A Metabolic Imaging Severity Rating Scale for the Assessment of Cognitive Impairment

摘要

Purposecolon;This study was designed to validate a simple scoring system for evaluating fluorodeoxyglucose lpar;FDGrpar; positron emission tomographic lpar;PETrpar; scans that can be used routinely in patients undergoing the clinical assessment of cognitive impairment.Methodscolon;The FDGhyphen;PET scans of 106 patients with cognitive impairment lpar;65 with Alzheimer disease, 16 with frontal lobe dementia, and 25 atypical casesrpar; were acquired using the PENNhyphen;PET scanner 40 minutes after the intravenous administration of 8 mCi FDG. Metabolic activity in various anatomic structures of the brain was scored using the following qualitative scalecolon; 4 equals; normalsemi; 3 equals; mildly decreasedsemi; 2 equals; moderately decreasedsemi; 1 equals; severely decreasedsemi; and 0 equals; no activity. Regions of interest were also placed over these regions to obtain a quantitative value. Two distinct scores were obtained. Values for visual and sensorimotor cortices, thalami, basal ganglia, and cerebellum comprised score I. Score II consisted of the values for the frontal, temporal, and parietal cortices. The qualitative metabolic imaging severity rating scale lpar;MISRSrpar; was compared with a quantitative MISRS lpar;obtained from the regionhyphen;ofhyphen;interest analysis of the same structuresrpar;. The MISRS was then compared with the results from the Minihyphen;Mental Status Examination lpar;MMSErpar; and the Dementia Severity Rating Score lpar;DSRSrpar;.Resultscolon;In all patients, the qualitative MISRS scores correlated significantly with the quantitative MISRS lpar;r equals; 0.73,P 0.0001rpar;. In all patients with cognitive impairment, the qualitative and quantitative MISRS scores correlated significantly with the DSRS and the MMSE lpar;P 0.001rpar;. In patients with Alzheimer disease, the qualitative and quantitative MISRS significantly correlated with the DSRS and MMSE.Conclusioncolon;A simple and practical rating scale can be used to assess the severity of cognitive impairment in patients with different types of dementing illnesses.