Choroidal Thickness in Diabetes and Diabetic Retinopathy: A Swept Source OCT Study

Abstract

Previous studies on the association between choroidal thickness (CT) and severity of diabetic retinopathy (DR) gave conflicting results. The aim of this study was to evaluate the CT changes in diabetic patients and associated factors in a large sample of Chinese patients with diabetes. METHODS. Type 2 diabetes mellitus patients without history of ocular treatment were recruited from the community health system in Guangzhou, China. The swept source OCT instrument was used to obtain high-definition retina and choroid images. The diabetic retinopathy (DR) status was graded based on the guidelines of the United Kingdom National Diabetic Eye Screening Programme. Univariate and multivariate linear regression analyses was used to explore the association of CT with DR severity, diabetic macular edema (DME), hemoglobin A1c, and vision function. RESULTS. A total of 1347 patients were included in the final analysis. After adjusting for other factors, the patients with stage R3 DR had significantly thinner CT (β =-29.1 μm, 95% CI-53.8 to-4.4, P = 0.021) in comparison in those with R0. After adjusting for other factors, the CTs were thicker than those in R0 patients with difference of 15.6 μm (95% CI 4.3-26.9, P = 0.007) for outer nasal sector, 15.7 μm (95% CI 3.8-25.5, P = 0.008) for outer inferior, and 12.2 μm (95% CI 0.4-24.0, P = 0.042) for inner inferior sector. The presence of DME and hemoglobin A1c levels did not significantly affect average CT. Higher average CT was significantly associated with better best corrected visual acuity, with a-0.02 LogMAR unit per 100 μm increase in average CT (95% CI-0.03 to-0.01, P < 0.001). CONCLUSIONS. CT increased in the early stage of DR, and further decreased with DR progression. DME was not significantly associated with CT. These findings provide more clues to suggest that choroid alterations play a role in the pathogenesis of DR.

Analysis of the Choroid and Its Relationship with the Outer Retina in Patients with Diabetes Mellitus Using Binarization Techniques Based on Spectral-Domain Optical Coherence Tomography

“…Not least, the sympathetic innervation seems to be activated in early stages of DR, which increases choroidal thickness. However, as DR progresses and hypoxia gains ground, the choroid thins, suggesting a decrease in blood flow [ 14 , 41 ].…”

Long-Term Oral Treatment with Non-Hypoglycemic Dose of Glibenclamide Reduces Diabetic Retinopathy Damage in the Goto-KakizakiRat Model

“…Male GK rats develop late complications such as microangiopathy, nephropathy, neuropathy and retinopathy [ 25 ]. Although no animal model recapitulates all the features of human diabetic retinopathy, male GK rats develop progressive retinopathy with local inflammation, retinal circulatory abnormalities [ 26 ] and retinal edema [ 26 , 27 , 28 , 29 ], together with a thickening of the choroid [ 27 ], before microangiopathy develops at around 7 months [ 30 ], mimicking the kinetics of the events in human diabetic retina [ 31 ]. The retinopathy involves a PKCzetaoveractivation-linked blood–retinal barrier (BRB) breakdown, photoreceptor neurodegeneration [ 28 , 32 ], Müller cell swelling and morphological damage of the outer retina [ 21 ].…”

Evaluation of an Intravitreal Rho-Associated Kinase Inhibitor Depot Formulation in a Rat Model of Diabetic Retinopathy

“…This regulation is essential to control the blood flow in the choroid, where the autonomous neural system regulates the proper oxygen and nutrient supply to the photoreceptor cells. In diabetes, autonomic neuropathy [ 29 , 30 ] could contribute to choroid and outer retina pathology [ 31 , 32 , 33 , 34 ]. Since ROCK inhibition was shown to promote nerve regeneration [ 35 , 36 ] and the vascular effect of ROCK to act at least in part through sympathetic nerve-mediated ROCK activation [ 37 ], further studies could explore the effect of ROCK inhibition on choroidal neuropathy in diabetic conditions.…”