نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه فیزیک، دانشگاه کمیلا، کومیلا، بنگلادش

2 گروه فیزیک، دانشگاه چیتاگونگ، چیتاگونگ، بنگلادش

3 آزمایشگاه دزیکتری استاندارد دمک، مرکز علوم و فناوری هسته‌ای، نمایندگی انرژی اتمی بنگلادش، ساور، داکا، بنگلادش

4 گروه فیزیک، دانشگاه راجشاهی، راجشاهی،‌ بنگلادش

چکیده

در یک فرایند رادیو تراپی خارجی، نسبت بافت ظاهری (TPR20,10) به عنوان یک شاخص کیفی فوتونی مود استفاده قرار می‌گیرد. در کار حاضر تخمینی از TPR20,10 را با استفاده از اتاقک‌های یونش استوانه‌ای (فارمر NE2571 و PTW30013) در سه مد فوتونی انرژی بالا (۶، ۱۰ و MV ۱۵) با استفاده از شبیه‌سازی مونت کارلو و چینش تجربی ارایه کرده‌ایم. از MCNPX (نسخه 2.6.0) برای شبیه‌سازی باریکه‌های فوتونی حاصل از شتاب‌دهنده خطی Varian-2300CD استفاده شده است تا TPR20,10 بر اساس مجموعه گزارشات فنی ۳۹۸ تخمین زده شود. همین مقادیر قراردادی TPR20, 10  با اتاقک‌های فارمر NE2571 و PTW30013 به ازای شتاب‌دهنده‌های خطی پزشکی (LINAC) به طور تجربی اندازه‌گیری شده‌اند. تفاوت TPR20, 10 بین نتایج MCNPX و مقادیر تجربی به دست آمده از فارمر NE2571 در حدود 4/17 درصد،‌ 2/9 درصد و 2/5 درصد است، و به طور مشابه این تفاوت برای PTW30013 عبارت است از به ترتیب در حدود 3/89، 2/71 و 1/98 درصد مقادیر شبیه‌سازی ‌شده TPR20,10 با استفاده از MCNPX نشانگر توافق نزدیکی با نتایج تجربی است

کلیدواژه‌ها

عنوان مقاله [English]

Monte Carlo Simulation and Experimental Determination of Tissue Phantom Ratio for Photon Beams delivered from Medical Linear Accelerator

نویسندگان [English]

  • N. M. Rasel 1
  • S Purohit 2
  • M. S. Rahman 3
  • AKM M H Meaze 2
  • M. Y. Ali 4

1 Department of Physics, Comilla University, Cumilla- 3506, Bangladesh

2 Department of Physics, University of Chittagong, Chattogram- 4331, Bangladesh

3 Secondary Standard Dosimetry Laboratory, Institute of Nuclear Science & Technology, Bangladesh Atomic Energy

4 Department of Physics, University of Rajshahi, Rajshahi, Bangladesh

چکیده [English]

For an external radiotherapy procedure, the tissue phantom ratio (TPR20,10) is used as a quality index. This work presents an estimate of TPR20,10 using two cylindrical ionization chambers (NE2571 Farmer and PTW30013) in three high-energy photon modes (6, 10 and 15 MV) using both the Monte Carlo (MCNP) process and the experimental setup. The MCNP (version MCNP5) was used for the simulation of photon beams delivered by Varian-2300CD for the determination of TPR20,10 according to technical report series (TRS) 398. Again applying the same protocol TPR20,10 values were measured experimentally with NE2571 Farmer and PTW30013 chambers for the same medical linear accelerator (LINAC). The differences of TPR20, 10 between MCNP and experimental values were found for NE2571 Farmer chamber within 4.17 percent, 2.9 percent and 2.5 percent and similarly, these were within 3.89 percent, 2.71 percent and 1.98 percent at 6, 10 and 15 MV respectively for PTW30013. The TPR20,10 values simulated by our calculated MCNP demonstrated strong agreement with our experimental results.

کلیدواژه‌ها [English]

  • Tissue Phantom Ratio (TPR)
  • TRS-398
  • Monte Carlo simulation
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