CT조영제 부작용 고위험군에 대한 전처치의 유용성

장양선(Yang seon Jang),이광원(Gwang won Lee),구양수(Yang su Ku),김대현(Dae hyeon Kim) 대한CT영상기술학회 2013 대한CT영상기술학회지 Vol.15 No.1

목적 : 조영제를 사용하는 CT검사에서 조영제 투여 전 병원 내 약물이상 반응 모니터링 팀에서 만든 조영제 부작용 관련 상병코드에 따라 조영제 부작용 고위험군에게 전처치를 시행할 경우 조영제 부작용을 감소시키고 예방할 수 있는 방안을 제공하고자 한다. 대상 및 방법 : 연구대상은 2012년 1월 1일부터 2012년 12월 31일까지 일개 대학병원에 내원한 외래환자 중 정맥내로 조영제를 투여받은 23,317명에서 조영제 부작용 고위험군에게 전처치를 시행한 남녀 118명을 대상으로 하였다. 전처치 방법으로는 스테로이드제인 Prednisolone tab 5mg 10T를 조영제 주입 13시간, 7시간, 1시간 전에 경구 투여하였으며 항히스타민제인 Cetizal tab 5mg 1T를 조영제 주입 1시간 전에 경구 투여 하였다. 또한 검사 당일 전처치가 되지 않은 환자는 마찬가지로 항히스타민제와 스테로이드제인 Chlorpeniramine 4mg/2ml, solu-cortef 250mg/2ml를 조영제 주입 30분 전에 정맥 주입하였다. 결과 : 일반적 특성에서 남자 61명(51.7%) 중 6명(5.09%), 여자 57명(48.3%) 중 3명(2.54%)으로 검사 후 부작용이 나타났으며(p=0.350), 연령에 따라서는 60세 이상에서 60명(50.8%) 중 6명(5.09%)으로 가장 많이 발생하였다(p=0.914). 촬영부위별 부작용 발생 역시 검사 후 증상과는 유의한 차이가 없었고(p=0.830) 전처치 방법으로 정맥 주입을 한 환자는 65명(55.1%) 중 6명(5.09%), 경구 투여를 한 환자는 53명(44.0%) 중 3명(2.54%)으로 유의한 차이가 없었다(p=0.467). 조영제 종류(p=0.670), 조영제 주입량(p=0.695), 주입속도(p=0.468)의 경우 검사후 증상과 유의한 차이를 보이지 않았고 조영제 부작용 기왕력의 경우 36명(30.5%) 중 6명(5.09%)이 검사후 부작용이 다시 발생되어 검사 후 증상과 유의한 차이를 보였다(p=0.001). 결론 : CT검사 후 조영제 부작용은 기왕력에 대해서 높은 관계가 있는 것으로 분석되어 과거의 기왕력을 철저히 파악하고 고위험군에게 전처치를 시행하여 검사 종료 후 세심하게 관찰하고 이를 예방할수 있는 표준화된 지침이 필요하다고 사료된다. Purpose : It is to provide the method to reduce and prevent adverse reactions to contrast media by performing pretreatment to contrast media anaphylaxis high-risk group according to contrast media anaphylaxis related illness code by drug side effect response monitoring team in hospital before the administration of contrast media. Materials and Methods : The subjects were 118 male and female patients who received pretreatment for contrast media anaphylaxis high-risk group out of 23,317 patients who came to the subject hospital and had contrast media in veins. For conditioning, Prednisolone (corticosteroid agent) tab 5 mg 10T were given 13 hours, 7 hours and 1 hour before the administration of contrast media, and Cetizal (anti-histamine) tab 5mg 1T was given orally an hour before the administration contrast media. The patients who did not get pretreatment got injection of anti-histamine agent (Chlorpeniramine 4mg/2ml) and corticosteroid agent (solu-cortef 250mg/2ml) in veins 30 minutes before the administration of contrast media. Results : In general characteristics, 6(5.09%) out of 61 males(51.7%) and 3(2.54%) out of 57 females(48.3%) showed anaphylaxis after the examination(p=0.350). According to age, the group over 60 showed the highest number of anaphylaxis as 6(5.09%) out of 60 (50.8%)(p=0.914). There was no significant difference between anaphylaxis occurrence according to examination part and symptoms after the examination(p=0.830), and there was no significant difference according to pretreatment method. Six(5.09%) out of 65(55.1%) who got intravenous injection showed anaphylaxis, while 3(2.54%) out of 53(44.0%) who got oral administration showed anaphylaxis(p=0.467). There was no significant difference according to contrast media type(p=0.670), contrast media injection volume(p=0.695), and injection speed(p=0.468), while contrast media anaphylaxis history showed significant difference as 6(5.09%) out of 36(30.5%) showed the recurrence of anaphylaxis after the examination(p=0.001). Conclusion : As adverse reactions to contrast media are analyzed to have high correlation with previous history of adverse reactions, it is very important to identify the previous history and a standardized guideline should be in place to administer pretreatment to the high-risk group and to perform close follow-up after the examination.

