The CT imaging diagnosis and surgical treatment of mixed epithelial and stromal tumors of the kidney / 中华泌尿外科杂志

Objective:To investigate the CT features and surgical treatment of mixed epithelial and stromal tumor of the kidney (MESTK).Methods:From April 2015 to August 2018, 13 patients with MESTK confirmed by pathology at the First Affiliated Hospital, College of Medicine, Zhejiang University, were enrolled in this study and their clinical data were analyzed retrospectively. These patients included 3 males and 10 females, with age ranging from 22 to 80 years old and the median age of 37 years old. Two patients complained of lumbar discomfort with urinary urgency and another 2 patients presented with hematuria. Nine patients were asymptomatic and their renal lesions were detected by abdominal ultrasonography for physical examination or other reasons. There were 2 cases had a history of polycystic kidney disease, 1 patient took contraceptive for 2 years, and 3 cases took antihypertensive agents for 5-10 years. The other patients denied any administration of hormone or other medicine for long time. The urine routine test was normal for these patients except for 2 patients did not take this test before operation. The creatinine value ranged from 45 to 486 μmol/L, with the median value of 67 μmol/L. The scope of glomerular filtration rate (GFR) was 6.98 to 132.28 ml/min, with the median value of 109.28 ml/min. The preoperative computer tomography (CT) showed single neoplasm in 11 patients and no obvious neoplasm was found in 2 patients who had polycystic kidney disease. Moreover, these lesions presented cystic neoplasm for 8 cases, cystic-solid neoplasm for 2 cases and solid neoplasm for 3 cases. Long diameter was measured about 2.5 to 7.5 cm, with the median of 5 cm, and calcification was found in 4 cases. These tumors manifested mild to moderate enhancement and delayed-enhancement for tumor parenchyma and intracapsular septum. The CT attenuation value was from 20 to 55 Hounsfield unit (HU). Base on the R. E.N.A.L. score system, these renal lesions got 4 to 10 points, with the median value of 7 points. Before operation, just 1 case was diagnosed as angiomyolipoma and 2 cases were diagnosed as polycystic kidney disease. No definitive diagnosis was made for the other 10 cases by CT imaging. In addition, the tumor staging based on preoperative imaging was made at T1a for 8 cases and T1b for 3 cases. Among these cases, 2 patients with polycystic kidney disease underwent open radical nephrectomy due to recurrent hematuria and uremia. One patient underwent laparoscopic radical nephrectomy due to perirenal fat adhesion. Partial nephrectomy was performed in remaining 10 patients by open surgery for 6 patients, robotic surgery for 3 patients and laparoscopic surgery for 1 patient. These renal tumors and 0.5-1.0 cm surrounding normal renal parenchyma were removed during operation.Results:In this study, 8 patients had blood loss of 30 to 100 ml during open operation, and 5 patients had blood loss of 20 to 100 ml during laparoscopic or robotic surgery. The warm ischemic time during partial nephrectomy was around 17 to 40 min, with the median value of 20 min. All of 13 cases were diagnosed as MESTK by postoperative pathology and the surgical margin was negative. There were no serious complications or special treatment after operation. The follow-up time ranged from 12 to 41 months, with the median time of 21 months. Obvious signs of tumor recurrence or metastasis were not detected in 13 cases during follow-up.Conclusions:CT images of MESTK mostly presented cystic or cystic-solid lesions, and solid lesions were relatively rare. This disease always showed mild to moderate enhancement and delayed enhancement of septal or tumor parenchyma. If there is coarse calcification in the lesions, it is more likely to be diagnosed as MESTK. Partial nephrectomy is preferred and radical nephrectomy should be considered when perirenal fat adhesion is suggested by the preoperative CT images.

