Functional and Structural Analysis of the Central Retina According to the Fundus Autofluorescence Pattern in Patients with Retinitis Pigmentosa.

Background

This study evaluated morphological and functional differences among eyes with retinitis pigmentosa (RP) classified according to fundus autofluorescence (FAF) patterns.

Methods

A total of 146 eyes from 73 patients with RP were analysed. Based on FAF imaging, eyes were classified as having regular hyperautofluorescent rings (n = 23), irregular rings (n = 76), or absent rings (n = 47). Participants underwent best-corrected visual acuity (BCVA), contrast sensitivity, 10-2 and 30-2 static perimetry, multifocal electroretinography (mfERG), and optical coherence tomography (OCT). FAF morphometrics included ring diameters and area.

Results

Eyes with a regular FAF ring demonstrated significantly better visual function than those with irregular or absent rings, including higher BCVA (p < 0.001 and p = 0.001) and greater contrast sensitivity (both p < 0.001). The mfERG amplitude density in the first ring was higher in regular than irregular FAF patterns (p = 0.034). Eyes with irregular FAF showed more advanced visual field loss, with lower mean deviation on 10-2 (p = 0.042) and 30-2 perimetry (p = 0.027). In the regular-ring group, the ellipsoid zone was predominantly intact (p = 0.012). The hyperautofluorescent ring area correlated positively with mfERG amplitude density in the first and second rings (Rs = +0.573, p = 0.016; Rs = +0.736, p = 0.001) and with macular volume (Rs = +0.667, p = 0.003).

Conclusions

FAF patterns reflect central retinal functional and structural impairment in RP. Therefore, incorporating FAF imaging into the diagnostic algorithm is valuable for monitoring disease progression.