DIAGNOSTIC CHALLENGES IN NECROTIC UVEAL MELANOMA

To describe a case of ciliochoroidal melanoma with massive spontaneous hemorrhagic retinal and choroidal detachment that presented a diagnostic challenge because of poor fundus visualization and atypical imaging features.

Case report.

A 71-year-old white man on apixaban for atrial fibrillation presented with sudden onset of pain and vision loss in the left eye. The patient was found to have total hemorrhagic retinal detachment and was referred for our opinion. On examination, visual acuity was 20/25 in the right eye and light perception in the left eye. Intraocular pressures were 10 mmHg in the right eye and 21 mmHg in the left eye. The unaffected right eye demonstrated only macular retinal pigment epithelial alterations. Evaluation of the left eye revealed dilated episcleral sentinel vessels superonasally, shallow anterior chamber, and total hemorrhagic retinal and choroidal detachment to the back of the crystalline lens. There was no view of the choroid. Transillumination demonstrated diffuse blockage of light from blood and no specific shadow. B-scan ultrasonography revealed total retinal and choroidal detachment with dense echoes of blood under the retina and in the suprachoroidal space with elevation of 12 mm and no definite mass or spontaneous vascular pulsations. Magnetic resonance imaging revealed diffuse high signals within the globe on T1-weighted images with no specific mass. On gadolinium enhancement, a localized enhancing area temporally of 12-mm thickness and a localized nonenhanced area nasally of 11-mm thickness was noted. Both areas showed low signal on T2-weighted images. Despite atypical features, suspicion for underlying ciliochoroidal melanoma and poor visual prognosis lead to enucleation. Histopathology confirmed an extensively necrotic, mushroom-shaped ciliochoroidal melanoma with total hemorrhagic retinal and choroidal detachment.

Diagnosis of necrotic posterior uveal melanoma can be challenging, because these tumors can be camouflaged by overlying hemorrhagic retinal and choroidal detachment and can present with atypical features on ultrasonography and magnetic resonance imaging. Patients with spontaneous hemorrhagic retinal and choroidal detachment should be evaluated for possible underlying malignancy.