Best Vitelliform Macular Dystrophy.

Area of Science:

• Ophthalmology
• Genetics
• Retinal Diseases

Background:

• Autosomal recessive bestrophinopathy (ARB) arises from a total absence of functional bestrophin-1 protein.
• This genetic condition is caused by mutations in the BEST1 gene on both chromosomes.

Purpose of the Study:

• To describe the clinical presentation and diagnostic features of Autosomal recessive bestrophinopathy (ARB).

Main Methods:

• Clinical examination of patients with ARB.
• Optical coherence tomography (OCT) for retinal imaging.
• Fundus autofluorescence (FAF) to assess retinal pigment epithelium (RPE) status.
• Electroretinography (ERG) to evaluate photoreceptor function.
• Electrooculography (EOG) to assess RPE function.

Main Results:

• Early-onset ARB may present with decreased vision and amblyopia.
• Common findings include hyperopia, predisposing to acute angle-closure glaucoma.
• Distinctive yellowish, multifocal lesions, larger and more extensive than in dominant Best disease, are observed.
• Subretinal fibrosis in the macula, cystoid changes on OCT, increased FAF (lipofuscin accumulation), and decreased FAF (RPE atrophy) are noted.
• Progressive panretinal photoreceptor dysfunction is indicated by delayed rod and cone responses on full-field ERG.
• Abnormal Arden ratio on EOG signifies RPE dysfunction.

Conclusions:

• ARB presents with unique clinical and imaging findings.
• Comprehensive ophthalmological evaluation including OCT, FAF, ERG, and EOG is crucial for diagnosis.
• Understanding these features aids in differentiating ARB from other retinal dystrophies.