Multi-detector Computed Tomography를 이용한 Neck 검사에서 Automatic Exposure Control을 이용한 선량의 최적화

Usefulness of Automatic Exposure Control for Dose Reduction: In Neck Study Using Multi-detector Computed Tomography

Purpose The purpose of die study was to compare diagnostic acceptability, noise and radiation exposure of neck multi-detector computed tomography(MDCT) performed with automatic exposure control(AEC) and fixed mA method. Materials and methods A 50 patient group were divided into 5 groups: used fixed mA, AEC with noise index 7.02, 9.10, 12.22 and 12.60 respectively and evaluated image quality. The CT equipment used GE 64 VCT scanners and neck organ doses were measured using Rando phantom and an optical glass dosimeter and evaluated patient’s image noise and exposure dose. Results There was no significant difference between using AEC technique and fixed mA in diagnostic acceptability and subjective noise. AEC technique resulted in radiation dose reduction of 9.5~35.4% compared with fixed mA technique at noise index 7.02~12.22 in thyroid level. Conslusion AEC method provided acceptable image noise for neck CT and judicious monitoring of radiation dose to patients has to be balanced with diagnostic image quality.