Comprehensive magnetic resonance imaging of the small and large bowel using intraluminal dual contrast technique with iron oxide solution and water in magnetic resonance enteroclysis

OBJECTIVE: The objective of this study was to improve delineation of small and large bowel (SB, LB) anatomy and pathology with postoperative or complex multisegmental inflammatory changes using dual-contrast-technique (DCT) for magnetic resonance enteroclysis (MRE) with luminal contrast media of opposed signal characteristics. MATERIALS AND METHODS: Sixty patients underwent MRE with iron oxide-based negative contrast in the SB. Thirty patients received additional rectal instillation of water for positive contrast (DCT). Two observers evaluated the degree of distention and the ease of identification of bowel anatomy and pathologies (none n=22, stenosis n=16, abscess n=4, fistulae n=5, postoperative changes and adhesions n=13) using a 4-point scale. Mann-Whitney U-test and kappa statistics were applied. RESULTS: LB and the terminal ileum were significantly better distended and identified with DCT (P相似文献   

Cardiovascular screening with parallel imaging techniques and a whole-body MR imager

The purpose of this study was to integrate parallel acquisition techniques into a comprehensive whole-body cardiovascular screening protocol to image all relevant organ systems without compromising spatial or temporal resolution. The study was approved by the institutional review board, and oral and written informed consent was obtained from each subject. Fifty subjects underwent whole-body magnetic resonance imaging that included imaging of heart, blood vessels, brain, lungs, and abdominal organs with a standard eight-channel imager. Image quality and pathologic findings were evaluated by two readers. The same protocol was then implemented with a new 32-channel whole-body imager. Depiction of 1476 (73.2%) of 2016 vessel segments was rated as good to excellent, and that of 1744 (86.5%), as without venous overlay. Interobserver agreement was good in evaluation of image quality and excellent in evaluation of pathologic findings. Acquisition time was reduced significantly (P < .05) with use of the whole-body imager and parallel acquisition techniques, which provided high-quality fast cardiovascular imaging.     

Dependency of magnetocardiographically determined fetal cardiac time intervals on gestational age,gender and postnatal biometrics in healthy pregnancies

Background  

Magnetocardiography enables the precise determination of fetal cardiac time intervals (CTI) as early as the second trimester of pregnancy. It has been shown that fetal CTI change in course of gestation. The aim of this work was to investigate the dependency of fetal CTI on gestational age, gender and postnatal biometric data in a substantial sample of subjects during normal pregnancy.     

High-resolution MR-imaging of the liver with T2-weighted sequences using integrated parallel imaging: comparison of prospective motion correction and respiratory triggering

PURPOSE: To compare high-resolution T2-weighted images of the liver with and without integrated parallel acquisition techniques (iPAT) using either breath-hold sequences in combination with prospective acquisition motion correction (PACE) or respiratory triggering. MATERIALS AND METHODS: Ten volunteers and 10 patients underwent each four different high-resolution fast spin echo (FSE) T2-weighted sequences with 5 mm slice thickness and a full 320 matrix: a multi-breath-hold FSE sequence with and without iPAT and PACE and a respiratory-triggered FSE sequence with and without iPAT. Image quality was rated with a five-point scale by two independent readers. Signal intensity measurements were performed on a water phantom. RESULTS: The sequences with iPAT required a substantially shorter acquisition time without loss of image quality. Overall image quality was rated equal for all sequences by both readers. Image time for nine slices with iPAT was 13 seconds (19 seconds without iPAT) with multi-breath-hold and on average 4:00 minutes (7:02 minutes without iPAT) with respiratory triggering. Imaging with the PACE technique resulted in more correct positioning of the image stacks. CONCLUSION: T2-weighted fast imaging with iPAT is feasible and results in high-quality images within a short acquisition time. Overall image quality is not negatively affected by iPAT.     

Perfusion CT in patients with advanced bronchial carcinomas: a novel chance for characterization and treatment monitoring?

Advanced bronchial carcinomas by means of perfusion and peak enhancement using dynamic contrast-enhanced multislice CT are characterized. Twenty-four patients with advanced bronchial carcinoma were examined. During breathhold, after injection of a contrast-medium (CM), 25 scans were performed (1 scan/s) at a fixed table position. Density-time curves were evaluated from regions of interest of the whole tumor and high- and low-enhancing tumor areas. Perfusion and peak enhancement were calculated using the maximum-slope method of Miles and compared with size, localization (central or peripheral) and histology. Perfusion of large tumors (>50 cm³) averaged over both the whole tumor (P=0.001) and the highest enhancing area (P=0.003) was significantly lower than that of smaller ones. Independent of size, central carcinomas had a significantly (P=0.04) lower perfusion (mean 27.9 ml/min/100 g) than peripheral ones (mean 66.5 ml/min/100 g). In contrast, peak enhancement of central and peripheral carcinomas was not significantly different. Between non-small-cell lung cancers and small-cell lung cancers, no significant differences were observed in both parameters. In seven tumors, density increase after CM administration started earlier than in the aorta, indicating considerable blood supply from pulmonary vessels. Tumor perfusion was dependent on tumor size and localization, but not on histology. Furthermore, perfusion CT disclosed blood supply from both pulmonary and/or bronchial vessels in some tumors.Abbreviations AIF arterial input function - CT computed tomography - CM contrast media - ROI region of interest - SCLC small-cell lung cancer - NSCLC non-small-cell lung cancer - SD standard deviation     

