Biofeedback Rehabilitation and Visual Cortex Response in Stargardt's Disease: A Randomized Controlled Trial.

Purpose: to evaluate the effect of biofeedback (BF) rehabilitation on the visual function and on the activity of primary visual cortex (PVC) in patients with Stargardt's disease owing to mutations in the ABCA4 gene (STGD1). Methods: This was a single-center, controlled, randomized study. Twenty-four patients with STGD1 were randomized into two groups: a treatment group (TG) undergoing BF rehabilitation and a control group (CG). Treatment with BF consisted of a 10-minute session per eye performed weekly for 12 weeks. The subjects underwent a baseline and 3-month follow-up visits, including best-corrected visual acuity (BCVA), reading test, microperimetry, and functional magnetic resonance imaging (fMRI). The fMRI studies were acquired sequentially using a passive viewing condition and an active reading task. The primary outcomes were the change in the fMRI activation of primary visual cortex and the change in reading ability. Results: After treatment, the patients in the TG were able to read smaller characters (P = 0.002) with a greater reading speed (P = 0.014) compared with patients in the CG. The fMRI studies showed a significant effect (P < 0.001) of BF on primary visual cortex activation in the TG compared with the CG. Finally, we observed significant (P < 0.05) improvements of best-corrected visual acuity, macular sensitivity, and fixation stability parameters in the TG compared with the CG. Conclusions: Our study showed that visual rehabilitation using BF improved the usage of residual visual function in patients with STGD1. Translational Relevance: Our findings show that the BF treatment compared with no treatment at all resulted in benefits. The specificity of the treatment could be examined to determine whether BF can be included in clinical practice.

AAV-mediated gene delivery of the calreticulin anti-angiogenic domain inhibits ocular neovascularization.

Ocular neovascularization is a common pathological feature in diabetic retinopathy and neovascular age-related macular degeneration that can lead to severe vision loss. We evaluated the therapeutic efficacy of a novel endogenous inhibitor of angiogenesis, the calreticulin anti-angiogenic domain (CAD180), and its functional 112-residue fragment, CAD-like peptide 112 (CAD112), delivered using a self-complementary adeno-associated virus serotype 2 (scAAV2) in rodent models of oxygen-induced retinopathy and laser-induced choroidal neovascularization. The expression of CAD180 and CAD112 was elevated in human umbilical vein endothelial cells transduced with scAAV2-CAD180 or scAAV2-CAD112, respectively, and both inhibited angiogenic activity in vitro. Intravitreal gene delivery of scAAV2-CAD180 or scAAV2-CAD112 significantly inhibited ischemia-induced retinal neovascularization in rat eyes (CAD180: 52.7% reduction; CAD112: 49.2% reduction) compared to scAAV2-mCherry, as measured in retinal flatmounts stained with isolectin B4. Moreover, the retinal structure and function were unaffected by scAAV2-CAD180 or scAAV2-CAD112, as measured by optical coherence tomography and electroretinography. Moreover, subretinal delivery of scAAV2-CAD180 or scAAV2-CAD112 significantly attenuated laser-induced choroidal neovascularization in mouse eyes compared to scAAV2-mCherry, as measured by fundus fluorescein angiography (CAD180: 62.4% reduction; CAD112: 57.5% reduction) and choroidal flatmounts (CAD180: 40.21% reduction; CAD112: 43.03% reduction). Gene delivery using scAAV2-CAD180 or scAAV2-CAD112 has significant potential as a therapeutic option for the management of ocular neovascularization.