Journal of Medical Physics
ORIGINAL ARTICLE
Year
: 2007  |  Volume : 32  |  Issue : 3  |  Page : 103--107

Dose linearity and uniformity of Siemens ONCOR impression plus linear accelerator designed for step-and-shoot intensity-modulated radiation therapy


Janhavi R Bhangle, VK Sathiya Narayanan, Shrikant A Deshpande 
 Department of Radiation Oncology, Ruby Hall Clinic, Pune, India

Correspondence Address:
Janhavi R Bhangle
Department of Radiation Oncology, Ruby Hall Clinic, 40, Sassoon Road, Pune - 411 001
India

For step-and-shoot type delivery of intensity-modulated radiation therapy (IMRT), beam stability characteristics during the first few monitor units need to be investigated to ensure the planned dose delivery. This paper presents the study done for Siemens ONCOR impression plus linear accelerator before commissioning it for IMRT treatment. The beam stability for 6 and 15 MV in terms of dose monitor linearity, monitor unit stability and beam uniformity is investigated in this work. Monitor unit linearity is studied using FC65G chamber for the range 1-100 MU. The dose per MU is found to be linear for small monitor units down to 1 MU for both 6 and 15 MV beams. The monitor unit linearity is also studied with portal imaging device for the range 1-20 MU for 6 MV beam. The pixel values are within 1σ confidence level up to 2 MU; for 1 MU, the values are within 2σ confidence level. The flatness and symmetry analysis is done for both energies in the range of 1-10 MU with Kodak diagnostic films. The flatness and symmetry are found to be within 3% up to 2 MU for 6 MV and up to 3 MU for 15 MV.


How to cite this article:
Bhangle JR, Sathiya Narayanan V K, Deshpande SA. Dose linearity and uniformity of Siemens ONCOR impression plus linear accelerator designed for step-and-shoot intensity-modulated radiation therapy.J Med Phys 2007;32:103-107


How to cite this URL:
Bhangle JR, Sathiya Narayanan V K, Deshpande SA. Dose linearity and uniformity of Siemens ONCOR impression plus linear accelerator designed for step-and-shoot intensity-modulated radiation therapy. J Med Phys [serial online] 2007 [cited 2021 Jan 23 ];32:103-107
Available from: https://www.jmp.org.in/article.asp?issn=0971-6203;year=2007;volume=32;issue=3;spage=103;epage=107;aulast=Bhangle;type=0