Clinical value of radiomics based on CT examination in preoperative differential diagnosis of pancreatic serous cystadenoma and mucinous cystadenoma / 中华消化外科杂志

Objective:To investigate the clinical value of radiomics based on computed tomography (CT) examination in preoperative differential diagnosis of pancreatic serous cystadenoma (SCA) and mucinous cystadenoma (MCA).Methods:The retrospective case-control study was conducted. The clinicopathological and imaging data of 154 patients with pancreatic cystic neoplasms who were admitted to the First Affiliated Hospital, Zhejiang University School of Medicine from January 2012 to December 2019 were collected. There were 24 males and 130 females, aged (50±13)years. Of the 154 patients, 99 cases were diagnosed as SCA and 55 cases were diagnosed as MCA. All the 154 patients underwent plain and enhanced CT scan of pancreas before operation. The clinical characteristics, radiology features and radiomics features of all patients were collected to construct the clinical characteristics model, radiology model, radiomics model and fused model. The receiver operating characteristic (ROC) curve of each model was drawn, and those constructed models were evaluated by area under the curve (AUC), accuracy, sensitivity, specificity, positive predictive value and negative predictive value. Based on the optimal model, the nomogram was constructed. Observation indicators: (1) establishment and validation of clinical characteristics model; (2) establishment and validation of radiology model; (3) establishment and validation of radiomics model; (4) establishment and validation of fused model; (5) nomogram of fused model. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the Mann-Whitney U test. Count data were described as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test or Fisher exact probability. Results:(1) Establishment and validation of clinical characteristics model: 3 clinical characteristics, including age, symptoms and preoperative serum CA19-9, were selected using multinomial logistic linear regression analysis to construct the clinical characteristics model. Result of the multinomial logistic linear regression analysis was expressed by formula ①: clinical characteristics model score=0.635-0.007×age+0.054×clinical symptoms+0.108×preoperative serum CA19-9. The ROC curve for the test dataset of clinical characteristics model was drawn. The AUC, accuracy, sensitivity, specificity, positive predictive value and negative predictive value of clinical characteristics model were 0.611(95% confidence interval as 0.488?0.734, P<0.05), 56.6%, 66.7%, 56.3%, 41.5%, 78.4% for the training dataset and 0.771(95% confidence interval as 0.624?0.919, P<0.05), 77.8%, 63.1%, 88.5%, 80.1%, 76.7% for the test dataset, respectively. (2) Establishment and validation of radiology model: 5 radiology characteristics, including tumor location, the number of tumors, tumor diameter of cross section, lobulated tumor and polycystic tumor (more than 6), were selected using multinomial logistic linear regression analysis to construct the radiology model. Result of the multinomial logistic linear regression analysis was expressed by formula ②: radiology model score=?0.034+0.300×tumor location+0.202×the number of tumors+0.014×tumor diameter of cross section?0.251×lobulated tumor?0.170×polycystic tumor (more than 6). The ROC curve for the test dataset of radiology model was drawn. The AUC, accuracy, sensitivity, specificity, positive predictive value and negative predictive value of radiology model were 0.862(95% confidence interval as 0.791?0.932, P<0.05), 78.8%, 81.8%, 77.5%, 62.8%, 90.2% for the training dataset and 0.853(95% confidence interval as 0.713?0.994), P<0.05), 88.9%, 89.4%, 88.5%, 85.0%, 92.0% for the test dataset, respectively. (3) Establishment and validation of radiomics model: 4 categories of a total 1 067 radiomics features were extracted from 154 patients with pancreatic cystic neoplasms, including 7 first-order histogram features, 53 texture features, 848 wavelet features and 159 local binary pattern features. A total of 896 stable radiomics features were retained to construct the model, based on the condition of intraclass correlation coefficient >0.9. After selected by variance threshold and correlation coefficient threshold, 350 radiomics features were retained. Fifty synthetic radiomics features were constructed based on the original features in order to obtain potential radiomics features, and the total number of radiomics features was 400. After analyzed by the five-fold recursive feature elimination, 22 radiomics features were screened out, including 13 wavelet features, 7 synthetic radiomics features and 2 local binary pattern features. The support vector machine algorithm was used to construct the radiomics model. The penalty coefficient 'C' and parameter 'γ' of the radiomics model were 35.938 and 0.077, respectively. The kernel function of the radiomics model was 'radial basis function kernel'. The ROC curve of radiomics model using 5-fold cross validation was drawn. The average AUC, accuracy, sensitivity, specificity, positive predictive value and negative predictive value of the radiomics model were 0.870 ( P<0.05), 83.1%, 81.8%, 83.8%, 73.8% and 89.2%, respectively. (4) Establishment and validation of fused model: the fused model was constructed after selecting the tumor location and lobulated tumor of radiology characteristics and radiomics score. Result of the multinomial logistic linear regression analysis was expressed by formula ③: fused model socre=?0.154+0.218×tumor location?0.223×lobulated tumor+0.621×radiomics score. The ROC curve for the test dataset of fused model was drawn. The AUC, accuracy, sensitivity, specificity, positive predictive value and negative predictive value of fused model were 0.893(95% confidence interval as 0.828?0.958, P<0.05), 83.7%, 81.8%, 84.5%, 71.1%, 90.9% for the training dataset and 0.966(95% confidence interval as 0.921?0.999, P<0.05), 91.1%, 84.2%, 96.2%, 94.1%, 89.3% for the test dataset, respectively. (5) Nomogram of fused model: the nomogram of fused model was illustrated with the Youden index of 0.416. Conclusion:The prediction model based on the radiomics signature and radiological features extracted from preoperative CT examination can make the differential diagnosis of pancreatic SCA from MCA.