MDCT장비별 관전압 변화에 의한 HRCT의 선량과 Noise변화

이득열(Deuk Youl Lee),장양선(Yang Seon Jang),김영빈(Yeong Bin Kim),임상묵(Sang Muk Lim),이광원(Kwang Won Lee),조영기(Young Gi Jo) 대한CT영상기술학회 2012 대한CT영상기술학회지 Vol.14 No.1

목적 흉부CT 중 가장 많이 시행되고 있는 HRCT는 고관전압의 사용으로 피폭선량이 높아 이를 대상으로 관전압의 변화에 따라 피폭선량과 화질의 변화를 알아보고자 하며 발달된 MDCT의 장비별로도 어떠한 차이가 있는지 알아보고자 하였다. 대상 및 방법 본 연구는 Sierrrns사의 MD-16, 64, 128 ct장비의 고정관전류값, AEC의 reference mAs, pitch, kernel값 등은 모두 동일하게 하였고 장비 고유의 Collimator와 rotation time은 같게 할 수 없어 단순비교를 위해 장비고유의 값으로 설정하였고, 장비별로 관전압을 100 kVp, 120 kVp, 140 kVp로 변화시키면서 고정관전류 경우와 AEC 경우를 실험하였다. Rando phantom을 사용하여 각 영상의 Noise를 측정하였고, 선량측정은 장비에서 측정되는 DLP값으로 전체적인 유효선량을 나타내었으며 실질적으로 폐가 받는 유효선량은 Glass Dosimeter를 사용하여 측정하였다. 결과 동일 관전압에서 장비별 Noise 변화는 MD-64CT에 대해 16CT는 31.2% 증가, 128 CT는 19,4%로 감소하였다. Noise의 변화는 관전압이 100kVp에서 120kVp 증가 시 MD-6CT는 7.8%, 64CT는 7%, 128 CT는 3.9% 감소하였고, 120kVp에서 140kVp 증가 시 16CT는 6.5%, 64 CT는 4.6%, 128 CT는 3.2% 감소하였다. 장비별 전체 유효선량은 고정관전류 경우 MD-64CT보다 16CT는 5.3% 증가, 128CT는 2.9% 감소하였고, 폐의 유효선량도 8.9% 증가, 11,1% 감소하였다. MD-16CT의 관전압이 140kVp에서 120kVp 감소에 따른 전체 유효선량변화는 28.3%, 폐의 유효선량은 32.2% 감소하였고, 120kVp에서 100kVp 감소 시 31.1%, 26.4% 감소하였다. MD-64CT의 관전압이 140kVp에서 120kVp 감소에 따른 전체 유효선량변화는 33.1%, 폐의 유효선량은 33.9% 감소하였고, 120kVp에서 100kVp 감소 시 41.8%, 34.6% 감소였다. MD-128CT의 관전압이 140kVp에서 120kVp 감소에 따른 전체 유효선량변화는 34%, 폐의 유효전량은 33.3% 감소하였고, 120kVp에서 100kVp 감소 시 41.8%, 36.2% 감소하였다. 결론 본 연구를 통하여 관전압의 감소에 의한 선량감소효과가 매우 크다는 사실을 알고 MDCT장비별로 영상의 진단적 가치를 저하시키지 않는 범위 내에서 적정한 Noise값을 유지하며 관전압을 낮추어 사용한다면 환자피폭선량을 최소한으로 줄일 수 있을거라 생각된다. I. Purpose HRCT, the most commonly used chest CT, uses a high tube voltage and therefore exposes the subject to a high dose. Thus, this study purposed to examine the variation of exposure dose and image quality according to tube voltage and to analyze differences among advanced MDCT. II. Material and method This study set equally the fixed tube currency, AEC reference mAs, pitch and kernel value of MD-16, 64 and 12.8 CT manufactured by Siemens, and because collimator and rotation time could net be set equally they were set to the values specific to each MDCT for simple comparison. For each MDCT, we changed tube voltage from 100 kVp to 120 kVp and 140 kVp, and