Choroidal Nevus; Clinical Findings, Imaging Findings and Diagnosis

Abstract

Choroidal nevus is a benign melanocytic tumor that is often incidentally detected during ophthalmic examinations. It is typically located behind the equator of the eye and appears as a flat or slightly elevated lesion with indistinct borders. The shape of the nevus can be round or oval, and its color varies from brown to dark gray, depending on the amount of pigment present. Most nevi are asymptomatic. However, if choroidal neovascularization or serous retinal detachment develops, it can lead to a decrease in vision and become symptomatic. Fundus photography, B-mode ultrasonography, and optical coherence tomography are useful imaging techniques for clinical monitoring. Differential diagnosis between choroidal nevus and melanoma is important. Risk factors for the development of melanoma include a thickness greater than 2 mm, a basal diameter larger than 6 mm, the presence of lipofuscin pigment accumulation on the surface, proximity to the optic disc within 3 mm, serous retinal detachment, and visual impairment. These factors require further investigation.