Shielding in computed tomography: an update.

The primary purpose of this report is to review the general principles of shielding during computed tomography (CT) and to summarize the latest published information on shielding efficacy. Currently, there are discordant opinions within the literature regarding the appropriateness of shielding, particularly with regard to in-plane bismuth. Understanding that the decision to implement use of a particular type of shielding is not always the purview of the CT technologist, this update will outline the literature-supported best practices for each method and will attempt to clarify common misconceptions about proper use of shielding during CT procedures.