Imaging manifestations of intra-abdominal aggressive fibromatosis and correlation with pathology / 实用放射学杂志

Objective To investigate the CT and MRI manifestations of intra-abdominal aggressive fibromatosis and correlation with pathology.Methods The CT and MRI manifestations of 26 cases with intra-abdominal aggressive fibromatosis confirmed by pathological examination were analyzed retrospectively.Results 26 cases showed single solid mass,13 cases showed well-circumscribed and round-like,9 cases wrapped around the common bile duct,intestine or ureter,4 cases were lobulated which had unclear margin with surrounding tissues in pelvic.All the lesions displayed isodensity or slightly low density non-enhanced CT appearance,heterogenous high intensity FS T2WI,some larger tumors showed mixed signal.CT/MRI enhanced scan showed gradual enhancement in 26 cases.Conclusion Intra-abdominal aggressive fibromatosis have some certain imaging features,MRI can offer the histo logical features of tumors and have some correlation with pathology.

Analysis of clinical prognosis and the correlation between bile duct injury after transcatheter arterial chemoembolization and the level of hepatic arterial embolization in patients with hepatocellular carcinoma / 中华肿瘤杂志

Objective@#To evaluate the correlation between bile duct injury after transcatheter arterial chemoembolization and the level of hepatic arterial embolization, and to analyze the clinical prognosis of hepatocellular carcinoma patients.@*Methods@#From January18, 2012 to December18, 2014, 21 patients underwent TACE for HCC were retrospectively reviewed, including patients′ clinical and pathological data. The clinical outcome and relevant factors for bile duct injury were analyzed.@*Results@#A total of 21 patients were identified with bile duct injury at our single institution. All patients received 48 TACE treatments, including proper hepatic artery (14), left hepatic artery (3), the right hepatic artery (10), left and right hepatic artery (9) and tumor artery branches (12). Thirty-five bile duct injury occurred in 21 patients: 7 cases was close to the tumor, 2 distant to the tumor, 7 at right liver, 2 left liver, 11 both lobes of liver and 6 hepatic hilar. After medical conservative treatment and biliary tract inside and outside drainage, liver function of 10 cases were improved. In four patients with hepatic bile duct stricture and biloma, the effect of drainage was not obvious, which subsequently caused biliary complications such as infection, gallbladder and common bile duct stones. Three patients with liver cirrhosis at decompensation stage developed complications, and one of them died of hepatic encephalopathy. Four patients experienced tumor recurrence during the follow-up period.@*Conclusions@#The location of bile duct injury after transcatheter arterial chemoembolization is quite consistent with the level of hepatic arterial embolization. There may be some blood vessels mainly involved in blood supply of biliary duct. Complete embolism of these vessels may lead to bile duct injuries. Biliary drainage is ineffective in patients with hilar bile duct stricture, and can lead to complications of biliary tract later on.

