XE-133 SPECT-DETERMINED REGIONAL CEREBRAL BLOOD-FLOW IN ALZHEIMERS-DISEASE - WHAT IS TYPICAL

A study of 76 consecutive xenon-133 SPECT studies of regional cerebral blood flow was undertaken to determine the frequency of various patte rns of blood flow in cases of clinically diagnosed probable and possib le Alzheimer's disease. The reference tomographic section was a slice 6 cm above and parallel to the canthomeatal line. With the use of this technique, the ''classic'' finding of bilateral temporoparietal (TP) flow reductions as the sole abnormality occurred in only 28% of cases. Bilateral TP reductions accompanied by bilateral or unilateral fronta l flow reductions were nearly as common (24%), and other patterns acco unted for the other 48% of cases.