conducted experiments in case of fixed tube currency and in case of AEC. The noise of each image was measured using a Rando phantom, and for exposure doses, overall effective dose was presented in DLP and effective dose on the chest was measured with glass dosimeter. III. Result Af. the same tube voltage, noise was 31.2% higher in 16CT and 19.4% lower in 128 CT compared to that in MD-64CT. When tube voltage increased from 100 kVp to 120kVp, noise increased by 7.8% in .MD-16CT, 7% in 64CT, and 3.9% in 128 CT, and when it increased from 120kVp to 140kVp, noise increased by 6.5% in 16 CT, 4.6% in 64 CT, and 3.2% in 12.8 CT. Overall effective dose under fixed tube currency was 5.3% higher in 16CT and 2.9% lower in 12.8CT than that in MD-64CT, and effective dose on the chest was 8.9% higher and 11.1% lower, respectively. When the tube voltage of .MD-16CT decreased from 140kVp to 120 kVp, overall effective dose decreased by 28.3% and effective dose on the chest decreased by 32. 2%, and when the tube voltage decreased from 120 kVp to 100 kVp, they decreased by 31.1% and 26.4%, respectively. When the tube voltage of MD-64CT decreased from 140 kVp to 120 kVp, overall effective dose decreased by 33.1% and effective dose on the chest decreased by 33.9%, and when the tube voltage decreased from 120kVp to 100kVp, they decreased by 41.8% and 34.6%, respectively. When the tube voltage of .MD-128CT decreased from 140 kVp to 120 kVp, overall effective dose decreased by 34% and effective dose on the chest decreased by 33.3%, and when the tube voltage decreased from 120kVp to 100 kVp, they decreased by 41.8% and 36.2%, respectively. IV. Conclusion From the results of this study, we found that the decrease of tube voltage is highly effective in reducing exposure dose, and believe to minimize patients’ exposure dose by lowering tube voltage while maintaining an adequate noise level within the scope of not degrading the diagnostic value of images in each MDCT.

나선형 CT와 16 Slice MDCT의 Brain과 Abdome 검사 시 산란선에 관한 연구

윤재혁(Jae hyeok Yun),류병규(Byeong gyu Ryu),이관원(Gwang won Lee),김동수(Dong su Kim),장양선(Yang seon Jang),구양수(Yang su Ku) 대한CT영상기술학회 2008 대한CT영상기술학회지 Vol.10 No.1

