1. Automated Contour Propagation of the Prostate From pCT to CBCT Images via Deep Unsupervised Learning
- Author
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Jean-Emmanuel Bibault, Y. Chen, Hilary P. Bagshaw, T. Leroy, Steven L. Hancock, Alexandre Escande, Mark K. Buyyounouski, Wei Zhao, Lei Xing, and Xiaokun Liang
- Subjects
Male ,Cancer Research ,Similarity (geometry) ,Computer science ,Cbct image ,Computed tomography ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Prostate cancer ,0302 clinical medicine ,Prostate ,Image Processing, Computer-Assisted ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Computer vision ,Adaptive radiotherapy ,Retrospective Studies ,Radiation ,medicine.diagnostic_test ,business.industry ,Radiotherapy Planning, Computer-Assisted ,Prostatic Neoplasms ,General Medicine ,Spiral Cone-Beam Computed Tomography ,Cone-Beam Computed Tomography ,medicine.disease ,Narrow band ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,Unsupervised learning ,Artificial intelligence ,business ,Algorithms ,Unsupervised Machine Learning - Abstract
Purpose/Objective(s) To develop and evaluate a deep unsupervised learning (DUL) framework based on a regional deformable model for automated prostate contour propagation from planning computed tomography (pCT) to cone-beam CT (CBCT). Materials/Methods A DUL model was introduced to map the prostate contour from pCT to on-treatment CBCT. The DUL framework used a regional deformable model via narrow band mapping to augment the conventional strategy. 251 anonymized CBCT images from prostate cancer patients were retrospectively selected and divided into three sets: 180 were used for training, 12 for validation, and 59 for testing. The testing dataset was divided into two Groups. Group one contained 50 CBCT volumes, with one physician-generated prostate contour on CBCT image. Group two contained 9 CBCT images, each including prostate contours delineated by four independent physicians and a consensus contour generated using the STAPLE method. Results were compared between the proposed DUL and physician-generated contours through the Dice similarity coefficients (DSC), the Hausdorff distances, and the distances of the center-of-mass. Results The average DSCs between DUL-based prostate contours and reference contours for test data in Group one and Group two-consensus were 0.83 ± 0.04, and 0.85 ± 0.04, respectively. Correspondingly, the mean center-of-mass distances were 3.52 mm ± 1.15 mm, and 2.98 mm ± 1.42 mm, respectively. Conclusion This novel DUL technique can automatically propagate the contour of the prostate from pCT to CBCT. The proposed method shows that highly accurate contour propagation for CBCT-guided adaptive radiotherapy is achievable via the deep learning technique.
- Published
- 2021