Paravascular Inner Retinal Defects Associated with Epiretinal Membranes

Abstract

Purpose : Paravascular inner retinal defects (PIRDs) along the temporal arcade vessels have been reported in eyes with epiretinal membranes (ERMs). We investigated the prevalence, detailed characteristics, and pathogenesis of PIRDs associated with ERMs.

Methods : In this prospective study, we included 81 eyes of 81 patients with idiopathic ERMs, without high myopia. The posterior pole was examined using optical coherence tomography (OCT) with the extended field imaging technique. The retinal structure surrounding the PIRDs was assessed using sequential thin sectioning. The PIRDs were classified into three grades. Typical defects of the inner retinal tissue were defined as grade 3. Inner retinal cleavages with openings to the vitreous cavity and no apparent defect of the inner retinal tissue were defined as grade 2. Inner retinal cleavages or cystoid spaces with no connection to the vitreous cavity were defined as grade 1. We evaluated morphological changes in the OCT sections and effects on the visual field based on the Goldmann perimeter.

Results : Of 81 eyes with ERMs, 31 (38.3%) had PIRDs along the temporal arcade vessels (grade 1 in 6 eyes, grade 2 in 4 eyes, and grade 3 in 21 eyes). On traverse OCT sections, the PIRDs typically appeared as cystoid or fissure-like spaces with or without the inner retinal surface. Longitudinal OCT sections revealed that PIRDs were frequently accompanied by broad defects of the inner retinal tissue (grade 3). On OCT sections, although some ERMs directly adhered to the edge of a PIRD or the retinal vessels, PIRDs were often located outside the area of adhesion to the ERM. Vitreous traction on the inner retina contributed to the progression of PIRDs. Visual field abnormalities corresponded to the location of the PIRDs in 16.7% of eyes with grade 1, 33.3% of eyes with grade 2, and 44.4% of eyes with grade 3 PIRDs.

Conclusions : Deviated retinal vessels due to the traction of the ERMs may contribute to the pathogenesis of PIRDs. PIRDs often cause visual field abnormalities corresponding to the location of the defect.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.