Heterogeneous choroidal thickness pattern in diabetic patients without diabetic retinopathy
Abstract
Purpose
The authors intend to present an analysis and comparison of the choroidal thickness in more distant superior regions. Choroidal thickness is increased in a heterogeneous pattern superiorly to the fovea in diabetic patients without diabetic retinopathy.
Methods
Observational case-control study of 60 eyes of 60 patients with diabetes mellitus type 2 without diabetic retinopathy. A control group of 31 eyes of 31 patients without diabetes with similar demographic features was also created. All the patients were recruited from the same outpatient clinic. Enhanced depth imaging spectral-domain optical coherence tomography (EDI SD-OCT SPECTRALIS®) was performed and high-resolution macular scans were obtained. Choroidal thickness was evaluated 2000 μm superiorly to the fovea by manual layer segmentation. Previous studies have validated the validity of using a manual layer segmentation procedure in OCT. Statistical analysis was done with SPSS Statistics. A p value <0.05 was considered statistically significant.
Results
Diabetic patients were in average 67.0 ± 9.6 years old and 56.7% were male. Average choroidal thickness 2000 μm superiorly to the fovea was 287.77 ± 74.32 μm in diabetic patients and 249.81 ± 53.96 μm in non-diabetic patients. There was a significant increase in choroidal thickness in diabetic patients when compared to non-diabetic patients (T-student, p = 0.014).
Conclusions
Choroidal thickness can be accurately measured using high-definition macular OCT scans. This study documented structural differences in the choroid associated with diabetes mellitus type 2 that are not only present in the central foveal area as reported in previous studies. Diabetes Mellitus is associated with multiple microvascular dysfunctions that are probably coupled with choroidal vascular modifications that induce changes in thickness.