BOLD MRI in evaluation of renal oxygenation in primary nephrotic syndrome / 中国医学影像技术

Objective To evaluate the renal oxygenation in patients with primary nephrotic syndrome (PNS) using BOLD MRI.Methods Twenty patients with untreated first-onset PNS and 18 healthy control subjects underwent BOLD MRI.The R2* of renal cortex and medulla were measured.Blood and urine samples were obtained on the day of MRI,and the patients underwent renal biopsy after MRI.The renal tubulointerstitial damage scores (TIDS) were determined using Katafuchi criteria.All patients received corticosteroids within 7 days after MRI and were followed up for 12 months.The difference of R2* levels between the PNS patients and controls were compared,and the correlations between R2* values and TIDS,laboratory parameters (eGFR,etc.) were tested.Results R2* values of renal medulla in PNS patients significantly decreased compared that of the controls (t =-9.270,P＜0.001).R2* values of renal medulla in PNS patients were negatively correlated with eGFR (r=-0.462,P=0.040) and positively correlated with TIDS (r=0.809,P＜0.001).There was a slight tendency for higher R2* values of renal medulla in individuals with poor prognosis.Conclusion BOLD MRI is a noninvasive method for the detection of renal oxygenation changes,which can evaluate the renal function and tubulointerstitial impairment,as well as prediction of the prognosis for PNS patients.

Imaging findings and morphology classification of intraductal papillary mucinous neoplasm of the bile duct / 中华放射学杂志

Objective To investigate the CT and MRI features and morphology classification of intraductal papillary mucinous neoplasm of the bile duct (IPMN-B).Methods A total of 18 patients with IPMN-B proved by pathology were retrospectively analyzed.Out of 18 patients,16 patients underwent enhanced and non-enhanced CT,13 underwent contrast enhanced MR,and 11 out of 13 underwent both CT and MRI.IPMN-B was classified into 4 types:typical IPMN-B,cystic-forming IPMN-B,non-tumor IPMN-B and invasive IPMN-B,according to imaging findings and gross pathological findings.Results Typical IPMN-B (9 cases):tumors were distributed along the bile ducts,both upstream and downstream bile ducts were obviously dilated.Cystic-forming IPMN-B (5 cases):single or multiple tumors were found in aneurysmal dilatation of bile ducts.Non-tumor 1PMN-B (2 cases):no mass was found in the widely dilated bile ducts with smooth bile duct wall.Invasive IPMN-B (2 cases):tumors protruded into the dilated bile ducts causing jagged wall of bile duct,with accompanied abnormal density or signal intensity outside the bile ducts.Bile duct dilatations were shown in all 18 cases,and tumors were shown in 16 cases.In 2 cases no mass was displayed in widely dilated bile ducts.CT density of the tumor was lower than that of liver parenchyma,and higher than that of the bile and intraductal mucin.Signal intensity of the tumor was higher than that of stones,and lower than that of bile and intraductal mucin at MR T2WI.All tumors showed high intensity on DWI.Tumors showed mild to moderate enhancement after injection of contrast agent,CT density or signal intensity of the tumors were lower than that of the liver parenchyma during all three phases of contrast-enhanced CT or MRI.Conclusion IPMN-B has some specific CT and MR imaging features,which are helpful for the diagnosis and classification of IPMN-B.

The comparison among image qualities of CTA at different dose in both lower extremity artery / 中华放射医学与防护杂志

Objective To explore the differences among CT angiography(CTA) at different doses in both lower extremity arteries,and the relationship among volume rendering(VR) image quality,CT number and standard deviation(SD) value.Method CTA in lower extremity artery was performed in 90 patients.The participants were randomly divided into three groups,including a routine group (120 kV,150 mAs),120 kV and 80 mAs group,and 100 kV and 130 mAs group with 30 cases in each group.The images were processed with VR and classified into three degrees,the first class,the second class and the third class,and VR image quality levels of three groups were compared.The receiver operating characteristic curve(ROC) was used to analyze the correlation among VR image quality level,CT number and SD value.Results The percentage of VR image level at the first class was 93.3％ in the routine group,86.6％ in the 120 kV and 80 mAs group and 96.6％ in the 100 kV and 130 mAs group.According to the correlation analysis between the SD value and VR image quality of CTA in lower extremity artery,the area under curve in ROC analysis was 0.9078.According to the correlation analysis between the CT number and VR image quality of CTA in lower extremity artery,the area under curve in ROC analysis was 0.9116.Conclusions The low-dose CAT in lower extremity artery is feasible.Application of 100 kV and 130 mAs could ensure better image quality.

