HMPAO SPECT imaging of Alzheimer's disease patients with similar content-specific autobiographic delusion: comparison using statistical parametric mapping.
Delusional behavior and thinking are common symptoms in Alzheimer's disease (AD). In the past, these delusions have been considered to be psychotic complications of global neurologic dysfunction. Recently, authors have suggested that content-specific delusions in AD are associated with discrete regional abnormalities of the right hemisphere.


METHODS
This study compared 99mTc-hexamethyl propyleneamine oxime (HMPAO) SPECT images of a group of AD patients with a similar autobiographic delusion with a group of AD patients without delusions and a group of AD patients with a range of delusions but without autobiographic content. The reconstructed SPECT data were compared using a statistical parametric mapping technique.


RESULTS
The autobiographic AD group had a significant area of hypoperfusion in the right frontal lobe when compared with the 2 other groups. The area of hypoperfusion included parts of Brodmann's areas 9 and 10. Region 9 has been identified previously as having a role in episodic memory retrieval.


CONCLUSIONS
This result suggests that autobiographic delusions in AD may have an identifiable neuropsychologic mechanism and that it may be possible to identify an organic cause in some patients using 99mTc-HMPAO SPECT.
Staff
R T
RT
Department of Bio-Medical Physics and Bio-Engineering, University of Aberdeen and Aberdeen Royal Infirmary, Foresterhill, Scotland, United Kingdom.
Venneri
A
A
Gemmell
H G
HG
Shanks
M F
MF
Pestell
S J
SJ
Murray
A D
AD
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging* / Q000523:psychology*; D000704:Analysis of Variance; D001921:Brain / Q000000981:diagnostic imaging*; D001931:Brain Mapping / Q000379:methods*; D003702:Delusions; D005260:Female; D006801:Humans; D008297:Male; D008609:Mental Status Schedule; D019275:Radiopharmaceuticals; D019690:Technetium Tc 99m Exametazime; D015899:Tomography, Emission-Computed, Single-Photon
D019275:Radiopharmaceuticals; D019690:Technetium Tc 99m Exametazime