Shu Rongbao,Tong Kaijun,Wang Yuesong,et al.Tube current modulation based on the lateral chest diameter and CT value on a scout view in prospectively ECG-gated CT coronary angiography[J].Chinese Journal of Radiological Medicine and Protection,2015,35(7):550-554 |
Tube current modulation based on the lateral chest diameter and CT value on a scout view in prospectively ECG-gated CT coronary angiography |
Received:October 10, 2014 |
DOI:10.3760/cma.j.issn.0254-5098.2015.07.018 |
KeyWords:Coronary vessels Radiation dose Quality control Computed tomography |
FundProject:马鞍山市科技局科技计划项目(2012-k-z-04) |
Author Name | Affiliation | Shu Rongbao | Department of Imaging, the People's Hospital of Maanshan, 243000, China | Tong Kaijun | Department of Imaging, the People's Hospital of Maanshan, 243000, China | Wang Yuesong | 243000, 马鞍山市人民医院心内科 | Yan Fang | Department of Imaging, the People's Hospital of Maanshan, 243000, China | Luo Xiao | Department of Imaging, the People's Hospital of Maanshan, 243000, China | Dong Xuebin | 243000, 马鞍山市人民医院心内科 | Zhou Huafei | Department of Imaging, the People's Hospital of Maanshan, 243000, China | Zhang Cong | Department of Imaging, the People's Hospital of Maanshan, 243000, China |
|
Hits: 3952 |
Download times: 3157 |
Abstract:: |
Objective To investigate the clinical value of the patient's individually tube current modulation based on the lateral chest diameter(LD)and average CT value(CTchest)on a scout view in prospectively ECG-gated CT coronary angiography (PG CTCA). Methods Totally 194 consecutive patients were randomly divided into three groups:Group RG (retrospectively ECG-gated CTCA, 69 patients, standard protocol with a fixed 600 mA), Group PG1(prospectively ECG-gated CTCA, 68 patients) and PG2 (the control group, 57 patients). On the scout AP view, the chest LD was measured at the upper border of T10 vertebra; and the density (CTchest) was measured at the intercostal space of right midclavicular line above the diaphragm. The chest anteroposterior diameter(APD) were measured at the same level on the scout lateral view. The CTCA image noise was measured at the root of ascending aorta. A tube current conversion formula and quick list were conducted after matching the measured parameters with the noise. The tube current (mA) used in PG1 was determined by the list established previously. The tube current used in group PG2 wad fixed with reference to body mass (400 mA when < 77 kg; 500 mA when ≥77 kg). The image quality scores, image noise,volume CT dose index(CTDIvol), and effective dose(E) were evaluated for each patient.LD, CTchest, CTDIvol,DLP,E and image noise were all analyzed using one-way ANOVA analysis among 3 groups.And the image quality scores of the coronary artery were analyzed using R×2 contingency tables χ2 test. Results The tube current conversion formula was as mA=600/282 ·(0.487LD+0.064CTchest +13.7)2 (R2=0.53, F=36.13, P=0.00). There were no statistical differences among three groups in LD and CTchest on the scout view(P > 0.05). There were magnificent statistical differences among three groups in SD, mA, and CTDIvol (F=44.96,167.37, 1 071.26,P<0.05),There were also no statistical difference on image quality scores and the assessable vessels among 3 groups(χ2=6.89,2.54,P > 0.05).Conclusions Using the tube current determined by the individual chest LD and CTchest on the scout AP view would help to control the radiation in PG CTCA without damage of image quality and diagnostic accuracy. |
HTML View Full Text View/Add Comment Download reader |
Close |
|
|
|