Imaging features of splenic littoral cell angioma / 中华放射学杂志

Objective To investigate the imaging features of splenic littoral cell angioma (LCA)and correlate with pathological findings.Methods Ten patients of LCA with pathologically confirmed diagnosis were included in this study.A retrospective review of clinical data and imaging findings on CT and MRI was performed,along with review of the literature.Results Splenic littory cell angiomas presented with multiple nodules of varying sizes with a predoninance of small ones.Nine of 10 patients had clinical symptoms of splenomegalia and hypersplenia.MR T2WI and DWI showed masses with high-signalintensity.The CT and MRI enhancing pattern of LCA was similar to splenic hemangioma.There were many mammiliform structures pointing inside in the wall of the vascular channels,a hallmark feature allowing its differentiation from splenic hemangioma pathologically.Conclusion The CT and MRI findings of LCA can show some of its characteristic signs,especially on DWI,which can assist to identify LCA in clinical practice.

Influence of oxymatrine on cell proliferation and VEGF expression in human gastric cancer cell line SGC-7901 / 中国癌症杂志

Background and purpose: Oxymatrine, which is the main effective component of Sopkora flavescens Ait, has anti-fibrosis and antiviral activities, and also has a good effect on leukopenia after either chemotherapy or radiotherapy. Recent studies showed that oxymatrine has the abilities of anti-invasion and killing tumor cells in some degree, and as a supplementary anticancer drug in chemical therapy. In this study, we investigated the antitumor mechanism of oxymatrine by observing cell proliferation and VEGF expression in human gastric cancer SGC-7901 cell line. Methods: Human gastric cancer SGC-7901 cells was cultured in vitro and treated with oxymatrine, then cell proliferation was examined by the method of MTT. Immunohistochemistry was applied to examine the protein expression of VEGE The transcriptions of VEGF mRNA were demonstrated by RT-PCR technique.Results: Low-dose (0.5 mg/mL) oxymatrine has a mild inhibitory effect on cellular proliferation of SGC-7901 cells (P>0.05). When concentration exceeded 1 mg/mL, oxymatrine significantly inhibited cellular proliferation in a time-and concentration-dependent manner, and down-regulated the mRNA and protein expression of VEGF (P<0.05).Conclusion: Within a certain drug concentration, oxymatrine can inhibit the proliferation of SGC-7901 cells and play a potential role in inhibiting angiogenesis by down-regulating the expression of VEGF.

Application of low-dose in 3D CT pulmonary angiography / 中华放射医学与防护杂志

Objective To explore the feasibility of low-dose multi-slice computed tomography(MSCT) scan on pulmonary artery three-dimensional angiography, and the relationship between pulmonary VR image quality and the SD value of plain scan. Methods Pulmonary artery CT examination was performed in 87 patients. 63 volunteers were administered with low dose as a low-dose group, and the other 24 were scanned with conventional dose as a routine group. Both plain scans were use conventional dose of pulmonary scan with 150 mAs, and the low-dose pulmonary enhanced scans were used with 60 mAs. The images were post-processed with volume rendering(VR) and classified into three grades A, B and C, and VR image quality levels of both groups compared. The receiver operating characteristic curve( ROC) was used to analyze the relationship between VR image quality level and SD value of plain scan image SD value. Results The VR image level of A-class was 100% in the conventional dose group, and 85. 7% was in the low dose group . According to the correlation analysis between the standard deviation(SD) value of plain scan image and pulmonary artery VR image quality, the area under curve in receiver-operated characteristic analysis was 0. 906. Conclusions The low-dose scan of pulmonary artery three-dimensional angiography is feasible. Using 60 mAs low-dose in pulmonary artery enhanced scan could ensure better image quality. With the SD value of the plain scan decreased, the pulmonary artery VR image quality is improved.

