In this Italian study, researchers investigated the subbasal corneal plexus (SCP) in patients with diabetic retinopathy (DR) treated or nontreated with panretinal Argon laser photocoagulation (ALP) and found that DR may induce substantial changes in the SCP.

A total of 50 consecutive patients with DR and 50 age– and sex–matched normal control subjects were examined with retinal tomography by a masked evaluator. The researchers considered the following subbasal plexus nerves parameters: number per frame, tortuosity and reflectivity. They divided diabetic patients into two groups according to the presence of proliferative versus nonproliferative retinopathy, according to the Early Treatment of Diabetic Retinopathy Study (ETDRS) classification.

According to the study researchers, the number of fibers per frame and reflectivity were significantly lower in diabetic patients compared with control subjects (2.4 ± 1 vs. 2.9 ± 0.8, p=0.01 and 2.3 ± 0.9 vs. 2.6 ± 0.9, p=0.04, respectively) Tortuosity was significantly higher in diabetic patients (2.5 ± 0.9 vs. 2.0 ± 0.8, p=0.002). The researchers noted that number per frame and reflectivity were significantly lower in diabetic patients with proliferative diabetic retinopathy (PDR; respectively, 2.0 ± 0.9 vs. 2.9 ± 0.9, p=0.001, and 2.0 ± 0.8 vs. 2.6 ± 0.7, p=0.003). Tortuosity was significantly higher in the PDR group (2.2 ± 0.8 vs. 2.8 ± 0.9, p=0.008) and furthermore, the PDR group treated with ALP had significantly lower subbasal nerves numbers compared with the nontreated group (p=0.01).

There is a difference between proliferative and nonproliferative retinopathy and in the former group between ALP treated and nontreated patients.

This interventional, non–comparative case series assessed the outcome of intravitreal pan-antivascular endothelial growth factor (VEGF) agents in eyes with persistent or reactivated choroidal neovascularization (CNV) following previous treatment with photodynamic therapy (PDT).

Baseline assessments including best–corrected visual acuity, fluorescein angiography (FFA) and optical coherent tomography (OCT) were performed and intravitreal ranibizumab and/or bevacizumab were administered on a PRN basis, guided by changes in visual outcome and OCT findings. The follow–up period was at least 6 months.

It was noted that 25 subjects with predominantly classic CNV, previously treated with PDT (mean 1.84 PDT sessions) showed reactivation or persistent CNV. The mean interval between PDT and intravitreal anti–VEGF treatment was 18.32 months (1–48 months); and patients received an average of 3.2 injections over a 6–month period. The mean change of visual acuity following PDT was –10.12 Early Treatment Diabetic Retinopathy Study (ETDRS) letters (54.3615.79–44.2417.32 letters). Additionally, it was reported that following anti–VEGF therapy, the mean change in visual acuity at 3 and 6 months were +1.76 and +0.72, respectively. The proportion of subjects with stable vision (loss of 15 letters) was 96% at 3 months and 88% at 6 months; the proportion of subjects who showed improved vision (15 letters) was 8% at 3 months and 4% at 6 months.

Anti–VEGF agents stabilized the visual outcomes of eyes previously treated with PDT, it was concluded. However, the proportion of patients who showed improved vision in this group was smaller than the proportion reported in subjects with treatment–naïve lesions.