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81.
Cerebral venous sinus thrombosis is a challenging condition because of its variability of clinical symptoms and signs. It is very often unrecognised at initial presentation. All age groups can be affected. Large sinuses such as the superior sagittal sinus are most frequently involved. Extensive collateral circulation within the cerebral venous system allows for a significant degree of compensation in the early stages of thrombus formation. Systemic inflammatory diseases and inherited as well as acquired coagulation disorders are frequent causes, although in up to 30% of cases no underlying cause can be identified. The oral contraceptive pill appears to be an important additional risk factor. The spectrum of clinical presentations ranges from headache with papilloedema to focal deficit, seizures and coma. Magnetic resonance imaging with venography is the investigation of choice; computed tomography alone will miss a significant number of cases. It has now been conclusively shown that intravenous heparin is the first-line treatment for cerebral venous sinus thrombosis because of its efficacy, safety and feasability. Local thrombolysis may be indicated in cases of deterioration, despite adequate heparinisation. This should be followed by oral anticoagulation for 3-6 months. The prognosis of cerebral venous sinus thrombosis is generally favourable. A high index of clinical suspicion is needed to diagnose this uncommon condition so that appropriate treatment can be initiated.  相似文献   
82.
Three cases with anomalous insertion of the superior or inferior vena cava into the right atrium are presented. One case was a 25-year-old healthy man with anomalous low insertion of the right superior vena cava into the right atrium. The remaining two cases were infants with complex cardiac anomalies showing anomalous high insertion of the inferior vena cava into the right atrium. The congenital anomalies of the connection between the superior and the inferior vena cava and the right atrium are rare. Angiographic and computed tomographic findings of these anomalies were reported.  相似文献   
83.
Peri-catheter calcification is an unusual and previously unreported complication of central venous (CV) catheterization in infants. A 1.9 Fr Silastic CV catheter was placed in a term infant for administration of total parenteral nutrition and antibiotics following intra-abdominal sepsis. The catheter was removed, without complication, at a later date after another septic episode. Imaging studies performed in the investigation of a possible intra-abdominal abscess revealed a cylindrical density within a clot in the inferior vena cava (IVC). The density was presumed to be a retained catheter fragment. Further investigation indicated total occlusion of the IVC. Surgical exploration of the IVC revealed only a calcified thrombus. This case represents a rare and previously unreported complication of CV catheterization in infants. Diagnosing this condition on radiographic evidence alone can be difficult. It is hoped that awareness of the potential for this complication will avoid unnecessary invasive procedures in the future. We also suggest a high level of clinical suspicion and routine Doppler ultrasound investigations to detect IVC thrombosis when indwelling CV catheters are used in infants. Accepted: 15 July 1997  相似文献   
84.
Cerebral venous sinus thrombosis: a clinical study of 23 cases   总被引:6,自引:0,他引:6  
Objective To describe the etiologies, clinical features and diagnosis of cerebral venous sinus thrombosis.
Methods
We reviewed the records of 23 patients admitted with a documented diagnosis of c erebral venous sinus thrombosis from 1991 through 1999 in the Beijing Tiantan Hospital.
Results
Infection was the major condition associated with cerebral venous sinus thrombos is. Pseudotumor cerebri syndrome was the most common manifestation, while hemip legia, seizure and unconsciousness may occur alone or in association. The diagn ostic sensitivity of computed tomography (CT), magnetic resonance imaging (MRI) and digital subtract angiography (DSA) were 59%, 86% and 100%, respectively. Th e sensitivity of MRI with magnetic resonance angiography (MRA) reached 96%.
Conclusion As the clinical findings were found to be nonspecific, CT combined with DSA, or MRI with MRA turns out to be valuable for the early diagnosis of cerebral venous sinus thrombosis.  相似文献   
85.
目的:研究红景天注射液治疗冠心病的药理作用及作用机制。方法:将实验犬20只,随机分为空白对照组、阳性药对照组和红景天注射液小、大剂量组。经戊巴比妥钠30mg·kg-1静脉麻醉后开胸,分别测定冠脉血流量、心输出量、左室内压、左室内压上升最大速率(dp/dtmax)、冠状静脉窦血氧含量、动脉血氧含量、心肌耗氧量、心搏出量、耗氧指数、心脏指数、冠脉阻力、总外周阻力及氧利用率等。结果:动物静脉注射红景天注射液后,冠脉阻力、动脉血压、总外周阻力、耗氧指数、心肌耗氧量、心率明显降低,心输出量、心搏出量及冠状静脉窦血氧含量明显上升,与药前及空白对照组比较均有显著性差异(P<0.05-0.01);左室内压和心肌收缩力则无明显改变。结论:结果表明,用红景天注射液可扩张冠脉血管、降低心脏后负荷,在不明显增加心肌收缩力和左心室压力的情况下,心输出量和每博出量明显增加,心脏有效作功得到加强;还能使冠状静脉窦血氧含量显著增加,心肌耗氧指数降低,心肌耗氧量下降,从而改善心肌的供血供氧,调整心脏血管的顺应性,对心血管系统起到调整和改善作用。这可能是红景天注射液治疗冠心病的药理机理。  相似文献   
86.
