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Tu'meh SS; Tracy DA; Wynne J; Konstam MA; Kozlowski JF; Neumann AL; Holman BL 《Radiology》1982,145(2):463-466
The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%. 相似文献
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Partik BL Leung AN Müller MR Breitenseher M Eckersberger F Dekan G Helbich TH Metz V 《AJR. American journal of roentgenology》2003,180(3):805-809
OBJECTIVE: Our aim was to evaluate the effectiveness of a commercially available dedicated lung-marker system for localization of pulmonary nodules before video-assisted thoracoscopic surgery. SUBJECTS AND METHODS: Guidewires were positioned under CT fluoroscopy guidance in 16 patients (11 men, five women; age range, 39-79 years; mean age, 60.4 years). We measured the size of the targeted nodule, its distance to the closest pleural surface, the angle between the introducer needle and the chest wall, and the time for performance of the procedure in each patient. Note was made of any complications after guidewire placement. RESULTS: In the 16 patients, the average nodule size was 6.7 mm (range, 3-12 mm), the average distance to the pleural surface was 10.6 mm (range, 3-22 mm), and the average pleural puncture angle was 59 degrees (range, 25-78 degrees). The marking procedure was completed within an average of 9.5 min (range, 7-15 min). Small pneumothoraces occurred in five (31.3%) of 16 patients. In 15 (93.8%) of 16 patients, thoracoscopic resection of the targeted nodule was successful; in one patient with dyspnea (6.3%), inaccurate localization resulting in an open thoracotomy occurred because an intervening fissure was not visualized. Dislodgement of the guidewire into the pleural space occurred in one patient (6.3%). CONCLUSION: The dedicated lung-marker system is a fast and effective method for localization of pulmonary nodules before thoracoscopic resection. 相似文献
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Videofluoroscopy of swallowing abnormalities in 22 symptomatic patients after cardiovascular surgery
Partik BL Scharitzer M Schueller G Voracek M Schima W Schober E Mueller MR Leung AN Denk DM Pokieser P 《AJR. American journal of roentgenology》2003,180(4):987-992
OBJECTIVE: The aim of this study was to evaluate the types of swallowing abnormalities that occur in symptomatic patients who have undergone cardiovascular surgery. MATERIALS AND METHODS: From 1994 to 2001, 22 patients (17 males and five females; age range, 4-89 years; mean age, 64 years) who had swallowing abnormalities after cardiovascular surgery were referred for a videofluoroscopic swallowing study. Each study was analyzed for functional abnormalities of the tongue, soft palate, epiglottis, hyoid and larynx, pharynx, upper esophageal sphincter, and esophagus. Also, the performance of transesophageal echocardiography, long-term intubation, or both was noted. RESULTS: Swallowing abnormalities were present in 18 patients (81.8%) (range, one to eight functional abnormalities; mean, 3.9 functional abnormalities). The distribution of abnormalities across the functional units statistically significantly deviated (chi(2) = 14.4; df = 6; p = 0.025) from uniform distribution, with abnormalities most commonly involving the hyoid and larynx (13 patients [59.1%]) and the pharynx (10 patients [45.5%]). Aspiration was found in 13 patients (59.1%) (predeglutitive, n = 1; intradeglutitive, n = 4; postdeglutitive, n = 3; and mixed, n = 5). In the 14 patients (63.6%) who underwent transesophageal echocardiography, long-term intubation, or both, we frequently found incomplete tilting of the epiglottis, pharyngeal weakness, and postdeglutitive aspiration. CONCLUSION: Most patients with swallowing problems after cardiovascular surgery present with multiple abnormalities that most commonly affect the hyoid and larynx and the pharynx and result predominantly in intra- or postdeglutitive aspiration. The performance of transesophageal echocardiography and long-term intubation may influence the types of swallowing abnormalities. 相似文献
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胰岛素样生长因子与胎儿宫内发育迟缓 总被引:1,自引:0,他引:1
0 引言 胎儿宫内发育迟缓(IUGR)是指出生体质量小于其孕龄平均体质量的第10百分位者,或者小于其平均体质量的两个标准差者.发病率约为3%~4%.IUGR是围产儿死亡的重要原因之一,新生儿期及远期发病率明显增高.在儿童期比正常儿体格和智力发育均落后.还有研究提示IUGR和成年期发生糖尿病及心血管病有因果联系[1].鉴于以上原因,IUGR的病因探讨越来越受到人们的重视,尤其是对IUGR内分泌方面的研究也越来越深入.本文着重综述近年来胰岛素样生长因子(insulinlikegrowthfact… 相似文献
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Intracranial abnormalities in infants treated with extracorporeal membrane oxygenation: imaging with US and CT 总被引:1,自引:0,他引:1
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis. 相似文献
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Postbiopsy renal transplant arteriovenous fistulas: color Doppler US characteristics 总被引:3,自引:0,他引:3
Color Doppler ultrasound (US) with point-spectral analysis was performed on eight patients with postbiopsy renal transplant arteriovenous fistulas. Waveform analysis of the supplying artery documented decreased resistive indices in all cases and increased flow velocities in seven. The peak-systolic flow velocity in the arteries supplying the fistulas ranged from 55 to 180 cm/sec (mean, 92 cm/sec), while the range in normal arteries was 20-52 cm/sec (mean, 32 cm/sec). The resistive indices of the arteries supplying the fistulas ranged from 0.31 to 0.50 (mean, 0.45), while the resistive indices of the normal arteries ranged from 0.60 to 0.92 (mean, 0.74). Arterialization of the venous waveform from the draining vein was also documented in all cases. In six cases, the increased flow velocities resulted in increased color saturation toward white in the supplying artery (n = 2) or in both the artery and the draining vein (n = 4), which was detectable on the realtime image. In six cases, flow turbulence resulted in localized tissue vibration, which appeared as random color assignment in extravascular renal parenchyma adjacent to the fistula. Knowledge of these imaging and Doppler characteristics should aid in the identification of renal transplant arteriovenous fistulas with color Doppler US. 相似文献