Brain Scanning with Mercury203 Labeled Neohydrin

Abstract

Photoscanning with Hg203 was shown to be a useful diagnostic method for localization of intracranial tumors. It is an outpatient procedure carrying no immediate risk but the dosimetry, particularly in children, does not justify its indiscriminate use as a screening procedure. A blocking dose of a mercurial diuretic should be given intramuscularly to minimize effects of radiation to the kidneys. Every patient with a positive scan showed an expanding lesion. Scanning can be carried out by one easily trained technician at a cost comparable to percutaneous arteriography. Malignant gliomas almost invariably are localized by scanning. Meningiomas were localized in over 80% of the cases; the 2 that failed to localize were characterized by their relative avascularity. In patients with intracranial metastases, scans were positive in 70%. When there was a differential isotope uptake in tumors, abscesses, and subdural hematomas, new blood-vessel formation was demonstrated in each. (H.H.D.)