PMID- 28651599
OWN - NLM
STAT- MEDLINE
DCOM- 20180426
LR  - 20220409
IS  - 1748-717X (Electronic)
IS  - 1748-717X (Linking)
VI  - 12
IP  - 1
DP  - 2017 Jun 26
TI  - Dosimetric evaluation of synthetic CT for magnetic resonance-only based 
      radiotherapy planning of lung cancer.
PG  - 108
LID - 10.1186/s13014-017-0845-5 [doi]
LID - 108
AB  - BACKGROUND: Interest in MR-only treatment planning for radiation therapy is 
      growing rapidly with the emergence of integrated MRI/linear accelerator 
      technology. The purpose of this study was to evaluate the feasibility of using 
      synthetic CT images generated from conventional Dixon-based MRI scans for 
      radiation treatment planning of lung cancer. METHODS: Eleven patients who 
      underwent whole-body PET/MR imaging following a PET/CT exam were randomly 
      selected from an ongoing prospective IRB-approved study. Attenuation maps derived 
      from the Dixon MR Images and atlas-based method was used to create CT data 
      (synCT). Treatment planning for radiation treatment of lung cancer was optimized 
      on the synCT and subsequently copied to the registered CT (planCT) for dose 
      calculation. Planning target volumes (PTVs) with three sizes and four different 
      locations in the lung were planned for irradiation. The dose-volume metrics 
      comparison and 3D gamma analysis were performed to assess agreement between the 
      synCT and CT calculated dose distributions. RESULTS: Mean differences between PTV 
      doses on synCT and CT across all the plans were -0.1% +/- 0.4%, 0.1% +/- 0.5%, and 
      0.4% +/- 0.5% for D95, D98 and D100, respectively. Difference in dose between the 
      two datasets for organs at risk (OARs) had average differences of 
      -0.14 +/- 0.07 Gy, 0.0% +/- 0.1%, and -0.1% +/- 0.2% for maximum spinal cord, lung V20, 
      and heart V40 respectively. In patient groups based on tumor size and location, 
      no significant differences were observed in the PTV and OARs dose-volume metrics 
      (p > 0.05), except for the maximum spinal-cord dose when the target volumes were 
      located at the lung apex (p = 0.001). Gamma analysis revealed a pass rate of 
      99.3% +/- 1.1% for 2%/2 mm (dose difference/distance to agreement) acceptance 
      criteria in every plan. CONCLUSIONS: The synCT generated from Dixon-based MRI 
      allows for dose calculation of comparable accuracy to the standard CT for lung 
      cancer treatment planning. The dosimetric agreement between synCT and CT 
      calculated doses warrants further development of a MR-only workflow for 
      radiotherapy of lung cancer.
FAU - Wang, Hesheng
AU  - Wang H
AUID- ORCID: 0000-0003-2313-1823
AD  - Department of Radiation Oncology, New York University School of Medicine, Langone 
      Medical Center, New York, NY, USA. wangh15@nyumc.org.
FAU - Chandarana, Hersh
AU  - Chandarana H
AD  - Bernard and Irene Schwartz Center for Biomedical Imaging, Department of 
      Radiology, New York University School of Medicine, New York, NY, USA.
FAU - Block, Kai Tobias
AU  - Block KT
AD  - Bernard and Irene Schwartz Center for Biomedical Imaging, Department of 
      Radiology, New York University School of Medicine, New York, NY, USA.
FAU - Vahle, Thomas
AU  - Vahle T
AD  - Bernard and Irene Schwartz Center for Biomedical Imaging, Department of 
      Radiology, New York University School of Medicine, New York, NY, USA.
AD  - Siemens Healthcare GmbH, Erlangen, Germany.
FAU - Fenchel, Matthias
AU  - Fenchel M
AD  - Siemens Healthcare GmbH, Erlangen, Germany.
FAU - Das, Indra J
AU  - Das IJ
AD  - Department of Radiation Oncology, New York University School of Medicine, Langone 
      Medical Center, New York, NY, USA.
LA  - eng
PT  - Journal Article
PT  - Randomized Controlled Trial
DEP - 20170626
PL  - England
TA  - Radiat Oncol
JT  - Radiation oncology (London, England)
JID - 101265111
SB  - IM
MH  - Adult
MH  - Aged
MH  - *Algorithms
MH  - Feasibility Studies
MH  - Female
MH  - Follow-Up Studies
MH  - Humans
MH  - Lung Neoplasms/diagnostic imaging/pathology/*radiotherapy
MH  - Magnetic Resonance Imaging/*methods
MH  - Male
MH  - Middle Aged
MH  - Positron Emission Tomography Computed Tomography/*methods
MH  - Prognosis
MH  - Prospective Studies
MH  - Radiotherapy Dosage
MH  - Radiotherapy Planning, Computer-Assisted/*methods
MH  - Radiotherapy, Intensity-Modulated/*methods
PMC - PMC5485621
OTO - NOTNLM
OT  - Lung cancer
OT  - MR-only radiotherapy
OT  - Radiotherapy treatment planning
OT  - Synthetic CT
COIS- The data used in this manuscript were retrospectively obtained from an 
      IRB-approved study. All the image data was de-identified by anonymization and 
      analyzed retrospectively. CONSENT FOR PUBLICATION: Not applicable. COMPETING 
      INTERESTS: The authors declare that they have no competing interests. PUBLISHER'S 
      NOTE: Springer Nature remains neutral with regard to jurisdictional claims in 
      published maps and institutional affiliations.
EDAT- 2017/06/28 06:00
MHDA- 2018/04/27 06:00
PMCR- 2017/06/26
CRDT- 2017/06/28 06:00
PHST- 2016/11/29 00:00 [received]
PHST- 2017/06/20 00:00 [accepted]
PHST- 2017/06/28 06:00 [entrez]
PHST- 2017/06/28 06:00 [pubmed]
PHST- 2018/04/27 06:00 [medline]
PHST- 2017/06/26 00:00 [pmc-release]
AID - 10.1186/s13014-017-0845-5 [pii]
AID - 845 [pii]
AID - 10.1186/s13014-017-0845-5 [doi]
PST - epublish
SO  - Radiat Oncol. 2017 Jun 26;12(1):108. doi: 10.1186/s13014-017-0845-5.