IS THERE A ROLE FOR MRI IN DIAGNOSING UVEAL MELANOMAS?
Teresa P. Morais
BACKGROUND AND PURPOSE:
Uveal melanoma (UM) is the most common primary intraocular malignant neoplasms in adults. UM include choroid (85%), iris and ciliary body tumors, and the diagnosis depends on its location. UM have been diagnosed based on clinical history, ultrasound (US), fundoscopy, and fluorescein angiogram. Magnetic Resonance Imaging (MRI) has been used for extra-scleral extension and tumor size evaluation, both determinant findings for treatment planning, rather than to establish the diagnosis.
Our aim was to evaluate the potential role of MRI in the diagnosis of UM.
We performed a retrospective review of suspected UM clinical cases, who performed both B-mode US and MRI studies, in the diagnostic setting. The results of both modalities were compared with respect to lesion dimensions, extra-scleral extension and presence of retinal detachment (RD).
We found 6 patients, with suspected diagnosis of UM who underwent both B-mode US and MRI.
MRI excluded the diagnosis in one patient with suspected US imaging.
In the remaining 5 patients no significant differences were found regarding tumor size. Extra-scleral extension was not identified in all patients (n=6) by both techniques. RD was identified in two patients by US while MRI failed to identify a discrete RD in one of these subjects.
Despite the small sample size, MRI was able to exclude one US suspected case of UM, avoiding unnecessary debilitating treatment, while no significant differences were found regarding lesion size. Based on our findings, orbital MRI performed with a head coil may be useful in patients with suspected UM.