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61.
PURPOSE: To prospectively assess accuracy of magnetic resonance (MR) imaging, MR cholangiopancreatography (MRCP), and MR angiography in patients suspected of having pancreatic tumors. MATERIALS AND METHODS: Sixty-six patients suspected of having pancreatic tumors underwent MR imaging (unenhanced and contrast material-enhanced MR, MRCP, and contrast-enhanced MR angiography). Two blinded readers prospectively analyzed the images by consensus, and results were correlated with surgery, biopsy, or follow-up findings. Results were tabulated in two-by-two tables. RESULTS: MR assessment of pancreatic lesion status (differentiation of benign vs malignant) resulted in 60 correct diagnoses (accuracy, 91%), and six (10%) false diagnoses. Among histologically proved malignant tumors, MR imaging yielded correct diagnoses in 42 of 44 patients (sensitivity, 95%; 95% CI: 85%, 99%), whereas 18 of 22 patients with benign findings were classified correctly. At MR imaging, findings in four patients with chronic pancreatitis were wrongly categorized as malignant tumors (specificity, 82%; 95% CI: 60%, 95%), and in one patient, a distal common bile duct carcinoma was not detected. In no patient with pancreatic adenocarcinoma was this tumor misdiagnosed as benign. In patients with malignant tumors who underwent resection, local-regional tumor growth and vascular infiltration were accurately classified in 89% and 94%, respectively. MR imaging depicted histologically proved synchronous hepatic metastases in 82%. The positive and negative predictive values for cancer nonresectability were 90% and 83%, respectively, and the accuracy, sensitivity, and specificity were 85%, 69%, and 95%, respectively. CONCLUSION: Unenhanced and contrast-enhanced MR imaging with MRCP and MR angiography offers potential as a noninvasive tool for assessment of patients suspected of having pancreatic tumors.  相似文献   
62.
Urculo E  Alfaro R  Arrazola M  Astudillo E  Rejas G 《Neurosurgery》2004,54(2):505-8; discussion 508-9
OBJECTIVE AND IMPORTANCE: Repeated percutaneous balloon compression for the treatment of idiopathic trigeminal neuralgia is infrequent. When a second procedure is performed, the outcome is unknown. A patient developed an isolated trochlear nerve palsy after undergoing percutaneous trigeminal ganglion balloon compression for a second time. The mechanism of diplopia and the complications associated with this technique were studied. CLINICAL PRESENTATION: The patient was a 67-year-old woman with a history of medically refractory idiopathic trigeminal neuralgia involving all three divisions of the right trigeminal nerve. INTERVENTION: Percutaneous balloon compression was performed. Despite initial total relief from pain without complications, the patient again displayed manifestations of trigeminal neuralgia 3 months after the procedure. The pain disappeared after she underwent a second balloon compression procedure, but she developed an isolated trochlear nerve palsy, which spontaneously resolved in 2 months. CONCLUSION: Isolated trochlear nerve palsy is a rare and reversible complication after percutaneous balloon compression for trigeminal neuralgia. This case illustrates that the mechanism of injury to the fourth nerve is the result of an erroneous technique: excessive penetration of the Fogarty catheter in Meckel's cave beyond the porus trigemini and compression of the cisternal segment of the trochlear nerve when the inflated balloon is pushed against the tentorium.  相似文献   
63.
BACKGROUND: Serum protein profiling patterns can reflect the pathological state of a patient and therefore may be useful for clinical diagnostics. Here, we present results from a pilot study of proteomic expression patterns in hemodialysis patients designed to evaluate the range of serum proteomic alterations in this population. METHODS: Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) was used to analyze serum obtained from patients on periodic hemodialysis treatment and healthy controls. Serum samples from patients and controls were first fractionated into six eluants on a strong anion exchange column, followed by application to four array chemistries representing cation exchange, anion exchange, metal affinity and hydrophobic surfaces. A total of 144 SELDI-TOF-MS spectra were obtained from each serum sample. RESULTS: The overall profiles of the patient and control samples were consistent and reproducible. However, 30 well-defined protein differences were observed; 15 proteins were elevated and 15 were decreased in patients compared to controls. Serum from 1 patient exhibited novel protein peaks suggesting possible additional changes due to a secondary disease process. CONCLUSION: SELDI-TOF-MS demonstrated consistent serum protein profile differences between patients and controls. Similarity in protein profiles among dialysis patients suggests that patient physiological responses to end-stage renal disease and/or dialysis therapy have a major effect on serum protein profiles.  相似文献   
64.
The treatment of gastroesophageal reflux (GERD) has improved dramatically in recent years. The new endoluminal treatments may bring a relatively simple, minimally invasive therapy that can be simultaneously applied in patients with GERD undergoing diagnostic upper endoscopy. Although the initial results are promising, these new techniques are generating some controversy and require further evaluation with randomized studies and longer follow-ups to define their precise role in the long-term management of the gastroesophageal reflux disease.  相似文献   
65.
OBJECT: The aims of this study were to analyze the relevance of risk factors in mild head injury (MHI) by studying the possibility of establishing prediction models based on these factors and to evaluate the reliability of the clinical guidelines proposed for the management of MHI. METHODS: A series of 1101 patients with MHI were prospectively enrolled in this study. In all cases clinical data were collected and a computerized tomography (CT) scan was obtained. The relationship between clinical findings and the presence of intracranial lesions was studied to establish prediction models based on logistic regression and recursive partitioning analysis. Recently proposed guidelines and recommendations for the treatment of MHI were selected, calculating their diagnostic efficiency when applying each of them to our series. The incidence of acute intracranial lesions was 7.5% (83 patients). A Glasgow Coma Scale score of 14, loss of consciousness, vomiting, headache, signs of basilar skull fracture, neurological deficit, coagulopathies, hydrocephalus treated with shunt insertion, associated extracranial lesions, and patient age greater than 65 years were identified as independent risk factors. Prediction models built on clinical variables were able to indicate patients with clinically important lesions, but failed to achieve 100% sensitivity in the detection of all patients with CT scans positive for intracranial lesions within reasonable specificity limits. CONCLUSIONS: Clinical variables are insufficient to predict all cases of intracranial lesions following MHI, although they can be used to detect patients with relevant injuries. Avoiding systematic CT scan indication implies a rate of misdiagnosis that should be known and assumed when planning treatment in these patients by using guidelines based on clinical parameters.  相似文献   
66.
