Histogram Analysis of Diffusion Kurtosis Magnetic Resonance Imaging for Diagnosis of Hepatic Fibrosis

OBJECTIVE: To investigate the diagnostic value of diffusion kurtosis imaging (DKI) histogram analysis in hepatic fibrosis staging. MATERIALS AND METHODS: Thirty-six rats were divided into carbon tetrachloride-induced fibrosis groups (6 rats per group for 2, 4, 6, and 8 weeks) and a control group (n = 12). MRI was performed using a 3T scanner. Histograms of DKI were obtained for corrected apparent diffusion (D), kurtosis (K) and apparent diffusion coefficient (ADC). Mean, median, skewness, kurtosis and 25th and 75th percentiles were generated and compared according to the fibrosis stage and inflammatory activity. RESULTS: A total of 35 rats were included, and 12, 5, 5, 6, and 7 rats were diagnosed as F0–F4. The mean, median, 25th and 75th percentiles, kurtosis of D map, median, 25th percentile, skewness of K map, and 75th percentile of ADC map demonstrated significant correlation with fibrosis stage (r = −0.767 to 0.339, p < 0.001 to p = 0.039). The fibrosis score was the independent variable associated with histogram parameters compared with inflammatory activity grade (p < 0.001 to p = 0.041), except the median of K map (p = 0.185). Areas under the receiver operating characteristic curve of D were larger than K and ADC maps in fibrosis staging, although no significant differences existed in pairwise comparisons (p = 0.0512 to p = 0.847). CONCLUSION: Corrected apparent diffusion of DKI histogram analysis provides added value and better diagnostic performance to detect various liver fibrosis stages compared with ADC.

Imaging feature of computed tomography angiography in patients with coronary artery fistulas / 中华心血管病杂志

<p><b>OBJECTIVE</b>To analyzed the computed tomography angiography (CTA) features of the coronary artery fistulas.</p><p><b>METHODS</b>Sixty-six coronary artery fistulas were diagnosed out of 12 717 patients underwent the coronary artery multiple detector CTA examination. The origin and drainage site of the coronary artery fistulas and the plaque and stenosis of the coronary artery were observed by post-processing analysis on various images. Coronary artery angiography was performed in 14 out of 66 coronary artery fistulas patients.</p><p><b>RESULTS</b>Coronary artery fistulas arose from bilateral coronary artery system in 21 cases, from left coronary artery in 26 cases and from right coronary artery in 19 cases. The majority of coronary artery fistulas entered into pulmonary artery (41 cases). The rest drainage sites included left atrium (10 cases), right atrium (8 cases), left ventricle (4 cases), coronary sinus (2 cases) and right ventricle (1 case). The findings of CTA and coronary artery angiography were consistent in 14 patients with DSA examination. Coronary artery plagues were evidenced in 31 cases and stenosis was greater than 50% in 7 coronary artery fistulas patients.</p><p><b>CONCLUSIONS</b>Multiple coronary artery fistulas are not rare, and pulmonary artery is the most frequent drainage site. When suspecting the coronary artery fistulas, coronary artery CTA can be the first choice of diagnose. CTA can supply adequate information for therapy.</p>

Prediction of traumatic avascular necrosis of the femoral head by single photon emission computerized tomography and computerized tomography: an experimental study in dogs / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To evaluate the femoral head perfusion and to predict the traumatic avascular necrosis (AVN) of the femoral head by single photon emission computerized tomography and computerized tomography (SPECT/CT).</p><p><b>METHODS</b>Totally 18 adult beagle dogs were divided randomly into three equal-sized (n equal to 6) groups. Subsequently different degrees of ischemia model were developed by destroying blood vessels of the femoral head. The left hip received sham operation as normal control and the right hip underwent blood interruption. In Group A, the ligamentum teres was cut off. In Group B, the marrow cavity of the right femoral neck was destroyed while in Group C, the soft tissues at the base of the femoral neck were stripped in addition to the resection of the ligamentum teres and destruction of the marrow cavity. Three hours after surgery, SPECT/CT was performed. Laser Doppler Flowmetry (LDF) measurements were also obtained at three different time points (before operation, immediately and three hours after operation) in order to assess the change process of blood supply to the femoral head.</p><p><b>RESULTS</b>SPECT/CT showed no significant difference in the radionuclide uptake between the right and left femoral heads in Group A (t equal to -0.09, P equal to 0.94) and Group B (t equal to 0.52, P equal to 0.62). However, in Group C, it was 261+/-62 for the right femoral head, only 12% of that in the left femoral head. LDF measurements indicated that the femoral head perfusion was decreased from (45.0+/-3.3) PU to (39.1+/-3.7) PU in Group A,from (44.0+/-2.7) PU to (34.3+/-2.6) PU in Group B, and from (47.3+/-2.1) PU to (4.96+/-0.6) PU in Group C immediately after operation. However, the perfusion was restored and returned to normal values three hours after operation except in Group C.</p><p><b>CONCLUSION</b>SPECT/CT could assess the perfusion of the femoral head semiquantitatively, which might be useful in predicting the development of traumatic AVN.</p>

