The method of CT scanning of parathyroid adenoma were elucidated. CT findings of 15 cases with parathyroid adenoma, cperatively and pathologically verified, were reviewed. The correct localization of 12 adenomas (80%) was made by CT preoperatively. The enhancement curve of the adenoma was analysed and compared with the vascular enhancement curve.

Objective To analyze the correlation between renal blood flow (BF)of CT perfusion and effective renal plasma flow (ERPF)of radionuclide labeled microspheres.Methods CT perfusion was applied to 26 cases of renal cell carcinoma (RCC)in order to obtain the average unit BF of the target layer of the uninjured lateral kidney.For the renal image of the uninjured lateral kidney in the nephrographic phase (NP),we used the value of maximal renal cross-sectional area times the value of renal maximal height as the standardized volume.The product of this standardized volume and average unit BF could be used as an approximation of total re-nal blood flow,which was a standardized renal BF value.Meanwhile,we took radionuclide labeled microspheres into practice to ob-tain an ERPF value of the corresponding uninjured lateral kidney.The correlation between standard renal BF and ERPF was obtained by using Pearson chi-square test.Results The standard renal BF values of the uninjured lateral kidney for the group of 26 cases of RCC ranged from 620.59 to 820.76 mL·min-1 ·g-1 ·cm3 (mean=718.87 ±58.40 mL·min-1 ·g-1 ·cm3 ),and the values of ERPF tested by radionuclide labeled microspheres ranged from 244 to 41 1 mL/min (mean= 320.54 ± 55.71 mL/min).The two groups were positively correlated (r=0.754,P <0.01).Conclusion CT perfusion imaging of the kidney,to some extent,has the potential to replace renal functional examination of radionuclide labeled microspheres.

Objective To analyze the correlation between the metal components and MRI signal intensities of gallstones, to investigate the causes of gallstone signal features on MRI. Methods The MRI data and the metal components of the gallstones in vivo and in vitro of 30 patients were retrospectively analyzed. The MR sequences, namely 3D fast spoiled gradient-echo with fat saturation T1-weighted imaging (3D-FSPGR-FS T1WI), fast spoiled gradient-echo with fat saturation T1-weighted imaging(FSPGR-FS T1WI), fast imaging employing steady-state acquisition(FIESTA)and fast spin-echo T2-weighted imaging with fat saturation(FSE-FS T2WI), were performed on the gallstones in vivo and in vitro. According to the characteristics of the surface and cross section, gallstones were divided into pigment gallstones( n=16) and cholesterol gallstones(n=14). The MR signal characteristics of the gallstones were observed and the signal intensity rates of the gallstones were calculated. Preoperatively, the signal intensity rates of cholesterol and pigment stones of each MR sequence were compared by using t test and Mann-Whiteney U test. Postoperatively,the signal intensity rates of the fresh,dried and re-soaked gallstones were compared by using paired t test and Wilcoxon test. The correlation between the signal intensity rates of gallstones on the 3D-FSPGR-FS sequence and their metal components was analyzed by using Linear Regression analysis. Results The pigment gallstones showed high signal intensity on the 3D-FSPGR-FS T1WI. The signal intensity rates of the pigment gallstones were higher than the rates of the cholesterol gallstones on the 3D-FSPGR-FS T1WI, which were 2.02 ± 0.53 and 0.51 ± 0.24 (t=10.26,P< 0.01), respectively. On the 3D-FSPGR-FS T1WI, the signal intensity rates of the drying pigment stones were significantly lower than the rates of the fresh ones, the rates of the two states of the pigment gallstones were 0.21±0.06 and 1.42±0.35(t=13.49,P<0.01),respectively. The signal intensity rates of pigment gallstones showed significant rebound after re-soaking, the rates of the two states of the pigment gallstones were 0.21±0.06 and 1.68±0.86(t=-6.63,P<0.01),respectively. The metal components of pigment gallstones were significantly higher than the cholesterol stones. In the pigment gallstones and cholesterol gallstones, the medians of the Calcium were 28.186 and 2.347 mg/g(Z =-4.66,P< 0.01),respectively.For pigment gallstones, there was a significant correlation between the calcium and the signal intensity rate on 3D-FSPGR-FS T1WI. The regression equation of linear regression analysis was SI=65.40 logCa-166.67. Conclusions The pigment gallstones containing much more water and metal showed high signal intensity on 3D-FSPGR-FS T1WI. The Calcium in the pigment gallstones may be the main cause for this MR appearance.

