برآورد مقدار S جنین در سنین مختلف بارداری ناشی از رادیوداروی پوزیترون‌زا

نویسندگان

1 خراسان رضوی، مشهد، دانشگاه فردوسی مشهد، گروه فیزیک

2 آذربایجان شرقی، تبریز، دانشگاه صنعتی سهند

چکیده

دزسنجی زن باردار تحت تصویربرداری تشخیصی با پرتوهای یون‌ساز، به‌دلیل حساسیت بالای جنین به پرتو و اثرات مخرب پرتو بر جنین بسیار مورد توجه است. در این مطالعه مقادیر S ناشی از رادیوداروی پوزیترون‌زای F-FDG18 در اندام‌های مختلف جنین با استفاده از کد مونت‌کارلوی MCNPX2.6 محاسبه شده است. برای شبیه‌سازی بدن زن باردار و جنین از فانتوم‌های هیبریدی 3، 6 و 9 ماهه استفاده شده است. نتایج نشان می‌دهد که با افزایش سن جنین، مقادیر S جنین ناشی از خودجذبی، کاهش می‌یابد. هنگامی که اندام چشمه در مجاورت جنین واقع شده است، روند کاهشی در صورتی مشاهده می‌شود که فاصله بین اندام چشمه و جنین با افزایش سن جنین افزایش یابد. مقایسه بین داده‌های محاسبه شده در این مطالعه و دیگران روند مشابهی را نشان می‌دهد، گرچه در بعضی موارد اختلاف داده‌ها به‌طور میانگین تا %40 است. این اختلاف به‌دلیل تفاوت هندسه فانتوم مورد استفاده می‌باشد. بنابراین برای تخمین دقیق‌تر دز برای بیمار باردار، تلاش بر این است که در مطالعات آینده روشی برای ساخت فانتوم وابسته به بیمار با استفاده از تعداد محدودی انداز‌ه‌گیری تبیین شود و بدین ترتیب، دقت دز محاسبه شده افزایش یابد.
 

کلیدواژه‌ها


عنوان مقاله [English]

Estimation of fetal S-value for various gestational ages from Positron-emitting radiopharmaceutical

نویسندگان [English]

  • Elie Hoseinian-Azghadi 1
  • Hashem Miri-Hakimabad 1
  • Nadia Zarghi 1
  • Najmeh Mohammadi 2
چکیده [English]

Dosimetry of a pregnant woman under diagnostic imaging with ionizing radiation is very important due to the high radiosensitivity of the fetus and the destructive effects of radiation on it. In this study, the amount of S-values induced by the positron-emitting radiopharmaceutical 18F-FDG in different fetal organs were calculated using the MCNPX2.6 Monte Carlo code. In the simulations, hybrid phantoms of 3- 6- and 9-month pregnant women were used. The results showed that with increasing the fetal age, the self S-values of fetal organs decrease. A comparison between the calculated data in this study and those reported by other studies showed similar trend, however in some cases the data difference was up to 40% on average. These differences are due to the differences between the geometry of the used phantoms. Therefore, in order to more accurately estimate the dose to pregnant patient and her fetus, we intend to introduce a method for constructing a patient-dependent phantom using a limited number of measurements in our future studies, and thus increasing the accuracy of the calculated dose.

کلیدواژه‌ها [English]

  • Dosimetry
  • Fetal phantom
  • 18F-FDG
  • PET
  • Monte Carlo
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