CT brain perfusion: A static phantom study of contrast-to-noise ratio and radiation dose

Abstract

Introduction: Computed tomography perfusion (CTP) is increasingly employed in the diagnosis and management of ischaemic stroke but radiation dose can be significant and optimising contrast-to-noise ratio (CNR) is challenging. This study aimed to quantify and optimise the balance between CNR as a surrogate for image quality and radiation dose. Methods: A perspex head phantom with vials of dilute contrast agent was scanned using a Siemens Definition Flash 128-slice scanner. The CTP protocol exposure parameters were adjusted over 70–120 kVp and 150–285 mAs. Measurements were obtained for the average dose per slice, Hounsfield Units (HU) for iodinated contrast agent, and the image noise for back..