Objective To investigate the value of diffusion-weighted imaging (DWI) in predicting and monitoring the response of uterine cervix cancer to concurrent chemoradiation. Methods Seventeen patients with uterine cervix cancer underwent conventional MRI and DWI examinations before therapy and at one month and two months after the initiation of concurrent chemoradiation, and 8 of them underwent additional examinations at 15 d after therapy. The longest diameter of tumor before and after treatment was measured on axial T2WI. The mean ADC value among pre- and post-treatment of each group (CR, PR and SD) was compared. Results The mean ADC value before therapy of CR group was statistically lower than that of PR group (P＜0.05). There was negative correlation between mean pretreatment ADC value and percentage size reduction of tumor after concurrent chemoradiation at two months (r=-0.574, P＜0.05). The percentage ADC change of tumor at one month correlated positively with percentage size reduction of tumor at two months after concurrent chemoradiation (r=0.572, P＜0.05). Fifteen days after the initiation of concurrent chemoradiation, the mean ADC value of 8 patients increased significantly, however, the longest diameter of tumor showed no statistically significant changes compared with pre-treatment tumor diameter. Conclusion DWI has the ability to predict the response of uterine cervix cancer to concurrent chemoradiation, and it can monitor the treatment response as well.

Objective To prospectively assess the diagnostic accuracy of MR inflow inversion recovery (IFIR) fast imaging employing steady-state acquisition (FIESTA) for detection of renal artery stenosis (RAS),as compared with renal artery CT angiography (CTA) performed as the reference standard.Methods Thirty patients [18 males,12 females; mean age (65.0±12.1) years] with arterial hypertension and suspected RAS were examined by 3.0-T 3D MR IFIR-FIESTA and renal artery CTA within a week.The IFIR-FIESTA image quality,the IFIR-FIESTA and CTA in display of second-order and third-order branches of renal artery were assessed by two experienced readers.The sensitivity,specificity,accuracy,and negative predictive value (NPV) of IFIR-FIESTA were calculated on artery-by-artery and patient-by-patient bases by the two readers.The inter-observer agreement between the two readers in determining the presence and grade of renal artery stenosis was assessed.Results The scores of qualification of IFIR-FIESTA image quality by reader A and B were (2.16±1.02) and (2.00 ± 0.14),there was no significant difference between them (Z=-0.037,P=0.971).IFIR-FIESTA and CTA in display of second-order and third-order branches of renal artery had no significant difference (x2 =0.298,P=0.585).In the assessment of all 64 main renal arteries by reader A,IFIR FIESTA on artery-by-artery basis had sensitivity,specificity,accuracy,and NPV of 100％,96％,97％,and 100％,respectively; the above parameters assessed by reader B were 100％,90％,93％,and 100％,respectively.There was excellent inter-observer agreement (Kappa=0.803) with the presence or absence of hemodynamically significant RAS.In the assessment of all 30 patients by reader A,IFIR-FIESTA on patient-by-patient basis had sensitivity,specificity,accuracy,and NPV of 100％,95％,97％,and 100％; the above parameters assessed by reader B were 100％,85％,90％,and 100％,respectively; there was good inter observer agreement (Kappa=0.724) with the presence or absence of hemodynamically significant RAS.Conclusions Compared with CTA,MR IFIR-FIESTA can excellently assess RAS without contrast material and radiation exposure,therefore,it can be used for screening of RAS,especially should be widely applied to elderly patients with arterial hypertension.

