Determination of Absorbed Radiation Dose Levels of Lenses Thyroid and Oral Mucosa in Computed Tomography Imagining: Phantom Study

Year 2020, , 23 - 27, 12.01.2020

Osman Günay , Özcan Gündoğdu , Mustafa Demir , Hatice Semrin Timlioğlu İper , İhsan Kuru Doğan Yaşar Serpil Aközcan , Onur Yarar

https://doi.org/10.30934/kusbed.603335

Cited By: 2

Abstract

Objective:
Head-neck computed tomography (CT) imaging is one of
the most common tomography examinations in medical imaging. Lenses and thyroid
are among the most sensitive organs to radiation. The aim of this study was to
determine the radiation dose levels to which the patient's lens, oral mucosa, and
thyroid were during head and neck CT imaging.

Methods:
Thyroid, oral mucosa and lens areas of human
equivalent Alderson rando phantom were placed in thermoluminescence dosimeter
(TLD) dosimeters and computerized tomography imaging of head-neck of phantom
was performed in this study. A total of 18 TLD dosimetry was used in this
study. Firstly, dosimeters were calibrated. 6 of these dosimeters were placed
on the thyroid of the phantom and 4 of them were placed in the mouth and 4 of
them were in the lens. 4 dosimeters were used for background measurements

Results:
The radiation dose in TLDs placed at the center of
the lens was between 15.03 and 23.71 mSv (mean 19.83±3.93 mSv), the oral mucosa
was 10.36 to 19.47 mSv (mean 15.15±2.96 mSv), and the thyroid gland was between
11.21 and 16.73 mSv (mean 13.97±3.90 mSv).

Conclusion:
The permissible radiation dose for whole body and
eye lenses in ICRP reports is 20 mSv/year for radiation officers. Likewise,
there is no definite limit for patients, it is aimed to keep the dose level to
a minimum. Therefore, knowing the reference dose is important for imaging
planning.

Keywords

radiation dose, thyroid, lens, computed tomography, Thermoluminescence dosimeter

Bilgisayarlı Tomografi Çekimlerinde Lens Tiroid ve Oral Mukoza Absorbe Radyasyon Doz Düzeylerinin Belirlenmesi: Fantom Çalışması

Abstract

Amaç: Baş ve boyun bilgisayarlı tomografi (BT)
görüntülemesi, en sık kullanılan radyolojik incelemelerinden biridir. Birçok
hastalığın tanısında önemli rol oynar. Lens ve tiroid bezi radyasyona karşı en
duyarlı organlardandır. Bu çalışmanın amacı, BT görüntülemesi yapılan
hastaların, lens, oral mukoza ve tiroid dokusunun maruz kaldığı radyasyon
dozunun belirlenmesidir.

Yöntem:
Çalışmada, insan eşdeğeri olan Alderson Rando
fantomunun tiroid, oral mukoza, lens bölgelerine termolüminesans dozimetreleri
(TLD) yerleştirilmiş ve fantomun baş-boyun bölgesinin BT görüntülemesi
yapılmıştır. Toplam 18 adet TLD kullanılmıştır. Öncelikle dozimetrelerin
kalibrasyon işlemleri yapılmıştır. Bu dozimetrelerden 6 tanesi fantomun tiroid
bölgesine, 4 tanesi oral mukozaya, 4 tanesi de lens bölgesine
yerleştirilmiştir. 4 tane dozimetre ise arkaplan (background) ölçümleri için
kullanılmıştır.

Bulgular:
Lens merkezine yerleştirilen TLD’lerdeki radyasyon
dozu 15,03 ile 23,71 mSv arasında (ortalama 19,83±3,93 mSv), oral mukozada
10,36 ile 19,47 mSv arasında (ortalama 15,15±2,96 mSv), tiroid bezinde ise
11,21 ile 16,73 mSv arasında (ortalama 13,97±3,90 mSv) bulunmuştur.

Sonuç:
Uluslararası Radyolojik Koruma Komisyonu
(ICRP)raporlarında tüm vücut ve lensler için müsaade edilen radyasyon dozu,
radyasyon görevlilerinde 20 mSv/yıl’dır. Hastalar için kesin bir limit
olmamakla beraber, doz düzeyinin minimum tutulması amaçlanır. Bu nedenle
referans dozunun bilinmesi çekim planlaması için önemlidir.

Keywords

radyasyon dozu, göz, tiroid, bilgisayarlı tomografi, Termolüminesans dozimetreleri

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