Feasibility of real‐time motion tracking using cine MRI during MR‐guided radiation therapy for abdominal targets

Purpose Real‐time high soft‐tissue contrast magnetic resonance imaging (MRI) from the MR‐Linac offers the best opportunity for accurate motion tracking during radiation therapy delivery via high‐frequency two‐dimensional (2D) cine imaging. This work investigates the efficacy of real‐time organ motio...

Full description

Saved in:
Bibliographic Details
Published in:Medical physics (Lancaster) 2020-08, Vol.47 (8), p.3554-3566
Main Authors: Keiper, Timothy D., Tai, An, Chen, Xinfeng, Paulson, Eric, Lathuilière, Fabienne, Bériault, Silvain, Hébert, François, Cooper, David T., Lachaine, Martin, Li, X. Allen
Format: Article
Language:English
Subjects:
Abdomen - diagnostic imaging
abdominal organ motion
Feasibility Studies
Humans
Imaging, Three-Dimensional
Magnetic Resonance Imaging
Magnetic Resonance Imaging, Cine
Motion
motion tracking with cine MRI
Movement
MRI‐guided radiation therapy
Phantoms, Imaging
Respiration
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Purpose Real‐time high soft‐tissue contrast magnetic resonance imaging (MRI) from the MR‐Linac offers the best opportunity for accurate motion tracking during radiation therapy delivery via high‐frequency two‐dimensional (2D) cine imaging. This work investigates the efficacy of real‐time organ motion tracking based on the registration of MRI acquired on MR‐Linac. Methods Algorithms based on image intensity were developed to determine the three‐dimensional (3D) translation of abdominal targets. 2D and 3D abdominal MRIs were acquired for 10 healthy volunteers using a high‐field MR‐Linac. For each volunteer, 3D respiration‐gated T2 and 2D T2/T1‐weighted cine in sagittal, coronal, and axial planes with a planar temporal resolution of 0.6 for 60 s was captured. Datasets were also collected on MR‐compatible physical and virtual four‐dimensional (4D) motion phantoms. Target contours for the liver and pancreas from the 3D T2 were populated to the cine and assumed as the ground‐truth motion. We performed image registration using a research software to track the target 3D motion. Standard deviations of the error (SDE) between the ground‐truth and tracking were analyzed. Results Algorithms using a research software were demonstrated to be capable of tracking arbitrary targets in the abdomen at 5 Hz with an overall accuracy of 0.6 mm in phantom studies and 2.1 mm in volunteers. However, this value is subject to patient‐specific considerations, namely motion amplitude. Calculation times of 
ISSN:0094-2405
2473-4209
DOI:10.1002/mp.14230