0bjective To determine the optimal contrast protocols for 64.slice spiral CT coronary angiography in order to reduce the volume of contrast injection.Methods One hundred fifty pailents scheduled to undergo 64-slice spiral CT coronary angiography were prospectively randomized into the following five groups with different injection protocols:group l:uniphasic injection without a flush;group 2:biphasic injection with a flush;group 3,group 4 and group 5:triphasic injection with a diluted contrast material with 3:7.5:5.7:3 contrast/saline ratio respectively.Attenuation was measured in the right atrium,right ventricle,left atrium,left ventricle,ascending aorta,fight coronary artery and left coronary artery and analyzed with single factor variance test(ANOVA).The quality the coronary artery images was evaluated and compared using person Chi-Square.Results The total contrast material vohme were (67.0±5.3)ml,(59.9±4.9)ml,(62.9±3.2)ml,(69.2 4±5.7)ml and(70.9 4-4.6)ml in five groups respectively(F=27.43,P<0.01).Image quali～scores of coronary arteries were significant different among five groups(X2=18.81,P<0.05).There were signiflcandy differences in artifacts of the superior vena cava among five groups(X2=31.44,P<0.01).The artifacts in the superior vena cava in group 1 was the most,and in group 2 was the least.The mean enhancement values of right and left coronary arteries in group 2 were significantly greater than those in other groups(F=2.47 and 4.10,P<0.05).The visualization of both left ventricle and right ventricle cavities W88 the best in group 3.Conclusion Biphasic injection and triphasic injection are better than uniphasic injection for 64-slice spiral CT coronary angiography and triphasic injecfion is better than biphasic injection for the visualization of both left ventricle and right ventricle cavities.

Objective To evaluate the diagnostic values of MSCT for detecting atherosclerotic plaques on New Zealand rabbits models in comparison with pathologic results. Methods Fifteen New Zealand rabbits were enrolled in this study, including 5 with balloon injury and high-fat diet ( group A), 5 with high-fat diet only (group B) and 5 with regular feed (group C). 16th week late, contrast-enhanced MSCT scan was performed in all rabbits with 16 slice MSCT (16-MSCT) in group A and 64 slice MSCT (64-MSCT) in group B and C. The CT and pathological findings were compared in a double-blind manner. The sensitivities and specificities of 16-MSCT and 64-MSCT for detecting atherosclerotic plaques were evaluated by using Fisher test and x2 test. Results Sixty and seventy-five images on 16-MSCT and 64-MSCT had corresponding pathological slices. The sensitivities for the detection of plaques on 16-MSCT and 64-MSCT were 41.5% (22/53) and 64. 9% (24/37), and spocificities of 85. 7% (6/7) and 89. 5% (34/38), respectively. Conclusions 64-MSCT has a higher sensitivity in the detection of atherosclerotic plaques than 16-MSCT. Both scanners can be used to preclude the diagnosis of atherosclerosis.

Objective To establish and evaluate two protocols for the noninvasive visualization and assessment of coronary artery bypass graft (CABG) patency on electron beam tomography (EBT).Methods Two hundred and fourteen consecutive patients who underwent coronary artery bypass graft surgery were scanned using both EBT angiography with 3-dimensional reconstruction and EBT flow study with time-density-curve analysis.Results There were 589 CABGs evaluated in this study (10 grafts were excluded because of artifacts). Among them, 133 (98.5％) of 135 arterial grafts were patent, and 345 (77.7％) of 444 saphenous-vein grafts were patent. Within 5 years or between 5 and 10 years after operation, arterial graft patency exceeded venous graft patency (P ＜ 0.001 ). Three-dimensional EBT angiography achieved higher sensitivity, specificity and accuracy (97.7％, 94.1％ and 96.7％, respectively) than did EBT flow study (88.4％, 82.4％ and 85.2％, respectively) for evaluating occlusion or patency of CABG. The intra-graft flow of patent arterial and venous grafts were 4.9 ± 2.2 mi · min-1 · g-1 and 6.9 ± 2.8 mi · min-1 · g-1,respectively (P＜0.001).Conclusion The combination of EBT three-dimensional reconstruction and flow study can be more effective in the assessment of CABG anatomy and quantification of patent CABG blood flow.

