Dosimetric comparison of linear accelerator-based stereotactic radiosurgery systems

SD Sharma; Sudhir Kumar; SS Dagaonkar; Geetika Bisht; S Dayanand; Reena Devi; SS Deshpande; S Chaudhary; BC Bhatt; S Kannan

doi:10.4103/0971-6203.31145

The official journal of AMPI, IOMP and AFOMP

Users online: 1099

ORIGINAL ARTICLE

Year : 2007 | Volume : 32 | Issue : 1 | Page : 18-23

Dosimetric comparison of linear accelerator-based stereotactic radiosurgery systems

SD Sharma¹, Sudhir Kumar², SS Dagaonkar³, Geetika Bisht³, S Dayanand⁴, Reena Devi⁵, SS Deshpande⁶, S Chaudhary⁶, BC Bhatt⁷, S Kannan¹
¹ Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, CT and CRS Building, Anushaktinagar, Mumbai - 400 094, India
² Radiation Safety Systems Division, Bhabha Atomic Research Centre, Trombay - 400 085, India
³ Bombay Hospital, Marine Lines, Mumbai - 400020, India
⁴ Department of Medical Physics, Tata Memorial Hospital, Mumbai - 400 012, India
⁵ Advanced Centre for Treatment Education and Research in Cancer, Navi Mumbai, India
⁶ P. D. Hinduja National Hospital, Mahim, Mumbai - 400 016, India
⁷ CSIR/BARC, CT and CRS Building, Anushaktinagar, Mumbai - 400 094, India

Correspondence Address:
S D Sharma
Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, CT and CRS Building, Anushaktinagar, Mumbai - 400 094
India

Source of Support: None, Conflict of Interest: None

Check

DOI: 10.4103/0971-6203.31145

Stereotactic radiosurgery (SRS) is a special radiotherapy technique used to irradiate intracranial lesions by 3-D arrangements of narrow photon beams eliminating the needs of invasive surgery. Three different tertiary collimators, namely BrainLab and Radionics circular cones and BrainLab micro multileaf collimator (mMLC), are used for linear accelerator-based SRS systems (X-Knife). Output factor (St), tissue maximum ratio (TMR) and off axis ratio (OAR) of these three SRS systems were measured using CC01 (Scanditronix/ Welhofer) and Pinpoint (PTW) cylindrical and Markus plane parallel ionization chambers as well as TLD and radiochromic film. Measurement results of CC01 and Pinpoint chambers were very close to each other which indicate that further reduction in volume and physical dimensions of cylindrical ionization chamber is not necessary for SRS/SRT dosimetry. Output factors of BrainLab and Radionics SRS cones were very close to each other while output factors of equivalent diameter mMLC field were different from SRS circular cones. TMR of the three SRS systems compared were very close to one another. OAR of Radionics cone and BrainLab mMLC were very close to each other, within 2%. However, OARs of BrainLab cone were found comparable to OARs of Radionics cone and BrainLab mMLC within maximum variation of 4%. In addition, user-measured similar data of other three mMLC X-Knives were compared with the mMLC X-Knife data measured in this work and found comparable. The concept of switching over to mMLC-based SRS/SRT is thus validated from dosimetric characteristics as well.

[FULL TEXT] [PDF]*

Table of Contents

Similar in PUBMED

Search Pubmed for

Search in Google Scholar for

Related articles

Citation Manager

Access Statistics

Reader Comments

Email Alert *

Add to My List *

* Requires registration (Free)

Article Access Statistics

Viewed	10524

Printed	417

Emailed	10

PDF Downloaded	984

Comments	[Add]

Cited by others	4