Four‐dimensional MRI using three‐dimensional radial sampling with respiratory self‐gating to characterize temporal phase‐resolved respiratory motion in the abdomen. Issue 4 (14th May 2015)

• Record Type: Journal Article
• Authors: Deng, Zixin; Pang, Jianing; Yang, Wensha; Yue, Yong; Sharif, Behzad; Tuli, Richard; Li, Debiao; Fraass, Benedick; Fan, Zhaoyang
• Is Part Of: Magnetic resonance in medicine. Volume 75:Issue 4(2016)
• Page Start: 1574
• Page End: 1585
• Publication Date: 2015-05-14
• Subjects: 4D‐MRI -- 3D radial sampling -- self‐gating -- respiratory motion -- hysteresis -- radiotherapy planning; Nuclear magnetic resonance -- Periodicals; Electron paramagnetic resonance -- Periodicals; 616.07548
• DOI: 10.1002/mrm.25753
• Languages: English
• ISSNs: 0740-3194

Abstract

Abstract : Purpose: To develop a four‐dimensional MRI (4D‐MRI) technique to characterize the average respiratory tumor motion for abdominal radiotherapy planning. Methods: A continuous spoiled gradient echo sequence was implemented with 3D radial trajectory and 1D self‐gating for respiratory motion detection. Data were retrospectively sorted into different respiratory phases based on their temporal locations within a respiratory cycle, and each phase was reconstructed by means of a self‐calibrating CG‐SENSE program. Motion phantom, healthy volunteer and patient studies were performed to validate the respiratory motion detected by the proposed method against that from a 2D real‐time protocol. Results: The proposed method successfully visualized the respiratory motion in phantom and human subjects. The 4D‐MRI and real‐time 2D‐MRI yielded comparable superior–inferior (SI) motion amplitudes (intraclass correlation = 0.935) with up‐to one pixel mean absolute differences in SI displacements over 10 phases and high cross‐correlation between phase‐resolved displacements (phantom: 0.985; human: 0.937–0.985). Comparable anterior–posterior and left–right displacements of the tumor or gold fiducial between 4D and real‐time 2D‐MRI were also observed in the two patients, and the hysteresis effect was shown in their 3D trajectories. Conclusion: We demonstrated the feasibility of the proposed 4D‐MRI technique to characterize abdominal respiratory motion, which may provide valuable information for radiotherapy planning.Magn Reson Med 75:1574–1585, 2016. © 2015 Wiley Periodicals, Inc.