SPECT and Alzheimer's Disease

Abstract

Abstract: This article is review of the role of single photon emission tomography (SPECT) in the diagnosis and management of Alzheimer's disease (AD).It begins by describing AD in terms of diagnosis, pathology and current pharmacological treatment. The relevance of the pathological changes in relation to SPECT is outlined. This is discussed in terms of receptor abnormalities and atrophic changes which in turn effect cerebral blood flow.A detailed description of SPECT methodology describes how the quality of the image is effected by SPECT instrumentation, image reconstruction techniques and a number of subject factors.The article goes on to discuss the role SPECT in the diagnosis of AD and its potential for facilitating early diagnosis. The main focus here is on the changes which occur in cerebral blood flow in AD and the sensitivity and specificity of regional changes in cerebral blood flow is described.Image analysis is an area in which there has been many developments in the last number of years and the authors describe the differences between qualitative and quantitative image analysis, with a particular focus on statistical parametric mapping (SPM).There is a brief discussion concerning receptor ligands and their potential use in the diagnosis and management of AD, although this remains an undeveloped area in SPECT imaging as yet.Finally, the authors discuss the future possibilities for SPECT and AD, and conclude that there is considerable potential for SPECT in the diagnosis and management of AD with further refinement of image analysis techniques and the development of cholinergic receptor ligands.