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31.
Knotting of intravascular catheters is an uncommon but a well‐recognized occurrence. The Swan–Ganz catheter (SGC) is the one that knots most commonly. A case of a knotted SGC is described in a patient with a persistent left‐sided superior vena cava, and we propose that the presence of a left‐sided superior vena cava is a risk factor for knot formation not previously reported. We review the published work on the risk factors for knot formation and on the techniques used to remove knotted SGC. We describe a technique using a gooseneck snare and Omni Flush catheter (Angiodynamics, Queensbury, NY, USA) to loosen and untie a knotted SGC.  相似文献   
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Thirteen anaemic children on dialysis were assessed to determine the incidence of cardiac changes in end stage renal failure. Nine children had an increased cardiothoracic ratio on radiography. The electrocardiogram was abnormal in every case but no child had left ventricular hypertrophy as assessed by voltage criteria. However, left ventricular hypertrophy, often gross, was found on echocardiography in 12 children and affected the interventricular septum disproportionately. Cardiac index was increased in 10 patients as a result of an increased left ventricular stroke volume rather than heart rate. Left ventricular hypertrophy was significantly greater in those on treatment for hypertension and in those with the highest cardiac index. Abnormal diastolic ventricular function was found in 6/11 children. Children with end stage renal failure have significant cardiac abnormalities that are likely to contribute to the high cardiovascular mortality in this group. Anaemia and hypertension, or its treatment, probably contribute to these changes. Voltage criteria on electrocardiogram are of no value in detecting left ventricular hypertrophy. Echocardiography must be performed, with the results corrected for age and surface area, in order to detect and follow these abnormalities.  相似文献   
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Rotator cuff tear: clinical experience with sonographic detection   总被引:5,自引:0,他引:5  
Soble  MG; Kaye  AD; Guay  RC 《Radiology》1989,173(2):319-321
Between June 1986 and April 1988, 86 sonographic examinations of the shoulder were performed on patients suspected of having rotator cuff tears. Major sonographic diagnostic criteria included (a) a well-defined discontinuity usually visible as a hypoechoic focus within the cuff, (b) nonvisualization of the cuff and (c) an echogenic focus within the cuff. Seventy-five patients underwent both sonography and arthrography. Compared with arthrography alone, ultrasound examinations enabled detection of 92% of rotator cuff tears (24 of 26 tears), with a specificity of 84% and a negative predictive value of 95%. Correlation was obtained in 30 of these patients who underwent surgery for rotator cuff tear or other soft-tissue abnormality. In this group, the sensitivity of sonography for detection of a tear was 93%, with a specificity of 73%, while for arthrography sensitivity was 87% and specificity was 100%. These data indicate that sonography is a useful, noninvasive screening procedure for patients suspected of having rotator cuff injury.  相似文献   
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Computed tomography of the pancreas   总被引:2,自引:0,他引:2  
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Background  

Chronic lymphocytic leukemia (CLL) is a monoclonal disorder, characterized by a progressive proliferation of functionally incompetent B lymphocytes. There is increased evidence of association between CLL and skin cancers, including the uncommon Merkel cell carcinoma (MCC).  相似文献   
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OBJECTIVE: To evaluate the results of cardiosurgical treatment of children with Down's syndrome and a complete atrioventricular septal defect (cAVSD). DESIGN: Retrospective. METHOD: Data were collected from the records of all patients with Down's syndrome who had been subjected to primary corrective surgery for cAVSD in the period 1980-2003 in Leiden, The Netherlands. Exclusion criteria were: concomitant tetralogy of Fallot or interruption of the aortic arch and palliative banding of the pulmonary artery. Children with an abnormal shape of the ventricle making it impossible to correct biventricularly were not considered in the study. Data on mortality >30 days after the operation and on repeated surgery were included in the analysis if the duration of follow-up was at least 5 years. RESULTS: The group comprised 148 children: 75 girls and 73 boys. The median age at time of surgery was 20 weeks (range: 6 weeks to 3.7 years) and showed a statistically significant decrease during the period under investigation. Of 4 children lost to clinical follow-up actual data could be obtained. The median duration offollow-up was 6 years and 7 months (range: 38 days to 23 years and 11 months). 28 children (19%) died. The mortality within 30 days after the operation decreased from 0-38% in the period 1980-1989 via 0-30% in the period 1990-1999 to 0% in 2000-2003. The percentage ofreoperations related to the correction ofcAVSD (14%; 14/98) did not seem to increase. Of the correction-related reoperations, 14% (2/14) were followed by a second reoperation. Conclusion. In the period 1980-2003, children with Down's syndrome and a cAVSD were corrected surgically at a younger and younger age. The early mortality decreased to 0% in the years 2000-2003. Echocardiography in the first weeks of life for all children with Down's syndrome makes it possible to diagnose those with a cAVSD early enough for surgical repair.  相似文献   
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