Purpose The present study purposed to measure the degree of scattered ray of radiation in spiral CT and 16-Slice MDCT of brain and abdomen using Rando phantom and to examine the change in non-patients’ exposure to scattered ray according to distance between the central beam and the patient and the reduction of exposure according to the thickness of a protection outfit for shielding from radiation. Materials and methods We measured the change of scattered ray on non-patients according to distance between the brain beam of CT and the patient and the change of scattered ray according to the thickness of an apron for shielding from scattered ray, assuming a critically ill patient and an infant on Somatom Plus 4 and MDCT table at the present hospital using Rando phantom under the same setting of cerebral and abdominal CT scan parameters. In order to reduce errors in measurements, each factor was measured three times and the mean value was obtained. The height of the survey meter probe was 111.5cm, which is ordinary adults’ iliac crest level. Results A. In the result of brain test with Plus 4, the reduction rate of scattered ray at a distance of 50cm according to distance from the central beam without an apron (15.5mR) and with an apron on: 1. When Pb equivalent was 2.5mm, the reduction rate of scattered ray was 91.55% at 50cm, 94.82% at 100cm, 98.64% at 150cm, and 99.38% at 200cm. 2. When Pb equivalent was 5.0mm, the reduction rate of scattered ray was 98.50% at 50cm, 99.26% at 100cm, 99.58% at 150cm, and 99.70% at 200cm. 3. When Pb equivalent was 7.5mm, the reduction rate of scattered ray was 98.87% at 50cm, 99.37% at 100cm, 99.79% at 150cm, and 99.80% at 200cm. B. In the result of brain test with 16-Slice MDCT, the reduction rate of scattered ray at a distance of 50cm according to distance from the central beam without an apron (16.47mR) and with an apron on: 1. When Pb equivalent was 2.5mm, the reduction rate of scattered ray was 95.40% at 50cm, 97.69% at 100cm, 98.84% at 150cm, and 99.33% at 200cm. 2. When Pb equivalent was 5.0mm, the reduction rate of scattered ray was 98.54% at 50cm, 99.18% at 100cm, 98.54% at 150cm, and 99.66% at 200cm. 3. When Pb equivalent was 7.5mm, the reduction rate of scattered ray was 98.10% at 50cm, 99.55% at 100cm, 99.86% at 150cm, and 99.78% at 200cm. C. In the result of abdomen test with Plus 4, the reduction rate of scattered ray at a distance of 50cm according to distance from the central beam without an apron (61.47mR) and with an apron on: 1. When Pb equivalent was 2.5mm, the reduction rate of scattered ray was 91.52% at 50cm, 97.15% at 100cm, 98.74% at 150cm, and 99.40% at 200cm. 2. When Pb equivalent was 5.0mm, the reduction rate of scattered ray was 98.48% at 50cm, 99.19% at 100cm, 99.60% at 150cm, and 99.72% at 200cm. 3. When Pb equivalent was 7.5mm, the reduction rate of scattered ray was 98.81% at 50cm, 99.49% at 100cm, 99.71% at 150cm, and 99.82% at 200cm. D. In the result of abdomen test with 16-Slice MDCT, the reduction rate of scattered ray at a distance of 50cm according to distance from the central beam without an apron (79.47mR) and with an apron on: 1. When Pb equivalent was 2.5mm, the reduction rate of scattered ray was 96.56% at 50cm, 98.64% at 100cm, 99.34% at 150cm, and 99.69% at 200cm. 2. When Pb equivalent was 5.0mm, the reduction rate of scattered ray was 98.96% at 50cm, 99.45% at 100cm, 99.72% at 150cm, and 99.85% at 200cm. 3. When Pb equivalent was 7.5mm, the reduction rate of scattered ray was 99.56% at 50cm, 99.75% at 100cm, 99.86% at 150cm, and 99.94% at 200cm. Conclusion According to the results of this study, scattered ray decreased with the increase of distance. The scattered ray shielding effect was highest when the Pb equivalent of the radiation shielding outfit was 7.5mm. However, the reduction rate of scattered ray with a radiation shielding outfit at thickness of 5.0mm was higher (+4% on the average) than that with an outfit a