Medical Care
No treatment exists for vitelliform macular dystrophy (Best disease). Secondary choroidal neovascularization (CNVM) can be managed with direct laser treatment or photodynamic therapy [32, 33] ; however, treatment with anti–vascular endothelial growth factor (VEGF) therapy, including intravitreal injection of bevacizumab, has been reported more recently. [34, 5] CNVMs may spontaneously resolve without treatment, but vision outcomes are better with anti-VEGF than with observation alone. [34]
Evaluation of family members is important to identify carriers and individuals with vitelliform macular dystrophy. Both genetic counseling and career counseling are provided.
Future directions for research may include gene therapy targeting BEST1. [35]
Consultations
Consult a vitreoretinal disease specialist for the initial diagnosis, electrophysiology testing, and family assessment, as well as for the long-term follow-up care of patients to monitor disease progression and choroidal neovascularization.
Consult a low vision specialist who can provide specialized equipment to assist individuals who have significant deterioration in visual acuity in both eyes.
Occupational counseling is important. Although most patients retain reading vision in at least 1 eye throughout life, visual deterioration can occur, particularly beyond age 40 years. This knowledge may influence the choice of career.
Diet
Diet is not known to influence the progression of Best disease.
Activity
Physical activity does not influence the progression of Best disease.
Long-Term Monitoring
Examination of visual acuity and fundus lesions should be performed on a schedule dictated by the current stage of the disease. If visual changes occur at any stage, then an earlier visit should be scheduled, as follows:
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Previtelliform stage - Yearly
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Vitelliform/pseudohypopyon stage - Every 6 months
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Scrambled egg stage - Every 6 months
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Atrophic stage - Every 6 months to yearly
Patients in the atrophic stage should routinely use an Amsler grid. Changes in the central visual field should prompt an early visit to evaluate for choroidal neovascularization.
The electrophysiology test is usually only necessary once to establish the diagnosis. Initial results remain fairly stable during disease progression.
Fluorescein angiography should be performed at any visit if choroidal neovascularization is suspected.
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Classic egg-yolk appearance in the second (vitelliform) stage of vitelliform macular dystrophy. The 0.5-6 mm diameter yellow or orange lesion results from an accumulation of lipofuscin beneath and within the retinal pigment epithelium. This lesion is usually noted in individuals aged 3-15 years. Visual acuity is most often preserved in the 20/20 to 20/40 range.
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The pseudohypopyon (stage 3) lesion is found in the teenage or later years. It results from a break in the retinal pigment epithelium, allowing accumulation of the yellow substance in the subretinal space with the formation of a fluid level. This fluid can shift over 60-90 minutes with positioning.
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The atrophic stage (stage 5) may be accompanied by the deposition of pigment or choroidal neovascularization, both of which can lead to visual deterioration.
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The scrambled egg appearance of stage 4 results from a deterioration of the uniform cystic lesion noted in stage 2 (egg-yolk appearance). At this point, the visual acuity can begin to worsen.
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Adult vitelliform macular dystrophy resembles Best disease, but it can be differentiated by its later age of onset, smaller lesion, and normal electro-oculogram testing.
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The fluorescein angiogram of the latter lesion reveals a transmission defect consistent with atrophic changes in the retinal pigment epithelium. This appearance also can be found in the later stages of Best disease.
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Spectral domain optical coherence tomography demonstrates subretinal lesion with adjacent cystoid macular edema.
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Autosomal-recessive bestrophinopathy: Atrophic central lesion and white subretinal deposits along the vascular arcades in a 14-year-old female with 20/70 vision and no family history of Best macular dystrophy.