Return to search

Dosimetry of very small photon fields

Several dosimetric parameters were measured for three very small radiation fields (1.5, 3, and 5 mm diameter at the machine isocenter) with a small ionization chamber and a new type of radiochromic film. The experiments were carried out on a Clinac-18 linac and the fields were shaped by specially manufactured collimators. When measuring dose profiles, the ionization chamber measurements were first corrected for response variation in off-axis direction, and then deconvolved to eliminate the blur due to the poor resolution of the chamber. The measured data agreed with Monte Carlo simulations within the established statistical uncertainties. / Dynamic stereotactic radiosurgery was carried out on the same accelerator using the very small radiation beams. The dose distributions and their displacements from the laser-defined isocenter of the linac were measured and then compared to 3-D Monte Carlo calculations. The results proved that dynamic radiosurgery with very small beams has potential for clinical use.

Identiferoai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.29463
Date January 2002
CreatorsPaskalev, Kamen A.
ContributorsPodgorsak, Ervin B. (advisor)
PublisherMcGill University
Source SetsLibrary and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada
LanguageEnglish
Detected LanguageEnglish
TypeElectronic Thesis or Dissertation
Formatapplication/pdf
CoverageMaster of Science (Department of Medical Radiation Physics.)
RightsAll items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated.
Relationalephsysno: 001945082, proquestno: MQ85814, Theses scanned by UMI/ProQuest.

Page generated in 0.0019 seconds