The selective use of basiliximab versus thymoglobulin in combination with sirolimus for cadaveric renal transplant recipients at low risk versus high risk for delayed graft function

BACKGROUND: We previously reported that the use of basiliximab together with sirolimus permits a window of recovery from delayed graft function before the introduction of reduced-dose cyclosporine. The present study reviews our experience with the substitution of thymoglobulin for basiliximab as induction therapy for recipients at increased risk for early acute rejection episodes. METHODS: We retrospectively reviewed 145 cadaveric renal allograft recipients who received either basiliximab (n=115) or thymoglobulin (n=30) in combination with sirolimus and prednisone, followed by delayed introduction of reduced doses of cyclosporine. Recipients were stratified as high immune responders if they were African American, a retransplant recipient, or a recipient with a panel-reactive antibody greater than 50%. All other recipients were considered low immune responders. RESULTS: Basiliximab-treated high immune responders exhibited a higher incidence of acute rejection episodes (26%) than either basiliximab-treated low immune responders (10%, P=0.04) or thymoglobulin-treated high immune responders (3%, P=0.01). The median time to initiation of cyclosporine was 12 days; cyclosporine was initiated when the serum creatinine level was 2.5 mg/dL or less. Patients with early return of renal function displayed a lower incidence of acute rejection episodes than those with later recovery of function (P=0.003). High immune responders treated with basiliximab expressed a higher mean serum creatinine level at 3 months (P<0.01), 6 months (P=0.02) and 12 months (P=0.01) than either low immune responders treated with basiliximab or high immune responders treated with thymoglobulin. CONCLUSION: A strategy combining sirolimus with basiliximab for low-immunologic risk recipients and thymoglobulin for high-risk recipients leads to prompt recovery of renal function with a low risk of acute rejection episodes.     

The effect of pancreas transplantation on peripheral vascular disease complications

BACKGROUND: We sought to determine whether pancreas transplantation reduced the incidence of peripheral vascular complications in diabetics with renal insufficiency. METHODS: A retrospective single-center review was done of 36 kidney-pancreas (KP) and 88 kidney-alone (KA) recipients with a diagnosis of diabetes and end-stage renal disease (ESRD) transplanted between May 1997 and July 2002. Risk factors studied included type of transplant, age, gender, history of smoking, coronary artery disease, hypertension, and peripheral vascular disease (PVD). The endpoint was first peripheral vascular event occurring after transplantation, defined as either an amputation or revascularization procedure. RESULTS: The mean age of the cohort was 51 +/- 9 years, 64% of patients were of male gender, 20% with a history of smoking, 98% with hypertension, 15% with coronary artery disease (CAD), and 12% with a history of PVD. With a median follow-up of 45 months (12 to 79 months), 3/36 (8%) of KP recipients suffered a PVD complication, compared to 10/88 (11%) of KA recipients (P = NS). Similarly, age, gender, a past history of smoking, CAD, and hypertension were not predictive of PVD complications. Five of 15 patients (33%) with a pretransplant history of PVD suffered a postoperative PVD event compared to only 8 of 109 patients (7%) with no prior history of PVD (P =.008). CONCLUSIONS: Restoration of normoglycemia by pancreas transplantation did not reduce the risk of PVD complications in diabetics with renal failure. A pretransplant history of PVD was the only risk factor associated with posttransplant PVD events.     

