, quality, and accuracy evaluation on the information from LLM on phimosis is carried out.

Method: Six questions related to phimosis on it's definition, diagnosis, treatment options and potential complications was inputted into LLM-Chatbots (ChatGPT-3.5, Gemini-1.5, and Claude-3). All responses were reformatted, shuffled and recombined into three passages for single-blind scoring on accuracy by three paediatric surgeons. The responses were assessed for readability using the Gunning-Fog score, SMOG index, Dale-Chall score, and for quality using the DISCERN score.

Results: Comprehension of the information was considered difficult with a mean Gunning-Fog score, SMOG index score, Dale-Chall score of 14.2 ± 2.6, 11.3 ± 2.2 and 9.9 ± 0.9 respectively. The mean summed DISCERN score was 39.6 ± 2 out of 80. Claude-3-sonnet was considered of poor quality while the others were fair. The mean accuracy score of the LLM-chatbots was 4.4 ± 0.4 out of 5. The three LLMs performed similarly on readability and accuracy. The LLM-chatbots generally scored well in providing treatment options and their mechanisms, while lacked references and information regarding treatment benefit, risks of alternative treatments and impact on quality of life.

Conclusion: The three LLM-chatbots performed similarly and satisfactorily in terms of accuracy. Yet they are considered of suboptimal quality and difficult for public to comprehend. It is recommended to combine with other reliable data sources to improve clinical practice and decision-making.

Department of Surgery, Hong Kong Children's Hospital, Hong Kong SAR

Aim: Chemotherapy-induced acute pancreatitis (AP) causes significant morbidities in paediatric haemato-oncological patients. The present study aims to review the characteristics and predictors in clinical outcome in these patients.

Methods: A retrospective analysis of all consecutive patients with haemato-oncological malignancy under 18 years old who developed chemotherapy-induced AP in a tertiary centre between 6/2019 and 6/2024 was done. Patient's demographics, biochemical results, radiological findings and outcomes were evaluated. Clinical parameters predicting the need for intensive care unit (ICU) admission were analysed.

Results: Out of 31 patients identified, 16 required ICU admission. Pegaspargase (n = 19, 61.3%), Erwinia asparaginase (n = 3, 9.7%), L-asparaginase (n = 3, 9.7%), mercaptopurine (n = 1, 3.2%) and their combinations (n = 5, 16.1%) were identified as causative agents. Between the ICU and non-ICU groups, no statistically significant difference in the median age (p = .73), gender (p = 1.0), body weight percentile (p = .14), diagnosis (p = .38) and causative drugs (p = .76) were found. Abnormal INR (93.8% vs. 33.3%; p < .05) and Lipase level over 4000 U/L (75% vs. 33.3%, p < .05) at presentation were associated with ICU admission. The presence of pleural effusion (87.5% vs. 33.3%; p < .05), ascites (87.5% vs. 46.7%; p < .05) and necrotising pancreatitis (25% vs. 0%; p < .05) on initial imaging were also predictive factors for ICU admission. Eight of them required surgical intervention or interventional radiology procedures.

Conclusions: Abnormal INR, Lipase over 4000 U/L at presentation, the presence of pleural effusion, ascites and necrotizing pancreatitis are found to be predictive of ICU admission in paediatric haemato-oncological patients with chemotherapy-induced acute pancreatitis. Early recognition of patients at risk can facilitate timely ICU involvement and subsequent management.

Department of Surgery, Hong Kong Children's Hospital, Hong Kong SAR

Aim: To present the youngest paediatric case of Partial Segmental Thrombosis of Corpus Cavernosum (PSTCC) in literature and conduct a literature review from 1976 till 2024.

Method: Searched key terms ‘Partial Priapism’, ‘Partial Segmental Thrombosis of Corpus Cavernosum’ and ‘Partial Thrombosis of Corpus Cavernosum’ in PubMed and Google Scholar from 1967 till 2024. Analysis was done on the underlying aetiology, investigation, treatment, time for resolution of thrombus and prognosis.

