1. Introduction

Stroke is the second leading cause of death, and Kim et al reported that stroke remained the third-leading cause of years-of-potential-life lost worldwide [1]. The stroke incidence ranged from 76 per 100,000 population per year up to 119 per 100,000 population per year in different countries [2], and it is expected that the incidence of stroke will continue to increase as the population ages [3]. There are about two million new patients of stroke annually in China [4]. Most of the stroke survivors are associated with functional disabilities in China [5], and motor dysfunction is the most significant symptom, which results in different levels of dysfunction (including muscle atrophy, joint stiffness, shoulder pain, deep vein thrombosis of the lower limb, long-term brakes, infection, anxiety, and depression) and disability in daily life. The stroke impact in China is more severe compared to the worldwide average levels. DALYs (disability adjusted life-years) caused by stroke rank 3rd in global epidemiologic study and first in China [6]. Overall poststroke care costs were the highest in the USA ($4850/per patient month) [7], which indicates that stroke not only brings pain to patients themselves but also imposes a great financial burden on families and communities in most countries, which has become a critical public health problem.

In 2002, the World Health Organization recommended acupuncture as a therapy for stroke [8]. Temporal three-needle acupuncture is one of Jin’s three-needle therapy systems created by Professor Jinrui in China. The temporal I needle is located on the hairline 2 cun above the apex of the ear; the temporal II needle and the temporal III needle are located 1 cun from the temporal I needle on either side in the horizontal direction [9]. Temporal three-needle therapy integrates the meridian acupoint theory in Chinese traditional medicine, modern neurological theory, and anatomical rationale [10, 11]. The location of the temporal three-needle is highly overlapped with the temporal bone seams, which is a crevice left by the congenital development process [12]. Additionally, the nerve is extended into the skull through the gap of the skull, which can effectively mobilize the neuron activity after acupuncture, and the position of the temporal three-needle ranged including the precentral gyrus and postcentral gyrus could widely affect the motor and sensory areas [13]. Meanwhile, the bioelectric effect of acupuncture at the location can be transmitted to the cerebral cortex, which can quickly rebuild the function of injured neurons in the functional area and strengthen the compensatory ability of the brain [11]. Moreover, the temporal bone is much thinner than other skulls, and its suture is mostly densest; acupuncture sensation is easier to be conducted, and the acupuncture effect is better. As a result, the acupoint selection of temporal three-needle has a certain representative. In real-world clinical practice, acupuncture on the left temporal three-needle treats right limb paralysis and acupuncture on the right temporal three-needle for the left paralysis, which is widely used in the poststroke rehabilitation in China [11, 14–18], especially motor dysfunction [14, 15, 19].

Because the study design is a superiority trial and stroke patients conventionally receive acupuncture at the scalp acupoint in current clinical practice in China, placebo (sham) stimulation or a blank control may violate the patient willingness. This trial will choose Dingnieqianxiexian (MS6) in the International Standardization Scheme for Scalp Acupuncture Points as the positive comparator in the control group. MS6 is an international standardized scalp acupoint, which refers to a diagonal line from Qianshencong (EX-HN1) to Xuanli (GB6) [20], and is projected to the precentral gyrus [21]; it is responsible for the autonomous movement of the limbs [20]. Studies have indicated that, on the basis of body acupuncture, temporal three-needle therapy is superior to acupuncture at MS6 with respect to daily life activities [22], motor function [22], and motor-related sensory disturbances [19].

However, the central mechanism of temporal three-needle therapy on stroke recovery remains unclear, especially in neuroimaging. From the last several years, with the rapid development of medical imaging technology, magnetic resonance imaging (MRI) has gradually become one of the main methods for studying the mechanism of acupuncture. Resting-state fMRI (rs-fMRI) only requires the subjects to stay still and close their eyes while scanning and keep their body as immobile as possible without thinking about anything. Rs-fMRI reflects intrinsic functional patterns and the spontaneous activity of the brain’s cortex [23], which is a useful technique for studying the mechanism of acupuncture [24]. In this trial, we plan to apply rs-fMRI to explore the central mechanism of temporal three-needle treatment.

