Effect of 532 nm argon laser pan retinal photocoagulation on corneal thickness and corneal endothelial cell parameters among proliferative diabetic retinopathy patients

Purpose: To report the efficacy and safety profile of subthreshold pan-retinal photocoagulation (PRP) using endpoint management (EPM) algorithm compared with conventional threshold PASCAL PRP for the treatment of severe non-proliferative diabetic retinopathy (NPDR). Methods: This was a prospective, single center, paired randomized controlled trial of fifty-six eyes of twenty-eight participants with bilateral symmetric severe NPDR. One eye of the participant was randomly assigned to receive the subthreshold EPM PRP, while the other eye of the same participant received the threshold PASCAL PRP. The primary outcome measures included the difference in the one-year risk of progression to PDR between two groups, and mean changes of the logarithm of the minimal angle of resolution (logMAR) visual acuity (VA). The second outcome measures included central foveal thickness (CFT), one-year risk of progression to PDR, and visual field (VF) parameters. Results: The subthreshold EPM PRP group and the threshold PASCAL PRP group had similar one-year risk of progression to PDR during the 12-month follow-up visits (17.86% vs 14.29%, P>0.05). Slightly decreased VA was found in both groups (0.08 vs 0.09 logMAR VA), however, no statistical difference was found for neither group (P>0.05). Similar results were found for thickened CFT for both groups (23.59μm vs 28.34μm, P>0.05). Specifically, although substantial loss of VF was found in the threshold PASCAL PRP group (P<0.05), no obvious damage to VF was seen in the subthreshold EPM PRP group (P>0.05). Conclusion: The subthreshold EPM PRP is non-inferior to the conventional threshold PASCAL PRP in the treatment of severe NPDR during 12-month follow-up and could be an alternative treatment option for patients with severe NPDR.

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Effects of diabetes duration and HgA1C level on corneal endothelial morphology

European Journal of Ophthalmology ◽

10.1177/1120672120914812 ◽

2020 ◽

pp. 112067212091481

Author(s):

Salih Çolak ◽

Burcu Kazanci ◽

Dilek Ozçelik Soba ◽

Yasemin Ozdamar Erol ◽

Pelin Yilmazbas

Keyword(s):

Diabetes Mellitus ◽

Diabetic Retinopathy ◽

Endothelial Cell ◽

Standard Deviation ◽

Proliferative Diabetic Retinopathy ◽

Coefficient Of Variation ◽

Corneal Thickness ◽

Healthy Individuals ◽

Significant Difference ◽

Corneal Endothelial Cell Density

Objective: The aim of this study is to investigate the effects of the HbA1c level and the duration of diabetes mellitus on the corneal endothelium morphology and to compare between healthy individuals and diabetes mellitus patients with non-proliferative diabetic retinopathy and proliferative diabetic retinopathy. Material and methods: Ninety patients who applied to the Health Sciences University Ulucanlar Eye Training and Research Hospital between January 2016 and January 2017 were included in this prospective randomized study. In the study, 45 diabetes mellitus patients and 45 healthy individuals were evaluated. The diabetes patients were compared in terms of HbA1c level, diabetes mellitus duration, corneal endothelial cell density, coefficient of variation, standard deviation, and hexagonality with healthy control group. Results: A statistically significant difference was found in the endothelial cell densitometer, coefficient of variation, and standard deviation measurements between the diabetes mellitus patients and the control (healthy) group. But, there was no statistically significant difference between 6A (hexagonality) and central corneal thickness measurements. There was a negative correlation between HbA1c levels and diabetes mellitus times and endothelial cell densitometer values in the patients with diabetes mellitus diagnosis and standard deviation values in the positive direction. There was a statistically significant difference between diabetes mellitus patients with the diagnosis of non-proliferative diabetic retinopathy and proliferative diabetic retinopathy in the endothelial cell densitometer and standard deviation values. But there was not any statistically significant difference between coefficient of variation, 6A, and central corneal thickness values. Conclusion: The endothelial cell densitometer in diabetes mellitus patients with retinopathy is lower than that in healthy individuals. There is a negative correlation between retinopathy severity and corneal endothelial cell density. Diabetes affects negatively not only vascular tissues but also avascular cornea.

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