Result: A 13-year-old boy presented with perineum pain and later diagnosed of PSTCC. Literature review found an additional 73 cases of PSTCC. Majority of patients (n = 54, 73.0%) was found to have underlying anatomical abnormalities of a transverse membrane. The main treatment offered was conservative (n = 49, 66.2%) using anti-thrombotic and analgesics. The other cases opted for surgical treatment including corporotomy or cavernosal spongiosum shunt (n = 16, 21.6%). Less invasive treatment included phenylephrine intracorporal injection (n = 4, 5.41%) and interventional radiology (n = 1, 1.35%). Treatment for the remaining cases was either unreported or not done (n = 4, 5.41%). Repeated imaging with either Colour Doppler Ultrasound (CDU) or Magnetic Resonance Imaging (MRI) reported complete resolution of thrombus after medical treatment (n = 23, 46.9%) with mean time of 5.2 months (SD 1.64). Most cases (n = 49, 66.2%) had complete resolution of symptoms with normal erectile function. The follow up interval had a median of 2 months.

Conclusion: PSTCC is a rare disease with most cases found to have underlying transverse membrane. Since 1994, the trend has been conservative treatment with good prognosis while surgical treatment is reserved as last resort.

Department of Surgery, Kwong Wah Hospital, Hong Kong SAR

Aim: Dermal substitutes have emerged in the last decade as potential alternative option for skin tissue defect coverage – one of which is Matriderm®, an artificial dermal matrix which could be simultaneously applied with split-thickness skin graft. This study aims to review the clinical outcomes of Matriderm® and skin grafting performed in Kwong Wah Hospital (KWH).

Method: A retrospective study of all patients who received Matriderm® dermal substitute and same-stage partial thickness skin grafting in Division of Plastic Surgery of Department of Surgery, KWH was conducted between 1/1/2022 to 1/1/2024. Patient data including age, comorbidities, procedural details (indication, defect location, defect size) were collected. Outcomes were assessed in terms of percentage of graft survival, which was defined as percentage of entire graft with good adherence to wound bed at 7 to 10 days post-operatively, as well as scar quality according to Vancouver Scar Scale (VSS).

Results: 21 patients were included in the study, with mean age of 53. The mean follow up was 8.8 months. Causes of defect varied from scar contracture release (28.6%), burn wounds (23.8%), skin cancer excision (14.3%), to soft tissue infection (9.5%) and free radial forearm flap donor site (4.8%). The average defect area was 52.9 ± 28.4 cm². Overall graft survival rate was 87%. Apart from 1 case of resultant scar contracture at finger webspace requiring surgical revision, scar pliability and height were satisfactory in general.

Conclusion: Matriderm®-augmented split-thickness skin graft is a versatile and valid reconstruction option for complex or full-thickness skin defects.

Department of Surgery, Queen Mary Hospital, Hong Kong SAR

Aim: Despite the introduction of oncoplastic techniques for breast conserving surgery, deformities still exist after BCS. Options for reconstruction in this group of patients are limited. Lipofilling is a reconstructive technique that can achieve good cosmetic results for these patients. However, there are limited publications despite the procedure being widely performed in various Western centers. The aim of this study is to fill the gap between clinical findings and literature, especially when the technique is further adopted into clinical practice.

Method: This is a randomized study comparing a standard breast conserving surgery alone to BCS with immediate lipofilling. Data including intraoperative, post-operative parameters and Patient Reported Outcomes by BREAST-Q are collected prospectively.

Results: A total of three BCS and immediate lipofilling have been performed to date out of six patients randomized. The percentage of breast volume excised ranged from 12.7% to 19.7%. There were no early post-op complications. The average reported breast pain was 4 (range 2–8) and 2.7 (2–4) on POD1 and week 2 respectively. Patients reported an increase in satisfaction of their breasts after the operation, BREAST-Q score increased from 39 to 63.

Conclusion: Our results in the first three patients randomized to receive immediate lipofilling showed that BCS with immediate lipofilling have low complications and a high level of satisfaction with good early cosmetic outcomes. Further recruitment of patients into this study and longer term outcomes would give important knowledge of the feasibility of such technique.

Hospital Authority, Hong Kong SAR

Aim: Non-tuberculosis mycobacterium (NTM) infection following aesthetic injection is a rare complication, occurring 2 per 100 000 person (Wentworth et al), and raises public health concern. It requires different diagnostic methods and treatments in comparison to usual skin and soft tissue infections. Thus we would like to explore this rare condition to achieve earlier diagnosis and better patient outcomes.

Method: Report of three cases of NTM infection in a single center, with analysis of clinical presentation and disease outcome. Literature analysis of this rare disease is also reviewed.

