Name
Abstract | ||
|---|---|---|
Surrogate-based tumor motion estimation and tracing methods are commonly used in radiotherapy despite the lack of continuous real time 3D tumor and surrogate data. In this study, we propose a method to simultaneously track the tumor and external surrogates with dynamic MRI, which allows us to evaluate their reproducible correlation. Four MRI-compatible fiducials are placed on the patient's chest and upper abdomen, and multi-slice 2D cine MRIs are acquired to capture the lung and whole tumor, followed by two-slice 2D cine MRIs to simultaneously track the tumor and fiducials, all in sagittal orientation. A phase-binned 4D-MRI is first reconstructed from multi-slice MR images using body area as a respiratory surrogate and group-wise registration. The 4D-MRI provides 3D template volumes for different breathing phases. 3D tumor position is calculated by 3D-2D template matching in which 3D tumor templates in 4D-MRI reconstruction and the 2D cine MRIs from the two-slice tracking dataset are registered. 3D trajectories of the external surrogates are derived via matching a 3D geometrical model to the fiducial segmentations on the 2D cine MRIs. We tested our method on five lung cancer patients. Internal target volume from 4D-CT showed average sensitivity of 86.5% compared to the actual tumor motion for 5 min. 3D tumor motion correlated with the external surrogate signal, but showed a noticeable phase mismatch. The 3D tumor trajectory showed significant cycle-to-cycle variation, while the external surrogate was not sensitive enough to capture such variations. Additionally, there was significant phase mismatch between surrogate signals obtained from fiducials at different locations. |
Year | DOI | Venue |
|---|---|---|
2017 | 10.1117/12.2254676 | Proceedings of SPIE |
Keywords | Field | DocType |
Dynamic MRI,lung cancer,motion management,radiation therapy | Nuclear medicine,Template matching,Artificial intelligence,Motion estimation,Surrogate data,Sagittal plane,Computer vision,Fiducial marker,Medical physics,Breathing,Dynamic contrast-enhanced MRI,Magnetic resonance imaging,Physics | Conference |
Volume | ISSN | Citations |
10135 | 0277-786X | 0 |
PageRank | References | Authors |
0.34 | 0 | 6 |
Name | Order | Citations | PageRank |
|---|---|---|---|
| Seyoun Park | 1 | 53 | 4.88 |
| Rana Farah | 2 | 13 | 4.74 |
| Steven M Shea | 3 | 0 | 0.34 |
| Erik Tryggestad | 4 | 0 | 0.68 |
| Russell Hales | 5 | 0 | 0.34 |
| Junghoon Lee | 6 | 38 | 7.21 |