Isolated Noncompaction of Ventricular Myocardium: a Magnetic Resonance Imaging Study of 11 Patients

OBJECTIVE: To retrospectively summarize the cardiac magnetic resonance imaging (CMRI) findings of isolated noncompaction of ventricular myocardium (INVM). MATERIALS AND METHODS: Eleven patients (M:F = 9:2; mean age, 35 years) were evaluated. Steady-state free precession (SSFP), fast spin echo (SE) sequence, SSFP cine imaging, and delayed enhanced inversion recovery spoiled gradient echo (IR-SPGR) sequence were used for showing abnormal myocardium, measuring ratio of noncompacted/compacted myocardium layers (NC/C ratio), and detecting myocardial viability. The left ventricle was divided into nine segments and a NC/C ratio > 2.3 in diastole was used as cutoff value in diagnosing left INVM. The right ventricle was assessed qualitatively. RESULTS: Cardiac MRI indicated left INVM in seven patients, right INVM in one patient and biventricle INVM in three patients. Characteristic CMRI changes included prominent trabeculations, deep intertrabecular recesses and an increase in the NC/C ratio. The most frequently involved segments was left ventricular apex. Three patients had abnormal high signals within the trabecular structures on SE T2 weighted image. One ventricular aneurysm and one apical thrombus were also observed. Delayed enhancement was seen in six of nine patients with subendocardial and transmural patterns. CONCLUSION: There are CMRI features that might be characteristic for INVM.

Congenital coronary artery fistulas: dual-source CT findings from consecutive 6,624 patients with suspected or confirmed coronary artery disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Coronary artery fistulas (CAFs) are rare congenital abnormality often unintentionally found in patients with coronary artery disease. Clinical diagnosis of CAFs is difficult due to symptomless or lack of specific symptoms. Dual-source computed tomography (DSCT) might be a useful diagnostic tool for CAFs. The study aimed to retrospectively summarize the imaging features of CAFs delineated at DSCT in 48 CAF patients detected from consecutive 6624 patients with suspected or confirmed coronary artery disease in our institution.</p><p><b>METHODS</b>Forty-eight patients underwent DSCT angiography by using retrospective electrocardiographic (ECG) gating after infusion of 70 ml of intravenous contrast material during breath hold. Maximum intensity projection (MIP), curved planar reconstruction (CPR), and volume rendering technique (VR) were obtained. Anomalous termination of coronary artery in each subject was evaluated by two radiologists (with more than 10 years experience with cardiovascular imaging), and disagreement between diagnosis readers was settled by a consensus reading. Ten of 48 patients also underwent traditional coronary angiography (CAG) simultaneously.</p><p><b>RESULTS</b>In each CAF case, DSCT angiography clearly demonstrated the origin, the termination, the size of abnormal vessel and its course in relation to surrounding great vessels. CAF arising from right coronary artery was the most common type, left circumflex was the least one involved among three coronaries, and pulmonary artery was the most common drainage site. Aneurismal fistulous tract, coronary atherosclerosis, myocardial bridging and anomalous origin of coronary artery were also detected in this group. The demonstration of drainage sites in CAG was consistent with DSCT angiography in 9 patients, and judgment on one anomalous connection in CAG was inconsistent with that in DSCT angiography.</p><p><b>CONCLUSIONS</b>DSCT angiography could provide accurate delineation of anomalous communications, size and numbers of fistulas in patients with CAFs. It suggested that DSCT is a useful tool for the assessment of CAFs and may be considered as the first-choice imaging modality, especially for patients with coronary artery disease.</p>

