Radioactive phosphorus uptake studies have proved useful in the differential diagnosis of mass lesions of the posterior uveal tract. The authors describe a modification in technique, stressing precise localization of the lesion by indirect ophthalmoscopy and accurate positioning of the counting probe directly over the lesion. There were 41 posterior choroidal lesions studied with no false positive results and only two false negative tests. Hemangiomas, choroidal hematomas, and benign retinal vascular tumors can be distinguished from malignant lesions by means of this test. The radioactive phosphorus uptake test was not found to be helpful in iris tumors.
Hagler WS, Jarrett WH, Humphrey WT. The Radioactive Phosphorus Uptake Test in Diagnosis of Uveal Melanoma. Arch Ophthalmol. 1970;83(5):548-557. doi:10.1001/archopht.1970.00990030548005