Institutional Research Information Service
UCL Logo
Please report any queries concerning the funding data grouped in the sections named "Externally Awarded" or "Internally Disbursed" (shown on the profile page) to your Research Finance Administrator. Your can find your Research Finance Administrator at http://www.ucl.ac.uk/finance/research/post_award/post_award_contacts.php by entering your department
Please report any queries concerning the student data shown on the profile page to:

Email: portico-services@ucl.ac.uk

Help Desk: http://www.ucl.ac.uk/ras/portico/helpdesk
Publication Detail
In silico validation of motion-including dose reconstruction for MR-guided lung SBRT using a patient specific motion model
  • Publication Type:
  • Authors:
    Bertholet J, Eiben B, Menten M, Tran EH, Hawkes DJ, Wetscherek A, Nill S, McClelland JR, Oelfke U
  • Publisher:
  • Publication date:
  • Published proceedings:
    Proceedings of the 19th International Conference on the Use of Computers in Radiation Therapy
  • Status:
  • Name of conference:
    ICCR, 19th International Conference on the Use of Computers in Radiation Therapy
  • Conference place:
    Montreal, Canada
  • Conference start date:
  • Conference finish date:
Motion-including dose reconstruction (MIDR) aims at reconstructing the actually delivered dose to the moving anatomy during radiotherapy. Patient-specific motion models (PSMM) can be used to determine the time-resolved anatomy during treatment delivery on an MR-linac for MIDR. In this study, PSMM-based MIDR was validated for MR-guided lung SBRT. The digital XCAT phantom was used to generate a ground truth moving anatomy (GT-XCAT) based on in-vivo measured motion. Using the first 10 minutes of the motion trace, GT-XCAT volumes were subsampled to simulate pre-treatment interleaved sagittal/coronal MR acquisition with a sagittal navigator slice for breathing signal extraction. A PSMM was fitted and a motion-compensated super-resolution image (MCSRI) was reconstructed simultaneously. An MR-linac treatment plan for 3-fraction lung-SBRT was designed on a reference GT-XCAT. GT-XCATs were generated for the remainder of the motion trace. The intra-treatment time-resolved anatomy was estimated via MCSRI deformation using the PSMM and the breathing signals extracted from navigator slices sub-sampled from GT-XCATs. Treatment delivery was simulated in our in-house emulator. The treatment fluence was discretized into sub-beams, each associated with the GT or deformed-MCSRI anatomy that it was delivered to. The dose was accumulated onto the reference anatomy. For comparison, shift-MIDR was calculated emulating tumour motion as sub-beam isocenter shifts on the static reference GT-XCAT anatomy. For the plan dose, GT-MIDR, PSMM-MIDR and shift-MIDR respectively: GTV-D98% was 70.8Gy, 67.7Gy, 69.0Gy and 67.4Gy; GTV-D50% was 77.7Gy, 775.2Gy, 75.5Gy and 76.0Gy; heart-V30Gy was 48.4cc, 55.6cc, 53.0cc and 64.7cc; Oesophagus-V2% was 22.6Gy, 21.7Gy, 21.7Gy and 23.1Gy. Evaluated against GT-MIDR, PSMM-MIDR was more accurate than shift-MIDR for organ at risk (OAR) dose estimation and similar for target dose estimation. The MR-based PSMM was shown to be suitable for MIDR of the target and OAR. Shift-MIDR is not intended to correctly estimate OAR dose but may be used for target dose estimation.
Publication data is maintained in RPS. Visit https://rps.ucl.ac.uk
 More search options
UCL Researchers
Dept of Med Phys & Biomedical Eng
Dept of Med Phys & Biomedical Eng
Dept of Med Phys & Biomedical Eng
University College London - Gower Street - London - WC1E 6BT Tel:+44 (0)20 7679 2000

© UCL 1999–2011

Search by