Morphology and functional characteristics in adult vitelliform macular dystrophy

Purpose: Detailed morphologic and functional evaluation of adult vitelliform macular dystrophy (AVMD). Methods: The records of 61 consecutive AVMD patients (inclusion criterion: vitelliform lesion smaller than one disk diameter at least in one eye) were evaluated retrospectively regarding visual acuity, color vision, perimetry, retinal pigment epithelium (RPE) autofluorescence, fluorescein angiography, electro-oculography, full-field and multifocal electroretinography, and molecular genetic evaluation of the VMD2 and RDS/peripherin genes. Results: The mean age of subjects was 54.6 years. Visual loss was variable (median, 0.6; range, 1.25-0.05). Color vision and visual field were normal in about half of the patients but presented defects with high variability in the remaining patients. Autofluorescence findings showed increased fluorescence within the foveal yellow lesion in 76%. In the majority of eyes, the amplitude of the 30 Hz flicker response of the full-field electroretinogram (72%) and the central P1 amplitude of the multifocal electroretinogram (63%) were reduced. Mutational analyses revealed a potentially disease-associated mutation in the RDS/peripherin gene in one patient. Conclusion: AVMD is characterized by late onset, slow progression, good prognosis, and high variability of morphologic and functional abnormalities resulting frequently in misdiagnosis. Autofluorescence findings indicate lipofuscin accumulation in the yellow lesion. Electroretinography revealed a generalized cone system dysfunction with increasing severity toward the fovea.