Previous neuroimaging studies demonstrated that motor disorders in stroke patients were associated with functional connectivity (FC) abnormalities in the sensorimotor network or sensorimotor cortex [25, 26]. Moreover, functional recovery after stroke is associated with preserved FC of motor to nonmotor networks [27]. Acupuncture can increase the default mode network and sensorimotor network functional connectivity with pain-, affective-, and memory-related brain areas compared with sham acupuncture [24]. Several studies have also shown that acupuncture increases the sensorimotor network connectivity with pain-related brain regions in healthy adults or inhibits neuroinflammation in the sensorimotor cortex after ischemic stroke [28, 29]. However, the neuroimaging mechanism based on temporal three-needle therapy in hemiplegic patients with stroke remains unclear. The theoretical basis of scalp acupuncture is mainly based on the two aspects [20]: (1) the traditional Zangfu meridians theory and (2) scalp-cortex corresponding theory. According to the “scalp-cortex corresponding theory,” the temporal three-needle projects the cortex of the sensory area and the motor area on the temporal ear, and the bioelectric effect produced by acupuncture in this area is transmitted to the cerebral cortex, which can impact the function of the cerebral cortex [11]. Given the abovementioned viewpoints, we hypothesize that the underlying neuroimaging mechanism on neuromodulatory effects in temporal three-needle acupuncture may be related to sensorimotor network functional connectivity.

Therefore, our first objective is to assess the neuromodulatory effect of temporal three-needle therapy on resting-state regional brain activity, whole-brain activity, and motor function. Our second objective is to explore the relationship between alterations in functional connectivity at the sensorimotor network level and changes in behavioral performances to demonstrate the underlying neuroimaging mechanism of temporal three-needle treatment.

2. Methods

2.1. Study Design and Setting

This study will be a two-week, prospective, randomized, patient-assessor blind, controlled, single-center, superiority, neuroimaging trial with two-parallel patient groups and a healthy control group. This study will take place mainly in Shenzhen Nanshan District People’s Hospital, Shenzhen, Guangdong Province, China. In this trial, we will recruit subjects into two categories. The first category will comprise healthy controls, and the second will comprise patient subjects. A total of 20 age-, gender-, and education-matched healthy subjects will be recruited into the healthy control group. The purpose of healthy control recruitment is to establish a baseline normal MRI data set to facilitate comparison with the MRI data of the patients’ groups. The healthy control group will receive baseline MRI scans without any intervention. Forty eligible patients will be randomized into two groups: (1) the experimental group and (2) the control group, with a 1 : 1 allocation ratio. All patients will take medicine for secondary prevention of stroke (e.g., antihypertensive, hypoglycemic, antiplatelet, and hypolipidemic drugs) and conventional rehabilitative treatments according to the Chinese stroke rehabilitation treatment guidelines [5] (e.g., physical therapy (PT) and occupational therapy (OT)); these treatments will be consistent across the patient groups. In the control group, patients will receive acupuncture at MS6 following basic drug treatments and conventional rehabilitative treatments. Patients in the experimental group will receive temporal three-needle acupuncture 5 days per week, 10 sessions over 2 consecutive weeks, plus basic drug treatments and conventional rehabilitative treatments. Acupuncturists with at least 10 years of clinical experience will perform acupuncture therapy (including temporal three-needle therapy and MS6 therapy). Professional rehabilitative therapists with above 5 years of clinical experience will conduct conventional rehabilitative treatments (PT and OT) for the patients.

The planned flowchart of the trial is shown in Figure 1. The timeline for assessment is provided in Table 1. This study protocol is in compliance with the requirements of the Helsinki Declaration. Ethical approval was provided by the Ethics Committee of Shenzhen Nanshan District People’s Hospital in February 2018. In addition, Shenzhen Nanshan District People’s Hospital is also carrying out this trial and is responsible for the coordination of all departments’ activities (e.g., study protocol registry, staff training, informed consent implementation, and data management). This protocol follows Standard Protocol Item: Recommendations for Interventional Trials (SPIRIT) 2013 [30] (see Additional File 1 in Supplementary Materials available here) and the Consolidated Standards of Reporting Trials (CONSORT) 2010 statement for nonpharmacological interventions [31].

Table 1. Study schedule for enrollment, interventions, and assessments.

Study period
Items	Baseline		Treatment phase	Outcomes assessment
Time points	−1 to −3 days	0 weeks	1–2 weeks	3 weeks
Enrollment
Eligibility screen	×
Informed consent	×
Examination		×
Randomization		×
Intervention
Healthy control group (n = 20)
Experimental group (n = 20)			×
Control group (n = 20)			×
MRI scan
Healthy control group		×
Experimental group		×		×
Control group		×		×
Assessment (only in the experimental group and the control group)
FMA		×		×
MBI		×		×
Safety
Adverse events			×	×

2.7. Treatment

2.7.1. Basic Drug Treatment

Combined with their past stroke-related risk factors and current medical histories, all patients will receive secondary prophylactic drug treatment for stroke, including antihypertensive, hypoglycemic, antiplatelet, and hypolipidemic drugs.

2.7.2. Conventional Rehabilitative Interventions

Conventional rehabilitation treatment will be administered 5 days per week, 10 sessions (2 consecutive weeks):

• (a)

  Physical therapy [5]: PT will include active and passive activity of affected limb joint, neurodevelopmental therapy, balance function training, antispasmodic treatment, muscle strength training, and walking gait training.

