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Dobutamine stress echocardiography and thallium-201 myocardial perfusion scintigraphy are clinically useful methods for the evaluation of coronary artery disease (CAD). However, the relative merits of these imaging modalities in the evaluation of the extent of CAD after myocardial infarction have not been well studied. The aim of this study was to compare the accuracy of dobutamine stress echocardiography and simultaneous 201Tl single-photon emission tomography (SPET) imaging for the diagnosis and localization of CAD late after acute myocardial infarction. Dobutamine (up to 40 μg kg–1 min–1)-atropine (up to 1 mg) stress echocardiography in conjunction with stress-reinjection 201Tl SPET was performed for the evaluation of myocardial ischaemia in 90 patients with previous myocardial infarction who underwent coronary angiography. Significant CAD was predicted on bases of myocardial ischemia (new or worsening wall motion abnormalities on echocardiography and reversible perfusion defects on 201Tl SPET). Significant CAD (≥ 50% luminal diameter stenosis) was detected in 73 (81%) patients. The sensitivity, specificity and accuracy of echocardiography in detecting remote ischaemia for the diagnosis of remote CAD (present in 53 patients) were, respectively, 79% (CI 70%–88%), 85% (CI 77%–93%) and 81% (CI 73%–90%), while the corresponding figures for 201Tl SPET were 75% (CI 66%–85%), 78% (CI 69%–87%) and 76% (CI 67%–86%) respectively (P = NS vs echocardiography). The sensitivity, specificity and accuracy of echocardiography in detecting peri-infarction ischaemia for the diagnosis of infarct-related artery stenosis (present in 70 patients) were, rspectively, 77% (CI 68%–86%), 85% (CI 78%–92%) and 79% (CI 70%–87%) while the corresponding figures for 201Tl SPET were 73% (CI 64%–82%), 85% (CI 78%–92%) and 76% (CI 67%–84%) respectively (P = NS vs echocardiography). The agreement between the two methods for the diagnosis of peri-infarction and remote ischaemia was 70% (kappa = 0.37) and 80% (kappa = 0.59) respectively. It is concluded that dobutamine stress echocardiography and 201Tl SPET have comparable accuracy for the diagnosis of infarct related and remote CAD in patients with previous myocardial infarction. The agreement between the methods is higher for the diagnosis of remote CAD than for that of peri-infarction ischaemia. Received 17 October 1998 and in revised form 5 January 1999  相似文献   
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The value of radiography, ultrasound and magnetic resonance imaging (MRI) in detecting skeletal and intraspinal pathology was assessed in infants with anorectal malformations, and the need for spinal MRI examination in this group of patients was evaluated. Twenty-one infants were examined with radiography, ultrasound and MRI of the lower spine. The detection of skeletal and intraspinal abnormalities was compared for the three imaging modalities. Fifteen patients were normal in all three examinations. Radiography showed bony skeletal abnormalities in six children, although sometimes very subtle. By ultrasound both bony and cartilaginous malformations were detected in all six patients and by MRI in five patients. Five of the six children with skeletal abnormalities had intraspinal pathology, detected in all cases by ultrasound and MRI. However, the abnormalities were more clearly demonstrated by MRI than by ultrasound. Spinal radiographs must be examined carefully for abnormalities, because they can indicate the presence or absence of intraspinal pathology. Normal radiographic and sonographic appearance of spinal anatomy in children with anorectal malformation makes MRI superfluous, but if radiographs or ultrasound are abnormal, MRI should be used to accurately depict possible intraspinal pathology.

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BACKGROUND: The hand-carried cardiac ultrasound (HCU) device is a recently introduced imaging device, which may be potentially useful in the primary care setting. AIM: To test the screening potential of a HCU for the detection of left ventricular (LV) dysfunction by evaluating LV ejection fraction (LVEF) and inferior vena cava (IVC) collapse. Standard echocardiographic system (SE) and plasma brain natriuretic peptide (BNP) measurements were used as a reference. METHODS: Eighty-eight consecutive patients (56 male, aged 59+/-12 years) with suspected LV dysfunction were enrolled in the study. The HCU-LVEF was visually estimated and the SE-LVEF was derived by the Simpson's biplane method. A LVEF <40% represented LV dysfunction. An IVC collapse of <50% and BNP levels > or =15 pmol/l were considered abnormal. The correlation of HCU-LVEF, HCU-IVC and BNP to the SE-LVEF and SE-IVC was analysed independently using 2x2 tables. RESULTS: Six patients were excluded because of poor echo images. 19/82 patients had LV dysfunction. The HCU and BNP could identify 17 and 18 out of these 19 patients, respectively. The agreement for LVEF and IVC collapse between SE and HCU was 96% for both parameters. The sensitivity of IVC collapse, HCU-LVEF and BNP in identifying patients with LV dysfunction was 26, 89 and 94%, respectively. CONCLUSION: A HCU device can reliably be used as a screening tool for LV dysfunction.  相似文献   
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Backgound/Purpose: Evaluation of the feasibility of thoracoscopic correction of esophageal atresia with distal fistula. Methods: Eight consecutive neonates with esophageal atresia and distal fistula were treated thoracoscopically. Mean birth weight was 3,048 g (range, 2,140 to 3,770). The patients were intubated endotracheally and placed in a [frac34] left prone position. Three cannulae were inserted along the inferior tip of the scapula. CO2 was insufflated at a pressure of 5mm Hg and a flow of 0.5 L/min. The fistula was either clipped or ligated. The proximal esophagus was opened and an anastomosis was made over a 6F or 8F nasogastric tube with interrupted 5-0 Vicryl. Results: All procedures were completed thoracoscopically without major peroperative complications. The mean operating time was 198 minutes (range, 138 to 250). One patient had a major leak, resulting in a stormy postoperative course, but the leak healed on conservative treatment. This patient and 3 others had stenosis requiring dilatation, respectively, 3, 6, 12, and 1 times. The babies were fed after a median period of 8 days. The median hospital stay was 13 days. Conclusions: Thoracoscopic repair of esophageal atresia with distal fistula is feasible. Larger series are needed to determine the exact place of the thoracoscopic approach.  相似文献   
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