Echographic pseudoextension of uveal melanomas.

BACKGROUND

Standardized echography is routinely utilized to assess uveal melanomas. Echographic pseudoextension is defined as normal structures mimicking intrascleral or extrascleral extension of tumor on echography.

METHODS

The records of 151 consecutive uveal melanoma patients evaluated with standardized echography over a 6-year period (1986-1991) were reviewed to identify those in which pseudoextension or true extension was diagnosed.

RESULTS

Fourteen (9%) cases of pseudoextension were noted, with causes including juxtapapillary tumor location (seven cases), extraocular muscle insertion (five cases), vortex ampullae (one case), and post-brachytherapy changes (one case). Clinical, echographic, and/or histopathologic follow-up confirmed absence of true extension. Six (4%) cases of true extrascleral extension were identified and confirmed histopathologically.

CONCLUSION

Differentiating extraocular tumor extension from pseudoextension is critical, and use of standardized A-scan and contact B-scan echography is integral in this assessment.