Task-Driven CT: Paper by Grace Gang in Phys Med Biol.

A paper published this month in the journal of Physics in Medicine and Biology reports a method that “takes imaging physics to task” to improve CT image quality and reduce dose. Grace Gang and coauthors Jeff Siewerdsen and Web Stayman combined methods for statistical 3D image reconstruction with mathematical models for task-based image quality to drive both the CT image acquisition and reconstruction process in a manner that is optimal to the imaging task. Among the findings is a new approach to tube current modulation that distributes x-ray fluence in a way that is completely different from conventional methods, maximizing imaging performance by reducing tube current in highly attenuating lateral views and instead spending radiation dose in less attenuating views where it has greater benefit to image quality. The result shows how model-based statistical 3D image reconstruction can completely change one’s approach to maximizing image quality. The work also shows how a joint optimization of acquisition technique and image reconstruction parameters is important in reducing radiation dose. The article can be found here and was supported by Dr. Stayman’s U01 grant on low-dose CT imaging.