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An individualized strategy to estimate the effect of deformable registration uncertainty on accumulated dose in the upper abdomen
| Content Provider | Scilit |
|---|---|
| Author | Wang, Yibing Petit, Steven F. Osorio, Eliana Vásquez Gupta, Vikas Romero, Alejandra Méndez Heijmen, Ben J. M. |
| Copyright Year | 2018 |
| Description | Journal: Physics in Medicine & Biology In the abdomen, it is challenging to assess the accuracy of deformable image registration (DIR) for individual patients, due to the lack of clear anatomical landmarks, which can hamper clinical applications that require high accuracy DIR, such as adaptive radiotherapy. In this study, we propose and evaluate a methodology for estimating the impact of uncertainties in DIR on calculated accumulated dose in the upper abdomen, in order to aid decision making in adaptive treatment approaches. Sixteen liver metastasis patients treated with SBRT were evaluated. Each patient had one planning and three daily treatment CT-scans. Each daily CT scan was deformably registered 132 times to the planning CT-scan, using a wide range of parameter settings for the registration algorithm. A subset of 'realistic' registrations was then objectively selected based on distances between mapped and target contours. The underlying 3D transformations of these registrations were used to assess the corresponding uncertainties in voxel positions, and delivered dose, with a focus on accumulated maximum doses in the hollow OARs, i.e. esophagus, stomach, and duodenum. The number of realistic registrations varied from 5 to 109, depending on the patient, emphasizing the need for individualized registration parameters. Considering for all patients the realistic registrations, the 99th percentile of the voxel position uncertainties was 5.6 ± 3.3 mm. This translated into a variation (difference between 1st and 99th percentile) in accumulated Dmax¬ in hollow OARs of up to 3.3 Gy. For one patient a violation of the accumulated stomach dose outside the uncertainty band was detected. The observed variation in accumulated doses in the OARs related to registration uncertainty, emphasizes the need to investigate the impact of this uncertainty for any DIR algorithm prior to clinical use for dose accumulation. The proposed method for assessing on an individual patient basis the impact of uncertainties in DIR on accumulated dose is in principle applicable for all DIR algorithms allowing variation in registration parameters. |
| Related Links | http://iopscience.iop.org/article/10.1088/1361-6560/aac5c2/pdf |
| ISSN | 00319155 |
| e-ISSN | 13616560 |
| DOI | 10.1088/1361-6560/aac5c2 |
| Journal | Physics in Medicine & Biology |
| Issue Number | 12 |
| Volume Number | 63 |
| Language | English |
| Publisher | IOP Publishing |
| Publisher Date | 2018-05-17 |
| Access Restriction | Open |
| Subject Keyword | Journal: Physics in Medicine & Biology Radiology, Nuclear Medicine and Imaging Deformable Image Registration Deformable Registration Uncertainty Dose Accumulation Dose Mapping Uncertainty Liver Sbrt |
| Content Type | Text |
| Resource Type | Article |
| Subject | Radiology, Nuclear Medicine and Imaging Radiological and Ultrasound Technology |
