[Computed tomography and magnetic resonance imaging of choroidal melanoma].

Ten choroidal melanomas studied were with computed tomography (CT, nine cases) and magnetic resonance imaging (MRI, one case). Both techniques detected all the intraocular tumors with localization and determination of the extent of the lesions. Three of them were found to have extraocular extension. Because both T1 and T2 were relatively shortened in melanoma, on T-weighted MR image, the tumor was seen as an area of moderately high signal and on T weighted image, melanoma appeared as an area of low signal. MRI can provide a histological diagnosis of this tumor.