Evaluate the dose received by CT scan of the brain from the eye and thyroid

Nowadays, irradiation thyroid is very important as an acute organ in CT scans of the brain. Due to the increasing usage of CT scans for diagnosing diseases, the purpose of this Research is to evaluate the received dose from the eye and thyroid in brain CT scans.

In this research, while performing CT scan of the brain for irradiation of thyroid and eye were examined in phantom and patients by using Thermo luminescence Dosimetry dosimeter in Shahid Modares Hospital. The dosimeters were placed on the surface of the organs in the X-ray field.

In this study, the absorbed dose of sensitive eye and thyroid was read by the reader in terms of Nanocollen and then converted to mSv by using a calibration curve. In the 3 patient's brain CT scans, the average of received dose from the left eye was 29.13 mSv, the average of received dose from the right eye was 27.51 mSv and the average of received dose from thyroid was 46.08 mSv. In 3 phantom brain CT scans, the average received dose from the right eye is 26.35 mSv, the average received dose from the left phantom eye is 25.71 mSv and the average received dose from the phantom thyroid is 35.22 mSv.

According to the results, the received dose in patients and phantom are numerically close to each other. It is suggested that phantoms be used instead of the patient in dosimetry research.