Objective To evaluate the clinical effect of intervertional devascularization and surgical devascularization in treatment of patients with upper gastrointestinal hemorrhage .Methods Ninety-nine cases treated with intervertional devaacularization or surgical devascularization were retrospectively studied including 48 cases in intervertional group and 51 cases in surgical group.The postoperative resection, complications and rebleeding time were compared by X2 test and t test between two methods.Results The 12 months, 24 months and 36 months cumulative rebleeding rates after intervertional devascularization were 12.5% (6/47) ,24.5% (11/45), 27.9% (12/43) respectively.The rate after surgical devaacularization were 29.2% (14/48) ,44.7% (21/47), 48.9% (22/45) respectively.There were statistically significant differences between the intervertional and surgical groups (X2=3.843,4.150,4.083, P < 0.05).The complications of intervertional devascularization included fever 85.4% (41/48), bellyache 81.3% (39/48), portalvein thrombosis 4.2% (2/48), intraabdominal hemorrhage 2.1% (1/48), infection 2.1% (1/48) and death 2.1% (1/48).The complications of surgical devaacularization included fever 68.6% (35/51), bellyache 62.7% (32/51), generous hydroperitoneum 25.5% (13/51), portalvein thrombosis 37.3% (19/51), splenic vein thrombosis 11.8% (6/51), hepatic encephalopathy 3.9% (2/51), hepatorenal syndrome 2.0% (1/51), intraabdominal hemorrhage 2.0% (1/51), death 3.9% (2/51) and infection 15.7% (8/51).There were statistically significant differences of fever, bellyache, generous hydroperitoneum, portalvein thrombosis, splenic vein thrombosis between the intervertional and surgical groups(X2=4.174,3.098,16.199,6.011,5.536,14.085,P <0.05).Conclusions The intervertional devascularization procedure is simple, safe and effective method for treating upper gastrointestinal hemorrhage for portal hypertensive.The clinical effect is better than that of surgical devascularization.

Objective To characterize the regular and the dynamic contrast enhancement MR imaging in choroidal hemangioma.Methods MR imaging findings of 30 cases (31eyes, 32 lesions) with choroidal hemangioma confirmed by follow-up results were retrospectively analyzed.Among them, postcontrasted T1-weighted imaging was performed in 30 patients and dynamic contrast enhancement scanning was performed in 26 cases.MRI findings and the time-intensity curve of dynamic contrast enhancement were analyzed.Results Among the 32 choroidal hemangiomas, 26 of them were at the temporal side of optic disc and 28 lesions were fusiform.Before enhancement, 23 lesions showed isointense T1-weighted signal and 31 lesions were isointense on T2-weighted imaging.All the lesions showed strong enhancement on postcontrast T1-weighted imaging, including 31 homogenously enhanced lesions and one heterogeneously enhanced lesion.Retinal detachments were found in 18 eyes.Fill-in sign were observed in 12 lesions during dynamic contrast enhancement.The time-intensity curve of dynamic contrast enhancement in 28 lesions suggested a pattern with rapid enhancement and slow washout, time to peak (91.00±25.27) s, slope ratio 3.03±1.13, the median of washout ratio 17.06%, enhancement ratio 2.87±0.79.Conclusion MRI showed a few features of the location, shape, signal characteristics, and enhancement pattern in choroidal hemangioma, which may contribut to diagnosis and treatment plan of this disease.

Objective To explore the optimal reconstruction windows in patients with heart rate (HR) over 91 (beats per minute) bpm, and to explore the feasibility of prospective ECG-gated DSCT coronary angiography.Methods Two hundred and thirty-two patients[body mass index (BMI):23-25 kg/m2, with stable HR, and average HR ≥91 bpm]with suspected or known coronary artery disease underwent retrospective ECG-gated DSCT coronary angiography.They were divided into 3 groups (A-C) according to the average HR of scanning.Images were reconstructed from 29% to 80% of the R-R interval in 3% increments.Two independent readers assessed the overall image quality by a five-point scale and determined the optimal reconstruction windows of each coronary segment and the ranges.Coronary arteries were segmented according to the guideline of the American Heart Association (AHA).The degree of interobserver agreement was determined by Kappa statistics.Results Three thousand three hundred and fortythree segments were considered to have diagnostic image quality in 232 patients.The ranges of optimal reconstruction windows of images were concentrated on 81%-61% and 51%-31%.In group A(91-95 bpm), there were 1183 segments in 83 patients, and the according proportions were 5.49%, 94.51%,respectively; In group B(96-100 bpm), there were 986 segments in 68 patients, and the according proportions were 0.20%, 99.80%, respectively; In group C(≥ 101 bpm), there were 1174 segments in 81 patients, and the according proportions were 0.17%, 99.83%, respectively.The optimal construction windows in 3274 segments out of 3343 segments in 232 patients were concentrated in 41%, ranged from 51%-31%.The image quality assessment in 3343 segments in 232 patients have a high inter-observe agreement (Kappa=0.883,P <0.05).Conclusion The optimal reconstruction windows of patients with stable HR(≥91 bpm) was concentrated in 41%, ranged from 51%-31%.When nothing except the window of data acquisition is considered, the prospective ECC,-gated DSCT coronary angingraphy can be used in patients with stable HR(≥91 bpm).

