FAZ alterations after ILM peeling for ERM

Abstract

Purpose : We investigated the changes in foveal avascular zone (FAZ) area after vitrectomy with internal limiting membrane (ILM) peeling for epiretinal membrane (ERM).

Methods : This retrospective observational case series included 21 eyes of 21 patients (age: 68.4±6.5 years) who underwent vitrectomy with ILM peeling for ERM. Pre- and post-operative FAZ areas were measured using 3×3 mm superficial optical coherence tomography (OCT) angiography, and the relationship was investigated. In addition, the displacement distance of the centroid of FAZ was measured in OCT angiography images, and the association of the changes in FAZ area with pre-operative FAZ area, pre-operative foveal thickness, axial length, and the displacement distance of the centroid of FAZ were also investigated.

Results : Pre- and post-operative FAZ areas correlated significantly (p<0.001). Preoperative FAZ areas larger than 0.10 mm², were reduced after surgery and vice versa. The multivariate analysis showed that the changes in FAZ area were only associated with pre-operative FAZ area (p=0.001), and were not associated with other factors (all p>0.05).

Conclusions : Postoperative changes in FAZ area after ILM peeling only depended on baseline FAZ area. Because FAZ area of 0.10 mm² is much smaller than normal FAZ area, ILM may have centrifugal tractional forces on the fovea, and the FAZ area without the centrifugal tractional force of the ILM may be about 0.10 mm².

This is a 2021 ARVO Annual Meeting abstract.