68969: Comparative Study Of Neuropsychology、MRI and 18F‐FDG PET in Patients with Alzheimer’s Disease and Semantic Dementia

Abstract

AbstractBackgroundConfusion between Alzheimer’s disease (AD) and semantic dementia (SD) in early diagnosis is common, and most previous studies have been based on clinical diagnoses without a pathological diagnosis by biomarkers.Method15 patients 18F‐AV 45 PET (+) with AD and 9 patients 18F‐AV 45 PET (‐) with SD enrolled. All patients underwent the following examinations: (1) Neuropsychological tests, including Mini‐Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Activities of Daily Living (ADL), Boston Nomenclature Test (BNT), and Neuropsychiatric Scale table (NPI). (2) 3.0 head MRI examination, the imaging results were evaluated by MTA‐Scale, Koedam scale, and Kipps scale. (3) 18F‐FDG PET examination, PET images were quantitatively analyzed by Neuro Q software.ResultADL score increased in both groups, and the ADL score in the AD group was higher than that in the SD group (P = 0.035). BNT score decreased in both groups, but the BNT score in the SD group was lower than that in the AD group (P = 0.013). There were differences between the two groups in several psycho‐behavioral symptoms; delusions symptoms in the AD group were more prominent than those in the SD group (P = 0.009), and euphoria and disinhibition symptoms in the SD group were more pronounced than AD group (P = 0.015 and 0.015, respectively). The MRI atrophy rating scale showed that the left hippocampus, left frontal lobe, left anterior, and posterior temporal lobe atrophy in the SD group was more severe than that of the AD group (P = 0.018, 0.018, 0.022, and 0.044, respectively). Compared with the two groups of patients, the brain regions with significantly decreased metabolism in the AD group included the right inferior parietal lobule, right posterior cingulate gyrus, and left posterior cingulate gyrus (P = 0.037, 0.014, and 0.037, respectively); the brain regions with significantly decreased metabolism were left inferior frontal gyrus, left medial anterior temporal lobe, right medial anterior temporal lobe, left inferior lateral temporal lobe and left caudate nucleus (P = 0.017, 0.003, 0.037, 0.003, and 0.017, respectively).ConclusionNeuropsychology, brain structure, and brain metabolism aid in AD and SD differential diagnosis.