自制鹭嘴式神经内镜鞘辅助神经内镜手术治疗高血压性脑室出血

目的 探讨自制鹭嘴式神经内镜鞘辅助神经内镜手术治疗高血压性脑室出血的疗效。方法 回顾性分析2013年1月至2018年1月收治的63例高血压性脑室出血的临床资料。在鹭嘴式神经内镜鞘辅助下神经内镜手术治疗21例（内镜组）,单纯脑室外引流术治疗42例（引流组）。结果 内镜组术后血肿清除<60%有1例,60%~90%有9例,>90%有11例;引流组术后血肿清除<60%有40例,60%~90%有1例,>90%有1例;内镜组血肿清除率明显优于引流组（P<0.01）。内镜组术后并发症发生率（4.76%,1/21）明显低于引流组（30.96%,13/42;P<0.05)。术后 6个月,内镜组预后良好率（85.71%,18/21;ADL分级Ⅰ~Ⅲ级）明显高于引流组（52.38%,22/2;P<0.05）。结论 对于高血压性脑室出血,自制鹭嘴式神经内镜鞘能扩大操作空间,可提高神经内镜手术血肿清除率,减少并发症,明显改善病人预后     

Application of finite-element analysis with optimisation to assess thein vivo non-linear myocardial material properties using echocardiographic imaging

An application of finite-element analysis with an optimisation technique to assess the myocardial material properties in diastasisin vivo is described. Using the data collected from an animal model, the three-dimensional geometry of the left ventricular chamber, at several times in diastole, was reconstructed. From the measurement of the ventricular chamber pressure during image acquisition, finite-element analysis was performed to predict the expansion during diastasis. Initially, by restricting the motion of the epicardial nodes and computing the reaction forces, an ‘equivalent pericardial pressure’ was determined and applied in subsequent analysis. The duration of diastasis was divided into three or four intervals and the analysis was performed at each interval to assess the material properties of the myocardium. Using such a step-wise linear approach, the non-linear material properties of the myocardium during passive expansion was determined. Our results demonstrated that the computed ‘equivalent pericardial pressure’ increased with and was smaller than the corresponding left ventricularchamber pressure. The passive myocardium exhibited a linear tangent modulus against chamber pressure relationship which is equivalent to an exponential stress/strain relationship, similar to those suggested byin vitro studies.     

The enhancement of catecholamine-induced Cl− current by cyclic GMP revealed using photolabile caged compounds in guinea-pig ventricular cells

Whole cell currents were recorded in single myocytes dissociated from guinea-pig ventricles, and caged compounds were loaded intracellularly through the patch electrodes. Flash photolysis of caged cyclic GMP (cGMP) increased the amplitudes of both catecholamine-induced Cl^– (I_Cl) and Ca²⁺ currents (I_Ca) which were pre-activated by submaximum doses of isoprenaline. Transient activation of I_Cl by photo-release of cyclic AMP (cAMP) showed a half decay time (t_1/2) of 16.7±1.4 sec (mean±S.E.M., n=14). This decay was markedly delayed by inhibiting phosphodiesterases using 3-isobutyl-1-methyl-xanthine (IBMX). The intracellular application of cGMP (10–50 M)also prolonged the decay of the I_Cl response to caged cAMP (t_1/2=38.0±7.1 sec, n=12). These findings strongly support the hypothesis that cGMP facilitates the-adrenergic response of ionic currents through the inhibition of phosphodiesterase in mammalian cardiac myocytes.     

Radionuclide assessment of left ventricular function during dobutamine infusion in patients with coronary artery disease: comparison with ergometer exercise

The effects of dobutamine on left ventricular function were assessed employing radionuclide ventriculography (RNV) in 7 normal subjects (Group 1) and 21 patients with coronary artery disease (Group 2). After routine bicycle ergometer exercise RNV, dobutamine infusion was started at 5 micrograms/kg/min and the dosage was increased by 5 micrograms/kg/min every 4 minutes to a total of 15 micrograms/kg/min. In Group 1, left ventricular ejection fraction (LVEF) increased by both ergometer exercise and dobutamine infusion. In Group 2, LVEF did not increase during exercise, but increased during dobutamine infusion without evidence of significant myocardial ischemia. Only 2 patients in Group 2 had new regional wall motion abnormality. Left ventricular end-diastolic volume (LVEDV) in Group 2 increased from 191 +/- 19 to 210 +/- 18 ml during ergometer exercise, but decreased from 193 +/- 18 to 153 +/- 19 ml during dobutamine infusion. Short-term low-dose infusion of dobutamine may be used in patients without evidence of significant myocardial ischemia, but probably cannot be substituted for exercise testing in patients with mild to moderate coronary artery disease.     