Objective To analyze the image quality of coronary arteries by dual-source computed tomography (DSCT) in children with congenital heart disease(CHD). Methods Image quality of coronary arteries were scored by two radiologists with an ordinal grading system. Score 3 or 4 was considered to be good image quality and diagnostic. Score differences among 3 groups of various baseline heart rate levels, 3 groups of various age levels and 4 coronary branches were analyzed by using ANOVA. Multiple linear regression analysis was used to test the effects of age, heart rate, tube voltage, tube current, pitch, contrast volume, contrast injection rate on the coronary image scores. Results A total of 72 consecutive patients were enrolled. 71.2% (205/288) of coronary artery branches was good enough for diagnosis. Image quality of left main coronary artery (LM, score 3.64±0.49), left anterior descending (LAD, score 2.97±0.40), right coronary artery (RCA, score of 2.82±0.70), left circumflex (LCX, score 2.76±0.73) were in a descending order (F=29.00, P<0.01). Image scores of age groups of 0--1 years old (2.80±0.65), >1--3 years old (2.81±0.74), >3--14 years old (3.58±0.52) were in an ascending order (F= 20.16,P<0.01). Image scores of heart rate groups of<100 bpm (3.54±0.56),100--150 bpm (2.86± 0.70) and >150 bpm (2.81±0.63) were in a descending order (F=16.72, P<0.01). Multiple linearregression analysis demonstrated that multiple impact factors affected image quality of LM, LAD, LCX and RCA. Age(r=0.013 ,P<0.01)and contrast volume(r=0.292, P<0.01)had positive correlation with LM score. Age(r=0.509, P<0.01) and voltage (r=0.292, P=0.011) had positive correlation with LAD score. Heart rate(r= -0.179, P<0.05) had negative correlation with LAD score. Age (r=0.063, P< 0.01) had negative correlation with LCX score. Age (r=0.486,P<0.01) and voltage (r=0.220, P<0.05) had positive correlation with RCA score. Conclusions Dual-source CT could clearly shows coronary arteries of children with CHD over the age of 3 or with heart rate less than 100 bpm. Limitations of Dual-source CT coronary angiography for CHD children included young age and fast heart rate.

Twenty-five pediatric patients (10 males,15 females) with inherited epidermolysis bullosa,aged 3-16 yr,weighing 11-29 kg,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,underwent lysis and reconstructive surgery of both hands adhesions from July 2015 to April 2017 in our hospital.Ketamine 4-6 mg/kg and atropine 0.01 mg/kg were intramuscularly injected at 20 min before admission to the operating room.Oxygen 2 L/min was inhaled by mask after admission to the operating room.Anesthesia was induced by Ⅳ injection of midazolam 0.08 mg/kg and ketamine 2 mg/kg.Pediatric patients kept spontaneous breathing.Anesthesia was maintained by Ⅳ infusion of propofol 5 mg · kg-1 · min-1 and remifentanil 0.05-0.08 μg · kg 1 · min-1.Mepitel was used to protect skin during surgery,and sodium potassium magnesium calcium and glucose injection was intravenously infused to replace the physiological requirement,blood loss and continued loss.Anesthesia time was (130±43) min,surgery time (107±42) min,the amount of intraoperative fluid infused (352± 120) ml,blood loss (29± 10) ml and emergence time (15±6) min.Intraoperative respiratory depression was found in 5 cases (20％);postoperative new bullae occured in 3 eases,and among the 3 cases,one developed on the back and the other two on the buttocks.No cardiovascular events occurred during and after surgery in this study.

Objectives To probe into electron beam computed tomography (EBCT) angiography and 3-D reconstruction of coronary artery bypass grafts (CABG) and to evaluate the clinical application of EBCT angiography and 3-D reconstruction of CABG.Methods EBCT angiography with 3-D reconstruction was achieved in 150 patients (142 men and 8 women, mean age, 57±8 years) with 399 grafts including 100 internal mammary artery grafts (IMG), 296 saphenous vein grafts(SVG) and 3 radial artery grafts (RAG) respectively. The time from bypass surgery to EBCT scanning ranged from 7 days to 120 months, averaging 15±28 months. Enhanced single slice mode (SSM) and flow studies were performed in all patients. The results of 3-D reconstruction of CABG were compared with bypass operation records and with coronary arteriograms (7 patients). Results 150 patients underwent successfully EBCT angiography and CABG 3-D reconstruction. According to 3-D reconstruction of the coronary bypass grafts with flow studies, 318 of 399 coronary bypass grafts were patent including IMG patency in 87/100 (87%), SVG in 228/296 (77%) and RAG in 3/3 (100/100). The overall patent rate was 79.7%. In 7 patients with 12 coronary bypass grafts , EBCT studies showed graft patency (7 grafts) and occlusion (5), which were confirmed by conventional graft angiography. Conclusions EBCT angiography with 3-D reconstruction is effective in providing the entire anatomic structure of coronary bypass grafts and evaluating coronary bypass graft patency. EBCT flow study can provide quantitative data for evaluating coronary bypass graft patency and for supplemental diagnosis of CABG 3-D reconstruction. EBCT angiography is a noninvasive technique that could replace conventional coronary arteriography for follow-up survey of coronary bypass surgery in future.