Objective To evaluate the diagnostic value of multi-slice thrce-dimensional computed tomographic angiography(MS-CTA) with volume rendering(VR) for Moyamoya disease.Methods MS-CTA of 25 patients with Moyamoya disease verified by DSA were restrospectively analyzed.Source images were got by GE Lightspeed pro scanner.VR was adopted to reconstruct 3D images in all cases.Results Of 25 CT precontrast,13,12 cases showed infarction and hemorrhage respectively,while 11 cases had dialated vessels in thalamus-basal ganglia region on CT.Accuracy of stenosis or occlusion of the bifurcation of ICA, proximal portion of the ACA or MCA was 88.0% (22/25) by MS-CTA.MS-CTA overestimated the degree of stenosis,MS-CTA misdiagnosed 3 cases(12.0%)with stenosis to occlusion.MS-CTA showed fewer small Moyamoya vessels than DSA.MS-CTA only demonstrated 6 cases(25.0%)with collateral vessels.Conclusion CT is still the conventional method for detecting secondary lesions to Moyamoya disease.CT and MS-CTA can accurately diagnose Moyamoya disease.

Objective To discuss the application of endoscopic techniques in the treatment of calculus of intrahepatic or extrahepatic duct. Methods Laparoscopy in conjunction with duodenoscopy or cholangioscopy was adopted in 96 cases of calculus of intrahepatic or extrahepatic duct, including 72 cases of cholecystolithiasis complicated by choledocholithiasis, 16 cases of simple choledocholithiasis and 8 cases of left intrahepatic duct calculus complicated by choledocholithiasis. The surgical procedures included laparoscopic cholecystectomy (LC) combined with EST (37 cases), LC combined with cholangioscopic exploration (54 cases), and laparoscopic left hepatic lobectomy combined with cholangioscopic exploration (5 cases). Results Postoperative re-examination revealed no residual calculus in 93 out of 96 patients. Small amounts of biliary leakage occurred in 4 patients and healed spontaneously within a mean time of 10 days. No other severe complications took place. A conversion to open surgery was required in 3 patients, 2 of which were high bile duct stricture and 1 of which were severe portal adhesion. Conclusions Endoscopy in the treatment of calculus of intrahepatic or extrahepatic duct is feasible. Proper application of multiple endoscopic techniques is a safe, effective and minimally invasive means for the treatment of cholelithiasis.

Objective To evaluate the clinical value of 320-detector CT in interventional treatment of bronchial artery hemoptysis. Methods CTA and DSA images of 30 patients with bronchial artery hemoptysis were retrospectively analyzed.Spatial anatomical characters of the bronchial arteries,such as the type of branches,origin and opening positions of the bronchial arteries were observed and recorded.Results In 30 patients,6 bronchial arteries distribution patterns were found,and the most common type was R1 L1 (43.3%).83 bronchial arteries were identified using CTA,including 38 on the right and 45 on the left.The right bronchial arteries mainly originated from the intercostal artery (52.6%),while the left bronchial arteries mainly from the descending aorta and aortic arch (82.2%).The opening positions of right and left bronchial arteries were mainly located at the right wall of the descending aorta (78.9%),and anterior wall of the descending aorta (62.2%),respectively.When the cacarina of trachea was used as the reference position,the left and right bronchial arteries were mainly located in the range of above 2 cm to below 1 cm from tracheal bifurcation, accounting for 80% and 89.5%,respectively.Compared with DSA,the sensitivity and specificity of CTA were 97.5% and 100%, respectively.Conclusion 320-detector CT can be used to clearly display the distribution patterns,origin and opening positions of bronchial arteries,and especially to find bronchial arteries with ectopic origin.It is possible to apply 320-detector CT in preoperative routine examination and postoperative evaluation of massive hemoptysis.

