James H Holmes PhD, Presenter: Employee, General Electric Company

Howard A. Rowley MD, Abstract Co-Author: Research Consultant, Eli Lilly and Company Research Consultant, W.L. Gore & Associates, Inc Research Consultant, Medpace, Inc Research Consultant, H. Lundbeck A/S Research Consultant, Bayer AG Research Consultant, General Electric Company Speaker, Bracco Group Researcher, Guerbet SA

Philip Beatty, Abstract Co-Author: Employee, General Electric Company

Jean Helen Brittain PhD, Abstract Co-Author: Employee, General Electric Company

The purpose of this work is to evaluate the image quality of a new PROPELLER pulse sequence for imaging moving subjects while maintaining high T1 FLAIR contrast in neuro MRI.

MRI images were reconstructed using a new PROPELLER acquisition combined with externally calibrated parallel imaging. This enabled significantly wider blades than were previously possible with conventional parallel imaging methods. In the work we present here, we compare the imaging performance of the external calibration Propeller to conventional Cartesian and PROPELLER methods for stationary and moving volunteers. Ten volunteers were imaged under the institution IRB approved protocol and images were evaluate for diagnostic quality by a board trained radiologist on a scale from 1-5 (1 = no useful diagnostic information, 2 = limited diagnostic value but visible structures, 3 = fair quality but image quality significantly compromised, 4 = good image quality but some visible artifacts, 5 = excellent image quality with minimal if any artifacts).

A summary of the reader study evaluating imaging performance in both stationary and moving subjects is shown in Table 1. The external calibration PROPELLER with motion correction was found to maintain image quality in stationary subjects when motion correction was applied (mean = 5.0, std = 0.0) and it allowed statistically significant improvements over the other methods when the subjects were moving (mean = 3.7, std = 0.9) including Cartesian (p < 0.01) and internal calibration ( p < 0.01). The motion correction with internal calibration PROPELLER method was found to result in a statistically significant degradation of image quality compared to not applying motion correction for stationary subjects due to insufficient blade width (p < 0.01).

In conclusion, the use of shared external calibration PROPELLER T1 FLAIR was found to provide a significant increase in diagnostic quality when imaging moving subjects while not compromising image quality in stationary subjects.

The use of T1 FLAIR PROPELLER with externally calibrated parallel imaging is shown to provide a significant increase in diagnostic quality for imaging moving subjects over convetional methods.

Holmes, J, Rowley, H, Beatty, P, Brittain, J, Improved Motion Correction Capabilities for T1 FLAIR PROPELLER Using Non-Cartesian Parallel Imaging.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11034517.html