Estimation of Thyroid Gland Dose and Radiation Risks to Patient undergoing Computed Tomography Examinations

Abstract

Exposure to radiation over long time promotes the development of thyroid carcinoma. many of the papillary induced carcinomas of the thyroid are radiation-induced. This study was intended to estimate thyroid dose and the associated risk for thyroid cancer induced from common brain, chest and cervical spine examinations, Estimate thyroid organ dose and radiation risk of the thyroid. In this study a CT machine, NRPB software, ImPact software, ICRP, Most common types of diagnostic CT studies performed on consecutive adult patients at hospitals of Khartoum State. The data of this study were collected from Alnilain Diagnostic Center (Philips, Dual slice), Ibn Alhitham specialist (Toshiba, 4 slices) and Omdurman Military hospitals (Seimens somaton blues, 16 slice).it preformed for three organs chest, brain and cervical spine. The DLP, effective dose and thyroid dose was as fallow in Omdurman Military the chest values are (DLP=172,Effective.dose=2.40(mSv),Td.dose=1.68(mSv)), brain(DLP=610,Effective.dose=1.28(mSv),Td.dose=0.14(mSv)),c/s(DLP=38.56,Effective .dose=0.19(mSv),Td.dose=0.09(mSv))in Ibn Alhitham the chest value is (DLP=655.10 ,Effective.dose=9.17(mSv),Td.dose=6.41(mSv)),brain(DLP=756.70,Effective.dose=1.58(mSv ),Td.dose=0.17(mSv)),c/s(DLP=474.50,Effective.dose=1.47(mSv),Td.dose=6.41(mSv)) in Alnilain the chest value is (DLP=123.60, Effective.dose=1.73(mSv), Td.dose=1.21(mSv)), brain(DLP=144.50,Effective.dose=2.89(mSv),Td.dose=0.31(mSv)). In this study the radiation dose is higher in Ibn Alhutham hospital than the other two hospitals while the radiation dose in Al-nilain the lowest. The dose contribution from the chest exam to the thyroid is higher than the brain and cervical opine examination.