Objective To compare the difference of entrance dose between CR and amorphous silocon DR system in chest imaging, and to discuss their optimum exposure dose. Methods For CR and DR, different entrance dose was measured by dosimeter in chest phantom. The value of IQFinv was analyzed by CDRAD2. 0 software. Image quality difference between CR and DR was assessed by group t-test. The relationship between image quality and entrance dose was tested by using Pearson correlation analysis. The best IQFinv values in CR and DR system were achieved via ROC curve analysis, and the exposure dose was then calculated. Results There were direct correlation values between entrance dose and the value of IQFinv in CR and DR system, respectively( r =0. 893 ,0. 848 ,P < 0. 01 ) . The linear regression equation for DR was IQFinv =0. 0050 +3. 359, and for CR was IQFinv =0. 005D + I. 651 , where D was entrance dose. The difference of IQFinv value between CR and DR was significant(t = 5. 455 ,P < 0. 05). The best IQFinv value of the two groups from ROC analysis was 3.55. Conclusions With the entrance dose increased, the detection ability of contrast-detail was elevated in the two digital radiography systems. With equal entrance dose, the detection ability of DR in contrast-detail was superior to CR. With equal image quality, DR obviously decreased the radiation dose to the patients.

Objective To discuss the effect of the bedside shielding protection on the first and second operators against position radiation in percutaneous coronary intervention.Methods The surface entrance dosage rate for the first and second operators at 125 cm height with and without radiation protection shielding (provided separately) were measured.The t-test was used for statistical analysis of arithmetic mean values of dosage rates.And the effect of bedside shielding protection was calculated.Results The position radiation dosage rate at which the first operator exposed was significantly higher than that for the second in the case of no bedside protection (t =97.1-2 263.0,P ＜ 0.05),whereas the dosage rate at which the first operator (except for the left foot position) exposed was significantly lower than that for the second in the case of no bedside protection (t =-80.9-275.1,P ＜ 0.05).The shielding effect of bedside protection on the first and second operators was in the range of 92.26％-99.36％ and 27.83％-97.90％,respectively.Conclusions The bedside protection may effectively reduce position radiation dose to patients and the use of bedside protection changed the trends in the dose distribution in operators' standing region.Attention should be focused on the radiation protection of the second operators in daily work by making full use of bedside protection.

Objective To evaluate the feasibility of optimized scan protocol in whole-brain perfusion imaging with 320-MDCT scanner.Methods Twenty healthy volunteers were randomly divided into control group (13 patients) and test group (7 patients).The standard perfusion scan protocol (collecting 19 volumes)was applied in control group.The optimized perfusion CT scan protocol(collecting ll volumes)formulated by reducing scanning phases reasonably and changing the collection intervals was applied in test group.The regions of interest(ROI) with area of(20 ± 2)mm2 were located in the bilateral frontal white matter,parietal white matter,centrum semiovate,basal ganglia,occipital lobe and cerebellum.Bilateral perfusion values from ROI were measured,including cerebral blood volume(CBV),mean transit time (TTP),cerebral blood flow (CBF),mean transit time (MTT) and delay time (DT).Results Dose length product (DLP)and effective dose (ED)in optimized protocol were decreased 42.02％ as compared to control group.Every relative perfusion value of both sides from both groups were not statistically significant (P ＞ 0.05).Every relative perfusion parameters from individual territory in both groups showed no significant differences (P ＞ 0.05).Conclusions Using the optimized scan protocol,we could obtain the same whole-brain perfusion values could be obtained with the default standard protocol and less radiation dose.

According to the characteristics of our hospital,we establish a PACS/RIS system by adopting individual adaptive compartments and design,and study the net connection methods,key technique as well as the application value of the PACS/RIS system.As a result,PACS/RIS system enables the interchange of images among different models,brings about the centralized storage,the transference and process of remote images,and accomplishes the digitalization of registration and reporting.It optimizes the work flow for the radiography department.

Objective To study the effects of two different methods of high-pressure injections on imaging quality of synchronous left axillary artery and vein by using volume CT.Methods Forty seven patients who underwent left axillary vein and artery CTA examination study were analyzed retrospectively according to the contrast agent injection scheme and was divided into two groups A and B.Group A of 25 patients used protocol A,adopted clinical routine delay scanning method,via right elbow vein inject contrast medium.Group B of 22 patients used protocol B,adopted artery delayed imaging combined with vein direct imaging method,via right elbow vein,left radial vein inject contrast agent,respectively.Both values of CT and contrast to noise ratio (CNR) of two groups were compared,objective image quality was compared by two blinded readers.Mann Whiteny U test was used.Results The median of CT values for left axillary artery in group A was 151.9 HU.The median of CNR values for left axillary artery in group A was 7.4.The median of CT values for left axillary vein in group A was 116.0 HU.The median of CNR values for left axillary vein in group A was 3.83.The median of CT values for left axillary artery in group B was 348.8 HU.The median of CNR values for left axillary artery in group B was 25.3.The median of CT values for left axillary vein in group B was 497.0 HU.The median of CNR values for left axillary vein in group B was 35.4.Both values of CT and CNR in two groups showed significant difference (Z=-5.735,-5.799,-5.863 and-5.863,P＜0.01).All of the median scores in group B were greater than in group A(P＜0.01).Conclusion The enhancement effect of protocol B in the left axillary arteriovenous synchronous imaging is significantly higher than those of protocol A,and demonstrates clear image quality and clearer anatomic relationship.

