Discordance in Retinal and Choroidal Vascular Densities in Patients with Type 2 Diabetes Mellitus on Optical Coherence Tomography Angiography

Abstract

Purpose. In the present study, the retinal and choroidal vascular densities (VDs) in type 2 diabetes mellitus (DM) patients were analyzed using optical coherence tomography angiography (OCTA). Methods. The study included 282 eyes of 152 patients with type 2 DM (114 without retinopathy, 79 nonproliferative diabetic retinopathy (NPDR), 48 severe NPDR, and 41 proliferative diabetic retinopathy (PDR) eyes). The superficial and deep retinal vessel, choriocapillaris, and choroidal VDs were measured using a binarization method on OCTA images. VDs were compared based on retinopathy severity. Correlations among densities were analyzed. Results. Retinal and choriocapillaris VDs were lower in PDR than in NPDR (all P < 0.05 ). Correlation analysis showed significant positive correlations among densities of superficial and deep retinal vessels and choriocapillaris (all P < 0.001 ). Choroidal VD showed a negative correlation with superficial and deep retinal vessels and choriocapillaris (all P < 0.001 ). Retinal and choriocapillaris VDs showed a negative correlation with diabetic retinopathy (DR) grade (all P < 0.001 ); however, the choroidal VD showed a weak positive correlation ( P = 0.030 ). Conclusion. Choroidal VD increased as retinal and choriocapillaris VDs decreased, indicating that the outer layer of the choroid is less affected by DR severity and VD of larger choroidal vessels may even be increased as a compensatory mechanism for decreased retinal and choriocapillaris VDs in type 2 DM patients.

Choroidal changes in patients with diabetic retinopathy

“…The relationship between the choriocapillaris and retinal vascular plexus is another issue that is not well understood. Reviewing previous reports, most of them included patients with DR of all severities and reported that both retinal capillary plexus density and choriocapillaris density decreased along with more severe DR [9,10,[28][29][30]. According to the report of Lupidi et al [11], choriocapillaris vascular perfusion density (VPD) was negatively correlated with deep capillary plexus VPD of the retina in low-grade DR.…”

“…Choriocapillaris ow was found to be decreased in DR patients [9,10]. However, there are limited data on the relationship between choriocapillaris ow and other parameters, such as retinal vascular density and CTh.…”

“…Several previous studies have reported that choroidal changes in diabetic patients might have an important role in the development of DR. [1][2][3][4] With the advancements in optical coherence tomography (OCT) technology, previous studies have demonstrated several choroidal changes associated with DR. These choroidal changes included choroidal thickness (CTh) [5][6][7][8], choroidal vascular index (CVI) [9][10][11][12] and choriocapillaris ow. Unfortunately, there were con icting results on diabetic choroidal changes according to previous studies.…”

Choroidal Changes in Patients with Diabetic Retinopathy: A Retrospective Study

“…With advancements in optical coherence tomography (OCT), previous studies have demonstrated several choroidal changes associated with DR. These include changes in choroidal thickness (CTh) [ 5 , 6 , 7 , 8 ], choroidal vascular index (CVI) [ 9 , 10 , 11 , 12 ], and choriocapillaris flow. However, previous studies have reported conflicting results regarding diabetic choroidal changes.…”

“…Choriocapillaris flow is decreased in patients with DR [ 9 , 10 ]. However, there are limited data on the relationship between choriocapillaris flow and other parameters such as retinal vascular density and CTh.…”