Feasibility study of low-dose scan in 64-slice spiral CT abdominal angiography / 中华放射医学与防护杂志

Objective To explore the feasibility and reasonable of low-dose scan on abdominal angiography in 64-slice spiral helical CT. Methods Phantom test: at 120 KV and from 200 mAs to 30 mAs at an interval of 10 mAs in each image acquisition, it was measured standard deviation (SD) of CT number, high contrast resolution and low contrast resolution, and then analyzed the relationship between the three parameters and the mAs values. Three mAs values were chosen to undertake clinical analysis.Clinical analysis: 90 randomly selected objects with abdominal angiography were divided into three groups,scanning with above three mAs values.Measurement of the SD value at the plain scan images was performed and the enhanced low-dose scan images were used post-processing with three-dimensional volume reconstruction (VR). The VR images were classified into three grades (excellent, moderate, bad) with the blind evaluation of three CT radiologists. The quality-correlation analysis was used between the standard deviation (SD) values of plain scan image and abdominal angiography VR image. Results According to the quality-correlation analysis between the standard deviation (SD) value of plain scan image and abdominal angiography VR image, the area under curve in receiver-operated characteristic (ROC) analysis was 0.921, 0.906 and 0.893 in each three group, respectively. Conclusions The low-dose scan of abdominal angiography is feasible. 80mAs can ensure better image quality. The enhanced scan probably can use 60mAs when the SD value is less than 5.78 in the plain scan; but when the SD value of plain scan is greater than 11.8, the enhanced scan is used best 100 mAs or higher.

Malignant renal angiomyolipoma with metastases (report of 3 cases) / 中华泌尿外科杂志

Objective To study the diagnosis and treatment of malignant renal angiomyolipoma with metastases. Methods Three cases of advanced malignant renal angiomyolipoma with metasta-ses were retrospectively reviewed. Case 1 was a 55-year-old woman presenting with recurrent low-grade fever and aching pain in left flank. Ultrasound showed solid mass in the left kidney. Left radical nephrectomy was then performed. The right pulmonary lobectomy of the inferior lobe and wedge ex-section of superior lobe was performed 7 years later because of multiple pulmonary metastases. Case 2 was a 37-year-old woman. Left nephrectomy was performed because Ultrasound and CT showed left kidney solid mass. Six years later, multi-site metastases were found in liver and retroperitoneum and mestastasis tumors were resected. At 10 years after the primary diagnosis, CT showed multi-metasta-ses in liver and retroperitoneum. The retroperitoneal masses were resected and liver lesions were trea-ted by radiofrequency ablation. Case 3 was a 34-year-old man presenting with swelling pain in right flank. CT scan showed a lesion in the right kidney and right radical nephrectomy was performed. Four months after the surgery, MRI revealed multiple liver and retroperitoneal nodules. All the 3 cases had not been diagnosed with tuberous sclerosis and did not accept chemotherapy. Results The cut sur-face of the lesions was red-brown and yellow and the texture was tender. Under microscopic examina-tion, the tumors of case 1 and case 3 were composed of sheets or nests of large polygonal epithelioid cells. It revealed that occasionally clear cytoplasm with abundant eosinophilic, prominent nucleoli, and multinucleated and markedly pleomorphic form. Necrosis was presented as well. Large areas of case 2 tumor were made up of spindle smooth-muscle cells, adipose tissue, thick-wall blood vessels and some areas merged with a proliferation of epithelioid which was consistent with typical angiomyolipoma. Im-munohistochemical study showed that the epithelioid cells and spindle smooth-muscle cells were posi-tive for VM, HMB45, Melan-A and negative for S100, CK. Case 1 and case 3 were diagnosed with malignant epithelioid angiomyolipoma, while case 2 was diagnosed with malignant classic angiomyoli-poma and epithelioid in part of the tumor. Case 1 was well alive. Case 2 was alive with tumor 12 years after the diagnosis. And case 3 was missed in the follow-up 3 months after metastasis resection. Conclusions Malignant renal angiomyolipoma is a rare disease. The diagnosis depends on histopatho-logic, immunohistochemieal study and clinical follow-up. Radical resection of the primary, recurrent and metastatic tumors is the main therapy. It needs more research to clarify if metastasis has any effect on prognosis.

