Optimization of Parameters in ۱۶-slice CT- scan Protocols for Reduction of the Absorbed Dose

  • سال انتشار: 1393
  • محل انتشار: مجله فیزیک پزشکی ایران، دوره: 11، شماره: 2
  • کد COI اختصاصی: JR_IJMP-11-2_006
  • زبان مقاله: انگلیسی
  • تعداد مشاهده: 296
دانلود فایل این مقاله

نویسندگان

Shahrokh Naseri

Medical Physics Dept., Mashhad University of Medical Sciences, Mashhad,Iran

Mahdi Momen Nezhad

Medical Physics Dept., Mashhad University of Medical Sciences, Mashhad,Iran

Zahra Hozhabri

Medical Physics Dept., Kermanshah University of Medical Sciences, Kermanshah,Iran

Abbas Haghparast

Medical Physics Dept., Kermanshah University of Medical Sciences, Kermanshah,Iran

Golestan Karami

Medical Physics Dept., Kermanshah University of Medical Sciences, Kermanshah,Iran

Peyman Hejazi

Medical Physics Dept., Semnan University of Medical Sciences, Semnan, Iran

چکیده

Introduction In computed tomography (CT) technology, an optimal radiation dose can be achieved via changing radiation parameters such as mA, pitch factor, rotation time and tube voltage (kVp) for diagnostic images. Materials and Methods In this study, the brain, abdomen, and thorax scaning was performed using Toshiba ۱۶-slice scannerand standard AAPM and CTDI phantoms. AAPM phantom was used for the measurement of image-related parameters and CTDI phantom was utilized for the calculation of absorbed dose to patients. Imaging parameters including mA (۵۰-۴۰۰ mA), pitch factor (۱ and ۱.۵) and rotation time (range of ۰.۵, ۰.۷۵, ۱, ۱.۵ and ۲ seconds) were considered as independent variables. The brain, abdomen and chest imaging was performed multi-slice and spiral modes. Changes in image quality parameters including contrast resolution (CR) and spatial resolution (SR) in each condition were measured and determined by MATLAB software. Results After normalizing data by plotting the full width at half maximum (FWHM) of point spread function (PSF) in each condition, it was observed that image quality was not noticeably affected by each cases. Therefore, in brain scan, the lowest patient dose was in ۱۵۰ mA and rotation time of ۱.۵ seconds. Based on results of scanning of the abdomen and chest, the lowest patient dose was obtained by ۱۰۰ mA and pitch factors of ۱ and ۱.۵. Conclusion It was found that images with acceptable quality and reliable detection ability could be obtained using smaller doses of radiation, compared to protocols commonly used by operators.

کلیدواژه ها

Computed Tomography (CT), Absorbed Dose, optimization

اطلاعات بیشتر در مورد COI

COI مخفف عبارت CIVILICA Object Identifier به معنی شناسه سیویلیکا برای اسناد است. COI کدی است که مطابق محل انتشار، به مقالات کنفرانسها و ژورنالهای داخل کشور به هنگام نمایه سازی بر روی پایگاه استنادی سیویلیکا اختصاص می یابد.

کد COI به مفهوم کد ملی اسناد نمایه شده در سیویلیکا است و کدی یکتا و ثابت است و به همین دلیل همواره قابلیت استناد و پیگیری دارد.