<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><p>A number of experiments was performed using standard protocols, in order to evaluate the dosimetric accuracy of Leksell Gamma Knife 4C unit. Verification of the beam alignment has been performed for all collimators using solid plastic head phantom and Gafchromic™ type MD-55 films. The study showed a good agreement of Leksell Gammaplan calculated dose profiles with experimentally determined profiles in all three axes. Isocentric accuracy is verified using a specially machined cylindrical aluminium film holder tool made with very narrow geometric tolerances aligned between trunnions of 4 mm collimator. Considering all uncertainties in all three dimensions, the estimated accuracy of the unit was 0.1 mm. Dose rate at the centre point of the unit has been determined according to the IAEA, TRS-398 protocol, using Unidose-E (PTW-Freiburg, Germany) with a 0.125 cc ion chamber, over a period of 6 years. The study showed that the Leksell Gamma Knife 4C unit is excellent radiosurgical equipment with high accuracy and precision, which makes it possible to deliver larger doses of radiation, within the limits defined by national and international guidelines, applicable for stereotactic radiosurgery procedures.</p></abstract>

A number of experiments was performed using standard protocols, in order to evaluate the dosimetric accuracy of Leksell Gamma Knife 4C unit. Verification of the beam alignment has been performed for all collimators using solid plastic head phantom and Gafchromic™ type MD-55 films. The study showed a good agreement of Leksell Gammaplan calculated dose profiles with experimentally determined profiles in all three axes. Isocentric accuracy is verified using a specially machined cylindrical aluminium film holder tool made with very narrow geometric tolerances aligned between trunnions of 4 mm collimator. Considering all uncertainties in all three dimensions, the estimated accuracy of the unit was 0.1 mm. Dose rate at the centre point of the unit has been determined according to the IAEA, TRS-398 protocol, using Unidose-E (PTW-Freiburg, Germany) with a 0.125 cc ion chamber, over a period of 6 years. The study showed that the Leksell Gamma Knife 4C unit is excellent radiosurgical equipment with high accuracy and precision, which makes it possible to deliver larger doses of radiation, within the limits defined by national and international guidelines, applicable for stereotactic radiosurgery procedures.

Dosimetrical evaluation of Leksell Gamma Knife 4C radiosurgery unit

Department of Neurosurgery, National Institute of Mental Health and Neuro Sciences (Deemed University), Bangalore, India

Department of Physics, University of Calicut, Kozhikode Kerala, India

Department of Radiation Physics, Kidwai Memorial Institute of Oncology, Banaglore, India

Polish Journal of Medical Physics and Engineering

{"article-title":"Dosimetrical evaluation of Leksell Gamma Knife 4C radiosurgery unit"}

A number of experiments was performed using standard protocols, in order to evaluate the dosimetric accuracy of Leksell Gamma Knife 4C unit. Verification of...

Dosimetrical evaluation of Leksell Gamma Knife 4C radiosurgery unit

Published Online: Mar 20, 2012

Page range: 105 - 120

DOI: https://doi.org/10.2478/v10013-011-0011-6

Keywords
Gamma knife, radiosurgery, dosimetry, Leksell, stereotactic, accuracy

This content is open access.

Dosimetrical evaluation of Leksell Gamma Knife 4C radiosurgery unit

Published Online: Mar 20, 2012

Page range: 105 - 120

DOI: https://doi.org/10.2478/v10013-011-0011-6

KeywordsGamma knife, radiosurgery, dosimetry, Leksell, stereotactic, accuracy

This content is open access.

Keywords
Gamma knife, radiosurgery, dosimetry, Leksell, stereotactic, accuracy