---
title: How is Best disease diagnosed?
description: "Best disease (Best vitelliform macular dystrophy) is diagnosed using a combination of family history, characteristic macular appearance, and specialised retinal tests. It typically presents with a yellow \"egg‑yolk\" lesion at the macula in childhood or adolescence. ## Ophthalmic Evaluation Visual…"
url: "https://bluefinvision.com/knowledge-base/topics/diagnostics-testing/how-is-best-disease-diagnosed/"
updated: "2025-12-15"
category: "Diagnostics & Testing"
---

# How is Best disease diagnosed?

Best disease (Best vitelliform macular dystrophy) is diagnosed using a combination of family history, characteristic macular appearance, and specialised retinal tests. It typically presents with a yellow "egg‑yolk" lesion at the macula in childhood or adolescence.

## Ophthalmic Evaluation

Visual acuity testing and dilated fundus examination look for vitelliform lesions, atrophy, or scarring at the macula.

- OCT imaging shows subretinal deposits and helps stage the disease over time.
- Autofluorescence and fundus photography document the distribution and evolution of lesions.
- Both eyes are assessed because the condition is usually bilateral, though often asymmetric.
- Other macular disorders are excluded based on age, appearance, and test results.

## Electrophysiology and Genetics

Additional tests confirm the diagnosis and allow accurate counselling.

- Electro‑oculography (EOG) typically shows a markedly reduced light‑rise despite relatively preserved electroretinography (ERG).
- Genetic testing can identify pathogenic variants in the BEST1 gene or related genes.
- Results help distinguish Best disease from other inherited macular dystrophies and inform prognosis.
- Family screening may detect asymptomatic carriers and guide monitoring strategies.