BJR
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
First published online December 6, 2006
British Journal of Radiology (2007) 80, 446-451
© 2007 British Institute of Radiology
doi: 10.1259/bjr/94582813
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Paschalis, T
Right arrow Articles by Vlachos, L
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Paschalis, T
Right arrow Articles by Vlachos, L

Full paper

Dosimetric evaluation of a new collimator insert system for stereotactic radiotherapy

T Paschalis, PhD1, P Sandilos, PhD1,2, E Tatsis, MSc1, P Karaiskos, PhD2,3, C Antypas, MSc1, C Chatzigiannis, MSc1, K Dardoufas, PhD1, E Georgiou, PhD3 and L Vlachos, PhD1

1 Department of Radiology, Medical School, University of Athens, Aretaieion Hospital, 76 Vas. Sofias Ave, 115 28 Athens, 2 Medical Physics Department, Hygeia Hospital, Kifissias Ave and Erythrou Stavrou, Marousi, 151 23 Athens, 3 Medical Physics Department, Medical School, University of Athens, 75 Mikras Asias, 115 27 Athens, Greece

Correspondence: P Sandilos, PhD, Department of Radiology, Medical School, University of Athens, Aretaieion Hospital, 76 Vas. Sofias Ave, 115 28 Athens, Greece. E-mail: p.sandilo{at}hygeia.gr

The prototype of a stereotactic collimator set developed in our department is evaluated for clinical use. This set consists of three cylindrical blocks mounted on a tray which slides in the wedge insert of a Siemens Primus accelerator. Each block has a collimating hole along its long axis to produce radiation fields of circular cross-section at the isocentre plane with diameters of 15 mm, 20 mm and 25 mm. Different geometric and dosimetric quality assurance tests were performed and results are found within the limits set for stereotactic radiotherapy. Dosimetry results measured using Kodak EDR-2 radiographic film and a pinpoint ion chamber also show good agreement with corresponding results calculated by Monte Carlo simulation of the linear accelerator head and the collimators. Measured dosimetry data were used to adapt a conventional PLATO treatment planning system for stereotactic radiotherapy using the prototype collimator set. Treatment planning system calculations and film measurements for treatment of an intracranial lesion in an anthropomorphic head phantom using coplanar 180° arcs are compared and found to agree within 2 mm. This supports the accuracy of dose delivery using the prototype stereotactic collimators. Despite their increased penumbra (2.5–3.5 mm relative to 2–2.5 mm for commercially available collimators) the ease of construction makes the proposed stereotactic collimators an interesting alternative for accomplishing cost effective stereotactic treatments.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
BJR DMFR IMAGING  ALL BIR JOURNALS 
Copyright © 2007 by the British Institute of Radiology.