Jie Tang PhD, Presenter: Grant, General Electric Company

Jiang Hsieh PhD, Abstract Co-Author: Employee, General Electric Company

Guang-Hong Chen PhD, Abstract Co-Author: Nothing to Disclose

The recently proposed Prior Image Constrained Compressed Sensing (PICCS) has been applied in cardiac MDCT to improve the temporal resolution by approximately a factor of 2, by using projection data acquired from half of the standard short-scan angular range to reconstruct images with improved temporal resolution. The aim of this study is to determine if the performance of TRI-PICCS is dependent upon the orientation and motion pattern of moving objects.

A hybrid phantom consisting of realistic cardiac anatomy plus objects moving with known trajectories was constructed by adding analytical projection data of simulated moving vessels to the projection data from cardiac MDCT exams. A single vessel was simulated with 12 different orientations for a single acquisition, in order to study the dependence on the relationship between the relative orientation of the selected view angles and the motion direction. Additionally, the position dependence was studied by placing the simulated vessel at a variety of locations within the field of view. The gold standard for reconstructing this data is a short-scan FBP reconstruction. This image is used as the prior image for the TRI-PICCS algorithm. To improve the temporal resolution, the TRI-PICCS algorithm uses only a subset (e.g. the first half of the short scan data) of the data and the prior image for image reconstruction.

For all of the studies conducted here half of the projection data of a short scan was used yielding approximately a factor of two improvement in temporal resolution. In the motion direction studies, in any motion direction, the TRI-PICCS algorithm eliminates the motion artifacts in the FBP reconstructions. In the motion location studies, the TRI-PICCS algorithm also generates images with high temporal resolution, and fewer motion artifacts than the gold standard FBP reconstruction.

The results of simulation studies with realistic background anatomy indicate that approximately a factor of 2 improvement in the temporal resolution using TRI-PICCS is independent of the motion direction and the location of the moving objects.

The temporal resolution of MDCT can be improved by approximately a factor of 2 by using the TRI-PICCS algorithm without modifying any scanner hardware or changing acquisition protocols.

Tang, J, Hsieh, J, Chen, G, Temporal Resolution Improvement Prior Image Constrained Compressed Sensing (TRI-PICCS): Performance as a Function the Orientation and Motion Pattern of Moving Objects.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8016614.html