Analysis of Fundus Autofluorescence in Patients With Different Genotypes and Phenotypes of Retinitis Pigmentosa (RP)

Purpose: to investigate the pattern of fundus autofluorescence and the correlation with the genotypes in a populationof 410 patients affected by different types of RP. Methods: Patientsselected from our RPdatabase, including 410 subjects with different types of RP,autosomaldominant,autosomal recessive, sporadic, mitochondrialand sindromic,were examinedfor analysis of the pattern of fundus autofluorescence (SLO-HRAHeidelberg). Ophthalmologicexaminationincluded refraction, best visual acuity at distance, slit lampexamination, fundoscopy, fundus photography, computerized perimetry (Humphrey),microperimetry(Nidek) color vision (Lanthony PanelD 15 test) dark adaptometry (Goldmann-Weekers)and electroretinography. Results: . All patients under examinationshowed a variably sized parafoveal ring of autofluorescence together with visual function and fundus changes typical of RP.In a number of cases a "negative" ring, with absence of autofluorescence, was observed. The size of autofluorescence ring is correlated with the size of residual central visual field, but not with the age of patients. The pattern of autofluorescence was not correlated with the genotype. Conclusions: A parafoveal ring of autofluorescence may represent a reliable diagnostic clinical parameter in RP,predicting the extent of photoreceptor degeneration in the the macular area.