Sixty-four-multi-detector computed tomography diagnosis of coronary artery anomalies in 66 patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The abnormalities of coronary arteries, though rare and sometimes benign, may first present clinically as myocardial infarction or sudden death. Multi-detector computed tomography (MDCT) is a non-invasive test that is highly suitable for detecting these anomalies. The study aimed to review the 64-MDCT appearance of the coronary artery anomalies in 66 patients and to discuss the clinical importance of these anomalies.</p><p><b>METHODS</b>In 6014 consecutive patients examined over 12 months by 64-MDCT for the study of coronary artery disease, 66 were diagnosed for coronary artery anomalies. All patients were symptomatic for one or more of the following diseases: chest pain, dyspnoea, palpitations, arrhythmia and myocardial infarction. Nine patients had undergone a coronary angiography. All the CT images were evaluated by two radiologists and one cardiologist. The right coronary artery (RCA) and the conus branch arising separately, myocardial bridging and duplication of arteries were not analysed in our study.</p><p><b>RESULTS</b>The incidence of coronary artery anomalies found in our study group was 1.097%. In the selected patients, seven different types of coronary anomalies were found by 64-MDCT examination. The high takeoff, origin of the coronary artery from the opposite or noncoronary sinus with an anomalous course, and coronary artery fistula were the three common forms of anomalies (n = 16, 18 and 16, respectively). Compared with the results of the coronary angiography, the number of the drainage sites of two coronary artery fistula was less in MDCT images (3 small sites in total). In all cases, coronary artery computed tomography angiography (CTA) technique was able to recognize the origin of the coronary artery, its three-dimensional course and its spatial relationship with the adjacent structures. Conventional coronary angiography in two cases, however, was unable to provide sufficient information for correct and complete diagnosis.</p><p><b>CONCLUSIONS</b>In conclusion, the study showed that 64-MDCT, especially the volume rendering technique (VRT), may be useful for the assessment of complex variations, even if the conventional angiography may not be sufficient. It may be considered as the first-choice imaging modality when an anomalous coronary artery is suspected.</p>

Acute hyperenhancement on delayed contrast-enhanced magnetic resonance imaging is the characteristic sign after coronary microembolization / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Detection of coronary microembolization is of clinical importance for patient management and prediction of long-term outcome. However, there are few studies of the changes of magnetic resonance imaging after coronary microembolization. This study was designed to investigate the imaging of the left ventricle using delayed contrast enhanced magnetic resonance imaging as well as the left ventricular ejection fraction after coronary microembolization in animal models.</p><p><b>METHODS</b>Eight miniswine, of either sex (body weight 21-25 kg), were used to make the coronary microembolization model. After coronary angiography, a 2.8F infusion catheter was placed in the left anterior descending artery with the tip located between the second and third diagonal branches. Microspheres with the diameter of 42 microm and mean dosage of 1.2 x 10(5) were selectively infused into the left anterior descending artery. First pass and stressed first pass perfusion scan were performed after cine images were acquired. Then a second bolus of 0.15 mmol/kg gadolinium DTPA was given at a rate of 2 ml/s. Ten minutes later, delayed contrast enhanced magnetic resonance images of the left ventricular wall were evaluated. Serum changes of tumor necrosis factor alpha (TNF-alpha) were evaluated by enzyme-linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>Hypoenhancement was not observed at first pass perfusion at the anterior wall of the left ventricle. Hyperenhancements of the anterior-septal and anterior wall of the left ventricle was in evidence on delayed enhancement images 6 hours after microembolization and disappeared one week later. The characteristic change of coronary microembolization on delayed contrast enhanced magnetic imaging was non-enhanced regions within the hyperenhancement zone. Left ventricular ejection fraction measured by magnetic resonance imaging decreased significantly from 0.451 +/- 0.063 at baseline to 0.362 +/- 0.070 at the sixth hour (P < 0.01), and recovered to 0.431 +/- 0.053 one week later (P < 0.01 vs 6th hour). Compared with baseline values, the left ventricular end systolic volume enlarged significantly at 6th hour and at one week after microembolization (P < 0.05 and P < 0.01 respectively). Serum TNF-alpha increased significantly at 6th hour (22.62 +/- 6.96) pg/ml compared with baseline (16.83 +/- 3.45) pg/ml (P < 0.05) and it further increased to (27.44 +/- 3.97) pg/ml at one week after coronary microembolization and was significantly higher than that at baseline (P < 0.01).</p><p><b>CONCLUSIONS</b>On delayed contrast enhanced magnetic resonance imaging, hyperenhancement of the anterior-septal and anterior wall of the left ventricle show at 6th hour but not at one week after coronary microembolization. This might represent the characteristic imaging after coronary microembolization. The left ventricular ejection fraction decreased at 6th hour and recovered one week later after coronary microembolization. Although impairment of left ventricular function could be recovered at 1 week after coronary microembolization, the left ventricular remodeling process still continued in concert with continuously elevation of serum TNF-alpha.</p>

