European Journal of Nuclear Medicine Vol. 29, No. 5, May 2002 Abstract. Differences in regional cerebral blood flow (rCBF) between subjects with Alzheimer’s disease (AD), dementia with Lewy bodies (DLB) and healthy volun- teers were investigated using statistical parametric map- ping (SPM99). Forty-eight AD, 23 DLB and 20 age- matched control subjects participated. Technetium-99m hexamethylpropylene amine oxime (HMPAO) brain sin- gle-photon emission tomography (SPET) scans were ac- quired for each subject using a single-headed rotating gamma camera (IGE CamStar XR/T). The SPET images were spatially normalised and group comparison was performed by SPM99. In addition, covariate analysis was undertaken on the standardised images taking the Mini Mental State Examination (MMSE) scores as a variable. Applying a height threshold of P≤0.001 uncor- rected, significant perfusion deficits in the parietal and frontal regions of the brain were observed in both AD and DLB groups compared with the control subjects. In addition, significant temporoparietal perfusion deficits were identified in the AD subjects, whereas the DLB pa- tients had deficits in the occipital region. Comparison of dementia groups (height threshold of P≤0.01 uncorrect- ed) yielded hypoperfusion in both the parietal [Brod- mann area (BA) 7] and occipital (BA 17, 18) regions of the brain in DLB compared with AD. Abnormalities in these areas, which included visual cortex and several ar- eas involved in higher visual processing and visuospatial function, may be important in understanding the visual hallucinations and visuospatial deficits which are charac- teristic of DLB. Covariate analysis indicated group dif- ferences between AD and DLB in terms of a positive correlation between cognitive test score and temporopa- rietal blood flow. In conclusion, we found evidence of frontal and parietal hypoperfusion in both AD and DLB, while temporal perfusion deficits were observed exclu- sively in AD and parieto-occipital deficits in DLB. Keywords: Dementia with Lewy bodies – Alzheimer’s disease – Single-photon emission tomography – Statisti- cal parametric mapping Eur J Nucl Med (2002) 29:615–622 DOI 10.1007/s00259-002-0778-5 Introduction Cerebral blood flow imaging using single-photon emis- sion tomography (SPET) provides a sensitive diagnostic and research tool for the assessment of regional cerebral blood flow (rCBF) in Alzheimer’s disease (AD) [1] and, more recently, in dementia with Lewy bodies (DLB). The predominant rCBF pattern observed in patients with AD is one of bilateral parietotemporal abnormality [2, 3], and probably frontal defects [4, 5, 6]. SPET studies involving subjects with DLB have produced varied re- sults. Occipital hypoperfusion in DLB with respect to AD have been reported [7, 8], while others using visual rating methods have observed a reduction in perfusion in both the temporoparietal and the occipital region in DLB [9]. Glucose hypometabolism from positron emission to- mography (PET) studies was also reported in the occipi- tal area in DLB [10]. However Defebvre et al. observed a reduction in uptake exclusively in the frontal areas in DLB compared with AD [11]. One possible explanation for this variability may be in the small numbers of sub- John T. O’Brien ( ✉ ) Wolfson Research Centre, The Institute for Ageing and Health, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne, NE4 6BE, UK e-mail: j.t.o’brien@ncl.ac.uk Tel.: +44-191-2563323, Fax: +44-191-2195051 Original article A comparison of 99m Tc-HMPAO SPET changes in dementia with Lewy bodies and Alzheimer’s disease using statistical parametric mapping Sean J. Colloby 1 , John D. Fenwick 2 , E. David Williams 3 , Sean M. Paling 1 , Kyriakos Lobotesis 1 , Clive Ballard 1 , Ian McKeith 1 , John T. O’Brien 1 1 Wolfson Research Centre, The Institute for Ageing and Health, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne, NE4 6BE, UK 2 Regional Medical Physics Department, Newcastle General Hospital, Newcastle upon Tyne, UK 3 Regional Medical Physics Department, Sunderland Royal Hospital, Sunderland, UK Received 21 September 2001 and in revised form 16 January 2002 / Published online: 5 March 2002 © Springer-Verlag 2002