Analysis of Changes in Retinal Thickness in Type 2 Diabetes without Diabetic Retinopathy

Abstract

Objective To examine the changes in retinal thickness of patients with diabetes without DR. Designs A randomization, crossover, retrospective practice. Participants 43 diabetic patients and 43 ethnic-, age-, and sex-matched controls. Methods Full retinal thicknesses of ten areas were assessed using spectral domain optical coherence tomography. Confounding variables, such as age, gender, and glycated haemoglobin (HbA1c) level, were assessed by regression analysis. Main Outcome Measures Mean retinal thickness of ten areas. Results The mean thickness of the fovea was 215.8 ± 18.9 μm in the diabetes group and 222.0 ± 18.6 μm in the control group (p = 0.04). The mean thickness of the temporal parafovea was 319.9 ± 16.7 μm in the diabetes group and 326.0 ± 14.4 μm in the control group (p = 0.01). The mean thickness of the temporal perifovea was 276.4 ± 27.9 μm in the diabetes group and 284.8 ± 17.4 μm in the control group (p = 0.02). There were no significant differences in retinal thickness between groups in other areas (p > 0.05). Regression analysis revealed that decreased retinal thickness of the temporal perifovea was associated with a higher HbA1c level (>8.7%) (p = 0.04). Conclusion and Relevance Subtle structural changes in the retina may occur in diabetes without DR. Decreased retinal thickness appeared to begin in the fovea and temporal areas. A high HbA1c level was the main factor influencing retinal thickness.

Protective Effect of Palm Oil-Derived Tocotrienol-Rich Fraction Against Retinal Neurodegenerative Changes in Rats with Streptozotocin-Induced Diabetic Retinopathy

“…Therefore, at an early stage of DR, reduced RLT may be an important morphological change, indicating neurodegeneration. In fact, such changes in diabetic retinas have been detected by optical coherence tomography (OCT) [33]. In accordance with these observations, in the current study, we observed greater retinal cell apoptosis, consequently causing significant thinning of various layers of the retina in STZ-induced diabetic rats compared to normal rats.…”

Thinning of Macular Neuroretinal Layers Contributes to Sleep Disorder in Patients With Type 2 Diabetes Without Clinical Evidences of Neuropathy and Retinopathy

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Within-subject assessment of foveal avascular zone enlargement in different stages of diabetic retinopathy using en face OCT reflectance and OCT angiography

“…Maximum macular thickness is found within the 3 mm diameter of the parafovea, while the thinnest retina is observed in the temporal retina decreasing gradually toward the periphery [51]. This relative thinness of temporal retina beyond the center 3 mm of the macula may contribute to greater vulnerability to ischemia and hence diabetic changes [52]. Wide-field fluorescein angiography appears to also support this increased susceptibility of the temporal midperipheral retina to diabetic changes.…”