Luke Nicholson

Diagnostic accuracy of disorganization of the retinal inner layers in detecting macular capillary non-perfusion in diabetic retinopathy.

Disorganization of the retinal inner layers (DRIL) on optical coherence tomography (OCT) is thought to represent retinal capillary non‐perfusion (CNP) in eyes with diabetic retinopathy. This study was designed to evaluate the ability of DRIL to accurately predict CNP.

Posterior Segment Distortion in Ultra-Widefield Imaging Compared to Conventional Modalities.

BACKGROUND AND OBJECTIVES To describe posterior segment distortions in Optos ultra-widefield images (Optos 200TX; Optos, Dunfermline, United Kingdom) compared to Topcon retinal camera images (Topcon, Tokyo, Japan) using optic disc dimensions and exploring a proposed method for correcting these distortions. PATIENTS AND METHODS Comparative image analysis study on 20 eyes with color fundus images from Optos and Topcon. A model eye with vertical and horizontal grids imaged with Optos in the conventional position and rotated 90° was analyzed. RESULTS Mean vertical-to-horizontal disc diameter ratios were 0.956 [95% CI, 0.919-0.993] for Optos and 1.083 [95% CI, 1.045-1.121] for Topcon (P < .001). This was 0.910 in the conventional position and 1.072 with the object rotated 90° for the model eye with Optos and 1.008 and 0.999, respectively, using Topcon. The average of the measurements taken using both images from Optos yielded a ratio of 0.987. CONCLUSION Optos incorporates a consistent horizontal stretch to images. Combining images taken at right angles reduces the distortion. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:644-651.].

Mechanistic Evaluation of Panretinal Photocoagulation Versus Aflibercept in Proliferative Diabetic Retinopathy: CLARITY Substudy

Purpose The purpose of this study was to study the effects of panretinal photocoagulation (PRP) and intravitreal aflibercept on retinal vessel oxygen saturations, area of retinal nonperfusion, and area of neovascularization in proliferative diabetic retinopathy. Methods This is a prospective randomized single center study. Forty patients with proliferative diabetic retinopathy were randomized to PRP or intravitreal aflibercept treatment for 52 weeks. Retinal oximetry and ultra-widefield angiography were performed at baseline and week 52. Ultra-widefield color fundus imaging was performed at baseline, week 12, and week 52. The outcomes were retinal arterio-venous oximetry differences (AVD), area of retinal nonperfusion, and area of neovascularization in disc areas (DA). Results The AVD in the PRP group increased from 36.7% at baseline to 39.7%, whereas it decreased from 33.4% to 32.5% in the aflibercept group. The difference in AVD between groups at week 52 was 4.0% (95% confidence interval, −0.08, 8.8; P = 0.10). The baseline mean area of retinal nonperfusion of 125.1 DA and 131.2 DA in the PRP and aflibercept groups increased to 156.1 DA and 158.4 DA, respectively, at week 52 (P = 0.46). The median baseline area of neovascularization decreased from 0.98 DA to 0.68 DA in the PRP group and from 0.70 DA to 0 DA in the aflibercept group at week 12 (P = 0.019). At week 52, this measured 0.24 DA in the PRP group and 0 DA in the aflibercept group (P = 0.45). Conclusions Intravitreal aflibercept achieved an earlier and complete regression of neovascularization in proliferative diabetic retinopathy compared with PRP. There were no significant differences in global change in intravascular oxygen saturation or areas of retinal nonperfusion between the two groups by 52 weeks.