ECHOGRAPHIC PSEUDOEXTENSION OF UVEAL MELANOMAS

Background: Standardized echography is routinely utilized to assess uv eal melanomas. Echographic pseudoextension is defined as normal struct ures mimicking intrascleral or extrascleral extension of tumor on echo graphy. Methods: The records of 151 consecutive uveal melanoma patient s evaluated with standardized echography over a 6-year period (1986-19 91) were reviewed to identify those in which pseudoextension or true e xtension was diagnosed. Results: Fourteen (9%) cases of pseudoextensio n were noted, with causes including juxtapapillary tumor location (sev en cases), extraocular muscle insertion (five cases), vortex ampullae (one case), and post-brachytherapy changes (one case). Clinical, echog raphic, and/or histopathologic follow-up confirmed absence of true ext ension. Six (4%) cases of true extrascleral extension were identified and confirmed histopathologically. Conclusion: Differentiating extraoc ular tumor extension from pseudoextension is critical, and use of stan dardized A-scan and contact B-scan echography is integral in this asse ssment.