CT and MRI imaging features of peripheral primitive neuroectodermal tumors / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the CT and MRI features of peripheral primitive neuroectodermal tumors (pPNETs) and evaluate its diagnostic value.</p><p><b>METHODS</b>The clinicopathological data of 9 surgically treated patients with peripheral primitive neuroectodermal tumors confirmed by pathology were collected, spiral CT (4/9) and MRI (6/9) plain scanning and dynamic enhancement scanning were performed preoperatively. Both CT and MRI scannings were performed in 1 case. Those CT and MR images were retrospectively reviewed and analyzed together with clinicopathological findings.</p><p><b>RESULTS</b>The 9 lesions were located in skeletal muscles (n = 6), pelvic cavity (n = 2) and thoracic cavity (n = 1). The tumor size was 7.4-18.3 cm in diameter with a mean diameter of 11.6 cm. The shape of those lesions was round or ellipse (4 lesions) and irregular (5 lesions). The tumor usually presented as ill-defined masses, with homogeneous (n = 2) or inhomogeneous density (n = 7). Seven cases, including the 3 lesions located in the chest and pelvis, showed obvious necrosis and multilocular cyst formation. The tumors showed iso-density as that of the adjacent muscles on CT plain scans and moderate heterogeneous enhancement after intravenous injection of contrast agents. The features of the tumors on the MRI including slightly low signal intensity on SE T1-weighted imaging, iso-signal intensity or slightly high signal intensity on FSE T2-weighted imaging and heterogeneous dynamic delayed contrast-enhancement with obvious necrosis in most of them. Six cases had a lesion in the skeletal muscles, presented as a giant ill-defined masse surrounding bone and extended along neural route with bone destruction to varying degrees.</p><p><b>CONCLUSION</b>Primitive neuroectodermal tumor is a kind of malignant tumor with proliferation of small, undifferentiated neuroectodermal cells, usually occurring in children or adolescent and frequently located in the extremities, chest cavity, pelvic cavity and chest wall. It typically presents as a large, ill-defined masse extending along neural route with heterogeneous and obvious enhancement after intravenous injection of contrast agents. The tumors located in the chest and pelvic cavities and some in the extremities show obvious necrosis and multilocular cyst formation, while some of the tumors in the extremities appear as homogeneous solid masses.</p>

Evaluation of the preoperative staging of rectal cancer by magnetic resonance imaging / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the value of MRI in preoperative staging of rectal cancer.</p><p><b>METHODS</b>The data of 156 rectal cancer patients,undergone MRI scans from December 2004 to June 2006 in our hospital, were analyzed retrospectively. Findings of MRI were compared with postoperative pathological examinations.</p><p><b>RESULTS</b>Intracavitary localized parenchyma tumors were seen in 72 cases, and intestinal wall abnormal incrassation or stricture in other 84 cases from MRI scan. Sixteen cases had rectal polyps simultaneously, 2 cases ovarian cysts, 13 cases anterior-sacral metastases and 2 cases bone metastases. The sensitivity and specificity of T(1-2), T(3) and T(4) rectal cancer by MRI examination were 25%(8/32), 93.3%(84/90), 94.1%(32/34) and 100%(124/124), 57.6%(38/66), 96.7%(118/122) respectively. In MRI imaging, metastatic para-rectal lymph node was diagnosed as the diameter >5 mm or abnormal border or mixed resonance, with a sensitivity of 85.1%(80/94) and specificity of 45.2%(28/62).</p><p><b>CONCLUSION</b>MRI has high accuracy for preoperative staging of rectal cancer, and is useful to detect the serosal infiltration and lymph node metastasis.</p>

