Purpose: Four-dimensional magnetic resonance imaging (4DMRI) is an emerging technique in radiotherapy treatment planning for organ motion quantification. In this paper, the authors present a novel 4DMRI retrospective image-based sorting method, providing reduced motion artifacts than using a standard monodimensional external respiratory surrogate. Methods: Serial interleaved 2D multislice MRI data were acquired from 24 liver cases (6 volunteers + 18 patients) to test the proposed 4DMRI sorting. Image similarity based on mutual information was applied to automatically identify a stable reference phase and sort the image sequence retrospectively, without the use of additional image or surrogate data to describe breathing motion. Results: The image-based 4DMRI provided a smoother liver profile than that obtained from standard resorting based on an external surrogate. Reduced motion artifacts were observed in image-based 4DMRI datasets with a fitting error of the liver profile measuring 1.2±0.9 mm (median ± interquartile range) vs 2.1±1.7 mm of the standard method. Conclusions: The authors present a novel methodology to derive a patient-specific 4DMRI model to describe organ motion due to breathing, with improved image quality in 4D reconstruction.
Liver 4DMRI : a retrospective image-based sorting method / C. Paganelli, P. Summers, M. Bellomi, G. Baroni, M. Riboldi. - In: MEDICAL PHYSICS. - ISSN 0094-2405. - 42:8(2015 Aug), pp. 4814-4821.
|Titolo:||Liver 4DMRI : a retrospective image-based sorting method|
PAGANELLI, CHIARA (Corresponding)
|Parole Chiave:||4DMRI; radiotherapy; retrospective sorting; time-resolved imaging; treatment planning; datasets as topic; humans; image processing, computer-assisted; information theory; liver; liver neoplasms; magnetic resonance imaging; motion; pattern recognition, automated; respiration; young adult; biophysics; radiology, nuclear medicine and imaging|
|Settore Scientifico Disciplinare:||Settore MED/36 - Diagnostica per Immagini e Radioterapia|
|Data di pubblicazione:||ago-2015|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1118/1.4927252|
|Appare nelle tipologie:||01 - Articolo su periodico|