Results: NTM infection requires acid-fast bacilli culture as diagnosis, with different subtypes of mycobacterium requiring different combinations of prolonged intravenous antibiotics. Combined with excision of abscess or infective nodules has 91% treatment success rate in comparison to 57% for conservative treatment (Huang et al). Incision and drainage or aspiration with routine antibiotics does not suffice for complete treatment and is prone for recurrence.

Conclusion: Skin and soft tissue infection resistant to usual treatment following aesthetic injection raises concern for atypical infection such as non-tuberculosis mycobacterium infection. We should be vigilant and have early suspicion such that diagnosis and prompt initiation of antibiotics with input from microbiologists will not be delayed. Both medical and surgical treatment is essential for this disease entity.

Division of Urology, Department of Surgery, Queen Mary Hospital, Hong Kong SAR

Aim: Percutaneous nephrolithotomy (PCNL) is the standard treatment for renal stones larger than 2 cm. Mini PCNL has been suggested as a safer alternative to mitigate the risk of complications and achieve compare stone clearance. This study aims to compare the efficacy and safety profiles of mini PCNL versus standard PCNL.

Methods: This study examined PCNL procedures performed between 1st January 2007 and 31st March 2023, at Queen Mary Hospital and Tung Wah Hospital. Patient demographics, stone count and size, as well as the number and sizes of tracts, operative outcomes including stone-free rates, additional treatments, and complications such as blood loss, sepsis, and renal impairment, were examined.

Results: A total of 435 PCNL procedures were evaluated, with 68 (15.6%) underwent Mini PCNL (Group 1) and 367 (84.4%) underwent Standard PCNL (Group 2). Patient demographics, percentage of first-time PCNL and stone count were comparable. However, the Mini PCNL group had a smaller pre-operative stone diameter (22.9 vs. 30.8 mm, p < .001) and size (295.9 vs. 624.2 mm², p < .001). There were no significant differences in stone-free rate and number additional treatment. Mini PCNL showed a longer operation time (170 vs. 151 min, p = .022) and shorter length of stay (4.62 vs. 6.83 days, p < .001). Complications including blood loss, need of transfusion, postoperative fever, sepsis, extended antibiotic use, and renal impairment were comparable. The postoperative PCN duration was shorter in patients with mini PCNL, while the duration of JJ stent was comparable.

Conclusion: Mini PCNL is a reliable option to standard PCNL with comparable effectiveness and safety.

Division of Urology, Department of Surgery, Queen Mary Hospital, Hong Kong SAR

Aim: Minimally Invasive Surgical Therapies (MIST) such as water vapour thermal therapy (WVTT) and prostatic urethra lift (PUL) are treatment options for benign prostatic hyperplasia. This is a retrospective study to compare the early clinical outcomes of patients undergoing WVTT and PUL at our center.

Methods: Patients with prostate sizes from 30 to 80 cc who underwent WVTT or PUL between January 2020 and December 2023 in Queen Mary Hospital and Tung Wah Hospital were reviewed. Retreatment is defined as further BPH treatment such as restarting medication or receiving surgical management. Patient demographics, complications and early clinical outcomes were analysed.

Results: 85 patients (median age 67 years old) were enrolled. 57 patients (67.1%) underwent WVTT and 28 (32.9%) had PUL, with average follow-up times of 12.9 and 16.9 months, respectively. No significant difference in complications rate (14.3% vs. 10.7%, p = .744) and length of hospital stay (0.36 ± 0.989 vs. 0.73 ± 0.447 days, p = .065) was noted. Overall re-treatment rate was 24.6% in WVTT and 46.4% in PUL (p-value = .051). Surgical retreatment rate was 3.5% and 14.3%, with all of these occurred more than 1 year postoperatively. 42 patients who had reached 1 year post operation and were not lost to follow-up were included for subgroup analysis. One year retreatment-free rate was 33.3% in WVTT versus 40% in PUL (p-value = .746).

Conclusion: There was no clinically significant difference between WWVT and PUL in terms of early clinical outcomes. Retreatment was not uncommon, and patients should be thoroughly counselled preoperatively.

Division of Urology, Department of Surgery, United Christian Hospital, Hong Kong SAR

Aim: In this study, we recruited patients with ED who were prescribed PDE5i and evaluated their drug use pattern. We examined their socio-economic background to determine if drug intake frequency and adherence correlated with socio-economic factors.