Diagnosis and prediction of early acute renal transplant rejection with blood oxygen level dependent magnetic resonance imaging / 中华肾脏病杂志

Objective To assess the value of blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI)in diagnosis and prediction of early acute renal transplant rejection.Methods BOLD-MRI was performed in a cohort of 103 patients undergoing cadaver renal transplantation between Dec 2005 and March 2007.Among them,82 recipients had nomlal renal function,21 had biopsy-proved acute rejection.R2* (1/s)measurements were obtained in the medulla and cortex of grafted kidneys. Results R2* values of the medulla were significantly lower in the acute rejection group[R2*=(14.02±2.68)/s]than that in the normally functioning transplants group [R2*=(16.66+2.82)/s],the difference between these two groups was significant (P＜0.01);ROC curve analyses suggested that medullary MR2* values could accurately identify acute rejection in the early post-transplantation period.In the normal functioning transplant group,those with lower medullary R2* values (MR2*＜14.9/s,n=23) had higher acute rejection rates than those with higher medullary R2* values (MR2*＞14.9/s,n=59) in the first 6 months following transplantation,but the difference between these two groups was not significant (17.39% vs 8.47%,P=0.259). Conclusions Mean R2* values in the medullary regions of grafted kidneys with BOLD-MPd may be a non-invasive diadynamic criteria with good sensitivity and specificity,and may be a valuable predictor of early acute renal transplant rejection.

Comparative Study of Focal Nodular Hyperplasia:Radiologic and Pathologic Features / 实用放射学杂志

Objective To explore the pathological and imaging characteristics of focal nodular hyperplasia(FNH) of liver.Methods 17 cases of FNH proven pathologically underwent triphase spiral CT scan,of them,10 cases underwent fast MR imaging.The pathological andimaging features were comparatively analysed.Results All lesions were a solitary globular or lobulated mass,the majority of cases wasapproximately 2~5 cm in diameter.On plain CT and MRI,FNH was classically seen as a solitary,homogeneous and slightly hypoattenuating or isoattenuating area in comparison with normal liver,slightly hyper-or isointense on T_2WI,intense homogeneous enhancement during the arterial phase of enhanced imaging,and hyperattenuating in 12 cases,hypoattenuating or isoattenuating in 6 cases in comparison with normal liver during venous and delayed phase.The central scar was showed in 11 cases during delayed phase and 8 cases showed delayed enhancement,4 cases had pseudocapsular like enhancement in delayed images.In histology,17 cases of FNH were well limited but nonencapsulated,the hyperplastic parenchyma of the liver was subdivided into small nodules surrounded by the fibrous septa,there was a central scar composedof fibrous connective tissue and malformed vessels of various caliber.Conclusion The typical FNH can be easily diagnosed,while theatypical cases should be differentiated from hepatocelluar adenoma,hepatocellular carcinoma and hemangiomas.

Preliminary Research on Quality Control of PACS Image Display Device / 实用放射学杂志

Objective To study the quality assurance(QA) and quality control(QC) of PACS image display device in the department of radiology equipped with PACS and radiology information system (RIS). Methods Routine maintenance and periodic calibration were performed using photometer and automatic calibration software according to American Association of Physicists in Medicine Task Group 18 (AAPM TG18) test patterns and evaluating criterion. Digital image and communication in medicine (DICOM) gray scale standard display function (GSDF) standard calibration ,maximum luminance and minimum luminance,luminance uniformity,display resolution and geometry distortion adjustment were performed quarterly on BARCO CRT displays. Results All the results were well conformed to the criteria recommended by the AAPM TG18. About 95 percents of radiological images were interpreted on the PACS diagnostic image display.Conclusion The QC program of PACS image display device is an essential to ensure high-quality in digital medical environment.