title: Cine EPID evaluation of two non-commercial techniques for DIBH.
abstract: OBJECTIVE
  To evaluate the efficacy of two noncommercial techniques for deep inspiration breathhold (DIBH) treatment of left-sided breast cancer (LSBC) using cine electronic portal imaging device (EPID) images.
  
  
  METHODS
  23,875 EPID images of 65 patients treated for LSBC at two different cancer treatment centers were retrieved. At the Milford Regional Cancer Center, DIBH stability was maintained by visual alignment of inroom lasers and patient skin tattoos (TAT). At the South Shore Hospital, a distance-measuring laser device (RTSSD) was implemented. For both centers,cine EPID images were acquired at least once per week during beam-on. Chest wall position relative to image boundary was measured and tracked over the course of treatment for every patient and treatment fraction for which data were acquired.
  
  
  RESULTS
  Median intrabeam chest motion was 0.31 mm for the TAT method and 0.37 mm for the RTSSD method. The maximum excursions exceeded our treatment protocol threshold of 3 mm in 0.3% of cases (TAT) and 1.2% of cases (RTSSD). The authors did not observe a clinically significant difference between the two datasets.
  
  
  CONCLUSIONS
  Both noncommercial techniques for monitoring the DIBH location provided DIBH stability within the predetermined treatment protocol parameters (<3 mm). The intreatment imaging offered by the EPID operating in cine mode facilitates retrospective analysis and validation of both techniques.
authors: Brigham and Women's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115.
authors: Christopher
authors: C
authors: Jensen
authors: Brigham and Women's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115.
authors: Jaime
authors: J
authors: Urribarri
authors: Brigham and Women's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115.
authors: Daniel
authors: D
authors: Cail
authors: Brigham and Women's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115.
authors: Joerg
authors: J
authors: Rottmann
authors: Brigham and Women's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115.
authors: Pankaj
authors: P
authors: Mishra
authors: Brigham and Women's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115.
authors: Tatiana
authors: T
authors: Lingos
authors: Brigham and Women's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115.
authors: Thomas
authors: T
authors: Niedermayr
authors: Brigham and Women's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115.
authors: Ross
authors: R
authors: Berbeco
mesh_terms: D001943:Breast Neoplasms / Q000503:physiopathology / Q000532:radiotherapy*; D062485:Breath Holding; D055615:Electrical Equipment and Supplies; D006801:Humans; D007834:Lasers; D057054:Molecular Imaging / Q000295:instrumentation*; D061089:Radiotherapy, Image-Guided / Q000295:instrumentation*