Abstract
Purpose :
To quantify by means of angio-OCT blood flow (BF) in the superfical (SCP) and deep capillary plexus (DCP) of eyes affected by idiopathic epiretinal membrane (iERM) and to assess correlation with focal light sensitivity (FLS) evaluated by microperimetry
Methods :
Seven eyes of 7 patients with iERM, mean age 68.89±2.97 years, 4 F and 3 M, were studied. All subjects had ametropia <3D and underwent clinical examination including VA evaluation using ETDRS chart and slit-lamp biomicroscopy with +90D lens. The macula was analyzed with the SS angio-OCT Plex Elite 9000 (Carl Zeiss Meditec, Inc. Dublin CA) using Cube 1024x1024 scan to confirm the diagnosis and Angio 3x3 scan to evaluate the BF in the SCP and DCP. The software Macular Density v0.6.1 (beta release, Zeiss Algorithm Development, ARI Network), produced binarized images of the 2 plexuses, the software ImageJ (ver. 1.50e, NIH, USA) was used to quantify the BF in a 150 mm radius area around each point analyzed by MAIA microperimeter (Centervue S.p.A.,Padova, Italy). The eccentricity of the 24 points analyzed in each eye was between 2.5° and 5°, the inner 1° was not included for its location on the border of the FAZ. The Pearson correlation coefficent of BF (pixels) vs. retinal sensitivity (dB) in each point was calculated. A level of p<0.05 was accepted as statistically significant
Results :
In 5 of 7 eyes visual evidence of focal rarefaction of the capillary network in the macular plexuses corresponding to points of reduced FLS was found. The R for SCP was significant in 1 case (#2 R=0.41p=0.04) and in 3 cases for DCP (#2 R=0.49 p=0.01; #5 R=0.63 p=0.001; #7 R=0,39 p=0.05). Correlation was stronger in eyes with more points of reduced FLS, in which retinal folds were more evident and capillary networks more involved. The correlation between BF and FLS was higher for the DCP than SCP
Conclusions :
Alteration of BF in points of reduced FLS has been found in both SCP and, more frequently, in the DCP. As these defective areas were located mainly in sites of distortion of retinal layers and, therefore, of capillary plexuses, it can be hypothesized that the consequent focal reduction of BF, occurring mainly in DCP, could be involved in the onset of the functional defect
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.