Cerebral perfusion imaging with iodine 123-labeled amines.

Two amines, N-isopropyl p-iodoamphetamine and N,N,N'-trimethyl-N'-[2-hydroxyl-3-methyl-5-iodobenzyl]-1,3-prop anediamine, have been labeled with iodine 123. The brain uptake of these radioactive tracers is proportional to cerebral blood flow. These tracers are retained in the brain for a sufficiently long time so that imaging can be performed with standard, readily available instrumentation. Transaxial tomography with amines is useful in acute cerebral infarction, in which the x-ray computed tomographic scan may be normal for several days after onset of symptoms while the uptake of radioisotope-labeled amines will be altered immediately after the onset of the stroke. It is also useful in examining patients with cerebral vascular disease and in the preoperative examination of patients with partial epilepsy.