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.