Clinical imaging and high-resolution ultrasonography in melanocytoma management

PURPOSE To demonstrate the utility of high resolution 20 MHz ophthalmic ultrasound in serial follow-up of optic nerve head melanocytoma patients. METHODS This study is a retrospective review of 30 patients with melanocytoma of the optic nerve head studied with echography. All patients were evaluated with standard ophthalmic A-scan and B-scan ultrasonography and 10 (33%) underwent high-resolution ultrasound. RESULTS Sixty-two percent (62%) of patients had dome-shaped lesions on ultrasound, twenty-eight percent (28%) presented with mild elevations. The maximum elevation of any lesion was 2.6 mm. The vast majority (89%) of lesions had medium or high internal reflectivity and 89% demonstrated avascularity. Mean follow-up for all patients was nearly 7 years. High-resolution ultrasound enabled enhanced accuracy for detection of lesion dimensions and documentation of growth and possible malignant transformation. CONCLUSIONS In this study, we demonstrate a new and important role for the use of ultrasound in this disease as a complementary tool in identifying and following patients with high-risk growth characteristics. These tumor characteristics can be accurately detected with 10 MHz ultrasound in conjunction with standardized A-scan and better differentiated with the 20 MHz technology. Use of these modalities can aid in distinguishing the melanocytomas that grow from choroidal melanomas and can prevent unnecessary treatments.