36
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      Interpolation and extrapolation of dose measurements with different detector sizes to improve the spatial resolution of radiotherapy dosimetry as demonstrated for helical tomotherapy.

      Physics in medicine and biology
      Calibration, Film Dosimetry, Hot Temperature, Humans, Ions, Models, Theoretical, Particle Accelerators, Phantoms, Imaging, Photons, Radiation Dosage, Radiometry, methods, Radiotherapy, instrumentation, Radiotherapy Dosage, Radiotherapy Planning, Computer-Assisted, Radiotherapy, Conformal, Sensitivity and Specificity, Statistics as Topic, Tomography

      Read this article at

      ScienceOpenPubMed
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          A new technique for intensity modulated radiation therapy (IMRT) delivery is helical tomotherapy (HT). Like most IMRT delivery methods, HT utilizes many small fields as part of the treatment plan, which can be difficult to characterize. A novel technique for small field characterization, based on inter- and extrapolation of ion chamber readings, is presented in the context of HT. As a fan beam is characterized by its thickness and output factor, plane parallel chambers with different active volumes were used to scan the fan beam profiles. The fan beam thickness (FBT) can be determined from the thickness measured with the chamber by extrapolating to an infinitesimally small chamber size. The effective output was derived from the integral under the dose profile divided by the FBT. This was done for five FBTs and demonstrated a sharp fall off in dose when the FBT decreased below 8 mm. Similar techniques can be applied to other IMRT techniques to improve the characterization of various beam parameters.

          Related collections

          Author and article information

          Comments

          Comment on this article