Wolff-Parkinson-White syndrome is important for the anesthesiologist because the sudden development of tachyarrhythmias may result in deleterious hemodynamic changes. We describe an episode of reciprocating tachycardia triggered by the insertion of the guide wire during central venous cannulation in a patient with this syndrome.  相似文献   
87.
BACKGROUND: Hepatic dysfunction is a common problem in patients after hemihepatectomy. Treatment with low-dose dopamine has been shown to be beneficial in hemihepatectomy patients. We hypothesized that dopexamine, a synthetic vasoactive catecholamine, due to its specific pharmocodynamic profile may be more effective in reducing hidden ischaemic episodes in the hepato-splanchnic region during and after temporary total cross-clamping of hepatic inflow in these patients. METHODS: The effects of low-dose dopexamine on hepatic venous haemoglobin oxygen saturation (ShvO2), hepatic venous lactate level, monoethylglycinxylid (MEGX) formation, hepatic synthetic function and indicators for hepatic cell damage were studied during hemihepatectomy and for 16 h postoperatively in hemihepatectomy patients and compared to those of low-dose dopamine. In a prospective, double-blind clinical study 20 patients received randomly either dopexamine (DPX) 0.5 microg kg(-1) min(-1) (n=10) or dopamine (DO) 2.5 microg kg(-1) min(-1) (n= 10). Infusions were started after induction of anaesthesia and continued 16 h postoperatively. Hepatic vein, radial and pulmonary artery were catheterized. Measurements were carried out after induction of anaesthesia, after total cross-clamping of hepatic inflow, and at 2 h and 16 h postoperatively. RESULTS: There were no differences in systemic haemodynamics, oxygenation, ShvO2, serum aminotransferases or MEGX levels between the groups. At 16 h postoperatively prothrombin and antithrombin III levels were significantly lower while hepatic venous lactate was significantly higher in the DPX group compared to the DO group. CONCLUSION: In patients undergoing hemihepatectomy, we could not reveal superior hepatoprotective effects of low-dose dopexamine compared to low-dose dopamine.  相似文献   
88.
不同参数激光诱导脉络膜视网膜静脉吻合   总被引:1,自引:0,他引:1  
目的 探讨不同激光参数、不同击射部位对脉络膜 视网膜静脉吻合形成的影响。方法 在视网膜分支静脉阻塞模型上 ,以不同参数在不同部位诱导吻合支的形成 ,以荧光素眼底血管造影、连续组织切片观察吻合支的建立及其周围组织反应情况。结果 功率 90 0、12 0 0、15 0 0、180 0mW诱导吻合支的成功率为 0、2 0 .83%、4 5 .83%、6 2 .5 0 % (P=0 .0 0 1) ;直径 5 0、10 0 μm诱导吻合支的成功率分别为 4 3.75 %、2 0 .83% (P =0 .0 16 ) ;击射部位距视盘边缘 2DD与 3DD对吻合支形成的影响无统计学意义 (P =0 .732 ) ,2DD与4DD间 (P =0 .0 2 8) ,3DD与 4DD间 (P =0 .0 2 3)差异均有显著性 ;12 0 0、15 0 0mW诱导的吻合支周围组织损伤较轻 ,180 0mW诱导的吻合支周围组织损伤较重。结论 功率、光斑直径是影响脉络膜 视网膜静脉吻合形成的 2个主要因素 ,其中功率起决定性作用 ;5 32nm激光诱导吻合支形成的最适功率和直径为 12 0 0~ 15 0 0mW、5 0 μm ;击射部位以距视盘 3DD处最佳  相似文献   
89.
目的探讨介入治疗急性肠系膜静脉血栓形成(AMVT)的方法及疗效。方法对15例经影像学确诊的AMVT患者进行了介入治疗,其中经肠系膜上动脉途径溶栓治疗8例,经皮经肝穿刺门静脉途径机械性取栓5例,经颈静脉经肝穿刺门静脉途径机械性取栓2例。结果15例患者均获成功,介入治疗后腹痛消失,血管造影可见肠系膜上静脉内血流通畅。本组均获随访,随访时间为10~22个月,均未复发。结论对于早期AMVT病例,介入治疗是一种较好的方法。  相似文献   
90.
Massive vascular malformation involving tongue can cause significant functional impairment. In this report we describe a rare case of extensive venous malformation involving tongue leading to obstructive sleep apnoea, inability to speak, eat, severe discomfort due to exposure induced dryness and ulceration. Multimodality treatment approach comprising of sclerotherapy, electrocautery and radiation therapy was used in this case.  相似文献   
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