A nomogram for prediction of ERCP success in patients with bile duct leaks: a multicenter study.

BACKGROUND: Bile duct leaks (BDLs) are serious complications that occurs after hepatobiliary surgery and trauma, leading to rapid clinical deterioration. Endoscopic retrograde cholangiopancreatography (ERCP) is the first-line treatment for BDLs, but it is not clear which patients will respond to this therapy and which patients will require additional surgical intervention. The aim of our study was to explore the predictors of successful ERCP for BDLs. METHODS: A retrospective analysis was conducted using data from six centers' databases. All consecutive patients who were clinically confirmed as BDLs were included in the study. Collected data were demographics, disease severity, and ERCP procedure characteristics. Univariate and multivariate analysis were used to select independent predictive factors that affect the outcome of ERCP for BDLs, and a nomogram was established. Calibration and ROC curves were used to evaluate the models. RESULTS: Four hundred and forty-eight consecutive patients were clinically confirmed as BDLs and 347 were excluded. In the 101 patients included patients, clinical success was achieved in 78 patients (77.2%). In logistic multivariable regression, two independent factors were negatively associated with the success of ERCP: SIRS (OR, 0.183; 95% CI 0.039-0.864; P = 0.032) and high-grade leak (OR 0.073; 95% CI 0.010-0.539; P = 0.010). Two independent factors were positively associated with the success of ERCP: leak-bridging drainage (OR 4.792; 95% CI 1.08-21.21; P = 0.039) and cystic duct leak (OR 6.193; 95% CI 1.03-37.17; P = 0.046). The prediction model with these four factors was evaluated using a receiver-operating characteristic (ROC) curve, which demonstrated an area under the curve of 0.9351. The calibration curve showed that the model had good predictive accuracy. CONCLUSION: Leak-bridging drainage and cystic duct leak are positive predictors for the success of ERCP, while SIRS and high-grade leak are negative predictors. This prediction model with nomogram has good predictive ability and practical clinical value, and may be helpful in clinical decision-making and prognostication.

Intravoxel incoherent motion diffusion-weighted magnetic resonance imaging for predicting histological grade of hepatocellular carcinoma: Comparison with conventional diffusion-weighted imaging.

AIM: To compare intravoxel incoherent motion (IVIM)-derived parameters with conventional diffusion-weighted imaging (DWI) parameters in predicting the histological grade of hepatocellular carcinoma (HCC) and to evaluate the correlation between the parameters and the histological grades. METHODS: A retrospective study was performed. Sixty-two patients with surgically confirmed HCCs underwent diffusion-weighted magnetic resonance imaging with twelve b values (10-1200 s/mm2). The apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) were calculated by two radiologists. The IVIM and conventional DWI parameters were compared among the different grades by using analysis of variance (ANOVA) and the Kruskal-Wallis test. Receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic efficiency of distinguishing between low-grade (grade 1, G1) and high-grade (grades 2 and 3, G2 and G3) HCC. The correlation between the parameters and the histological grades was assessed by using the Spearman correlation test. Bland-Altman analysis was used to evaluate the reproducibility of the two radiologists' measurements. RESULTS: The differences in the ADC and D values among the groups with G1, G2, and G3 histological grades of HCCs were statistically significant (P < 0.001). The D* and f values had no significant differences among the different histological grades of HCC (P > 0.05). The ROC analyses demonstrated that the D and ADC values had better diagnostic performance in differentiating the low-grade HCC from the high-grade HCC, with areas under the curve (AUCs) of 0.909 and 0.843, respectively, measured by radiologist 1 and of 0.911 and 0.852, respectively, measured by radiologist 2. The following significant correlations were obtained between the ADC, D, and D* values and the histological grades: r = -0.619 (P < 0.001), r = -0.628 (P < 0.001), and r = -0.299 (P = 0.018), respectively, as measured by radiologist 1; r = -0.622 (P < 0.001), r = -0.633 (P < 0.001), and r = -0.303 (P = 0.017), respectively, as measured by radiologist 2. The intra-class correlation coefficient (ICC) values between the two observers were 0.996 for ADC, 0.997 for D, 0.996 for D*, and 0.992 for f values, which indicated excellent inter-observer agreement in the measurements between the two observers. CONCLUSION: The IVIM-derived D and ADC values show better diagnostic performance in differentiating high-grade HCC from low-grade HCC, and there is a moderate to good correlation between the ADC and D values and the histological grades.

Preliminary study of brain glucose metabolism changes in patients with lung cancer of different histological types.

