IN THE past few years attempts have been made to detect intracranial neoplasms with radioactive isotopes.* One of these was diiodofluorescein.2 This isotope has been shown to be of value in the detection of brain tumors. Since the retina and associated structures are closely allied to the brain, the possibility of detecting intraocular neoplasms by this technique was investigated.
The initial results obtained in the first three patients were unsatisfactory. It was felt that diiodofluorescein failed because it emitted gamma rays. Such rays mask detection of any concentration in a tumor of the eye, for the following reasons:
1. The volume of an intraocular neoplasm rarely occupies more than one-fourth of the globe.
2. Diiodofluorescein is taken up by normal tissue, as well as by pathologic tissue.
3. Gamma rays have marked penetrating power in tissue.
It appeared that a substance emitting pure beta rays would be preferable, as
EISENBERG IJ, LEOPOLD IH, SKLAROFF D. USE OF RADIOACTIVE PHOSPHORUS IN DETECTION OF INTRAOCULAR NEOPLASMS. AMA Arch Ophthalmol. 1954;51(5):633-641. doi:10.1001/archopht.1954.00920040643007