Myocardial bridging detection by non-invasive multislice spiral computed tomography: comparison with intravascular ultrasound / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Invasive intravascular ultrasound (IVUS) is current diagnostic standard for myocardial bridging (MB). Non-invasive multislice computerized tomography coronary angiography (MSCT) technique has provided a good anatomical view of the tunnel artery now.</p><p><b>METHODS</b>A total of 51 consecutive patients with atypical or typical angina scheduled for IVUS were enrolled in this study and MSCT was performed 7 days before IVUS. Coronary imaging was quantified using IVUS and MSCT. Four main vessels (left main artery (LMA), left anterior descending (LAD), left circumflex (LCX), right coronary artery (RCA)) were examined.</p><p><b>RESULTS</b>Forty-one out of 51 (80%) patients received metaprolol (25 mg) before the MSCT scan and 25 of them were current beta-blocker users. The mean heart rate was (64 +/- 3) beats per minute. A total of 51 patients underwent IVUS examination (30 with MB and 21 without MB) were chosen for this study. Twenty-eight out of 30 MB cases were correctly diagnosed by MSCT and 2 patients with MB were not detected. Comparison with IVUS, the sensitivity of detection by MSCT was 93%, specificity was 100%. The lumen diameter of the tunnel artery derived from MSCT and IVUS significantly decreased from (2.9 +/- 0.3) mm to (2.4 +/- 0.4) mm (P < 0.001) and from (3.3 +/- 0.3) mm to (2.6 +/- 0.5) mm (P < 0.001), respectively. Minimal and maximal diameters of MB derived from MSCT were significantly smaller than those from IVUS ((2.4 +/- 0.4) mm vs (2.6 +/- 0.5) mm, P < 0.05 and (2.9 +/- 0.3) mm vs (3.3 +/- 0.3) mm, P < 0.05), respectively.</p><p><b>CONCLUSIONS</b>MSCT offers a reliable non-invasive method for MB in LAD and atherosclerosis diagnosis with diagnostic accuracy comparable with invasive IVUS.</p>

Comparison of MRI manifestations and histopathologic findings in pancreatic head carcinoma in vivo ex vivo / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To prospectively analyze the correlation of MRI image characteristics with histopathological findings in pancreatic head carcinoma in vivo and ex vivo.</p><p><b>METHODS</b>Sixteen patients with pancreatic head carcinoma were examined by 1.5T MRI. MR sequences included pre-and post-contrast dynamic 2D FLASH T1WI, TSE T2WI + fat suppressed (FS). All fresh specimens were scanned again within an hour after resection during the Whipple procedure, and were then cut into slices along the direction of MRI scan. The MRI image characteristics were compared with gross and histopathologic findings of the specimens.</p><p><b>RESULTS</b>The tumor size ranged from 1.5 cm x 2.0 cm to 4.8 cm x 4.2 cm with a mean value of 3.6 cm x 3.1 cm. The MRI findings in vivo showed hypointensity in 14 lesions and isointensity in 2, and on 2D FLASH T1WI and TSE T2WI, all lesions displayed mixed intensity except 3 lesions with iso-intensity. During post-contrast dynamic pancreatic parenchymal phase, 15 lesions showed mild enhancement and 11 lesions had ring enhancement sign. Nine lesions displayed progressive irregular moderate enhancement during post-contrast dynamic hepatic phase. Four lesions showed enhancement with iso- and hyperintensity in post-contrast dynamic delayed phase. The MRI findings demonstrated that all lesions ex vivo had hypointensity on 2D FLASH T1 WI and mixed intensity on TSE T2WI + FS. Tumor tissues mainly displayed hypointensity, and the area containing tumor and inflammatory tissue showed iso-intensity on 2D FLASH T1WI. On T2WI + FS, the fibrosis proportion displayed hypo or isointensity, while the tumor and chronic inflammatory tissue demonstrated slight hyperintensity, and the zones of mucous degeneration or pancreatic ductal dilatation displayed hyper-intensity. The ring enhancement of tumor was caused by multiple factors and no obvious enhancement within tumor and fibrosis area were observed during post-contrast dynamic pancreatic parenchymal phase. Progressive irregular enhancement originated from desmoplastic reaction within the tumor during post-contrast dynamic hepatic phase and delayed phase, respectively.</p><p><b>CONCLUSION</b>Pancreatic head carcinomas contain various kinds of tissues. MRI can reveal these pathologic characteristics. No obvious hemorrhage and necrosis within the tumor were observed in this series.</p>

