Longitudinal Analysis of Functional and Structural Outcome Measures in PRPH2-Associated Retinal Dystrophy

Abstract

To establish disease progression rates in total lesion size (TLS), decreased autofluorescence (DAF) area, total macular volume (TMV), and mean macular sensitivity (MMS) in PRPH2-associated retinal dystrophy. Single-center, retrospective chart review. Patients with heterozygous pathogenic or likely pathogenic PRPH2 variants. Patients who underwent serial ultrawide-field (UWF) fundus autofluorescence (FAF), OCT, and Macular Integrity Assessment microperimetry with at least 1 year of follow-up were included. Linear correlation was performed in eyes of all patients to determine the rate of change over time. Outcome measures included changes in TLS, DAF area, TMV, and MMS. Twelve patients (mean age, 55) from 10 unrelated families attended 100 clinic visits, which spanned over a mean (SD) of 4.7 (2.0) years. Mean (SD) TLS and DAF radius expansion were 0.14 (0.12) and 0.10 (0.08) mm/year, respectively. Mean (SD) TMV change was-0.071 (0.040) mm3/year with no interocular difference (P= 0.20) and strong interocular correlation (r2= 0.88, P < 0.01). Mean (SD) MMS change was-0.10 (1.25) dB/year. Mean macular sensitivity declined in 4 and improved in 6 patients. Mean macular sensitivity was subnormal despite a TMV within the normal range. Serial measurements of UWF-FAF-derived TLS and DAF showed slow expansion. Total macular volume might be a more sensitive measure than MMS in detecting disease progression.