Method: This is a cross-sectional, multi-center study involving two local HA hospitals. Eligible subjects were interviewed on telephone, and they were asked questions regarding their socio-economic background and use of PDE5i. Questions regarding sexual habit and their comments on PDE5i were also asked.

Results: From July 2021 to June 2022, 57 patients were enrolled. The majority of our patients were aged 61 or above, and most of them were retired or had a lower monthly income. Almost 50% of all participants had not engaged in sexual activity in the previous 3 months. In addition, they had poor PDE5i adherence. There was no statistically significant correlation between the frequency of PDE5i use and monthly income (p = .620), educational level (p = .382), or housing (p = .681) status. The overall effectiveness of PDE5i was modest in this study cohort, with only 12.3% of patients experiencing no ED after treatment. There was no relationship between age or smoking status and the effectiveness of PDE5i (p = .122 and p = .774 respectively). The majority of them (57.9%) had no after-PDE5i side effects. The cost of the medication, its lack of efficacy, and a decline in sexual interest were the main reasons for not utilizing PDE5i.

Conclusion: There was no demonstrable relationship between socio-economic status and PDE5i use.

Division of Urology, Department of Surgery, Queen Mary Hospital, Hong Kong SAR

Aim: To compare the incidence of infection after prophylactic Ciprofloxacin plus Metronidazole combination (CM) and Amoxicillin plus Clavulanic Acid (Augmentin) monotherapy in patients undergoing transrectal ultrasound guided prostate biopsy (TRUS biopsy).

Method: This is a multicenter retrospective review of patients from August 2022 to May 2023 who underwent TRUS biopsy. The primary outcome is the rate of pooled infectious complications (including all types of infectious complications, i.e. fever, sepsis, symptomatic UTI) with prophylactic CM or Augmentin monotherapy. Secondary outcomes include the causative organisms and their antibiotic sensitivity.

Results: Twenty-four out of 121 patients with prophylactic CM and 29 out of 84 patients with Augmentin monotherapy developed infectious complications after TRUS biopsy (19.8% vs. 34.5%, p = .023). Among the 53 patients who had post TRUS biopsy infection, 16 had positive blood or urine cultures (8 with prophylactic CM and 8 with Augmentin monotherapy), the causative organisms being Escherichia coli (n = 12), Klebsiella pneumoniae (n = 2) and Enterobacter species (n = 2). Out of the 16 cases, 11 (69%) were sensitive towards Augmentin; 8 of these patients received prophylactic CM, and the remaining 3 patients received prophylactic Augmentin monotherapy. Of 7 cases tested for sensitivity to fluoroquinolone, only 2 (29%) of them were susceptible to either ciprofloxacin or levofloxacin.

Conclusion: Compared to Augmentin monotherapy, prophylactic CM therapy results in fewer infectious complications post TRUS biopsy. Although most causative organisms are sensitive towards Augmentin, some patients still develop infection despite Augmentin monotherapy. Thus, a multidrug prophylactic regimen is recommended, with Augmentin being one of the agents.

Department of Surgery, The 1st Affiliated Hospital of School of Medicine, Zhejiang University, School of Medicine, China

Aim: To propose a contrastive language-image pretraining (CLIP)-driven model to predict stent failure for malignant ureteral obstruction (MUO) in patients with non-urological malignancies.

Method: A total of 158 patients with 208 stent placements from two hospitals were included. Visual features were extracted using pretreatment CT images by UNETR. Textual features were extracted using patients' clinical characteristics by BioBERT. The CLIP framework was employed to train an image-text matching model through a local feature alignment network. After the visual and textual features being matched by the matching model, the data would be put into a multilayer perceptron for classification. XGboost algorithm was employed as the classifier.

Results: The proposed model achieved an accuracy of 0.83. Heatmap constructed by the Gradient-weighted Class Activation Mapping revealed that the renal pelvis areas were the important regions in relation to stent placement failure.

Conclusion: This study demonstrated that the CLIP-driven model can potentially help clinicians to select proper MUO patients for stent placement.

Department of Surgery, Kwong Wah Hospital, Hong Kong SAR

Aim: The development of percutaneous ablation therapy for small renal tumours including radiofrequency ablation (RFA) and cryoablation has been evaluated in recent years. It provides a possible alternative treatment that is less invasive, in comparison to the mainstay treatment of partial nephrectomy.

Method: A retrospective comparative study was conducted to review patients who were treated with ablation therapy between June 2021 to July 2023 in Kwong Wah Hospital. Patients' demographic details and baseline tumour characteristics were reviewed. Postprocedural outcomes and presence of urological and nonurological complications were evaluated.

