Cerebral perfusion changes in older delirious patients using 99mTc HMPAO SPECT.
BACKGROUND
Prior studies describe variable cerebral blood flow changes in delirium. This study aims to investigate cerebral blood flow changes in older hospitalized patients with delirium, the population in which most cases of delirium occur.


METHODS
Participants included hospitalized general medical patients aged 65 years and older with documented delirium and no relevant medical conditions or preexisting abnormalities on neuroimaging prospectively studied using 99mTc HMPAO single photon emission computed tomography (SPECT) scans obtained during and after resolution of delirium. Twenty-two patients enrolled in the study, of whom six completed both scans. All participants underwent neuropsychological assessment immediately prior to SPECT scanning. SPECT images were compared across all participants during delirium; for patients completing paired scans, within-patient comparisons were made.


RESULTS
Visual assessment of SPECT scans revealed perfusion abnormalities in frontal (5 participants) or parietal regions (6 participants); scans were normal in 11 participants (50%). Region-of-interest analysis identified reduced blood flow (p <.01) in the left inferior frontal, right temporal, right occipital, and pontine regions. Analysis of paired scans revealed reversible abnormalities in three participants (p <.001), with decreased right parietal perfusion in two participants and increased left parietal perfusion in one participant.


CONCLUSIONS
The results of this study of a small group of general medical patients are suggestive that frontal or parietal cerebral perfusion abnormalities occur in delirium, and these findings need to be confirmed by future, larger studies. These results may help to improve basic understanding of delirium pathophysiology, to identify long-term changes, and to evaluate response to treatment over time.
Fong
Tamara G
TG
Department of Neurlogy, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA. tfong@bidmc.harvard.edu
Bogardus
Sidney T
ST
Daftary
Aditya
A
Auerbach
Eliza
E
Blumenfeld
Hal
H
Modur
Sharada
S
Leo-Summers
Linda
L
Seibyl
John
J
Inouye
Sharon K
SK
D000368:Aged; D000369:Aged, 80 and over; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003693:Delirium / Q000503:physiopathology* / Q000523:psychology; D005260:Female; D005625:Frontal Lobe / Q000098:blood supply; D006801:Humans; D008297:Male; D010296:Parietal Lobe / Q000098:blood supply; D019275:Radiopharmaceuticals; D012039:Regional Blood Flow / Q000502:physiology; D019690:Technetium Tc 99m Exametazime; D015899:Tomography, Emission-Computed, Single-Photon
D019275:Radiopharmaceuticals; D019690:Technetium Tc 99m Exametazime