Abstract
Purpose :
To determine the anatomical and functional correlates of intraretinal cysts in retinitis pigmentosa.
Methods :
One hundred three patients (196 eyes) with untreated cystoid macular edema (CME) were identified from a pool of 578 genotyped patients with retinitis pigmentosa. Three central horizontal OCT scans were used to calculate the size of the retinal nerve fiber layer, outer retinal, inner retinal area, cysts, and total retinal areas. Ellipsoid zone and outer limiting membrane lengths were also measured. Best-fit curves were used to analyze the factors that play a role in the size of the retinal cysts and the patient’s visual acuity. Correlations between the visual acuity, morphometric and clinical data were sought.
Results :
Twenty-five percent of the screened patients (103/578) had CME. Patients with autosomal dominant retinitis pigmentosa had the highest incidence of CME (43.6%, p<0.001) but also had the best visual acuity (20/34±20/30, p=0.02). The total cyst area was 0.14±0.18 mm2. Outer retinal area (B=0.214; p=0.008), age (B=-0.003; p<0.001) and retinal nerve fiber area (B=0.411; p=0.005) were main determinants of the (r=0.44; p<0.001) cyst size. Cysts resolved with progressing retinal degeneration. Length of the intact ellipsoid zone (B=-5.16E-5; p<0.001), the inheritance pattern (B=0.04; p=0.028) and retinal nerve fiber area (B=0.751; p<0.001) were the main determinants of visual acuity.
Conclusions :
Retinal nerve fiber layer emerges as a significant morphologic parameter correlating with the intraretinal cyst size and decreasing visual acuity. This finding suggests axonal compression and subsequent visual loss as a possible complication of intraretinal cysts in retinitis pigmentosa.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.