Abstract
Purpose :
To date there are over 50 genes implicated in the pathogenesis of retinitis pigmentosa (RP). While specific patterns of fundus autofluorescence (FAF) have been reported in certain genotypes of RP, FAF patterns in RP still remain largely unknown. Our study analyzed FAF images from a large database to test the hypothesis that certain genotypes of RP have characteristic FAF patterns that may aid in clinical diagnosis.
Methods :
The NIH EyeGene database was used to gather FAF images, demographic information and genetic information from 45 patients with RP. FAF images were sorted based on genotype and were reviewed by multiple investigators for autofluorescence patterns. Qualitative observations were recorded. In total, 17 genotypes were studied—including BBS1, EYS, HK1, IMPDH1, KLHL7, NR2E3, PRPF3, PRPF8, PRPF31, TOPORS, RP1, RP2, CYP4V2, USH2A, RPGR, RHO, and PRPH2—all having either autosomal dominant, autosomal recessive or X-linked recessive patterns of inheritance.
Results :
No unique FAF patterns were observed in genes BBS1, EYS, HK1, IMPDH1, KLHL7, PRPF3, PRPF8, PRPF31, TOPORS, RP1, RP2, USH2A, RPGR, or PRPH2. Four out of six FAF images of CYP4V2-linked RP demonstrated a large area of hypoautofluorescence. Two out of seven FAF images of RHO-linked RP demonstrated a band of hyperautofluorescence in the mid-periphery, with one of these two images exhibiting a double hyperautofluorescent ring. The single FAF image of NR2E3-linked RP demonstrated a double hyperautofluorescent ring.
Conclusions :
Previous studies have described the double concentric hyperautofluorescent ring as a possible pathognomonic marker of NR2E3-linked RP. The presence of the double hyperautofluorescent ring in one out of seven patients with RHO-linked RP indicates that while it may not be a reliable phenotypic marker for RHO-linked RP, it is likely not pathognomonic for NR2E3 either. Ultimately, further large-scale analyses need to be conducted to better elucidate unique FAF patterns that may be of use in distinguishing between different forms of RP.
This is a 2020 ARVO Annual Meeting abstract.