Densitometric analysis of scans: important sources of artefact

Abstract

Synopsis Computed tomography (CT) research in psychiatry often relies on the assessment of minor structural changes. Recently, it has come to encompass changes in regional brain X-ray absorption density. The artefacts prone to be encountered in density measurements are reviewed, and illustrated by a series of studies carried out using a CT 1010 scanner. They are shown to be more important than hitherto assumed in the interpretation of CT scan research.