UVEAL MELANOMA - DETECTION OF EXTRAOCULAR GROWTH WITH MR-IMAGING AND US

PURPOSE: To compare the sensitivity and specificity of magnetic resona nce (MR) imaging with that of ultrasound (US) in the detection of extr aocular extension of uveal melanoma. MATERIALS AND METHODS: In 70 pati ents the diagnosis of melanoma and absence or presence of extraocular growth were confirmed with histologic examination (13 patients) or wit h ophthalmoscopy and surgery (57 patients). Unenhanced and enhanced T1 -weighted and T2-weighted MR imaging was performed with surface coils at 1.5 T. A- and B-mode US scans were obtained with 8- and 10-MHz prob es,respectively. RESULTS: Extraocular growth was confirmed in seven pa tients: Five patients had retrobulbar tumor, and two had optic nerve i nfiltration. US enabled detection in three cases, whereas six cases we re diagnosed with MR imaging including both cases of optic nerve infil tration. False-positive findings were more frequent with US (n = 5) th an with MR imaging (n = 1). CONCLUSION: MR imaging proved to be more s ensitive and more specific than US in the detection of extraocular ext ension of uveal melanoma.