PMID- 32422577 OWN - NLM STAT- MEDLINE DCOM- 20210406 LR - 20210406 IS - 1724-191X (Electronic) IS - 1120-1797 (Linking) VI - 74 DP - 2020 Jun TI - Deep Learning model for markerless tracking in spinal SBRT. PG - 66-73 LID - S1120-1797(20)30111-3 [pii] LID - 10.1016/j.ejmp.2020.04.029 [doi] AB - Stereotactic Body Radiation Therapy (SBRT), alternatively termed Stereotactic ABlative Radiotherapy (SABR) or Stereotactic RadioSurgery (SRS), delivers high dose with a sub-millimeter accuracy. It requires meticulous precautions on positioning, as sharp dose gradients near critical neighboring structures (e.g. the spinal cord for spinal tumor treatment) are an important clinical objective to avoid complications such as radiation myelopathy, compression fractures, or radiculopathy. To allow for dose escalation within the target without compromising the dose to critical structures, proper immobilization needs to be combined with (internal) motion monitoring. Metallic fiducials, as applied in prostate, liver or pancreas treatments, are not suitable in clinical practice for spine SBRT. However, the latest advances in Deep Learning (DL) allow for fast localization of the vertebrae as landmarks. Acquiring projection images during treatment delivery allows for instant 2D position verification as well as sequential (delayed) 3D position verification when incorporated in a Digital TomoSynthesis (DTS) or Cone Beam Computed Tomography (CBCT). Upgrading to an instant 3D position verification system could be envisioned with a stereoscopic kilovoltage (kV) imaging setup. This paper describes a fast DL landmark detection model for vertebra (trained in-house) and evaluates its accuracy to detect 2D motion of the vertebrae with the help of projection images acquired during treatment. The introduced motion consists of both translational and rotational variations, which are detected by the DL model with a sub-millimeter accuracy. CI - Copyright (c) 2020 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved. FAU - Roggen, Toon AU - Roggen T AD - Varian Medical Systems Imaging Laboratory, Taefernstrasse 7, 5405 Daettwil AG, Switzerland. Electronic address: toon.roggen@varian.com. FAU - Bobic, Mislav AU - Bobic M AD - Varian Medical Systems Imaging Laboratory, Taefernstrasse 7, 5405 Daettwil AG, Switzerland. FAU - Givehchi, Nasim AU - Givehchi N AD - Varian Medical Systems Imaging Laboratory, Taefernstrasse 7, 5405 Daettwil AG, Switzerland. FAU - Scheib, Stefan G AU - Scheib SG AD - Varian Medical Systems Imaging Laboratory, Taefernstrasse 7, 5405 Daettwil AG, Switzerland. LA - eng PT - Journal Article DEP - 20200515 PL - Italy TA - Phys Med JT - Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB) JID - 9302888 SB - IM MH - Cone-Beam Computed Tomography MH - *Deep Learning MH - *Radiosurgery MH - Radiotherapy Planning, Computer-Assisted MH - Spine/diagnostic imaging/*radiation effects OTO - NOTNLM OT - Artificial intelligence OT - Deep Learning OT - Marker-less tracking OT - Motion monitoring OT - Real-time image analysis OT - Stereotactic body radiotherapy OT - Stereotactic radiosurgery COIS- Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. EDAT- 2020/05/19 06:00 MHDA- 2021/04/07 06:00 CRDT- 2020/05/19 06:00 PHST- 2019/10/31 00:00 [received] PHST- 2020/04/26 00:00 [revised] PHST- 2020/04/28 00:00 [accepted] PHST- 2020/05/19 06:00 [pubmed] PHST- 2021/04/07 06:00 [medline] PHST- 2020/05/19 06:00 [entrez] AID - S1120-1797(20)30111-3 [pii] AID - 10.1016/j.ejmp.2020.04.029 [doi] PST - ppublish SO - Phys Med. 2020 Jun;74:66-73. doi: 10.1016/j.ejmp.2020.04.029. Epub 2020 May 15.