• (b)

  Occupational therapy [5]: OT will include therapeutic activities for the upper limbs and hands of the affected side, activities of daily living, and training for the use of auxiliary equipment.

PT and OT will be performed by professional physiotherapists with at least 5 years of clinical experience. Each patient’s pre- and postrehabilitative intervention will be conducted by the same physiotherapist.

2.7.3. Experimental Group

The experimental group will receive acupuncture at temporal three-needle 5 times per week for 2 weeks following basic drug treatment and conventional rehabilitative treatment. The details of temporal three-needle therapy are presented in Table 2; the therapy will comply with the Standards for Reporting Interventions in Clinical Trials of Acupuncture (STRICTA) checklist [39].

Table 2. STRICTA checklist (details of intervention).

	Items	Details
(1) Acupuncture rationale	(1a) Style of acupuncture	Temporal three-needle therapy based on the rationale system of the meridian acupoint theory in Chinese traditional medicine, modern neurological theory, and anatomical rationale [10, 11]
	(1b) Reason for the treatment provided, based on the historical context, literature sources, and/or consensus methods, with references where appropriate	Acupoints to be used in this study were temporal three-needle located at the projection area of the sensory area and the motor area on the temporal ear [11]. Based on many previous studies, temporal three-needle therapy is widely used for stroke treatment in China [11, 14–18]
	(1c) Extent to which treatment was varied	Only the experimental group will receive temporal three-needle therapy
(2) Details of needling	(2a) Number of needle insertions per subject per session	3
	(2b) Names of points used	Temporal three-needle
	(2c) Depth of insertion, based on a specified unit of measurement	0.5 inches deep
	(2d) Response sought	“De Qi” sensation
	(2e) Needle stimulation	Manual operation
	(2f) Needle retention time	30 minutes
	(2g) Needle type	Sterilized stainless-steel needle measuring 0.30 × 25 mm (Huanqiu, Suzhou Acupuncture & Moxibustion Appliance Co., Ltd, Jiangsu Province, China)
(3) Treatment regimen	(3a) Numbers of treatment sessions	10 sessions (2 consecutive weeks)
	(3b) Frequency and duration of treatment sessions	30 minutes per day, 5 days per week
(4) Other components of treatment	(4a) Details of other interventions administered to the acupuncture group	All patients will receive basic drugs treatment and conventional rehabilitative treatments (including PT and OT)
	(4b) Setting and context of treatment, including instructions to practitioners and information and explanations to patients	The study will be conducted in Shenzhen Nanshan district People’s Hospital, and all information will be provided to the patients
(5) Practitioner background	(5) Description of participating acupuncturists	Acupuncturists after completing 5 years of Chinese medicine undergraduate course with more than 10 years of clinical experience will perform the temporal three-needle interventions
(6) Control or comparator interventions	(6a) Rationale for the control or comparator in the context of the research question, with sources that justify this choice	MS6 will be selected as the comparator in the control group based on traditional Chinese medicine theory
	(6b) Precise description of the control or comparator; if sham acupuncture or any other types of acupuncture-like control is used, provide details as for items 1 to 3 above	Based on previous studies [19, 22], MS6 will be mainly selected as the comparator for temporal three-needle therapy in motor dysfunction with stroke patients; in addition to the basic drug treatments and conventional rehabilitative treatment, only the control group will receive MS6 therapy; item 2 (details of needling) and item 3 (treatment regimen) are the same as the experimental group

The temporal I needle will be placed on the hairline 2 cun above the apex of the ear; the temporal II needle and temporal III needle will be placed 1 cun from the temporal I needle on either side in the horizontal direction [13] (Figure 2; the use of the picture has been allowed by the author Tongyan Liu and the patient). After routine disinfection of the scalp, disposable stainless-steel needles (0.30 × 25 mm) (Huanqiu, Suzhou Acupuncture & Moxibustion Appliance Co., Ltd., Jiangsu Province, China) will be manually inserted at each acupoint. After the acupuncturists insert needles into the acupoints at a certain depth and twist them for a while, patients report conscious sensations, such as soreness and numbness, in the acupuncture location, which indicates needle sensation “De Qi.” To treat motor dysfunction, the needles are rotated at 100 revolutions or more per minute for 1 minute at every 5 minutes over 30 minutes.

2.7.4. Control Group

The control group will receive acupuncture at the MS6 from Qianshencong (EX-HN1) to Xuanli (GB6) [20] following basic drug treatments and conventional rehabilitative treatments. The details of acupuncture at MS6 are presented in Table 2; this treatment will comply with the STRICTA checklist [39] as well.

