Is there Still a Place for Perfusion SPECT in the Diagnosis of Dementia?

Abstract

Abstract:Although research interest within functional imaging has moved towards applications of MRI, such as BOLD and perfusion imaging, there is a wealth of clinical experience in emission tomographic imaging techniques that make the use of these modalities relevant for the decades to come. This review touches upon the technical and practical issues that distinguish SPECT from PET, describes perfusion and metabolic changes observed in the dementias, compares the clinical utility of the two techniques, and reports data on clinical sensitivity and specificity, as well as diagnostic head-to head comparisons in dementia, and specifically Alzheimer's disease. While few centres have a genuine choice between PET and SPECT, either appears to be good enough to help with the differential diagnosis of dementia in difficult cases.

Cerebral blood flow abnormality in clinically diagnosed Alzheimer's disease patients with or without amyloid β accumulation on positron emission tomography

“…AD starts with posterior cingulate or medial temporal hypoperfusion, followed by bilateral posterior temporoparietal hypoperfusion . Later, prefrontal hypoperfusion appears.…”

The Diagnostic Utility of ^99mTc-HMPAO SPECT Imaging: A Retrospective Case Series from a Tertiary Referral Early-Onset Cognitive Disorders Clinic

“…Two SPECT studies in patients with pathological diagnoses of AD reported sensitivities of 86 and 63%, and specificities of 73 and 93%, respectively [32,33]. Ebmeier [34 ]concluded that SPECT and PET are equally sensitive in aiding the differential diagnosis of dementia in challenging cases, with SPECT having the additional benefit of being the less costly than PET [35]. …”

A comparison of FDG‐PET and blood flow SPECT in the diagnosis of neurodegenerative dementias: a systematic review

“…Opinions still differ on whether PET or SPECT is more useful to aid diagnosis (Ishii and Minoshima, 2005;Lucignani and Nobili, 2010;Pupi and Nobili, 2005). Some reviews have also found in favour of PET (Devous, 2002;Silverman, 2004), with others finding both PET and SPECT to be useful to help differentiate dementia diagnoses (Ebmeier, 2010).…”

“…Studies of SPECT and PET in those with MCI have increasingly been carried out to examine whether such imaging techniques can predict the progression to dementia. These can be difficult to design and interpret Bloudek ( with MCI being a heterogeneous group with variable progression; also, the gold standard autopsy confirmed that studies are difficult because of the often long period between diagnosis and death (Ebmeier, 2010). The only head-to-head study carried out has already been mentioned (Dobert et al, 2005).…”

“…Over the last 30 years, there have been numerous publications reviewing the use of perfusion SPECT or FDG-PET in dementia, and each different technique has been the subject of previous reviews (Herholz et al, 2007;Pimlott and Ebmeier, 2007;Ebmeier, 2010;Berti et al, 2011). The majority of these have been in the form of studies concentrating on either SPECT or PET alone in the diagnosis or differentiation of dementia.…”