en Radiation Biology Radiation Biology تحقيق بديع Original Research <div style="text-align: justify;"><span style="font-size:10pt"><span style="text-justify:newspaper"><span style="text-kashida-space:50%"><span style="line-height:119%"><span style="font-family:Calibri"><span style="color:black"><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Background</span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-weight:bold"><span style="language:en-US">:</span></span></span></span></span> <span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:black"><span style="language:en-US">The &quot;Geant4 Application for Tomography Emission&quot; (GATE) toolkit comprises advanced open-source Monte Carlo (MC) code for use in &lrm;medical imaging and radiotherapy simulations. This study aimed to verify the GATE toolkit results against a water phantom and then to show the dose calculation capabilities of the GATE for radiotherapy. The results were compared with three dose calculation algorithms using patients&#39; Computerized Tomography (CT) data.&lrm; </span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Materials and Methods</span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-weight:bold"><span style="language:en-US">:</span></span></span></span></span> <span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:black"><span style="language:en-US">A Linac with a 6 MV photon beam was simulated in the GATE code. The &lrm;code was verified, head CT images of three patients were inserted into the GATE as realistic &lrm;phantoms&lrm;, and simulations were performed for different field sizes and angles. The Percent &lrm;Depth Doses (PDDs) and transverse profiles were extracted from the GATE simulation and &lrm;calculation &lrm;algorithms. Their results were &lrm;compared regarding the Dose Difference (DD) and gamma index for the PDDs and the Full Width at Half Maximum (FWHM) for the profiles. &lrm;</span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Results</span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-weight:bold"><span style="language:en-US">:</span></span></span></span></span> <span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:black"><span style="language:en-US">Using the patient CT data for the PDDs, the &lrm;gamma pass rate with 3%/3 mm criteria in the comparison between the GATE &lrm;simulation and &lrm;algorithms for all fields ranged from 89.4% to &lrm;&lrm;98.8%, with an average of 92.8%. The &lrm;extracted FWHMs from the GATE and algorithms were in good agreement, and their differences ranged from 0.1 to 1.2 mm. </span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Conclusions</span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-weight:bold"><span style="language:en-US">:</span></span></span></span></span> <span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:black"><span style="language:en-US">The GATE MC toolkit has good potential for implementation in radiotherapy Treatment Planning Systems (TPS) for dose calculations.</span></span></span></span></span></span></span></span></span></span></div> GATE, geant4, Monte Carlo Code, photon beam. 663 673 http://ijrr.com/browse.php?a_code=A-10-1-1096&slc_lang=en&sid=1 A.B. Yeke Dehghan 7900319475328460024874 7900319475328460024874 No Department of Medical Physics and Biomedical Engineering, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran A. Mostaar mostaar@sbmu.ac.ir 7900319475328460024875 7900319475328460024875 Yes Department of Medical Physics and Biomedical Engineering, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran P. Azadeh 7900319475328460024876 7900319475328460024876 No Department of Radiation Oncology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran