بررسی میزان‌ CTDIwوDLP در پروتکل‌های معمول CT دربیمارستان شهید بهشتی کاشان درسال 1393 ومقایسه آن با ‌میزان دز مرجع

نویسندگان

دانشگاه علوم پزشکی کاشان

10.22052/2.4.7

چکیده

امروزه استفاده از سی تی اسکن به‌عنوان یک نوع ابزار تشخیص، به‌طور چشمگیری افزایش یافته است. بنابراین، استفادۀ کنترل‌شده و مطابق مقررات حفاظتی به‌منظور کاهش اثرات مضر تشعشعی آن، امری ضروری است. هدف از انجام این پژوهش، اندازه‌گیری میزان دز دریافتی بیماران در پرتکل‌های معمول سی تی اسکن بود. این پژوهش در بخش رادیولوژی بیمارستان شهید بهشتی کاشان و با استفاده از دستگاه CT تک اسلایس Toshiba مدلAsteion CXGS-010A ، در گروه سنی بزرگسالان برای اندازه‌گیری دو کمیت CTDIW و DLP در پرتکل‌های معمول انجام شد. پارامترهای اسکن هر پرتکل برای 10 بیمار نرمال ثبت و با اعمال آن به دستگاه CT مقادیر میانگین CTDIW و DLP محاسبه و با حدود دز مرجع مقایسه شد. در این پژوهش، مقادیر CTDIw برای پرتکل‌های Head, PNS, Chest Abdomen, Pelvis به‌ترتیب از چپ به راست، 11/34، 67/19، 47/15، 95/13 و 08/10 میلی‌گری و DLP به‌ترتیب 67/362، 97/153، 33/307، 07/346 و 37/189 میلی‌گری سانتی‌متر بود. مقادیر CTDIW و DLPبه‌دست‌آمده در تمامی پرتکل‌ها از حدود اعلام‌شده در دستورالعمل کمیتۀ اروپایی EG و انگلستان UK کمتر و حتی در بعضی از پرتکل‌ها کمتر از نصف بود. اما در دو پرتکل Chest و Abdomen مقدار CTDIw نسبت به حدود اعلام‌شده توسطIAEA بیشتر بود که این امر به دلیل تفاوت در پارامترهای انتخابی اسکن است. برای کاهش هرچه بیشتر دز بیماران، می‌بایست در صورت امکان از میزان mAs کمتر همراه با KVp بالاتر، تعداد اسلایس کمتر، طول ناحیۀ اسکن و زمان کل اسکن کوتاه‌تری استفاده کرد.

کلیدواژه‌ها


عنوان مقاله [English]

The measurements of CTDIw and DLP in routine CT protocols and comparison with reference dose level in Kashan, Iran

نویسندگان [English]

  • Akbar Ali Asgharzadeh
  • Hosein Ali Akbari
  • Seyyed Masood Jafarpour
چکیده [English]

The use of computed tomography (CT) as a diagnostic tool has been considerably increased. Therefore, the controlled and protection-based use of the CT scan is necessary to reduce the detrimental effects of radiation. This study was carried out to determine patient dose level in routine CT protocols and measure CTDIW and DLP in routine CT protocols among adult patients in Kashan Shahid Beheshti Hospital. The CT scanner used, was a single-slice Toshiba model Asteion CXGS-10A. Scan parameters for each protocol were registered for 10 standard-sized patients. Then, the data were applied to the CT system and mean values of CTDIW and DLP were calculated. Finally, the values were compared with the reference dose level. The mean values of CTDIw and DLP for Head, PNS, Chest, Abdomen, and Pelvis protocols were 34.11, 19.67, 15.47, 13.95, 10.08 mGy and 362.67, 153.97, 307.33, 346.07, 189.37 mGy.cm, respectively. The mean values of CTDIW and DLP obtained in all protocols were less and in some of the protocols even less than half compared with the European guidelines and UK reference values. This may be probably due to the mAs and lesser length of scan area. But the mean values of CTDIw in the Chest and Abdomen protocols were greater than IAEA reported values due to reduced use of mAs in this study. To obtain the maximum reduction in patient dose, the lower mAs level with higher KVp, lesser number of slices, length of scan area, and shorter scan time are recommended.

کلیدواژه‌ها [English]

  • Computed tomography
  • Weighted computed tomography dose index
  • Dose length product
  • Reference dose level
  • Kashan
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