3. Discussion

The similarities between the temporal three-needle and MS6 are as follows: (1) the two are both locating on the side of the skull and (2) the temporal three-needle and MS6 can treat contralateral central motor dysfunction [11, 20]. The differences between the temporal three-needle and MS6 are as follows: (1) the acupoint projecting brain regions are different: the temporal three-needle projects the sensory region and the motor region including the precentral gyrus and the postcentral gyrus, which may be responsible for sensory function and motor function of the limbs [13], and MS6 projects the precentral gyrus [21], which manages autonomous limb movement [20]; (2) the acupoint-related meridians are different: the temporal three-needle connects the Gallbladder Meridian of Foot-Shaoyang (GB), Bladder Meridian of Foot-Taiyang (BL), Stomach Meridian of Foot-Yangming (ST), and Sanjiao Meridian of Hand-Shaoyang (SJ); MS6 connects the Du meridian (DU), BL, and GB; (3) the acupoint stimulation sensation is different: the temporal three-needle is located at the temporal sutures which have a high degree overlap, and the gaps left by this congenital development process can help the needle sensation of the extracranial scalp penetrate deeper into the skull [10, 11, 13]; however, the MS6 stimulation location includes the parietal bone, frontal bone, and temporal bone, which are not the thinnest part of the skull, so the transmission of the acupuncture sensation may be weaker than that of the temporal three-needle. In summary, because of its different projected cortex, diverse-related meridian system, deeper stimulation sensation, and wider dysfunctional treatment (the temporal three-needle focuses on both motor dysfunction and sensory dysfunction), temporal three-needle therapy is now more widely used for ischemic stroke in China.

Studies have found that abnormal brain structures and functions exist in patients after stroke compared with age- and gender-matched healthy controls [53, 54]. In this trial, we will aim to investigate the neuromodulatory effect of sensorimotor network FC of temporal three-needle therapy for ischemic stroke patients with motor dysfunction. First, we will compare the differences in baseline rs-fMRI metrics between the healthy subjects and the stroke patients to confirm the difference between the healthy subjects and stroke patients. Second, to determine the difference due to the temporal three-needle treatment, we will compare the changes in the rs-fMRI metrics between the experimental group and the control group to demonstrate whether motor function alteration is related to brain functional neuroplastic changes after temporal three-needle treatment. Although a large number of studies on the use of temporal three-needle therapy for the treatment of motor dysfunction, speech disorders, dysphagia, and depression after stroke have indicated clinical behavioral effects [11, 14–18], to the best of our knowledge, our study will be the first randomized neuroimaging trial with both a positive control group and a healthy control group to examine the actual effects by means of rs-fMRI.

This study has several strengths. First, the implementation of rigorous randomized, patient-assessor blind, controlled, neuroimaging trial will provide visual and objective evidence about how temporal three-needle treatment improves motor dysfunction in ischemic stroke patients. Second, the combined assessments of rs-fMRI and behavioral data will be used to identify the neuromodulatory effects of temporal three-needle therapy in stroke patients. Third, research based on the FC within the sensorimotor network, and between the sensorimotor network and nonmotor network, is better for understanding the mechanism of temporal three-needle therapy in stroke according to the “scalp-cortex corresponding theory.”

Some limitations of this study should be noted. First, the major limitation of this protocol is its lack of long-term follow-up assessments. Second, there is no sham acupuncture or blank control comparison group for observation. Third, this trial will be conducted in a single center. Fourth, only the patients of left cerebral ischemia with right limb hemiplegia will be recruited in this protocol, and the patients of right cerebral ischemia with left limb hemiplegia will not be temporarily considered enrolled in this trial. We plan to resolve the aforementioned limitations in the future.

In conclusion, the results of this study are expected to explore the neuromodulatory effects and characterize the central mechanism of temporal three-needle treatment on motor dysfunction in hemiplegic stroke patients from the network-level viewpoint of sensorimotor network functional plasticity and to promote widespread application in real-world practice.

Additional Points

Recruitment began in March 2018 (Protocol version 1.0).

Ethical Approval

The study followed Helsinki Declarations. Ethical approval has already been obtained from the Ethics Committee of Shenzhen Nanshan District People’s Hospital (Approval no. 2018-0210-1).

Consent

All participants will understand the trial procedures and the trials’ purpose and potential benefits before they provide informed written consent.

Disclosure

Ning Zhao and Hong Zhang are co-first authors. The funding body had no role in the study design or the decision to submit the manuscript for publication.

Conflicts of Interest

The authors declare that they have no conflicts of interest.

Authors’ Contributions

Ning Zhao and Hong Zhang contributed equally to this work. NZ, HZ, and TYL drafted this manuscript. NZ supervised the blind implementation. TYL contributed the recruitment of the subjects. YX, GGS, and CZL contributed to outcomes assessment. JWX contributed to choosing the neuroimaging methods and conducting the statistical analyses. HZ, JL, and LDC revised the manuscript. LDC guided the protocol. All authors read and approved the final manuscript.