Cerebrospinal fluid scanning with 111 In.

Abstract

Summary Indium-111 is now available for radionuclide procedures in humans. This cyclotron-produced radionuclide decays by electron capture with a half-life of 2.8 days. There is no beta emission, and 1.8 gamma rays useful for scanning are emitted per disintegration. Radiopharmaceuticals using this nuclide have been developed for cerebrospinal fluid scanning because of the almost ideal half-life and decay scheme. An indium-transferrin complex, using the patient9s own serum, has been used in animals and in one human. This benign radiopharmaceutical has been shown to follow the natural CSF pathways delineated by 131I-iodinated human serum albumin (IHSA) and therefore appears to be useful for routine CSF scanning. Colloids such as indium phosphate colloid collect at the region of the basal cisterns and are unsatisfactory for cisternography. The use of 111In in chelates such as EDTA and DTPA will be evaluated in future studies. If 111In can be successfully bound to albumin, its use as a CSF scanning agent will be explored.