Objective To explore the characteristics and applied value of diffusion-weighted MR imaging of kidney in healthy people.Methods Using Philips Gyroscan Intera 1.5T MR System,DWI of kidney was performed in 40 healthy adult volunteers,the ADCs of renal cortex and medulla were measured.Results The cortex and medulla of the normal kidney could be clearly showed by DWI.The ADCs of the cortex medulla and average were 3.08?0.52,2.74?0.68 and 2.91?0.58;2.79?0.51,2.53?0.65 and 2.63?0.62;2.64?0.43,2.32?0.47 and 2.48?0.44 when the b values were 300,500 and 800 s/mm2,respectively.The ADC was higher in the cortex than that in the medulla.Conclusion DWI can be used in kidney,it may be helpful for the diagnosis of renal diseases.

Patellar instability is a common cause of knee pain and a common disease of patellofemoral joint.It is one of the important etiological factors of chondromalacia patella or patellofemoral joint osteoarthritis.This paper investigates the pathological mechanism,sympton,physical examination and photographic of patellar instability.And the results showed that correct diagnosis lead to reasonable treatment.The emphasis of therapy is to restore the balance of soft tissue around palella.Combined orthopedic treatment is commonly used according to different age,different instability degrees,and pathological factors of different patients.

The impeller profile, which is one of the most important factors, determines the creation of shear stress which leads to blood hemolysis in the internal flow of centrifugal blood pump. The investigation of the internal flow field in centrifugal blood pump and the estimation of the hemolysis within different impeller profiles will provide information to improve the performance of centrifugal blood pump. The SST kappa-omega with low Reynolds correction was used in our laboratory to study the internal flow fields for four kinds of impellers of centrifugal blood pump. The flow fields included distributions of pressure field, velocity field and shear stress field. In addition, a fast numerical hemolysis approximation was adopted to calculate the normalized index of hemolysis (NIH). The results indicated that the pressure field distribution in all kinds of blood pump were reasonable, but for the log spiral impeller pump, the vortex and backflow were much lower than those of the other pumps, and the high shear stress zone was just about 0.004%, and the NIH was 0.0089.
Assisted Circulation ; Heart-Assist Devices ; Hemolysis ; Humans ; Models, Theoretical ; Stress, Mechanical

Objective To analyze CT morphologic features and pathologic changes of pulmonary sclerosing pneumocytoma (PSP) and to improve preoperative diagnostic accuracy of PSP.Methods The clinical and CT data of 12 cases with PSP (with total 13 lesions)confirmed by surgery and pathology were collected and analyzed retrospectively.All cases performed CT plain scan,9 cases had contrast CT scan.Results 1 1 cases had isolated lesions,and 1 case multiple lesions.The long-axis diameter ranged from 1.10 cm to 8.03 cm, with an average of (3.53±0.78)cm.Of 13 lesions,3 located in left lung (23.1%,1 in the upper lobes,2 in lower lobe),and 10 in right lung (76.9%,2 in upper lobe,2 in the middle lobe and 6 in lower lobe);8 lesions located in the lower lobe (61.5%),and 5 in upper and middle lobe (38.5%).There were center type of 4 lesions (30.8%),and peripheral type of 9 lesions (69.2%);The shapes of 8 lesions wereovoid or similar round (61.5%),irregular type of 1 case (7.7%),shallow lobe of 4 cases (30.8%);Smooth edge of 10 cases (76.9%), burr edge in 3 cases (23.1%).With contrast CT scan,7 cases (53.8%)had vascular welt sign,6 cases (46.2%)had air crescent sign,6 cases (46.2%)had halo sign,and 6 cases (46.2%)had tail sign.3 lesions (23.1%)had scattered spot calcification,and the other lesions had uniform density.The CT value ranged from 28 HU to 47 HU,with the average of 35 HU;Of 9 cases (with 10 lesions)with contrast CT scan,2 lesions had mild enhancement,5 cases had obvious enhancement,and 3 case had non-uniform enhancement.Enhanced CT value was 60-1 10 HU,with the average of 77.2 HU,and with the maximum of 75 HU.Conclusion If the pulmonary nodules or masses in middle-aged females had single round or ovoid shape,with about 3 cm diameters,soft-tissue density,smooth edge,and with obvious enhancement after contrast CT scan,and accompanied by vascular welt sign,air crescent sign,halo sign,or tail sign, the diagnosis of PSP should be considered.

Objective To study feasibility in extraction of calcific sign within pulmonary nodules with pattern classification.Meth-ods 49 cases with pulmonary nodules (benign in 16 and malignant in 33)confirmed by pathology or clinical follow-up were included in this study and all cases underwent chest CT examinations.CT images were interpreted double-blind by two associate chief radiolo-gists to draw a conclusion that there were any calcification within pulmonary nodules.Meanwhile,the calcifications in the regions of interest(ROI)on CT images were estimated with extraction of the sign of gray value,geometric and lung markings in ROI,and based on pattern classification algorithm at supporting vector machine(SVM).Results According to the results assessed by senior radiologists for classification within pulmonary nodules,the area under ROC curve was 0.95 which was extracted by automatic pat-tern classification algorithm,the extraction performance was stable(k=1),and was goodness fit with visual observation by doctors (k=0.939).Conclusion The ability of automatic pattern classification in detecting calcification within pulmonary nodules is about the same as that of visual assessment by senior doctors.