Value of multidetector computed tomography in differentiating ovarian tumors from non-ovarian masses / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the ability of multidetector computed tomography (MDCT) in differentiating ovarian tumors from non-ovarian masses.</p><p><b>METHODS</b>Forty-two cases with pelvic masses were examined with 16-row MDCT. All source image of each case was put into workstation for multi-planar reconstruction (MPR) and curved planar reconstruction(CPR). Axial image combined with 2D image was used for determining the relationship of the mass to ovarian vascular pedicle and identifying the normal ovary, which was compared with postoperative pathologic result and the finding during operation. All the data was compared using Fisher's exact test.</p><p><b>RESULTS</b>There were 28 ovarian tumors and 14 non-ovarian tumors in this series. If the ovarian vascular pedicle sign was used for determining whether the tumor was from the ovary or not, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy was 89.3%, 85.7%, 92.6%, 80.0% and 88.1%, respectively, with a significant difference in differentiating the tumor from the ovary or non-ovarian organs (P <0.05). If the identification of full normal ovary was used to determine non-ovarian origin of the tumor, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy was 50.0%, 100.0%, 100.0%, 80.0% and 83.3%, respectively, also with a significant difference in differentiating the tumors from the ovary or non-ovarian organs (P <0.05).</p><p><b>CONCLUSION</b>MDCT can clearly show the relationship of the tumor to the normal ovary and its vascular pedicle, which is very helpful in differentiating the ovarian tumors from a non-ovarian masses.</p>

MRI in the evaluation of peripancreatic vessel invasion and resectability of pancreatic carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the role of MRI in evaluating the peripancreatic vessel invasion and resectability of pancreatic carcinoma based on the comparison of MRI image with surgical exploration, and try to establish the criteria for assessment of the sensitivity, specificity and accuracy of resectability.</p><p><b>METHODS</b>Forty-one pancreatic carcinoma patients confirmed by pathology received preoperative plain and contrast enhanced MRI scan, and 37 of them had additional coronal MRA scan. Peripancreatic vessel invasion was preoperatively assessed based on MRI features, and the vessel invasion degree from the uninvolved to the severely involved was divided into 6 grades represented by 1, 2a, 2b, 3a, 3b and 4, respectively. Compared with the findings during the surgery, the sensitivity and specificity of each vessel invasion grade were studied and the receiver operator characteristic curve (ROC) was drawn. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of resectability evaluation based on 2 and 2a degree were calculated respectively. The resectability of involved arteries and veins of grade 2 were also analyzed.</p><p><b>RESULTS</b>Of the 41 patients, 22 had resectable tumor, with 20 curative resection and 2 palliative. Compared with the findings during surgery, seven vessels including three arteries and four veins were not correctly interpreted by MRI. If grade 1,2a,2b,3a and 3b was used as the resectable standard,respectively, the sensitivity to predict the unresectbility was 78.3%, 84.8%, 67.4%, 56.5% and 47.8%, respectively. Receiver operator characteristic curve demonstrated that grade 2a was the optimal critical point. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of grade 2a in predicting the unresectbility were 84.8%, 98.5%, 92.9%, 96.6% and 95.9%.</p><p><b>CONCLUSION</b>Our data showed that grade 2a (tumor involvement < 2 cm long and < 1/2 circumference of the vessel) may be more sensitive and accurate in predicting the resectability, which may be considered as the line of demarcation between the respectable and unresectable cases in clinical practice.</p>

Evaluation of 2D and 3D MRI imaging in the diagnosis of pancreatic carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate various kinds of sequences and modified dynamic contrast-enhanced MRI methods in the diagnosis of pancreatic carcinoma.</p><p><b>METHODS</b>Forty-nine pancreatic carcinoma patients proved by histopathology or clinical examination and follow-up underwent MR examination. Plain MR sequences included: T1-weighted 2D FLASH, T1 WI 3D VIBE, TSE T2 WI and HASTE with FS. Modified dynamic contrast-enhanced scanning procedures were coronal scaning with 3D FLASH and axial scaning using T1 WI 3D VIBE sequences in turn for the upper abdominal area and pancreatic area. The coronal imaging were used to obtain 3D peripancreatic vessels during arterial phase and portal vein phase scanning, respectively. The axial imaging were used to detect the tumor in pancreatic parenchymal phase and delayed phase scanning, respectively. Final scanning for the whole upper abdomen was performed using T1 WI 2D FLASH axial sequence.</p><p><b>RESULTS</b>(1) Of 49 lesions in these patients, 45 showed hypo-intensity and 4 iso-intensity on 3D VIBE. Forty-six lesions showed hypo-intensity and 3 isointensity on 2D FLASH. On TSE T2 + FS, lesion contour was not clear enough; 3 of them displayed isointensity, the other showed iso- or hyper-intensity. (2) During pancreatic parenchymal phase, 48 lesions showed hypo-intensity and 39 ring enhancement. Twenty-four lesions displayed marginal tubercle and inner compartment enhancement during portal vein and delayed phase. Six lesions showed iso- or hyper-intensity in delayed phase. (3) Thirty-seven patients underwent surgical exploration. MRI and MRA had a good correlation with surgical findings for peripancreatic vessels which were diagnosed as being invasive or noninvasive by tumors except three superior mesenteric arteries and four superior mesenteric veins being misdiagnosed.</p><p><b>CONCLUSION</b>As"one-stop-shop" MRI examination, modified MRI sequences consisting of dynamic coronal and axial contrast-enhanced scanning is feasible and helpful in diagnosing, staging and assessing the resectability for pancreatic carcinoma.</p>

