Studies in diagnosis of choroidal melanoma: use of 67Gallium.

A series of clinically suspected malignant melanomas was used to test the usefulness of 67Gallium citrate using external counting techniques. The comparison was made with angiograms, 32P uptake, and clinical examinations. 67Gallium citrate uptkae proved to be an unreliable diagnostic tool with the described techniques. However, sufficient tissue concentration was obtained tin the tumor to suggest that improved probe counting systems with better resolution of ocular from extraocular tissue may allow this to become a useful technique in differentiating tumor from nontumor ocular pathology. A good indirect and direct ophthalmoscopic examination, along with periodic observation, were the most useful techniques for diagnosis in these cases. 32P uptake was extremely reliable (100%) and quite helpful in assuring the proper diagnosis.