BACKGROUND: Isolated choroidal melanocytosis refers to patchy melanocytic choroidal hyperpigmentation without the associated scleral or cutaneous pigmentation seen in ocular melanocytosis or oculodermal melanocytosis. Neither bilateral nor diffuse cases, to our knowledge, have been previously described in the literature. METHODS: Case report. PATIENT: A 43-year-old woman without cutaneous or scleral hyperpigmentation or vitiligo was noted to have diffuse patchy melanocytic choroidal hyperpigmentation with feathered margins for nearly 12 clock hours in both eyes. Large choroidal vascular sparing was noted in several areas. RESULTS: B-scan ultrasonography demonstrated a normal choroidal thickness. Cutaneous biopsy with Fontana Masson stain for melanin was within normal limits, without giant melanosomes. CONCLUSIONS: Isolated choroidal melanocytosis may present bilaterally and diffusely.
