Objective To study the value of CT angiography(CTA) and three dimensional contrast enhanced magnetic resonance angiography(3D CE-MRA) in the diagnosis of arteriosclerotic occlusive disease (ASO) of lower limb and evaluate arterial stenosis. Methods Thirty-eight patients clinically suspected ASO were studied with CTA and3D CE-MRA,twenty-two patients underwent DSA at the same time. The degree of seriousness of the stenosis shown by various imaging techniques were analyzed respectively. Results Using the DSA images as the standard reference, the sensitivity and specificity of CTA were 97.3% ,99. 1%, and MRA both were 100.0% in detecting the segments occluded. With regard the detection of segments that had more than moderate stenosis ,the sensitivity and specificity of CT were 99.3% ,97.6% ,and MRA were 97.9% ,96.4%. The degree of seriousness of the stenosis shown by MRA was overestimated than CTA on the segments that had more than moderate stenosis(x2 =5.80,P ＜0. 05). Conclusion CTA and 3D CE-MRA were reliable method in diagnosis of ASO.

Objective To evaluate the advantage of single -source spectrum CT in differentiating of calcifi-cation and tophus.Methods 146 cases of clinical suspected patients with gout pain were scaned by single -source spectrum CT,observed the adjacent to the bone and joint hyperplasia and showing characteristics of gout stone,coun-ted quantity,size and position of the sedimentary tophus.Diagnosed by American rheumatism association standard as the gold standard,computed the sensitivity,specific degrees and accuracy of showing tophus of single -source spec-trum CT and conventional CT,and evaluated the advantage of differentiating adjacent to the bone and joint hyperplasia and gout stone of single -source spectrum CT.Results Diagnosis of gout in 105 cases.Scaned 349 joints,positive in 341 of them,The first plantar toe joint involvement was obvious[118,34.60%(118/341)];The result showed that the sensitivities of the tophus,specific and accurate rate of the conventional CT were 63.80%(67 /105),65.85%(27 /41),64.38%(94 /146),which of single -source spectrum CT were 96.19%(101 /105),87.80%(36 /41), 93.84%(137/146),the differences of sensitivity,specificity and accuracy between the two methods were statistical significance(χ2 =34.42,555,38.34,all P <0.05).Conclusion Single -source spectrum CT in gout stone adjacent to the bone and joint has higher sensitivity and accuracy,specific degree,it is higher than conventional CT and provide a new noninvasive imaging technique for the identification of the peripheral bone and joint of the bone.

Objective To investigate MRI susceptibility weighted imaging( SWI) sequence on diagnostic value and clinical significance of spinal cord injury.Methods 52 cases admitted from Jan.2012 to Dec.2013 were collected.They underwent routine MRI sequence and SWI scanning.The conventional sequences and SWI for displaying hemorrhage were analyzed and compared.The patients were followed.Results The display rate of SWI scan for edema, contusion, and bleeding was significantly higher than that of the conventional group.The difference had statistical significance(P<0.05).SWI scanning imaging time was shorter than that of the conven-tional group.The difference had statistical significance(P<0.05).The type of spinal cord injury was mostly e-dema, accounting for 38.5%, significantly more than hemorrhage, necrosis and thickening.Conclusion SWI is more sensitive and clear in displaying bleeding caused by spinal cord injury compared to the conventional MRI se-quence, which is an important inspection method in spinal cord injury.

Objective To discuss the application value of the multi-slice spiral CT in diagnosing breast cancer. Methods The images of scanning, enhancing and reconstruction were analyzed in 29 cases of breast cancer proved by clinical pathology. Results All the 29 cases were the type of mass. 25 cases of them located in outer and upper quadrant of the galactophore. The shapes of the tumor in 22 cases were irregular , burrs can be seen in 9 cases, the skin in 4 cases changed, the nipples in 2 cases sunk, the tissue around the tumor was invaded in 5 cases; The CT value of the tumor rised greatly after enhancement, the ranges of value was from 18 to 83 HU. Axilla lumph nodes were detected in 16 cases, we can find the lumph node in mediastinum and lung metastasis in 3 cases; The tumor and the tissue around it can be shown well in multi-orientations through image reconstruction. Conclusion The multi-slice spiral CT has the evident application value in qualitative diagnosing breast cancer.

Objective To study the effects on tissue CT number caused by scan protocols.Methods The phantom was repeatedly scanned in different protocols by changing only one of parameters,such as X-ray tube voltage,mAs and recon kernel,while other parameters were ketp unchanged.The CT number of different materials in phantom were measured and analyzed.Results The CT numbers of tissues changed remarkably with the tube voltage and had different relativity for different tissues.The CT numbers had positive correlation with kV for such maierials as polyethyle,lexan,perspex,but for teflon the correlation was negative.The mAs and recon kernel had no effects on CT number.Conclusions The CT number of tissue changes with scanning X-ray tube voltage,so the setting of scan parameters should be taken into account in image diagnosis and radiotherapy.

Objective To investigate the application values of B-mode ultrasonography , IVU and spiral CT urography (CTU) in duplication of kidney and ureter. Methods Data of the results from B-mode ultrasonography , IVU and spiral CTU on 85 cases with duplication of renal pelvis and ureter were retrospectively analyzed. Results The diagnostic accordance rates of B-mode ultrasonography , IVU and spiral CTU for duplication of kidney and ureter were 44.7%, 60.0% and 100%, respectively. CTU examination and image post-processing could clearly display the locations and degrees of dilatation or obstruction in duplication of kidney and ureter, and could also display the ectopic location and assess renal function. Conclusion The diagnostic accuracy rate of CTU examination and image post-processing for duplication of kidney and ureter is higher than those of B-mode ultrasonography and IVU.