Clinicopathologic analysis of 92 cases of pancreatic cystic neoplasm / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic and immunohistochemical features of cystic neoplasms of the pancreas.</p><p><b>METHODS</b>Ninety-two cases of cystic neoplasm of pancreas were retrieved from the Department archival file during the period from 1999 to 2005. Histologic features were studied and the tumors were typed according to WHO classification. Immunohistochemistry was also carried out using paraffin-embedded tissues.</p><p><b>RESULTS</b>The age of patients ranged from 16 to 80 years. The patients included 33 males and 59 females. The tumors varied from 2 cm to 21 cm in diameter. They consisted of intraductal papillary mucinous neoplasm (36/92), serous cystic neoplasm (18/92), solid pseudopapillary tumor (18/92), mucinous cystic neoplasm (14/92), cystic pancreatic ductal adenocarcinoma (4/92) and cystic pancreatic endocrine neoplasm (2/92). Immunohistochemical study revealed variable staining patterns, with frequent overlaps between different tumor types. In general, serous cystic neoplasm expressed MUC1, while mucinous cystic neoplasm was positive for MUC-5AC, intraductal papillary mucinous neoplasm for MUC-2 and cystic pancreatic ductal adenocarcinoma for MUC-1. On the other hand, solid pseudopapillary tumor expressed alpha-antitrypsin, alpha-antichymotrypsin, vimentin and progesterone receptor.</p><p><b>CONCLUSIONS</b>Accurate diagnosis of pancreatic cystic neoplasms requires correlation of clinical findings, radiologic examination, histologic features and immunostaining results. Pathologic distinction is important because of different prognostic significance. Two-thirds of pancreatic cystic neoplasms are premalignant or malignant and warrant surgical resection, whereas the remaining one-third (including pseudocyst and serous cystadenoma) are benign and can be treated conservatively.</p>

In vivo cardiac magnetic resonance imaging of superparamagnetic iron oxides-labeled mesenchymal stem cells in swines / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the feasibility of magnetic resonance imaging (MR) on detecting transplanted nanometer small superparamagnetic iron oxides (SPIO) labeled mesenchymal stem cells (MSCs) in swine model with acute myocardial infarction (MI).</p><p><b>METHODS</b>MSCs isolated from swine were incubated with nanometer SPIO for 24 hours and the third-passage MSCs were labeled with DNA dye 4'-6-diamidino-2-phenylindole (DAPI) and aliphatic red fluorescent dye PKH(26)-GL. Presence of small particles of SPIO in MSCs was assessed by Prussian Blue staining and electron microscopy. Three animals in each group received SPIO-labeled MSCs (5 x 10(5); 1 x 10(6); 2 x 10(6)) and MSCs without SPIO (1 x 10(6)) injections into the infarcted myocardium approximately 1 hour following left anterior descending coronary artery. MRI (1.5-T) was performed 20 to 24 hours post infarction in all animals and the animals were subsequently sacrificed for histology 1 hour post MRI.</p><p><b>RESULTS</b>In vitro Prussian Blue staining and electron microscopy examination revealed numerous iron particles in the cytoplasm of MSCs. Low signal intensity spots with the scanning T(2)(*)WI-Flash 2d sequence were detected in all SPIO-MSCs but not in SPIO-negative-MSCs injected myocardial sites in vivo with the clinical 1.5 T scanner. Prussian blue, DAPI and PKH(26) positive cells were detected histologically in sections corresponding to low signal intensity spots area shown on MRI.</p><p><b>CONCLUSION</b>Magnetically labeled MSCs transplanted in myocardial ischemia area of swine can be visualized in vivo with a clinical 1.5-T MRI and could be used for tracking SPIO-MSCs clinically.</p>

