Iterative Reconstruction Technique (IRT) is a new CT reconstruction algorithm, and there have been many reports on the use of it to improve image quality and dose reduction in CT. The temporal bone has fine anatomic structures that demand higher spatial resolution than most other clinical targets. We chose this topic because, to our knowledge, no study to date had investigated the ability of IRT to reduce radiation dose to the temporal bone.

Our study showed that the use of IRT can help reduce radiation dose from temporal bone by 50% relative to routine institution protocols with filtered back-projection, while maintaining diagnostic image quality. The new protocol is very useful for the protection of patients, particularly children. But there are also some radiologists who told us that the noise and artifact characteristics of IRT are different from those of filtered back-projection. This suggests that radiologists will need time and experience to adapt to the appearance of images reconstructed with IRT.

Our experimental methods described herein may be used as a means to select optimal scanning parameters and level of iterative algorithm for different regions of anatomy, and even for different CT manufacturers.

Read this article at AJNR.org . . .