Organ dose evaluation for CT scans based on in-phantom measurements / 中华放射医学与防护杂志

ABSTRACT

Objective To explore the organ doses and their distributions in different projections of CT scans.Methods The CT values were measured and the linear absorption coefficients were derived for the main organs of the anthropomorphic phantom to compare with the normal values of human beings.The radiophotoluminescent glass dosimeters were set into various tissues or organs of the phantom for mimic measurements of the organ doses undergoing the head,chest,abdomen and pelvis CT scans,respectively.Results The tissue equivalence of the phantom used in this study was good.The brain had the largest organ dose undergoing the head CT scan.The organ doses in thyroid,breast,lung and oesophagus were relatively large in performing the chest CT scan,while the liver,stomach,colon and lung had relatively hrge organ doses in abdomen CT practice.The doses in bone surface and colon exceeded by 50 mGy in a single pelvis CT scan.Conclusions The organ doses and their distributions largely vary with different projections of CT scans.The organ doses of colon,bone marrow,gonads and bladder are fairly large in performing pelvis CT scan,which should be paid attention in the practice.