CT diagnosis of intraductal papillary mucinous tumor of the pancreas / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the CT and MRI manifestatitions of intraductal papillary mucinous neoplasm (IPMN) of the pancreas.</p><p><b>METHODS</b>Both clinical and imaging data of 12 pathologically confirmed intraductal papillary mucinous neoplasm, of the pancreas were retrospectively analyzed.</p><p><b>RESULTS</b>The pancreatic IPMN can be classified into two types based on CT image: the branch duct IPMN (n=7) originated from the head and uncinate process of the pancreas. The tumor consisted of lobulated or clustered small cyst lesions with septa among them, the wall and septa can be enhanced; the combined IPMN (n=5) involved branch ducts of the uncinate process as well as the main pancreatic ducts with dilatation (diameter: 4-7 mm), one of these involved the branch ducts along the pancreatic body. The pancreatic IPMN was mainly found in elderly patient with a chief clinical symptoms of abdominal pain and/or pancreatitis.</p><p><b>CONCLUSION</b>The intraductal papillary mucinous neoplasm of the pancreas enjoys specific features in CT and MRI image, which are helpful to the diagnosis.</p>

Imaging diagnosis of solid psedopapillary tumor of pancreas / 中华放射学杂志

Objective To retrospectively analyze and conclude the characteristics of imaging appearances of solid psedopapillary tumor of pancreas.Methods Among 7 cases with pathologically proved solid psedopapillary tumor of pancreas,6 cases underwent CT examinations of upper abdomen preoperatively,and the rest One had MRI examination.The mean age of these 7 cases(all female)was 30.7 years(range,14—44 years).Results The tumors were usually quite large in the largest diameter ranged from 2.8 to 15.9cm(mean largest diameter,7.9 cm);Tumors were all well demarcated,and 5 of them were of capsule on CT or MR imaging.All tumors were well-encapsulated on pathologic specimens, except for the capsule of 1 tumor was partially invaded;In 6 cases underwent CT examination,scattered, punctate and linear calcification were noted in the capsule of 2 tumors and the rim of another one;Except for 1 tumor was almost solid,the other 6 tumors contained both solid and cystic components;Scattered sheets of high attenuation shown in the cystic or solid parts on CT imaging in several cases and the high signal intensity on T_1-weighted MR imaging signified the possibility of bleeding in tumors,which then was testified by pathologic evaluation.Conclusion The solid psedopapillary tumor of pancreas has comparatively characteristic clinical and imaging features.

CT findings of primary adrenocortical carcinoma / 中华放射学杂志

Objective To explore the imaging features and dynamic CT findings of primary adrenocortical carcinoma and evaluating its clinical value.Methods All 11 cases patients with primary adrenocortical carcinoma confirmed by surgical pathology underwent spiral CT plain scanning and two phases dynamic enhancement scanning before operation.Contrast injection was done by using nonionic Omnipaque at a flow rate of 3 ml/s with a power injector.The CT images were reviewed and analysed retrospectively in comparison with surgical and pathological results.Results Five of 11 lesions were located in the right adrenal gland,6 in the left.The diameter of the tumors was 4.1—16.0cm with 2 cases10.0cm.The attenuation of the plain scans,two phases contrast scans was 21.9—46.7 HU(with a mean value of 35.3 HU),30.5—65.8 HU(mean value 47.1 HU),and 52.6— 97.0 HU(mean value 74.2 HU),respectively.Four were in the shape of capsule,6 reticular,1 slightly inhomogeneous masses.The irregular tumor vessels of 6 reticular masses were seen in the artery phase. Conclusion The dynamic CT features of primary adrenocortical carcinoma were obvious,dynamic SCT scans could suggest the diagnose.

CT diagnostic value of adrenal ganglioneuroma / 中华放射学杂志

Objective To explore the dynamic spiral CT findings of adrenal ganglioneuromas and to evaluate its clinical value.Methods All 7 cases patients with adrenal ganglioneuromas confirmed by surgical pathology underwent spiral CT plain scanning and two phases dynamic enhancement scanning before operation.The CT images were reviewed and analysed retrospectively in comparison with surgical and pathological results.Results Six of 7 lesions were located in the right adrenal gland,1 in the left.The diameter of the tumors was 3.7—7.5cm,with a mean diameter of 4.6cm.The CT value of the plain scans, AP phases and PVP phases was 16.2—31.7 HU(with a mean value of 24.3 HU),20.9—36.6 HU(with a mean value of 30.2 HU),and 27.4—45.5 HU(with a mean value of 36.0 HU),respectively.The masses were well defined and showed a tendency of wedging into the space between the adjacent organs and structures and encasing the large vessels such as IV,but didn't compress or occlude them.Conclusion The dynamic SCT features of adrenal ganglioneuromas were obvious,dynamic SCT scans could suggest the diagnose.