Patterns of Autofluorescence in Common Genotypes of Retinitis Pigmentosa.

BACKGROUND AND OBJECTIVE: To investigate whether different forms of retinitis pigmentosa (RP) could be distinguished from one another using fundus autofluorescence (FAF) imaging. PATIENTS AND METHODS: The National Institutes of Health EyeGene database was used to gather FAF images from 31 patients with RP, which were separated into 11 groups based on the RP-associated gene that was mutated. Investigators reviewed the images for patterns of autofluorescence (AF) and recorded qualitative observations. RESULTS: Four patterns of AF were noted within the macula, including central foveal hyper AF, a perifoveal hyper AF ring, a macular hyper AF ring, and a bull's-eye pattern of AF. Four patterns of AF were noted outside of the macula, including a mid-peripheral hyper AF ring, extramacular spots of hyper AF, patches of hypo AF, and diffuse hypo AF in the periphery. Double hyper AF rings were present in RHO, RPGR, USH2A, and NR2E3-linked RP. CONCLUSIONS: Similar patterns of AF were seen in different forms of RP, and AF failed to distinguish different genotypes. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:426-431.].

Autofluorescence of choroidal vessels in Bietti's crystalline dystrophy.

OBJECTIVE: To describe the pattern of fundus autofluorescence (FAF) in Bietti's crystalline dystrophy (BCD). METHODS AND ANALYSIS: From the National Institutes of Health EyeGene database of 2769 patients with known pathogenic mutations, 5 patients with BCD-causing CYP4V2 mutations who had FAF images were selected. Demographic and genetic information and imaging files were obtained. From the FAF imaging files, unique autofluorescence (AF) patterns and correlation with retinal structures were assessed by three investigators for clinical significance. RESULTS: Five patients (four males, one female; mean age 56 years, range 42-76 years) were included, all with different CYP4V2 mutations. All patients displayed varying degrees of hypo-AF in the posterior pole. In four out of five patients, there was a relative hyper-AF of choroidal vessels within the hypo-AF area; this feature was limited to sclerotic vessels only. A transitional zone of speckled AF was visible around the hypo-AF area. This zone corresponded to the area containing retinal crystals on colour fundus photography; however, retinal crystals did not demonstrate hyper or hypo-AF. CONCLUSIONS: This study presents a previously unreported characteristic finding in patients with BCD with CYP4V2 mutations. AF of choroidal vessels may aid in differentiating BCD from other retinal dystrophies.