Multimodal analysis of the progression of Best vitelliform macular dystrophy

To investigate the multimodal morphological features in the different stages of Best vitelliform macular dystrophy (VMD) in subjects harboring mutations in the BEST1 gene, and their changes during the progression of the disease.

In this retrospective observational study performed between January 2007 and December 2012, 21 patients (42 eyes) with Best VMD from eight families with the BEST1 mutation were included. Best-corrected visual acuity (BCVA), fundus autofluorescence (FAF), and spectral domain optical coherence tomography (SDOCT) were evaluated at study entry and at last visit.

The mean age of patients was 26.3±17.4 years. Seven new missense mutations in BEST1 were identified. Mean follow-up was 41.1±18.5 months. Mean BCVA was 0.34±0.34 LogMAR at study entry and 0.32±0.33 LogMAR at last follow-up visit (p = 0.2). The overall lesion area on FAF increased from 6.62±4.9 mm² to 7.34±6.1 mm² (p = 0.05). At study entry, on SD-OCT, photoreceptor inner segment ellipsoid portion (ellipsoid zone, EZ) was normal in 15 eyes, disrupted in 14 eyes, and absent in 13 eyes. In two eyes, EZ changed from normal to disrupted during follow-up. Three eyes of three patients showing pseudohypopyon lesions at study entry progressed to vitelliruptive lesions at the last follow-up visit. Three eyes of three patients showing vitelliruptive lesion at study entry reverted to pseudohypopyon lesion with overall enlargement of the lesion size.

Multimodal analysis allowed documenting a continuous material accumulation and reabsorption in Best VMD progression. Blue FAF and SD-OCT could represent noninvasive imaging techniques to monitor Best VMD.