Results: Clinical outcomes of 18 lesions in 17 patients were reviewed (mean age 65.75 ± 11.11), of which 9 underwent RFA and 8 underwent cryoablation. RENAL score were calculated, ranging from 5 to 10 (mean 7.55 ± 1.54). In view of affecting the interpretation of ablation zone, 59% patients underwent same session biopsy along with ablative therapy, with 40% biopsy result showing malignancy and 30% of patients' specimen was insufficient for diagnosis. Two patients showed incomplete ablation of renal tumour in reassessment scan requiring repeat ablation, otherwise no recurrence were observed. Majority of patients did not experience complications, the most common included postprocedural hematoma which occurred in 4 patients and urinary tract infection in 3 patients. No significant difference was noted between patients who underwent RFA and cryoablation, with regards to the baseline characteristics, outcome, and complications.

Conclusion: Ablation therapy shows to be a safe alternative method for treatment of small renal tumours. Additional studies in extended period are required to evaluate its long-term oncological effectiveness.

Division of Urology, Department of Surgery, Queen Mary Hospital, Hong Kong SAR

Aim: Infection after percutaneous nephrolithotomy (PCNL) is common. Administration of prophylactic antibiotics is recommended in current guidelines. However, there is limited evidence on the duration of prophylactic antibiotics. This study aims to examine the relationship between the use and duration of prophylactic antibiotics and the risk of post-operative infection.

Methods: Patients underwent PCNL in Queen Mary Hospital and Tung Wah Hospital from 1st January 2007 to 31st March 2023 were included. Baseline characteristics, preoperative urine culture, duration and type of prophylactic antibiotics were examined. Post-operative outcomes including fever, sepsis, and length of stay were analysed.

Results: A total of 435 patients were included with mean age of 55.7 ± 11.0 years old. A dose of intravenous antibiotic on induction was given to all patients. Twenty-seven percent (N = 119) of them had positive preoperative urine culture. The most common pathogens were Escherichia coli (27.4%) and Proteus (25.6%). Positive culture demonstrated a higher postoperative fever rate, more ICU/HDU admissions and longer length of stay. In patients with negative culture, 178 patients were given antibiotics on induction only and 138 patients were given an extended course of preoperative antibiotics of 7.3 ± 2.3 days. There were no significant differences in postoperative fever (17.5% vs. 11.6%, p = .155) and sepsis rates (3.9% vs. 2.9%, p = .762). The ICU/HDU admission rates and the post-op duration of antibiotics were also comparable. However, the extended course group showed shorter length of stay (6.5 ± 3.7 vs. 5.2 ± 2.3 days, p < .001).

Conclusion: An extended course of prophylactic antibiotics does not show additional benefit in prevention of infection.

Division of Urology, Department of Surgery, Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR

Aim: To evaluate risk stratification tools in predicting outcomes of ultrasound MRI fusion biopsy in patients with PIRADS 3 or above lesions on multiparametric-MRI.

Method: A retrospective review was performed on 230 patients who underwent transperineal ultrasound MRI fusion biopsy for lesions marked PIRADS 3 or above. A biopsy result of ISUP ≥2 was considered as clinically significant prostate cancer (csPCa).

Results: 230 patients comprising a total of 370 lesions were reviewed. Among this cohort, the prevalence of clinically significant prostate cancer (csPCa) is 25% (58/230) and the cancer detection rate of csPCa in patients with solely PIRADS 3 lesions was 8% (7/92). The multivariate analysis revealed that age, PIRADS score, prostate health index (PHI) and PSA density (PSAD) were independent predictors for csPCa. In patients with solely PIRADS 3 lesions, no patient was found to have csPCa if PHI was less than 35 and the prevalence of csPCa was only 5% if PSAD was less than 0.15. Our analyses of prostate cancer localization revealed a significantly less rate of cancer detection of PIRADS 3 lesions in base region in compared with midgland (OR 0.32, p < .05) and apex regions (OR 0.07, p < .05), and no difference was seen in PIRADS 4–5 lesions.

Conclusion: Patients with solely PIRADS 3 lesions have low likelihood of csPCa. A combination of PIRADS score and PSAD or PHI categories can help in risk stratification in prostate biopsy. PIRADS 3 lesions at prostate base have lower prostate cancer detection compared to other regions.