title: Multiphase contrast-saline mixture injection with dual-flow in 64-row MDCT coronary CTA.
abstract: OBJECTIVE
  To explore the feasibility of multiphase contrast-saline mixture with dual-flow injection technique for visualization of right ventricular (RV) cavity and interventricular septum (IVS) in 64-row multidetector computed tomography (MDCT) coronary angiography.
  
  
  METHODS
  Twenty-four patients underwent coronary CT angiography (CTA) imaging with 64-row MDCT. In twelve patients (group A), 60 ml contrast medium (CM) bolus was followed by 40 ml saline, and in the other twelve patients (group B), 50 ml CM bolus was followed by 50 ml contrast-saline mixture at 60:40 ratio. The CM, saline and contrast-saline mixture flow rate were all 5.0 ml/s. Two experienced radiologists measured the CT values of ascending aorta, descending aorta, pulmonary artery and RV, rated the uniformity of RV cavity, the visualization of coronary arteries and IVS independently.
  
  
  RESULTS
  By Kappa test, agreement between the two radiologists was 0.93 and 0.86 concerning the CT value measurements and the grades of the three indexes, respectively. By t-test, the mean CT values of ascending aorta and descending aorta of the two groups had no statistical difference (t=1.459, P>0.05; t=1.619, P>0.05); while the mean CT values of pulmonary artery and RV cavity had statistical differences (t=8.316, P<0.05; t=10.372, P<0.05). By two-related rank sum test, according to the visualization of coronary arteries and the uniformity of RV cavity, there were no statistical differences (U=66.00, P>0.05; U=54.00, P>0.05); while according to the visualization of IVS, group B was better than group A (U=8.00, P<0.05).
  
  
  CONCLUSIONS
  In coronary CTA, a contrast-saline mixture after CM bolus can provide clear visualization of RV and IVS and LV without impairing coronary CTA image.
authors.affiliation: Department of Radiology, Xuanwu Hospital of Capital Medical University, Beijing, China. haipei200058@yahoo.com.cn
authors.forename: Lizhen
authors.initials: L
authors.lastname: Cao
authors.forename: Xiangying
authors.initials: X
authors.lastname: Du
authors.forename: Pengyu
authors.initials: P
authors.lastname: Li
authors.forename: Yaou
authors.initials: Y
authors.lastname: Liu
authors.forename: Kuncheng
authors.initials: K
authors.lastname: Li
mesh_terms: D000368:Aged; D003287:Contrast Media / Q000008:administration & dosage; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007269:Injections, Intra-Arterial; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012965:Sodium Chloride / Q000008:administration & dosage; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D012965:Sodium Chloride