BACKGROUND: Cerebral glucose metabolism changes are always observed in patients suffering from malignant tumors. This preliminary study aimed to investigate the brain glucose metabolism changes in patients with lung cancer of different histological types. METHODS: One hundred and twenty patients with primary untreated lung cancer, who visited People's Hospital of Zhengzhou University from February 2012 to July 2013, were divided into three groups based on histological types confirmed by biopsy or surgical pathology, which included adenocarcinoma (52 cases), squamous cell carcinoma (43 cases), and small-cell carcinoma (25 cases). The whole body 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) of these cases was retrospectively studied. The brain PET data of three groups were analyzed individually using statistical parametric maps (SPM) software, with 50 age-matched and gender-matched healthy controls for comparison. RESULTS: The brain resting glucose metabolism in all three lung cancer groups showed regional cerebral metabolic reduction. The hypo-metabolic cerebral regions were mainly distributed at the left superior and middle frontal, bilateral superior and middle temporal and inferior and middle temporal gyrus. Besides, the hypo-metabolic regions were also found in the right inferior parietal lobule and hippocampus in the small-cell carcinoma group. The area of the total hypo-metabolic cerebral regions in the small-cell carcinoma group (total voxel value 3255) was larger than those in the adenocarcinoma group (total voxel value 1217) and squamous cell carcinoma group (total voxel value 1292). CONCLUSIONS: The brain resting glucose metabolism in patients with lung cancer shows regional cerebral metabolic reduction and the brain hypo-metabolic changes are related to the histological types of lung cancer.

Susceptibility weighted imaging: a new tool in the diagnosis of prostate cancer and detection of prostatic calcification.

BACKGROUND: Susceptibility weighted imaging (SWI) is a new MRI technique which has been proved very useful in the diagnosis of brain diseases, but few study was performed on its value in prostatic diseases. The aim of the present study was to investigate the value of SWI in distinguishing prostate cancer from benign prostatic hyperplasia and detecting prostatic calcification. METHODOLOGY/PRINCIPAL FINDINGS: 23 patients with prostate cancer and 53 patients with benign prostatic hyperplasia proved by prostate biopsy were scanned on a 3.0T MR and a 16-row CT scanner. High-resolution SWI, conventional MRI and CT were performed on all patients. The MRI and CT findings, especially SWI, were analyzed and compared. The analyses revealed that 19 out of 23 patients with prostate cancer presented hemorrhage within tumor area on SWI. However, in 53 patients with benign prostatic hyperplasia, hemorrhage was detected only in 1 patient in prostate by SWI. When comparing SWI, conventional MRI and CT in detecting prostate cancer hemorrhage, out of the 19 patients with prostate cancer who had prostatic hemorrhage detected by SWI, the prostatic hemorrhage was detected in only 7 patients by using conventional MRI, and none was detected by CT. In addition, CT demonstrated calcifications in 22 patients which were all detected by SWI whereas only 3 were detected by conventional MRI. Compared to CT, SWI showed 100% in the diagnostic sensitivity, specificity, accuracy, positive predictive value(PPV) and negative predictive value(NPV) in detecting calcifications in prostate but conventional MRI demonstrated 13.6% in sensitivity, 100% in specificity, 75% in accuracy, 100% in PPV and 74% in NPV. CONCLUSIONS: More apparent prostate hemorrhages were detected on SWI than on conventional MRI or CT. SWI may provide valuable information for the differential diagnosis between prostate cancer and prostatic hyperplasia. Filtered phase images can identify prostatic calcifications as well as CT.

Measurement of tumor size in adult glioblastoma: classical cross-sectional criteria on 2D MRI or volumetric criteria on high resolution 3D MRI?

OBJECTIVE: To investigate the added value of volume on post-contrast three dimensional (3D) T1-weighted image (T1WI) over classical cross-sectional area on two dimensional (2D) T1WI in evaluating tumor response in glioblastoma multiforme (GBM). METHODS: Tumor cross-sectional area and volume measurements were performed on 104 MRI studies from 42 adult patients with GBM on post-contrast 5 mm 2D T1WI and isotropic high resolution 3D T1WI, respectively. 52 pairs of MRI scans were analyzed for relative change. Radiographic responses were determined based on change in either area or volume. RESULTS: A high correlation was revealed between tumor size measured by area on thick 2D and volume on high resolution 3D MRI in 104 scans (r=0.82, p<0.001). When four tumor response criteria were used according to the percentage changes (complete response/partial response/stable disease/progression), the kappa coefficient between the area on 2D and volume on 3D was 0.68 (p<0.05) with an overall agreement of 81%. CONCLUSIONS: Tumor cross-sectional area on post-contrast 2D T1WI appears comparable to volume on 3D T1WI and should still be a practical alternate of volume on 3D for evaluating tumor response.

Distinction between postoperative recurrent glioma and delayed radiation injury using MR perfusion weighted imaging.