Objective To investigate the accuracy of low-dose dual-source computed tomography (DSCT) coronary angiography in the step-and-shoot (SAS) mode for the diagnosis of coronary artery stenosis in comparison with conventional coronary angingraphy (CCA).Methods Prospective multiple-center study, 46 patients[mean age(58±9) years;bedy mass index(BMI) (25±3) kg/m2]underwent both DSCT in the SAS mode and CCA within 14 days.The inclusion criteria for contrast-enhanced CT: (1) heart rate less than 65 times/rain (bpm).(2) regular sinus rhythm, heart rate fluctuations within the range of 6 bpm. (3) holding breath well, breath-hold time is about 12-15 s.The exclusion criteria:(1) allergy to iodinecontaining contrast medium, nephropathy (serum creatinine level 120 μmol/L), heart failure and serious arrhythmias.(2) patients with coronary stents or bypass grafts.(3) heart rate can not be controlled very well (4)the patient could not take nitroglycerin.(5)BMI 30 kg/m2.(6) other heart disease: carcliomyopathy, valvular disease etc.Sensitivity, specificity, negative (NPV) and positive predictive value (PPV) were determined with CCA as standard of reference.The Kappa value between the two modalities and the two observers was calculated.Radiation dose values were measured.Results Mean heart rate during scanning was (61±6)bpm.99.19% (614/619) coronary segments were depicted with a diagnostic image quality. The vessel-based sensitivity, specificity, PPV, and NPV for the diagnosis of coronary artery stenosis were 96.2% (75/78), 88.2% (60/68), 90.4% (75/83), and 95.2% (60/63), respectively.The Kappa value between the two modalities was 0.848 (P=0.000).The mean effective dose of the SAS-CTCA was (2.95± 0.96) rosy(1.26-4.32 mSy).Conclusion In selected patients, DSCT coronary angiography in the SAS mode have good image quality, which allows for the accurate diagnosis of coronary stenosis at a low radiation dose.

Objective To evaluate low-dose CT coronary angiography with prospective electrocardiogram (ECG)-triggering using dual-source CT scanner.Methods Sixty-eight patients who underwent coronary CT angiography using a dual-source CT scanner were divided into 2 groups: group A (38 cases) and group B (30 cases).Prospective ECG-triggering sequence scan mode was employed for group A.Inclusion criteria included: heart rate <70 bpm, sinus rhythm, and heart rate fluctuation less than 10 bpm.Data acquisition was set at 70% of the RR-interval.Retrospective ECG-gating helical scan was performed for group B.Inclusion criteria included heart rates < 70 bpm and sinus rhythm.The exclusion criteria included heart failure and serious arrhythmias.In both groups, patients with a BMI≥24 kg/m2 were examined with a tube voltage of 120 kV, whereas patients with a BMI <24 kg/m2 were examined with a tube voltage of 100 kV.All images were transferred to a workstation for further processing and analysis.The imaging quality was evaluated.The imaging quality of coronary artery segments were compared with rank sum test between the two groups, and the radiation dose were compared with t test.Results A total of 476 coronary artery segments were evaluated in group A and 372 segments were evaluated in group B.The mean score of imaging quality for coronary artery segments in group A was 3.48±0.59 and that in group B was 3.53±0.58.There was no statistical difference in imaging quality between the two groups (Z=-1.432, P=0.187).The effective dose was on average (2.51±0.54) mSv (range 1.3--3.3 mSv) in group A, whereas on average (14.55±3.54) rosy (range 7.1--20.2 mSv) in group B.There was a statistical difference between the two groups (t=18.484, P=0.000).Conclusions Low-dose prospective ECG-triggering sequence scan in dual-source CT coronary angiography is feasible in patients with low heart rate and regular cardiac rhythm.This scan mode can substantially reduce radiation doses while preserving good diagnostic image quality.