Objective To investigate the radiation dose delivered to the patients with dense breasts and the influence of photographic conditions on image quality in full field digital mammography (FFDM).Methods (1) Clinical test:we analyzed the compression thickness of breasts,Target-filter(T-F),voltage current (kV),tube current (mAs),average glandular dose (AGD) and entrance surface dose (ESE) of 100 patients (a total of 370 images,277 images of Molybdenum-Rhodium(Mo-Rh)and 93 images of Wolfram-Rhodium (W-Rh)) who underwent examinations in mode of automatic exposure by FFDM with dense breasts.(2) Phantom experiments:placed the Aluminium plate on different thickness of polymethyl methacrylate (PMMA) plates to simulate the dense breasts.68 mm phantom was used to simulate photographic condition of W-Rh and 58 mm to Mo-Rh.The two groups of dense phantom were exposed automatically and manually.The parameters were recorded for each exposure including the compression thickness of breasts,T-F,kV,mAs,AGD,ESE,the calculation of the ratio between ESE and AGD (ESE/AGD).The image quality figure inverse (IQFInv) was obtained by software.To the clinical test,used multiple factors of variance to analyze the influence of compression thickness and mAs on AGD and ESE,Pearson correlation and regression to analyze the influence of compression thickness on ESE/AGD.To the phantom experiments,used Pearson correlation to analyze the influence of kV and mAs on AGD,ESE and ESE/AGD,single factor of variance to analyze the influence of kV and mAs on IQFInv.Results (1) Clinical test:to Mo-Rh and W-Rh,with the increase of compression thickness,ESE/AGD was increased significantly.Compression thickness had linear relationship with ESE/AGD.Pearson correlation coefficients of W-Rh and Mo-Rh were 0.956 and 0.980,respectively(P＜0.01).The effects of compression thickness and mAs on AGD and ESE were statistically significant (P＜0.05) in the two groups.(2)Phantom experiments:adjusted exposure parameters to the two dense phantoms of W-Rh and Mo-Rh.With the increase of mAs and kV,IQFInv was increased in W-Rh and Mo-Rh.Different mAs and kV were statistically significant (P＜0.05) on IQFInv,mAs and kV had positive correlation with ESE and AGD (P＜0.05),mAs and kV had different correlation with ESE/AGD in the two dense phantoms.Conclusions In mode of automatic exposure by FFDM,choosing W-Rh can achieve relatively high image quality and lower radiation dose.According to the results of phantom experiments,adjusting kV and mAs properly in manual exposure can reduce AGD and ESE effectively and ensure the quality of the image.

Objective To evaluate the reliability of CT perfusion parameter values of the normal hepatic segments and neoplasms, obtained with deconvolution (DC) and maximum slope (MS) algorithms. Methods Perfusion parameter values of 111 ROIs in 62 normal hepatic segments and 49 neoplasms derived from 62 CT perfusion studies performed with 320 multi-slice CT, were retrospectively analyzed by two experienced radiologists. BF,BV and PI according to DC and MS algorithms were compared with t paired test, Pearson correlation and Bland-Altman agreement analysis. Interobserver agreement for all perfusion parameters was calculated using intraclass correlation coefficients (ICC). Results Interobserver agreement measured with ICC was very good for all perfusion parameters (≥0.95). BFdc and BVdc exceeded the BFms and BVms in normal hepatic segments and neoplasms (P<0.05); PIdc significantly exceeded the PIms in normal hepatic segments(P<0.05) ,while no difference were found in hepatic neoplasms(P>0.05). Both pairs of perfusion measurements significantly correlated with each other(r>0.9, P<0.01),but the agreement of BF, BV and PI according to DC and MS algorithms was not good. Conclusions CT perfusion values such as BF,BV and PI obtained by DC and MS algorithms correlated significantly with each other, but with poor agreement.