Single photon emission computed tomography in Alzheimer's disease. Abnormal iofetamine I 123 uptake reflects dementia severity
K. A. Johnson, B. L. Holman, S. P. Mueller, T. J. Rosen, R. English, J. S. Nagel and J. H. Growdon
Department of Neurology, Massachusetts General Hospital, Boston 02114.
To determine whether abnormalities in regional cerebral functional activity
estimated by iofetamine hydrochloride I 123 and single photon emission
computed tomography can be detected in mild or moderate as well as severe
cases of Alzheimer's disease (AD), we performed iofetamine I 123-single
photon emission computed tomography in 37 patients with probable AD (nine
patients with mild, 18 patients with moderate, and ten patients with severe
dementia) and nine age-matched control subjects. Iofetamine I 123 uptake
was measured in right and left frontal, temporal, parietal, and occipital
cortices. Mean (right and left) iofetamine I 123 activity was lowest in the
parietal region of patients with AD and was significantly reduced in the
other three regions compared with control subjects. Only in the parietal
region was lower relative iofetamine I 123 activity associated with an
impaired level of patient function and with cognitive deficit.