Objective To evaluate the value of reducing radiation dose with ECG-pulsing and image quality in 64-row multi-alice CT coronary angiography.Methods Fifty-nine consecutive patients whose heart rates were less than 80 beat per minute and cardiac rhythm was regular were randomly divided into two groups from October 26, 2007 to March 12, 2008.Conventional technique of CT coronary angiography was employed in group 1, while ECG-pulsing technique was applied in group 2.CT dose index volume (CTDIvol) and dose length product (DLP) were obtained automatically, and then the corresponding effective dose (ED) were calculated.The quality scores were performed on obtained imaging by using double blind method.Student t-test was applied in the comparison of value of CTDIvol, value of ED and quality of imagiugbetween two groups.Results The value of CTDIvol was (70.0±1.1) and (39.0±2.7) mGy, the value of ED was (16.8±2.0) and (9.5±1.7) rosy in group 1 and group 2, respectively, which reached statistically significant differences between the groups(t=57.675,15.346 ,P <0.01, respectively). The quality scores of coronary images were 3.8±0.2 and 3.8±0.1 in the groups, which did not reach the statistical significance (t=-0.222, P 0.05).Conclusions The proper application of ECG-Pulsing technology in 64-slice spiral CT coronary angiography can reduce radiation dose significantly while having no influence on the quality of the imaging.

Objective To investigate the value of MR DWI in comparing inflammatory with metastastic lymph node in animal models of lymph disease.Methods Eighteen rabbits with benign lymphadenopathy and 9 rabbits with malignant lymphadenopathy underwent routine MRI and DWI examination.Independent-samples t test was used to compare the sizes and apparent diffusion coefficient (ADC) values between the two groups.Results Thirty-four inflammatory lymph nodes and 18 metastastic lymph nodes were observed .The size of lymph nodes was (8.14±2.79) and (6.29±1.48) mm in the benign and malignant groups, respectively.There was no significant statistical difference between the sizes of the two groups (t=2.624, P 0.05).Mean ADC value of lymph nodes was (1.19±0.31)×10-3mm2/s and (1.31±0.27)×10-3mm2/s in the benign and malignant groups, respectively.There was no significant statistical difference between the ADC values of benign and malignant lymph nodes (t=1.449,P 0.05).Conclusion DWI sequence can be used to show lymphadenopathy, but the ADC value is insufficient to differentiate benign lymph nodes from malignant lymphadenopathy.

Objective To investigate the feasibility of reduced radiation dose for CT pulmonary angiography (CTPA) and the possible lowest radiation threshold by a phantom study.Methods The CT value difference between air within the trachea and the extracorporeal background region was measured in132 consecutive patients.A noise-measurement phantom and a pulmonary embolism (PE) phantom were made of phenol-formaldehyde, and both phantoms and a water phantom were scanned with standard and lower radiation doses as follow: 280, 200, 160, 100, 90, 80, 70, 60, 50, 40, 30, 20, 15, and 10 mA respectively, at a fixed voltage of 120 kVp.Standard and soft tissue algorithms were used to reconstruct the images.Three experienced doctors independendy evaluate the image quality and the efficiency of detecting PE of the images with various doses.The Pearson correlation analysis, two-tailed paired t test, ANOVA, and Kappa test were employed for the statistical analysis.Results The CT value difference between air within the trachea and the extracorpereal background region in 132 consecutive patients ranged from 20.00 to 55.00 HU, which had a positive correlation with weight[(64.99±11.86) kg], weight-height ratio [(38.71±6.13) kg/m], and BMI[(23.11±3.38) kg/m2](r=0.228,0.374,0.449 respectively; P <0.01).The image noise level with soft-tissue reconstruction algorithm[(16.55±9.08), (16.42±9.40) HU]was significantly lower than that of the image with standard reconstruction algorithm[(22.43±11.25),(21.99±11.67) HU](F=4.316, P < 0.05).The image noise level with soft-tissue reconstruction algorithm at 100 mA was similar to that of the images with standard reconstruction algorithm at 280 mA, and the signal-w-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the image of PE phantom was 23.05 and 20.52 respectively, without any impairment in detectability of embolus.The image noise level with soft-tissue reconstruction algorithm at 60 mA was similar to that of the image with standard reconstruction algorithm at 160 mA, while the SNR and CNR was 18.01 and 15.97 respectively, also with acceptable detectability of embolus.When the tube current was reduced below 30 mA, the image quality decreased significantly, with the SNR and CNR was lower than 12.36 and 10.95 respectively, and the detectability of embolus was degraded.The consistency of the image quality grading by 3 observers was excellent(K=0.807,0.712,0.904 ,respectively; P < 0.01).Conclusions The 100 mA may potentially be the ideal low dose tube current setting, with radiation dose only equal to 36% of 280 mA (standard dose).The 30 mA may possibly be a minimum radiation dose for detecting PE.The soft-tiasue reconstruction algorithm was favorable in preserving the SNR when the radiation dose was reduced.