INTRODUCTION: Distinction between postoperative recurrent glioma and radiation injury remains a tough diagnostic problem for routine imaging methods. The purpose of this study is to evaluate the differentiated effectiveness of perfusion weighted imaging (PWI) for the two entities. METHODS: PWI was performed using Siemens 3.0-T MR system for 35 patients with new contrast-enhancing lesions at the site of treated glioma. Regions of interest (ROIs) were manually drawn at the contrast-enhancing lesion and peri-lesion edema areas. For calculation of standardised relative cerebral blood volume (rCBV) ratios, the same size ROIs were drawn at the area of contralateral hemisphere normal white matter on rCBV maps. At least five ROIs were selected at each lesion. The rCBV values were measured and the rCBV ratios were calculated. The maximum rCBV (rCBV(max)) ratio at each region was chosen for analysis. The patients were divided into two groups: tumour recurrence and radiation injury. The mean rCBV(max) ratios were compared between the two groups. RESULTS: The mean rCBV(max) ratio in the contrast-enhancing lesion was significantly higher in the tumour recurrence (4.36 ± 1.98) compared with that (1.28 ± 0.64) in the radiation injury (P < 0.01). The mean rCBV(max) ratio in the peri-lesion edema was also significantly higher in the tumour recurrence (1.79 ± 0.51) compared with that (0.85 ± 0.28) in the radiation injury (P < 0.05). A recurrent tumour was suggested when the rCBV(max) ratio >2.15 based on the receiver operating characteristic curve. Four patients with recurrent tumour and three with radiation injury were misclassified. CONCLUSION: PWI is a useful method to distinguish tumour recurrence and radiation injury.

Comparison of volumetric methods for tumor measurements on two and three dimensional MRI in adult glioblastoma.

INTRODUCTION: Change in tumor size is a frequent endpoint in cancer clinical trials, but whether change in size should be measured using volume on two-dimensional (2D) or three-dimensional (3D) images is not certain. We compared volumetric measurements on post-contrast 2D and high-resolution 3D T1-weighted MR images (T1WI) in evaluating tumor response in glioblastoma multiforme (GBM). METHODS: Tumor volume measurements were performed on 86 MRI studies from 37 adult patients with GBM on post-contrast 5 mm 2D T1WI and isotropic high-resolution T1WI. The means of the two volumes were compared and their association was analyzed. RESULTS: There is no significant difference between volumes measured on 2D and 3D in 86 scans (Z = 0.63, p = 0.53), and a high correlation was revealed between them (r = 0.95, 95% CI: 0.93-0.97, p < 0.001). When the percentage changes were categorized into traditional tumor response criteria (complete response/partial response/stable disease/progressive disease), the kappa coefficient between the volume on 2D and volume on 3D was 0.80 (95% CI: 0.57-1.03, p < 0.05) with an overall agreement of 84%. CONCLUSIONS: Volume on post-contrast 2D T1WI appears comparable to volume on 3D T1WI and should be a practical alternative to volume on 3D in evaluating tumor response.

Distinction between postoperative recurrent glioma and radiation injury using MR diffusion tensor imaging.

INTRODUCTION: This study aims to evaluate the differentiated effectiveness of MR diffusion tensor imaging (DTI) to postoperative recurrent glioma and radiation injury. METHODS: Conventional MRI and DTI examination were performed using Siemens 3.0 T MR System for patients with new contrast-enhancing lesions at the site of treated tumor with postoperative radiotherapy. The region of interest was manually drawn on ADC and FA maps at contrast-enhancing lesion area, peri-lesion edema, and the contra-lateral normal white matter. Then ADC and FA values were measured and, the ADC ratio and FA ratio were calculated. Twenty patients with recurrent tumor and 15 with radiation injury were confirmed by histopathologic examination (23 patients) and clinical imaging follow-up (12 patients), respectively. The mean ADC ratio and FA ratio were compared between the two lesion types. RESULTS: The mean ADC ratio at contrast-enhancing lesion area was significantly lower in patients with recurrent tumor (1.34 ± 0.15) compared to that with radiation injury (1.62 ± 0.17; P < 0.01). The mean FA ratio at contrast-enhancing lesion area was significantly higher in patients with recurrent tumor (0.45 ± 0.03) compared to that with radiation injury (0.32 ± 0.03; P < 0.01). Neither mean ADC ratio nor FA ratio in edema areas had statistical difference between the two groups. A recurrent tumor was suggested when either ADC ratio <1.65 or/and FA ratio >0.36 at contrast-enhancing lesion area according to the receiver operating characteristics curve analysis. Three patients with recurrent tumor and two with radiation injury were misclassified. CONCLUSION: DTI is a valuable method to distinguish postoperative recurrent glioma and radiation injury.