CT검사시 산란선에 의한 방사선피폭

• 영문명: Radiation Dose and Scatter Ray From Computed Tomography
• 발행기관: 대한CT영상기술학회
• 저자명: 김경재(Kyung Jae Kim)
• 간행물 정보: 『대한CT영상기술학회지』대한전산화단층기술학회지 제8권 제1호, 37~44쪽, 전체 8쪽
• 주제분류: 의약학 > 방사선과학
• 파일형태: PDF
• 발행일자: 2006.04.30

영문 초록

Purpose The study was designed to recognize radiation dose by scatter ray of Z axis that patient receives when examine brain CT and measured patient dose that medical team or protector in the CT room. Materials and Methods The research plan was compared to computer tomography of 5 devices that G company’s SDCT, 4 MDCT, 8 MDCT, 16 MDCTwere each 1, P company’s 40 MDCT during brain CT. first method, measured scatter ray of Z-axis at 20cm to 80cm by using ionization chamber. Second, measured by using survey meter at 50cm to 200cm in the CT room. Results 1. TheCTDI was measured on a CT dosimetric phantom by using a pencil ionization chamber for a brain CT which was 9.9mGy in SDCT(120kVp, 100mAs, 5mm section thickness) from the isocenter and 4 MDCT was 15.5mGy, 8 MDCT was 15.8mGy, 16 MDCT was 17.4mGy, 40 MDCT was 15.1mGy and total MDCT average dose rates was 15.95±1.0mGy. 2. Scatter exposure rates were obtained from scattered radiation at distances of 20cm and 80cm from the isocenter by 20cm space. It was decrement dose rates each 0.101mGy, 0.035mGy, 0.013mGy, 0.003mGy(65.3%, 62.9%, 77%) in SDCT and MDCT measured were 0.226mGy, 0.055mGy, 0.022mGy, 0.011mGy(76%, 60%, 50%). 3. Scatter ray was measured on a CT room by using a survey meter which was 0.87mR in SDCT at 50cm from the isocenter by 100mAs and 4 MDCT was measured 2.48mR, 8 MDCT was 2.73mR, 16MDCT was 2.95mR, 40 MDCT was 2.23mR. Average scatter ray dose rates was 2.59±0.3mR in total MDCT, in which compared with the SDCT was increased 66.4%. 4. Scatter exposures were measured with placement of a lead apron on the survey meter adjacent to the scanning, lead apron reduced the scattered exposure by 95.6% at distance of 50cm in SDCT and radiation reduced by 96.6% in MDCT. Scatter exposure rates were obtained from scattered radiation at distances of 100cm and 200cm from the isocenter by 50cmspace. It was reduced by 92.3%, 91.2%, 89.7% in SDCT and MDCT was measured 94.8%, 93.7%, 92.5%. Conclusion We can try reduce radiation dose because sensitive pediatric patient’s or medical team who taken by unnecessary scatter ray and so must use apron or protector during CT examination.

목차

Abstract

Ⅰ. 목적

Ⅱ. 대상 및 방법

Ⅲ. 결과

Ⅳ. 고찰

Ⅴ. 결론

참고문헌

키워드

radiation dose protector scattered radiation lead apron