Self-encoded Marker for Optical Prospective Head Motion Correction in MRI
The tracking and compensation of patient motion during a magnetic resonance imaging (MRI) acqusition is an unsolved problem. For brain MRI, a promising approach recently suggested is to track the patient using an in-bore camera and a checkerboard marker attached to the patient乫s forehead. However, the possible tracking range of the head pose is limited by the locally attached marker that must be entirely visible inside the camera乫s narrow field of view (FOV). To overcome this shortcoming, we developed a novel self-encoded marker where each feature on the pattern is augmented with a 2-D barcode. Hence, the marker can be tracked even if it is not completely visible in the camera image. Furthermore, it offers considerable advantages over the checkerboard marker in terms of processing speed, since it makes the correspondence search of feature points and marker-model coordinates, which are required for the pose estimation, redundant. The motion correction with the novel self-encoded marker recovered a rotation of 18. around the principal axis of the cylindrical phantom in-between two scans. After rigid registration of the resulting volumes, we measured a maximal error of 0.39mm and 0.15. in translation and rotation, respectively. In in-vivo experiments, the motion compensated images in scans with large motion during data acquisition indicate a correlation of 0.982 compared to a corresponding motion-free reference.
Christoph Forman Murat Aksoy Joachim Hornegger Roland Bammer
Department of Radiology, Stanford University, Stanford, California, USAPattern Recognition Lab, Frie Department of Radiology, Stanford University, Stanford, California, USA Pattern Recognition Lab, Friedrich-Alexander-University Erlangen-Nuremberg,Erlangen, Germany
国际会议
北京
英文
259-266
2010-09-01（万方平台首次上网日期，不代表论文的发表时间）