Objective To study the metabolic characteristic of prostate cancer(PCa) in peripheral zone (PZ) with three-dimensional proton MR spectroscopic imaging (3D MRSI),and to evaluate the value of 3D MRSI in the differential diagnosis of prostate cancer in PZ. Methods 3D MRSI findings were reviewed in 18 benign prostatic hyperplasia (BPH) cases and 21 PCa cases.(Cho+Cre)/Cit and Cho/Cre ratios of PCa and PZ of BPH were retrospectively measured,(Cho+Cre)/Cit and Cho/Cre of PCa voxels were compared with BPH voxels. Results PZ of BPH showed dominant Cit,which was markedly higher than Cho and Cre. Significantly higher choline levels and lower citrate levels were observed in PCa compared with that of BPH. It showed statistically significant difference between (Cho+Cre)/Cit ratios of PCa voxels and BPH voxels,PCa voxels had minimal overlap with BPH voxels. It also showed statistically significant differences between Cho/Cre ratio of PCa voxels and BPH voxels,but there was some overlap between two groups. Conclusion 3D MRSI can be successfully applied to the diagnosis of cancer in the PZ on the basis of the elevation of Cho and the reduction Cit in cancerous tissue compared with that of PZ tissue of BPH.

Objective To explore the value of MRI dynamic contrast-enhanced in differentiating adrenal adenomas from nonadenomas with washout rate of enhancement and the increased SI ratio. Methods Thirty-six patients with 41 adrenal masses enrolled into this study. All these masses underwent conventional T 1WI and T 2WI sequence first, and then FMPSPGR sequence through the center of each mass. Precontrast and dynamic contrast-enhanced FMPSPGR scans were preformed after administration of contrast material of Gd-DTPA intravenously. The signal intensity(SI) of masses was measured on the screen by electronic cursor. The washout rate of enhancement and increased SI ratio were compared between adenomas and nonadenomas. The differentiating adrenal adenomas from nonadenomas were carried out based on combination of the washout rate and the increased SI ratio, meanwhile, the sensitivity and specificity of the diagnosis of adenomas were evaluated well.Results The sensitivity and specificity of the diagnosis of adenomas were 74% and 73%,and accuracy was 73% when the washout ratio was used as a indicator at 5 min. The sensitivity and specificity of the diagnosis of adenomas would be improved markedly when the combination of the washout ratio and the increased SI ratio was used as a indicator.The sensitivity and specificity of the diagnosis of adenomas were 95%, 91% respectively,and accuracy was 93%. Conclusion Using MRI dynamic contrast-enhanced based on combination of washout rate of enhancement and the increased SI ratio,the diagnosis and differentiating diagnosis of adrenal adenoma and nonadenoma can be improved.

Objective To evaluate US, CT and 99mTc-MIBI in the localization of hyperfunctioning parathyroid tumors. Methods Among the 47 patients with primary hyperparathyroidism 45 underwent ultrasound, 47 did CT scan and 36 did double phase imagings. Results Forty-six adenomas, 2 adenocarcinomas and 2 hyperplastic glands were removed from 47 patients. The results showed that the sensitivities were 43%,78%,92% for B-utrasound; CT and isotope imaing respectively.The specificities were 96%,97%,100%;and the accuracies were 82%,92%,98%. There was significant difference between 99mTc- MIBI and CT (? 2=6.627,? 2=4.884,P

