Vitreopapillary traction in nonarteritic anterior ischemic optic neuropathy

Purpose: To describe the association between vitreous traction on the optic disc and nonarteritic anterior ischemic optic neuropathy (NAION). Methods: Eighty three eyes of 83 patients with NAION were evaluated by optical coherence tomography (OCT) for detecting vitreous adhesion to the optic nerve head with separation from the adjacent retina (partial posterior vitreous detachment). Eyes which were negative for such adhesion underwent ultrasonography to detect complete posterior vitreous detachment (PVD). Results: Fifty male and 33 female subjects with mean age of 51.9±10 years were studied. Partial PVD with optic nerve head adhesion was found in 54 patients (65.1) using OCT. Ultrasonography detected complete PVD in all other eyes with optically empty spaces on OCT. Conclusion: Vitreous traction on the optic nerve head from partial PVD may play a causative role in some cases of NAION. This traction may impair vascular supply and/or axoplasmic flow leading to signs and symptoms of NAION

Two different doses of intravitreal bevacizumab for treatment of choroidal neovascularization associated with age-related macular degeneration

Purpose: To compare the efficacy and safety of 1.25 mg versus 2.5 mg intravitreal bevacizumab (IVB) for treatment of choroidal neovascularization (CNV) associated with agerelated macular degeneration (A). Methods: In this randomized clinical trial, consecutive patients with active CNV associated with A received 1.25 mg or 2.5 mg IVB. Best corrected visual acuity (BCVA), foveal thickness and side effects of therapy were evaluated one and three months after intervention. Results: Overall 86 subjects were enrolled and completed the scheduled follow-up. Forty seven and 39 patients received 1.25 and 2.5 mg IVB respectively. The study groups were balanced in terms of baseline characteristics such as age, BCVA and foveal thickness. Mean improvement in BCVA was 0.06±0.3 logMAR in the 1.25 mg group and 0.07±0.34 logMAR in the 2.5 mg group (P=0.9). Mean decrease in foveal thickness was 49±36 μm in the 1.25 mg group and 65±31μm in the 2.5 mg group (P=0.6). Three cases of vitreous reaction and one case of massive subretinal hemorrhage were observed in the 2.5 mg group. Conclusion: Double dose (2.5 mg) IVB does not seem to be more effective than regular dose (1.25 mg) injections for treatment of CNV due to A and may lead to more complications