Objective To investigate the detection rate and diagnostic value of multi-slice spiral CT scan in detecting fish bone impaction in the esophagus.Methods Experimental group: 30 fresh water fish bones from three variety classes were divided into three groups with length of(23.36±0.15), (28.51±0.07) and (30.89±0.10) mm, and diameter of (4.49±0.31), (1.78±0.09) and (0.49±0.07) mm.The fish bones were put into esophagus models in three different types including parallel, perpendicular and oblique.MSCT with axial scan combined with three dimensional reconstruction technique and plain X-ray film (CR and DR) were used to examine the model.The relations of the number and rate of fish bones were compared between MSCT and X-ray film.Clinical group: MSCT imaging were performed in 20 cases proved by esophageal endoscope or clinical operation, among which 11 cases received plain X-ray film (CR and DR), 15 cases received Barium-soaked cotton and 17 cases received endoscope.Paired Chi-square test was used to compare the differences of detection of fishbone by the different ways.Results In experimental group: All the 90 cases(100%) fish bones of three different species were clearly revealed on MSCT image; only 60 cases(66.7%) fish bones were revealed by plain X-ray film(CR and DR).The number and rate of fish bones detected by MSCT was higher than that of plain X-ray film (CR and DR) (X2=28.03, P < 0.01).In clinical group: 20 cases were made right diagnosis by MSCT, and the location and size of fish bone in the esophagus, the surrounding and complications of esophagus could be clearly demonstrated on MSCT image.Two cases detected by plain X-ray film(CR and DR) ;9 cases detected by Barium-soaked cotton;14 cases detected by endoscopy.The number and rate of fish bones detected by MSCT was higher than that of plain Xray film (CR and DR) (X2=7.11, P < 0.05) and Barium-soaked cotton (X2=4.17, P < 0.05).Conclusions The sensitivity and detection rate of fish bone with MSCT was high and could evaluate the surrounding and complications of the esophagus.MSCT could be used as the first examination of impacted fish bones in the esophagus.

Objective To characterize the association between the mean CT value on a scout view and the dependent mA selection method, and to evaluate the clinical value of a mA selection method based on scout view mean CT value in obtaining individualized scan protocol and consistent image quality for patient population on 64-row MSCT CT coronary angiography (CTCA).Methods One hundred patients (group A) underwent CCTA consecutively using standard protocol with a fixed mA.The mean CT value of a fixed ROI (region of interest) from the scout AP view and the CTCA image noise (standard deviation on the root of ascending aorta) were measured.The correlation between CT values and noise was studied establish a formula and a list to determine the required mA for obtaining a consistent CTCA image noise based on the measured SV CT value.Another 100 patients (group B) were scanned using the same parameters as group A except the mA and the CT value was also measured.The mA was determined by the list established previously.The CTCA image quality (IQ) as well as the image noise (IN) and the effective dose (ED) from the two groups were statistically analyzed using t-test.The CT findings for the 32 patients in the group B were also compared with the selective coronary angiography (SCA) results.The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of CCTA for detection of significant stenosis were obtained.Results The formula between the required mA and the CT value was : XmA=FmA×[(K1×CTscout + C1)/INa]2.The CCTA images in B group had statistically higher IN (27.66±2.57,22.22±4.17,t=11.33, P=0.000), but no statistical difference between IQ scores for the two groups (3.29±0.66,3.37±0.67,t=0.009, P=0.990), and ED[(8.72±2.51) versus (12.53±0.90) mSv]was 30% lower for the B group (P<0.01).For the 32 patients in the B group who had SCA, the CCTA sensitivity, specificity, positive predictive value, negative predictive value, and stenosis detection accuracy were 94.92% (56/59), 92.13% (82/89) ,88.89% (56/63) ,96.47% (82/85) and 93.24% (138/148) wspectively for stenosis greater than 50%.Conclusion The mA selection method based on the SV CT value for CCTA in 64-row MSCT provides individualized protocol to obtain consistent image quality and to optimize dose delivery to patients.