Preoperative somatic symptoms are associated with disease progression in patients with bladder carcinoma after cystectomy

BACKGROUND: A link between patient psychologic factors and bladder carcinoma outcome has not been demonstrated. The purpose of the current study was to assess the association of psychologic factors measured preoperatively with bladder carcinoma progression after cystectomy. METHODS: The Brief Symptom Inventory (BSI)-18 was administered prospectively to 65 patients with clinically localized bladder carcinoma before surgery. The BSI-18 measures distress in three specific domains-depression, anxiety, and somatization (i.e., distress due to somatic symptoms)-as well as general distress. Preoperative BSI-18 scores, tumor pathologic stage, and certain clinical variables were compared with disease status. Disease progression was defined as the development of either local disease recurrence or distant metastasis. Univariate and multivariate Cox proportional hazards models were constructed for statistical analysis. RESULTS: Of the 65 patients, 49 (79.4%) had no evidence of disease, 4 (6.2%) had local disease recurrence, and 12 (18.5%) had metastatic disease at last follow-up. The mean follow-up time was 1.3 years and did not differ significantly between survival outcomes (P = 0.577). Both tumor pathologic stage and preoperative somatic distress scores were associated with time to disease progression by univariate analysis (P = 0.038 and P = 0.055, respectively). After adjusting for tumor pathologic stage, a somatic distress score of > or = 2.00 was a significant predictor of disease progression (P = 0.044, hazard ratio = 3.31, 95% confidence interval = 1.03-10.60). Patient age, gender, reconstruction type, and BSI-18 scores for depression, anxiety, and general distress were not significantly associated with disease outcome. CONCLUSIONS: The authors found no correlation between psychologic symptoms measured preoperatively (i.e., depression, anxiety, and general distress) and bladder carcinoma progression. However, they reported an association between somatic symptoms and cancer outcome. If confirmed by other studies, these results may have important implications for the diagnosis, staging, and potential treatment of patients with bladder carcinoma.     

Differential estimation of verbal intelligence and performance intelligence scores from combined performance and demographic variables: the OPIE-3 verbal and performance algorithms

Data from the WAIS-III standardization sample (The Psychological Corporation, 1997) was used to generate VIQ and PIQ estimation formulae using demographic variables and current WAIS-III subtest performances. The sample (n = 2450) was randomly divided into two groups; the first was used to develop formulas and the second to validate the regression equations. Age, education, ethnicity, gender, region of the country as well as Vocabulary, Matrix Reasoning, and Picture Completion subtests raw scores were used as predictor variables. Prediction formulas were generated using a single verbal and two performance subtest algorithms. The VIQ OPIE-3 model combined Vocabulary raw scores with demographic variables. The PIQ estimation algorithm used Matrix Reasoning and Picture Completion raw scores with demographic variables. The formulas for estimating premorbid VIQ and PIQ were highly significant and accurate in estimation. Differences in estimated VIQ and PIQ scores were evaluated and the OPIE-3 algorithms were found to accurately predict VIQ and PIQ differences within the WAIS-III standardization sample.     

Hochauflösendes Ganzkörpertumorstaging unter Verwendung paralleler Bildgebung im Vergleich zur PET-CT

PURPOSE: To compare the accuracy in the detection and staging of various malignant tumors with high resolution whole-body MRI using parallel imaging with whole-body dual-modality PET-CT. PATIENTS AND METHODS: Preliminary results of an interim analysis from a prospective, blinded study are presented, in which 20 patients (mean age 59 years, range 27-77 years) with different oncological diseases underwent whole-body dual modality FDG-PET-CT screening for tumor search or staging in case of confirmed or suspected metastatic disease. All patients also underwent whole-body MRI imaging with the use of parallel imaging (iPAT). High-resolution coronal T1w- and STIR-sequences of 5 body levels with 512 x 512 matrix, axial fast T2w imaging of lung and abdomen (HASTE), contrast-enhanced dynamic and static T1w-sequences of liver, brain, abdomen, and pelvis were performed. Using a 32-channel whole-body MRI scanner (Magnetom Avanto, Siemens Medical Solutions) with a total field of view of 205 cm and free table movement, all patients could be covered from head to toe within one examination. With this technique, high spatial resolution and acceptable scanning times could be obtained. Two experienced radiologists read the MRI-scans, one radiologist and one nuclear scientist read PET-CT scans, each in consensus in a clinical setting. Delineation of the primary tumor (T-stage) or recurrent tumor, pathologic lymph node involvement, as well as degree and localization of metastatic disease, was assessed using PET-CT as standard of reference. RESULTS: Metastases from gastrointestinal tumor (25%) and breast cancer (25%), genitourinary tumor (15%) and malignant melanoma (15%) were detected. In 4/20 patients the primary tumor was identified, 2/20 patients showed recurrent tumor. Of 140 malignant lesions detected by PET-CT, 124 lesions were detected with MRI, resulting in a sensitivity of 89% at a specificity of 86%. In malignant lymph node detection, sensitivity of MRI was 83% and specificity 85%. CONCLUSION: Whole-body MRI is a promising technique in the detection of primary tumor and metastatic disease. Sensitivity in the assessment of lymph node metastases seems to be limited. With the use of parallel imaging (iPAT), dedicated high-resolution whole-body MRI is possible within acceptable scanning times.