OBJECTIVE: This experiment aims to determine the diagnostic value of diffusion-weighted imaging (DWI) in the differentiation of axillary inflammatory lymph nodes from metastatic lymph nodes in rabbit models in comparison with conventional magnetic resonance imaging (MRI). MATERIALS AND METHODS: Conventional MRI and DWI were performed at 4 weeks after successful inoculation into the forty female New Zealand white rabbits' mammary glands. The size-based and signal-intensity-based criteria and the relative apparent diffusion coefficient (rADC) value were compared between the axillary inflammatory lymph nodes and metastatic lymph nodes, with histopathological findings as the reference standard. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance of the aforementioned criteria and rADC value in differentiating the axillary inflammatory lymph nodes from metastatic lymph nodes. RESULTS: Thirty-two axillary inflammatory lymph nodes and 46 metastatic ones were successfully isolated and taken into pathological analysis. The differences of the aforementioned criteria between the two groups were not statistically significant (p > 0.05). However, the rADC value of the inflammatory lymph nodes (0.9 +/- 0.14) was higher than that of metastatic ones (0.7 +/- 0.18), with significant difference (p = 0.016). When the rADC value was chosen as 0.80, the area under the ROC curve is greater than all other criteria, and the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for differentiating two groups were 86.2%, 79.3%, 81.2%, 84.2%, and 85.6%, respectively. CONCLUSION: Diffusion-weighted imaging is a promising new technique for differentiating axillary inflammatory lymph nodes from metastatic lymph nodes. Compared with routine magnetic resonance sequences, DWI could provide more useful physiological and functional information for diagnosis.
Animals ; Axilla ; Diagnosis, Differential ; Diffusion Magnetic Resonance Imaging ; Female ; Inflammation/pathology ; Lymphatic Metastasis/*pathology ; Magnetic Resonance Imaging/*methods ; Mammary Neoplasms, Experimental/*pathology ; ROC Curve ; Rabbits ; Sensitivity and Specificity

OBJECTIVETo study the CT findings of cystic nephroma (CN) and multilocular cystic renal cell carcinoma (MCRCC) and to improve the accuracy of preoperative diagnosis of these two diseases.

METHODSThe CT findings of nine CN cases and 19 MCRCC cases confirmed by pathology were blindly reviewed and compared with their pathological results. Fisher's exact test and independent-samples T test were applied to statistically analyze some of the CT features of the CN and MCRCC lesions.

RESULTSThe thickness of cystic walls and partitions in the nine CN cases ranged from 0.5 to 5 mm. Cystic walls and partitions were slightly thicker in some parts without visible mural nodules. Varying amounts of solid tissue could be found in all the 19 MCRCC tumors, and the cystic walls and partitions were found partially thickened ranging from 3 mm to 13 mm. Eight cases were with mural nodules (nodule diameter: 4.5-16 mm). Nine cases of CN tumors were lobulated and 7 protruded into the renal sinus. Three out of the 19 MCRCC presented shallow lobulation, and 7 tumors protruded into the renal sinus. The CT contrast-enhancement scanning displayed moderate delayed enhancement in the cystic walls and partitions in 8 cases. The enhanced scanning revealed that all the nine cases showed enhancement of the cystic walls and partitions, while 8 cases of them had mild to moderate delayed enhancement. The cystic walls, partitions and nodules were enhanced in 19 MRCC cases, among them 17 cases displayed obvious enhancement in the cortical phase. Among the differences of CT findings between MC and MRCC, the shallow lobulation, protruding into the renal sinus, mural nodules, cystic wall and partition thickness, and net growth in the cortical and nephrographic phase were statistically significantly different (P<0.05 for all).

CONCLUSIONSCT scan can provide significant evidence for CN and MCRCC diagnosis. CN cases usually present relatively thin and even cystic walls and partitions without mural nodules and with shallow lobulation and protruding into the renal sinus. The enhancement is mild to moderate, dynamic and delayed, while the opposite CT findings may indicate a higher possibility of MCRCC.

Adenocarcinoma, Clear Cell ; diagnostic imaging ; Carcinoma, Renal Cell ; diagnostic imaging ; Diagnosis, Differential ; Humans ; Kidney ; diagnostic imaging ; Kidney Diseases, Cystic ; diagnostic imaging ; Kidney Neoplasms ; diagnostic imaging ; Tomography, X-Ray Computed