Abstract

Radiation dosimetry in CT: the role of the manufacturer

Author(s): Walter Huda

This article provides an overview of CT dose indices (CTDIs) currently used to quantify the amount of radiation used to perform clinical CT examinations. The manner in which CTDI metrics can be used to estimate the amount of radiation received by any given patient undergoing a CT examination is explained. The role of the manufacturer in providing information on the amount of radiation used to perform CT scans, as well as the corresponding patient doses, is addressed. Manufacturers have specific obligations to provide data on the quantity and quality of the x-ray radiation that is incident on patients, and should also be required to indicate whether this amount is reasonable, taking into account patient characteristics (i.e., size) and the imaging task. Manufacturers could also develop software that would provide conversion factors to enable operators to translate CT output into patient doses. Technological advances in CT scanners, and specifically cone beam CT which use wide x-ray beams, will require modification or replacement of current CTDI metrics. Alternatives to current CTDI metrics are described, and manufacturers need to assess their suitability for specifying the amount of radiation emitted by CT scanners in clinical examinations.