Objective To evaluate the clinical diagnostic value of magnetic resonance cholangiopancreatography ( MRCP ).Methods MPCP data of 42 cases with pancreatic and bile duct lesion proved by operation and pathology were analyzed retrospectively.MRCP was performed using single-shot-radio SE sequence (SSH/RAD). Of all cases included bile duct lithiasis in 19 , inflammation in 3,congenital cyst in 6 , carcinoma in 12,jaundice caused by diverticulitis of duodenum in 1 and Mirizzi syndrome in 1 .Results MRCP was succeeded at one time in all cases . On MRCP , the visual rate of intrinsic and extrinsic hepatic bile duct was 100% and that of common pancreas duct was 80.58%.The localized and qualitative diagnosis of lesions were up to 100%,88.2% respectively.Conclusion SSH/MRCP/RAD plays an important role in diagnosis of the pancreatic and bile duct lesion in clinical practice.

Objective To analyse the CT features of hepatic abscess in different stages of pathology so that to improve the accuracy of CT diagnosis.Methods The plain CT and triphase contrast-enhanced CT findings of hepatic abscesses in 50 cases proved by surgery or other clinical methods were retrospectively analysed and compared with CT findings of hepatic carcinoma,hepatic metastases and hepatic hemangiomas.Results CT features of hepatic abscesses were divided into three types according to different stages of pathology.Early pyogenic hepatic abscess(10 cases)had two types:small cavitation(9 cases)and mass(1 case).Typical pyogenic hepatic abscess(38 cases)and granulomatous hepatic abscess(2 cases).Conclusion CT findings of liver abscesses are different in different stage of pathologic changes,triphase contrast-enhanced CT is specific in diagnosing hepatic abscess.

Objective To explore CT and MR manifestations and its diagnostic value of liver cystic lesions.Methods The clinical and imaging data of 78 cases with liver cystic lesions were collected,including 21 cases of inflammatory cystic lesions,30 cases of tumor cystic degeneration and 27 cass of congenital growth cysts.Results The detected rate of liver cystic lesions with CT and MRI was all 100%.For inflammatory cystic lesions,tumor cystic degeneration and growth cyst,CT diagnostic accurate rate was 76%,90% and 93%,respectively,and MR was 83%,93% and 100% respectively.CT and MR manifestations:Of all inflammatory cystic lesions,hepatic abscess and liver echinococcosis cyst appeared as cystic occupying lesion,the cysts were of tension,low-density band on CT or water-like signal intensity on MR around the lesions in hepatic abscesses.Liver echinococcosis cysts were of big cyst with small cyst sign and enhanced moderately in cystic wall post contrast-enhanced scan.The metastasis cystic tumors showed single or multiple cystic lesions and mild or moderate circular enhancement.The primary liver tumor's cystc degenerative lesions showed cyst-solid lesions on CT and MR,and were of enhanced manifestations of the primary tumors.Growth cysts were single or multiple low-density or water-like signal intensity,generally there was not enhanced.Conclusion CT and MR have great diagnostic value for the location and nature of cystic lesions.

Objective To improve recognition and diagnosis of primary non-obstructive megaureter.Methods The authors analyzed the X-ray findings of intravenous urography and B-ultrasonographic manifestations of 28 cases with primary non-obstructive megaureter proved by varied examinations and operations.Results The X-ray and B-ultrasonographic manifestations as follows:in the terminal ureter,there was a short segment,less than 3 cm in length,with normal caliber but adynamic to micturition and the ureter proximal to the adynamic segment was secondarily dilated remarkably.The terminal end of the dilated ureter appeared as drumstick shaped,spindle-shaped,snakehead shaped or rattail shaped.On right time fluoroscopy and B-ultrasonographic observation,a decrease of peristalsis frequency,increase of peristalsis range,interrupted downward convey of peristalsis wave could be noted.Conclusion The contrast urography is the main method,B-ultrasonography and cyctocopy are helpful for the diagnosis of primary non-obstructive megaureter.

Objective To study the clinical and X-ray manifestations of primary non-Hodgkin's lymphoma(PNHL)of bone so that to suppy the valuable informations for clinical diagnosis and treatment of this disease.Methods 14 cases with PNHL of bone confirmed by clinic and pathology were analyzed retrospectively.There were 9 male and 5 femal,age ranged from 20 to 60 years with average of 35 years,and average history of disease was 11 months in all cases.Results Of all cases single bone involved in 11 cases,multiple bone involved in 3 cases,most of them the flat bone and the distal end of long bone were involved.The appearances of the lesion on X-ray were bony destruction with slight sclerosis at the margin of destructive area,there were periosteal reaction,soft tissue masses and destruction of joint manifestations,PNHL of bone can be classified as four typers:osteolytic(n=8),sclerotic(n=2),mixed(n=3)and cystic(n=1)lesions by the form and feature of bone destruction.Conclusion PNHL of bone has characteristic X-ray manifestations comparatively.The correct diagnostic rate can be improved if we concern about clinical data.