AV Sheathotomy Reduces Risk Of Retinal Neovascularization

Abstract

 

Purpose:

 

To investigate the effect of pars plana vitrectomy with arteriovenous sheathotomy for branch retinal vein occlusion on subsequent retinal neovascularization and/or vitreous hemorrhage.

 

Methods:

 

A retrospective analysis was performed of 43 consecutive patients (13 male & 20 female) who underwent pars plana vitrectomy with arteriovenous sheathotomy by one of four surgeons at Retina Consultants of Alabama between April 2000 and July 2003. Data was collected from examinations at the following time points: pre–operative, at 1, 3, 6, and 12 months post operatively, and at last follow–up. Neovascularization and/or vitreous hemorrhage rates were compared to those published in the Branch Vein Occlusion Study (BVOS).

 

Results:

 

Mean age was 71 years. Duration of follow–up ranged from 3–31 months with a mean follow–up of 12 months. Retinal neovascularization was not identified in any of the 43 patients at any time point in the study. Vitreous hemorrhage was noted in 2 of the 43 patients in the immediate post–operative period, but was ascribed to intra–operative issues and not to retinal neovascularization. These rates were significantly lower than those published in the BVOS (p<0.0001).

 

Conclusions:

 

Par plana vitrectomy with arteriovenous sheathotomy for branch retinal vein occlusion significantly reduces the likelihood of developing subsequent retinal neovascularization and/or vitreous hemorrhage. Potential mechanisms for this effect include: 1) removal of the mechanical scaffold the vitreous normally provides for neovascularization, 2) improved retinal oxygenation, and\or 3) removal of the vitreous improves diffusion of angiogenic factors away from the retina.  

 

Keywords: vascular occlusion/vascular occlusive disease • neovascularization • retina