To achieve sample sizes necessary for effectively conducting genome‐wide association studies (GWASs), researchers often combine data from samples possessing multiple potential sources of heterogeneity. This is particularly relevant for psychiatric disorders, where symptom self‐report, differing assessment instruments, and diagnostic comorbidity complicates the phenotypes and contribute to difficulties with detecting and replicating genetic association signals. We investigated sources of heterogeneity of anxiety disorders (ADs) across five large cohorts used in a GWAS meta‐analysis project using a dimensional structural modeling approach including confirmatory factor analyses (CFAs) and measurement invariance (MI) testing. CFA indicated a single‐factor model provided the best fit in each sample with the same pattern of factor loadings. MI testing indicated degrees of failure of metric and scalar invariance which depended on the inclusion of the effects of sex and age in the model. This is the first study to examine the phenotypic structure of psychiatric disorder phenotypes simultaneously across multiple, large cohorts used for GWAS. The analyses provide evidence for higher order invariance but possible break‐down at more detailed levels that can be subtly influenced by included covariates, suggesting caution when combining such data. These methods have significance for large‐scale collaborative studies that draw on multiple, potentially heterogeneous datasets. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
67.
Peripheral blood lymphocyte (PBL) count may reflect the immune status of cancer patients. We retrospectively analyzed the predictive and prognostic impact of baseline and post-chemotherapy PBL counts in a homogeneous group of 103 breast cancer patients treated with neoadjuvant chemotherapy (anthracyclines and taxanes). In univariate analysis, baseline PBL under 1500 × 10(6)/L (p = 0.013; hazard ratio [HR]: 2.80, 95%CI 1.24-6.61), and PBL decrease >200 × 10(6)/L after the first cycle of chemotherapy (p = 0.047; HR: 2.82, 95%CI 1.01-7.86) were significantly related to disease free survival. In multivariate analysis, both baseline PBL count less than 1500 × 10(6)/L (p = 0.034; HR: 3.32, 95%CI 1.09-10.02) and PBL decrease >200 × 10(6)/L after first cycle (p = 0.032; HR: 3.25, 95%CI 1.10-9.56) showed independent prognostic value for worse disease free survival. No effect was observed for overall survival. Our data support the relevance of pre- and post-chemotherapy PBL for breast cancer recurrence after neoadjuvant chemotherapy.  相似文献   
68.
This article presents the case of a 42-year-old man who presented with superior vena cava (SVC) syndrome due to fibrosing mediastinitis with multiple failed attempts at recanalization. We initially treated him with unilateral sharp needle recanalization of the right innominate vein into the SVC stump followed by stenting. Although his symptoms improved immediately, they did not completely resolve. Six months later, he returned with worsening symptoms, and venography revealed in-stent restenosis. The patient requested simultaneous treatment on the left side. The right stent was dilated, and a 3-cm-long occlusion of the left innominate vein was recanalized, again using sharp needle technique, homing into the struts of the right-sided stent. Following fenestration of the stent, a second stent was deployed from the left side into the SVC, and the two Y limbs were sequentially dilated to allow a true bifurcation anatomy (figure). The patient had complete resolution of his symptoms and continues to do well 6 months later.  相似文献   
69.
Background: In recent years, numerous scientific publications have endorsed the superiority of the ProSeal? laryngeal mask airway (PLMA) over the Classic? laryngeal mask airway (cLMA) in adults, children, and infants. The PLMA forms a better seal for both the respiratory and gastrointestinal tracts, provides easier access to the gastrointestinal tract, and exerts lower mucosal pressures for a given seal pressure. This study aims to determine whether this superiority can also be observed for the size 1 PLMA used in anesthetized neonates and infants with positive pressure ventilation. Methods: Sixty consecutive neonates and infants undergoing elective surgical procedures were randomized to airway management with the size 1 PLMA or cLMA. For all patients, we recorded ease of insertion, effective airway time, number of placement attempts, oropharyngeal leak pressure, fiberoptic position, audible leaks, mask displacement, number of reinsertions during maintenance, gastric insufflation, and frequency of blood stain. Results: Ease of insertion, successful insertion in <3 attempts, fiberoptic position of the airway tube, and frequency of blood stain were similar in both groups. Effective airway time was lower for the PLMA group (30.5 vs 35.6 s). Oropharyngeal leak pressure was higher with the PLMA (32.9 vs 22.2 cm H2O, P < 0.001) and gastric insufflation less common (0% vs 6%, P = 0.492). There were fewer mask displacements during maintenance of anesthesia with the PLMA (0% vs 26.7%, P < 0.001). Mask reinsertion was not necessary during maintenance of anesthesia with the PLMA, although it was necessary in 14 cases in the cLMA group (0% vs 46%, P < 0.001). Audible leaks were less common with the PLMA (0% vs 46%, P < 0.001). Conclusions: We conclude that the size 1 PLMA is a stable, safe, and efficacious airway control device during neonatal and infant anesthesia, allowing higher peak airway pressure during positive pressure ventilation, with fewer mask displacements and gastric insufflations than the cLMA.  相似文献   
70.
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