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Multivariate spatial covariance analysis of 99mTc-exametazime SPECT images in dementia with Lewy bodies and Alzheimer’s disease: utility in differential diagnosis


Colloby, Sean J, Taylor, John-Paul, Davison, Christopher M, Lloyd, Jim J, Firbank, Michael J, McKeith, Ian G, O'Brien, John T


Journal Of Cerebral Blood Flow And Metabolism: Official Journal Of The International Society Of Cerebral Blood Flow And Metabolism, Volume: 33, No.: 4, Pages.: 612-618

Year of Publication



We examined (99m)Tc-exametazime brain blood flow single-photon emission computed tomography (SPECT) images using a spatial covariance analysis (SCA) approach to assess its diagnostic value in distinguishing dementia with Lewy bodies (DLB) from Alzheimer’s disease (AD). Voxel SCA was simultaneously applied to a set of preprocessed images (AD, n=40; DLB, n=26), generating a series of eigenimages representing common intercorrelated voxels in AD and DLB. Linear regression derived a spatial covariance pattern (SCP) that discriminated DLB from AD. To investigate the diagnostic value of the model SCP, the SCP was validated by applying it to a second, independent, AD and DLB cohort (AD, n=34; DLB, n=29). Mean SCP expressions differed between AD and DLB (F(1,64)=36.2, P<0.001) with good diagnostic accuracy (receiver operating characteristic (ROC) curve area 0.87, sensitivity 81%, specificity 88%). Forward application of the model SCP to the independent cohort revealed similar differences between groups (F(1,61)=38.4, P<0.001), also with good diagnostic accuracy (ROC 0.86, sensitivity 80%, specificity 80%). Multivariate analysis of blood flow SPECT data appears to be robust and shows good diagnostic accuracy in two independent cohorts for distinguishing DLB from AD.;

Bibtex Citation

@article{Colloby_2013, doi = {10.1038/jcbfm.2013.2}, url = {}, year = 2013, month = {jan}, publisher = {{SAGE} Publications}, volume = {33}, number = {4}, pages = {612--618}, author = {Sean J Colloby and John-Paul Taylor and Christopher M Davison and Jim J Lloyd and Michael J Firbank and Ian G McKeith and John T O{textquotesingle}Brien}, title = {Multivariate spatial covariance analysis of 99mTc-exametazime {SPECT} images in dementia with Lewy bodies and Alzheimer's disease: utility in differential diagnosis}, journal = {Journal of Cerebral Blood Flow {&} Metabolism} }


accuracy, administration & dosage, alzheimer disease, butanones, cohort studies, diagnosis, differential, diagnostic, female, humans, lewy bodies, lewy body disease, male, organotechnetium compounds, radiography

Countries of Study


Types of Dementia

Alzheimer’s Disease, Lewy-Body

Types of Study

Cohort Study

Type of Outcomes


Type of Interventions

Diagnostic Target Identification

Diagnostic Targets

Neuroimaging (e.g. MRI, PET, CAT etc.)