Affiliations: [a] Department of Nuclear Medicine and Centre for PET, Austin Health, The University of Melbourne, VIC, Australia | [b] Department of Aged Care, Austin Health, Melbourne, VIC, Australia
Correspondence:
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Correspondence to: Christopher Rowe, Director of Nuclear Medicine, Austin Hospital, The University of Melbourne, 145 Studley Road PO Box 5555 Heidelberg, VIC 3084, Australia. Tel.: +61 3 9496 5183; Fax: +61 3 9496 5663; E-mail: christopher.rowe@austin.org.au.
Abstract: Background:2-[18F]fluoro-2-Deoxy-D-glucose (FDG) positron emission tomography (PET) may assist the diagnosis of dementia but it is an expensive investigation. Objective:To obtain management impact data for FDG-PET in dementia. Methods:This was a prospective study of 194 consecutive patients referred from a memory clinic for FDG-PET at the discretion of the dementia specialists. Diagnosis and management plans formulated at a multidisciplinary patient review meeting were compared before and after the release of PET findings. Results:FDG-PET had moderate to high impact on the diagnosis and management in 85 (44%) participants. Diagnosis changed from probable neurodegenerative disease in 27 patients to a non-degenerative diagnosis and vice versa in 12 patients. PET changed the type of dementia in another 29 (15%) participants and prescription of cholinesterase inhibitors in 33 patients (17%).Number of uncertain diagnoses reduced from 58 to 35 (p < 0.001, χ2 = 15.12), differential diagnoses reduced from 127 to 55 (p = 0.003) and very probable diagnoses increased from 5 to 42 (p ≤ 0.001, χ2 = 1.01). Mini-Mental State Examination score was higher in those where PET had high diagnostic impact (26.3 ± 3.1 versus 23.9 ± 5.1, p ≤ 0.05). The degree of impact correlated with the pre-scan level of diagnostic uncertainty (ρ = −0.258, p < 0.001). Discussion:The management impact was higher in those with greater diagnostic uncertainty and in those with less severe cognitive impairment. The findings suggest that FDG-PET is a useful adjunct for the management of suspected dementing disorders in appropriately selected patients.
