ارزیابی تأثیر استفاده از حفاظ‌های کامپوزیتی پلی‌اورتان در کاهش خطر القای آب مروارید در تصویربرداری سی‌تی‌اسکن سر

نویسندگان

1 دانشکده علوم پزشکی تبریز

2 دانشگاه نیشابور

3 دانشگاه بیرجند

10.22052/7.4.41

چکیده

تصویربرداری سی‌تی از سر یکی از روش‌های معمول تشخیصی می‌باشد که می‌تواند باعث کدورت عدسی و القای آب مروارید شود. القای آب مروارید از اثرات قطعی پرتو است که در اثر پرتوگیری ناحیه حساس عدسی با آستانه دز   Gy0/5 اتفاق می‌افتد. اخیراً میزان دز رسیده به نواحی مختلف چشم در تصویربرداری سی‌تی ناحیه سر برآورد شده است. در این پژوهش تأثیر استفاده از حفاظ بیسموت-پلی‌اورتان بر کاهش شار و افت دز اجزای چشم بررسی می‌شود. برای این منظور از مدل چشم با آناتومی واقعی استفاده شده‌ است. پس از جایگذاری مدل درون سر فانتوم مرد بزرگسال ICRP < /span>، پرتوگیری تشخیصی سی‌تی توسط کد مونت‌کارلو MCNPX با سه ولتاژ 80، 100 و kVp < /span> 120 شبیه‌سازی شده و دز و شار حجمی رسیده به نواحی مختلف چشم بدون حفاظ و با حفاظ بیسموت پلی اورتان با غلظت‌های مختلف محاسبه گردید. در نهایت با بررسی نتایج به دست آمده و در نظر گرفتن سایر ملاحظات، حفاظ بیسموت پلی‌اورتان با غلظت %20 به عنوان انتخابی مناسب معرفی شد. نتایج نشان می دهد با استفاده از این حفاظ، در ولتاژ 80، 100 و kVp < /span> 120 دز اجزای چشم به ترتیب تا حدود 70، 65 و 60 درصد کاهش می‌یابد.
 

کلیدواژه‌ها


عنوان مقاله [English]

Evaluation of polyurethane composite shields effect on reducing the risk of cataract induction at head CT scan

نویسندگان [English]

  • Parisa Akhlaghi 1
  • Atiyeh Ebrahimi Khankook 2
  • Alireza Vejdani Noghreiyan 2
  • Keyhandokht Karimi Shahri 3
چکیده [English]

Head computed tomography is a common diagnostic examination, which may cause lenticular opacity and cataracts. Cataract induction is one of the non-stochastic effects of radiation, that happens at threshold dose of 0.5 Gy. Recent studies illustrate that only irradiation to the sensitive (germinative) zone of the lens is a prerequisite to cataract development. Recently, the dose values absorbed in substructures of a detailed eye model at head CT scan has been evaluated. In the present work, the effect of shielding on flux reduction and dose to different eye substructures was investigated. For this purpose, after placing eye model in the head of ICRP adult male phantom, CT exposure was simulated at tube voltage of 80, 100 and 120 kVp by MCNPX Monte Carlo code. Dose values as well as photon flux were estimated without and with different bismuth-polyurethane composite shields. Given its advantages, polyurethane composite with bismuth concentration of 20% was selected as an appropriate protective shield. Results show that applying this composite shield reduces dose almost 70%, 65% and 60% at tube voltages of 80, 100 and 120 kVp, respectively.
 
 

کلیدواژه‌ها [English]

  • CT examination
  • Eye model
  • Dosimetry
  • Cataract
  • Polyurethane composite shields
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