Positron Emission Tomography in Evaluation of Dementia: Regional Brain Metabolism and Long-term Outcome
2001
ContextDeficits in cerebral glucose utilization have been identified in patients
with cognitive dysfunction attributed to various disease processes, but their
prognostic and diagnostic value remains to be defined.ObjectiveTo assess the sensitivity and specificity with which cerebral metabolic
patterns at a single point in time forecast subsequent documentation of progressive
dementia.Design, Setting, and PatientsPositron emission tomography (PET) studies of [18F]fluorodeoxyglucose
in 146 patients undergoing evaluation for dementia with at least 2 years'
follow-up for disease progression at the University of California, Los Angeles,
from 1991 to 2000, and PET studies in 138 patients undergoing evaluation for
dementia at an international consortium of facilities, with histopathological
diagnoses an average of 2.9 years later, conducted from 1984 to 2000.Main Outcome MeasuresRegional distribution of [18F]fluorodeoxyglucose in each
patient, classified by criteria established a priori as positive or negative
for presence of a progressive neurodegenerative disease in general and of
Alzheimer disease (AD) specifically, compared with results of longitudinal
or neuropathologic analyses.ResultsProgressive dementia was detected by PET with a sensitivity of 93% (191/206)
and a specificity of 76% (59/78). Among patients with neuropathologically
based diagnoses, PET identified patients with AD and patients with any neurodegenerative
disease with a sensitivity of 94% and specificities of 73% and 78%, respectively.
The negative likelihood ratio of experiencing a progressive vs nonprogressive
course over the several years following a single negative brain PET scan was
0.10 (95% confidence interval, 0.06-0.16), and the initial pattern of cerebral
metabolism was significantly associated with the subsequent course of progression
overall (P<.001).ConclusionIn patients presenting with cognitive symptoms of dementia, regional
brain metabolism was a sensitive indicator of AD and of neurodegenerative
disease in general. A negative PET scan indicated that pathologic progression
of cognitive impairment during the mean 3-year follow-up was unlikely to occur.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
24
References
779
Citations
NaN
KQI