THE EMERGENCE of scintillation scanning of the brain for localization of brain tumors has been a major advance in neurological diagnosis. Moore,1 in 1948, was able to localize brain tumors by the use of radioactive iodine-labeled diiodofluorescein and a Geiger-Meuller tube. Since this time there have been major technological advances with the development of sensitive scintillation counters, automatic scanning equipment, and focusing collimators.2
The most commonly employed agent for brain tumor localization has been iodinated I 131 serum albumin,3 although other compounds have been employed. In 1959, Chlormerodrin Hg-203 was introduced as an agent for brain tumor localization by Blau and Bender,4 and numerous reports since have attested to its value in brain tumor localization.5-8 The mechanism of localization of brain tumors by scintillation scanning has received some attention in the literature but further information is needed to understand more fully the manner in