title: Analysing the integration of MR images acquired in a non-radiotherapy treatment position into the radiotherapy workflow using deformable and rigid registration.
abstract: Our aim was to analyse the feasibility of integrating an MRI acquired in a non-radiotherapy set-up into the prostate cancer radiotherapy workflow.
  
  
  
  The MRIs of 15 prostate cancer patients, acquired with a flat table-top (MRI-flat), and with a curved tabletop (MRI-curve) were analysed. MRIs were rigidly (RIR) and non-rigidly registered (DIR) with CT images. The prostate and rectum were contoured in each image set and translated to the CT, and IMRT plans were computed taking into account structural changes after RIR and DIR (P-flatRIR, P-curveRIR and P-curveDIR). In addition the P-curveDIR was overlaid with RIR structures. Spatial overlap parameters and dose-volume histogram metrics were generated.
  
  
  
  No significant differences were observed among P-flatRIR and P-curveRIR or P-flatRIR and P-curveDIR. Median gamma-values: P-curveRIR, 95.3%; P-curveDIR, 96%, translated-P-curveDIR, 95%. DVH metrics for translated-P-curveDIR were: Dmin, 64.5Gy; Dmean, 70.06Gy; V95%, 100%. No statistically significant differences were found in the dosimetric MRI-flatDIR values.
  
  
  
  The dosimetric reproduction of treatment position image following image registration of non-radiotherapy set-up images suggests that it is feasible to integrate these images into the radiotherapy workflow.
authors.affiliation: Dpt of Radiation Oncology, Complejo Hospitalario Universitario de Albacete (CHUA), Spain. Electronic address: ssabaterm@gmail.com.
authors.forename: Sebastia
authors.initials: S
authors.lastname: Sabater
authors.affiliation: Dpt of Radiology, Complejo Hospitalario Universitario de Albacete (CHUA), Spain.
authors.forename: Maria Del Rosario
authors.initials: Mdel R
authors.lastname: Pastor-Juan
authors.affiliation: Dpt of Radiation Oncology, Complejo Hospitalario Universitario de Albacete (CHUA), Spain.
authors.forename: Roberto
authors.initials: R
authors.lastname: Berenguer
authors.affiliation: Dpt of Radiation Oncology, Complejo Hospitalario Universitario de Albacete (CHUA), Spain.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Andres
authors.affiliation: Dpt of Radiation Oncology, Complejo Hospitalario Universitario de Albacete (CHUA), Spain.
authors.forename: Marimar
authors.initials: M
authors.lastname: Sevillano
authors.affiliation: Dpt of Radiology, Complejo Hospitalario Universitario de Albacete (CHUA), Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Lozano-Setien
authors.affiliation: Dpt of Radiation Oncology, Hospital Son Espases, Palma de Mallorca, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Jimenez-Jimenez
authors.affiliation: Radiation Oncology Department, ICMHO, Hospital Clinic, University of Barcelona, IDIBAPS, Spain.
authors.forename: Angeles
authors.initials: A
authors.lastname: Rovirosa
authors.affiliation: Unidad de Medicina Molecular, Centro Regional de Investigaciones Biomédicas, Universidad de Castilla-La Mancha, Albacete, Spain; Unidad asociada de Biomedicina, UCLM-CSIC, Albacete, Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Sanchez-Prieto
authors.affiliation: Dpt of Radiation Oncology, Hospital Universitari Sant Joan, Reus, Spain.
authors.forename: Meritxell
authors.initials: M
authors.lastname: Arenas
mesh_terms: D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D050397:Radiotherapy, Intensity-Modulated; D014057:Tomography, X-Ray Computed / Q000379:methods; D057188:Workflow
keywords: Deformable registration; MRI; Radiotherapy workflow; Rigid registration