@article{ToussaintRichterManteletal.2016,
  author    = {Toussaint, Andr{\´e} and Richter, Anne and Mantel, Frederick and Flickinger, John C. and Grills, Inga Siiner and Tyagi, Neelam and Sahgal, Arjun and Letourneau, Daniel and Sheehan, Jason P. and Schlesinger, David J. and Gerszten, Peter Carlos and Guckenberger, Matthias},
  title     = {Variability in spine radiosurgery treatment planning - results of an international multi-institutional study},
  series = {Radiation Oncology},
  volume    = {11},
  journal   = {Radiation Oncology},
  number    = {57},
  doi       = {10.1186/s13014-016-0631-9},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146687},
  year      = {2016},
  abstract  = {Background The aim of this study was to quantify the variability in spinal radiosurgery (SRS) planning practices between five international institutions, all member of the Elekta Spine Radiosurgery Research Consortium. Methods Four institutions provided one representative patient case each consisting of the medical history, CT and MR imaging. A step-wise planning approach was used where, after each planning step a consensus was generated that formed the basis for the next planning step. This allowed independent analysis of all planning steps of CT-MR image registration, GTV definition, CTV definition, PTV definition and SRS treatment planning. In addition, each institution generated one additional SRS plan for each case based on intra-institutional image registration and contouring, independent of consensus results. Results Averaged over the four cases, image registration variability ranged between translational 1.1 mm and 2.4 mm and rotational 1.1° and 2.0° in all three directions. GTV delineation variability was 1.5 mm in axial and 1.6 mm in longitudinal direction averaged for the four cases. CTV delineation variability was 0.8 mm in axial and 1.2 mm in longitudinal direction. CTV-to-PTV margins ranged between 0 mm and 2 mm according to institutional protocol. Delineation variability was 1 mm in axial directions for the spinal cord. Average PTV coverage for a single fraction18 Gy prescription was 87 ± 5 \%; Dmin to the PTV was 7.5 ± 1.8 Gy averaged over all cases and institutions. Average Dmax to the PRV_SC (spinal cord + 1 mm) was 10.5 ± 1.6 Gy and the average Paddick conformity index was 0.69 ± 0.06. Conclusions Results of this study reflect the variability in current practice of spine radiosurgery in large and highly experienced academic centers. Despite close methodical agreement in the daily workflow, clinically significant variability in all steps of the treatment planning process was demonstrated. This may translate into differences in patient clinical outcome and highlights the need for consensus and established delineation and planning criteria.},
  language  = {en}
}
@article{HardcastleTomeCannonetal.2012,
  author    = {Hardcastle, Nicholas and Tom{\´e}, Wolfgang A. and Cannon, Donald M. and Brouwer, Charlotte L. and Wittendorp, Paul W. H. and Dogan, Nesrin and Guckenberger, Matthias and Allaire, St{\´e}phane and Mallya, Yogish and Kumar, Prashant and Oechsner, Markus and Richter, Anne and Song, Shiyu and Myers, Michael and Polat, B{\"u}lent and Bzdusek, Karl},
  title     = {A multi-institution evaluation of deformable image registration algorithms for automatic organ delineation in adaptive head and neck radiotherapy},
  series = {Radiation Oncology},
  volume    = {7},
  journal   = {Radiation Oncology},
  number    = {90},
  doi       = {10.1186/1748-717X-7-90},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134756},
  year      = {2012},
  abstract  = {Background: Adaptive Radiotherapy aims to identify anatomical deviations during a radiotherapy course and modify the treatment plan to maintain treatment objectives. This requires regions of interest (ROIs) to be defined using the most recent imaging data. This study investigates the clinical utility of using deformable image registration (DIR) to automatically propagate ROIs. Methods: Target (GTV) and organ-at-risk (OAR) ROIs were non-rigidly propagated from a planning CT scan to a per-treatment CT scan for 22 patients. Propagated ROIs were quantitatively compared with expert physician-drawn ROIs on the per-treatment scan using Dice scores and mean slicewise Hausdorff distances, and center of mass distances for GTVs. The propagated ROIs were qualitatively examined by experts and scored based on their clinical utility. Results: Good agreement between the DIR-propagated ROIs and expert-drawn ROIs was observed based on the metrics used. 94\% of all ROIs generated using DIR were scored as being clinically useful, requiring minimal or no edits. However, 27\% (12/44) of the GTVs required major edits. Conclusion: DIR was successfully used on 22 patients to propagate target and OAR structures for ART with good anatomical agreement for OARs. It is recommended that propagated target structures be thoroughly reviewed by the treating physician.},
  language  = {en}
}