Changes of Sub-foveal choroidal thickness and choroidal volume in different stages of diabetic retinopathy through automated choroid segmentation method

Abstract

Purpose : To observe the changes in choroidal thickness and volume in type 2 diabetes patients with diabetic retinopathy (DR) through automated choroid segmentation method.

Methods : A total of 88 eyes from 64 type 2 diabetes patients were enrolled in this study. The patients included 29 males (32 eyes) and 35 females (56 eyes). The mean age was (62.7±7.4) years，and the mean diabetes duration was (13.7±7.2) years. All the patients were examined for best corrected visual acuity (BCVA), diopter, slit lamp ophthalmoscopy, indirect ophthalmoscopy and spectral domain optical coherence tomography (SD-OCT) examination. The patients were divided into non-DR (NDR group, 28 eyes), no-proliferative DR (PDR) without macular edema (ME) group (NPDR/ME- group, 36 eyes), PDR without ME group (PDR/ME- group, 24 eyes) according to the Early Treatment Diabetic Retinopathy Study. Age-matched normal subjects were enrolled as the Control group. Sub-foveal choroidal thickness (SFCT) and choroidal volume were measured through automated choroid segmentation method based on EDI-OCT images (SD-OCT with enhanced depth imaging) ¹.

1. Chen, Q., Fan, W., Niu, S., Shi, J., Shen, H. and Yuan, S. (2015). Automated choroid segmentation based on gradual intensity distance in HD-OCT images. Opt Express23, 8974-8994.

Results : Mean SFCT was (277.8±45.3), (220.9±38.7), (231.8±26.7), (252.0±42.2) μm respectively in Control, NDR, NPDR/ME- and PDR/ME- groups. Mean SFCT decreased significantly in NDR and NPDR/ME- group (P<0.05) compared with that in Control group. Mean SFCT in PDR/ME- group was thicker than that in NDR group (P<0.05). Mean choroidal volume was (8.8×10⁹±9.7×10⁸), (7.6×10⁹±1.3×10⁹), (8.2×10⁹±9.0×10⁸), (8.7×10⁹±9.5×10⁸) μm³respectively in Control, NDR, NPDR/ME- and PDR/ME- groups. Mean choroidal volume decreased significantly in NDR and NPDR/ME- group (P<0.05) compared with that in Control group. Mean choroidal volume in PDR/ME- group was thicker than that in NDR group (P<0.05).

Conclusions : SFCT and choroidal volume decreased during the early course of diabetics and increased significantly as the severity worsened from NDR to PDR.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.

 

General information

 

Sub-foveal choroidal thickness (SFCT) and choroidal volume of each group