Assessment of Radiation Dose to Eyes Lens from CT of the Head and Trunk

ABSTRACT. Radiation exposure of the patient during Computerized Axial To-mography examinations is known to be relatively high. Limited knowledge is available on doses received indirectly by organs, during diagnostic procedures. In the present study, the radiation dose to the lens of the eyes was measured from various Computerized Axial Tomography protocols for head and trunk imaging. Thermoluminescence dosimeters were used to measure organ doses in an anthropomorphic Rando Alderson phantom. The unwanted (non-useful) radiation doses delivered to the eye lens during Computerized Axial To-mography examination of head, facial bone, orbits, abdomen, chest, pelvis, neck, nasopharynx, cervical spine, lumbar spine, and sacroiliac joint were as-sessed. The following results are obtained: head scans, mean value 8.74 mGy; facial bone scans, mean value 8.03 mGy; orbital scans, mean value 61.51 mGy; abdomen scans, mean value 0.76 mGy; chest scans, mean value1.03 mGy; pelvis scans, mean value 0.46 mGy; neck scans, mean value 1.81 mGy; nasopharynx scans, mean value 8.56 mGy; cervical spine scans, mean value 6.15 mGy; lumber spine scans, mean value 0.46 mGy; and sacroiliac joint scans, mean value 0.35 mGy. The doses received by the eye lens from Com-puterized Axial Tomography examinations and general rediogaphy examina-tions are compared. It is observed that relatively high doses of unwanted ra-diations are delivered to the eye lens from Computerized Axial Tomography examinations