超声心动图对尿毒症患者肾移植术前后左心结构和功能的评价

目的探讨尿毒症患者肾移植术前、后的心脏形态与功能的变化。方法应用超声心动图测量126例尿毒症患者肾移植前、后1、3个月的左室结构及功能。结果术后3个月超声心动图检查,各心腔均有所缩小,室间隔和左室后壁厚度变薄,搏动幅度增加,左室收缩功能及舒张功能较移植术前明显改善,扩大的左心房、左心室较术前缩小。结论尿毒症患者肾移植术后,随着尿量增多及体内毒素的大量排出,左室结构及功能均得以明显改善。     

磁共振扩散张量成像(DTI)在诊断中枢神经系统疾病中的应用

目的评价磁共振扩散张量成像(DTI)在诊断中枢系统疾病中的用途。方法 86例临床证实的中枢神经系统疾病患者包括超急性及急性期脑梗死40例,脑肿瘤32例,脑白质疏松7例,多发性硬化4例,脑中毒3例以及作为正常对照的健康志愿者9例均经常规磁共振序列和DWI、DTI检查,对患侧和健侧大脑白质纤维束感兴趣区各向异性分数(FA)值进行定量分析,获得方向编码彩色(DEC)图和黑白各向异性(FA)图,扩散张量纤维束成像(DTI)显示脑白质纤维束走形方向、损伤、受压、移位等情况。结果健康组不同部位的脑白质的FA值不同,但大脑半球两侧的FA值差异无统计学意义。超急性(发病后小于6 h)脑梗死区白质FA值与对侧相比轻度增高或降低,急性期(发病后6～72 h)脑梗死区白质FA值显著减低,FA图为低信号,健侧脑白质为高信号,均有明显差别。良恶性脑肿瘤FA值仅在瘤周水肿区的比较中有统计学差异,FA图肿瘤实质为稍低信号,中心坏死及周围水肿表现为低信号。脑白质病变和正常对照组感兴趣区测量FA值,病变区FA值降低,两组差异有统计学意义。结论 DTI可无创且清晰地显示白质纤维束走行方向及分布情况,对诊断中枢神经系统病变有重要用途。     

胡桃夹综合征的多层螺旋CT检查和应用价值

目的：探讨多层螺旋CT（MSCT）在诊断胡桃夹综合征（NCS）中的应用价值。方法：分析30例NCS患者（病例组）和120例正常人（对照组）的MSCT影像资料。观察NCS左肾静脉（LRV）的MSCT表现及伴随征象;测量病例组和对照组的肠系膜上动脉（SMA）与腹主动脉（AA）的夹角、LRV中心层面处SMA与AA之间距离、LRV在夹角受压处的截面积（S1）和近肾端最宽处的截面积（S2）,并计算其比值（S2/S1）,进行统计学分析。结果：病例组中2例可见左肾增大,2例左肾灌注慢,7例清晰显示侧枝循环建立,30例均可见LRV呈＂漏斗样＂变。两组比较各测量数据差异有统计学意义（P〈0.05）。结论：MSCT检查能清晰显示LRV的形态、能精确测量各数值,直观地评估LRV的受压变窄程度,还可观察NCS的伴随征象,为诊断提供有力的证据。     

超声心动图估测左心室舒张期末容积指数对确定法洛四联症根治手术指征的对比研究

目的探索超声更好地评估左心室发育情况的新方法,为确定法洛四联症(TOF)一期根治手术指征提供可靠依据。资料与方法使用超声心动图,分别采用传统的M型、二维单平面Simpson法、三维超声(3DE)测量法估测38例TOF患者的左心室舒张期末容积指数(LVEDVI),按LVEDVI<30ml/m2和≥30ml/m2进行分组,分别比较其相应的术后情况(呼吸机维持时间、ICU监护时间),将三种方法LVEDVI估测值分组比较,探讨其对手术预后的作用。结果 4例病人术后因严重的低心排出量综合征死亡,其余34例手术患儿安全度过了手术期。在三维测量法估测值分组中,病人术后情况差异有统计学意义,其他两种方法估测值分组中的病人术后情况差异无统计学意义,三种方法LVEDVI估测值分组比较均有统计学意义。结论三维超声通过估测LVEDVI可以为确定TOF一期根治手术指征提供有效的参考依据。     

3.0T MR LAVA技术在肝硬化胃左静脉显示的应用价值

目的 用3.0TMR肝脏加速容积采集(liver acceleration volume acquisition,LAVA)技术显示胃左静脉(LGV),探讨LGV扩张程度与肝硬化损害程度的关系.资料与方法 对40例肝硬化患者及20名正常自愿者行上腹部检查,采用最大密度投影(MIP)对LGV显示,并测量其直径.结果 40例肝硬化患者及20名正常自愿者LGV显示清晰.Child-Pugh A级组及Child-Pugh B,C级组的LGV直径较正常组明显增宽(P<0.05);上消化道出血组较不出血组的LGV直径增宽,两者之间差异有统计学意义(P<0.05);肝硬化患者LGV直径≥6mm组比其直径＜6mm组上消化道出血的风险增大,差异有统计学意义(P<0.05).结论 应用LAVA技术可以清晰显示LGV;测量LGV的直径可以间接评估肝功能损害程度;LGV直径明显增宽是上消化道出血的风险因素,当LGV直径≥6mm,上消化道出血的风险性增加.     

Valor pronóstico de la tomografía computarizada en la tromboembolia pulmonar aguda

In addition to being the standard reference for the diagnosis of acute pulmonary thromboembolism, CT angiography of the pulmonary arteries can also provide valuable information about the patient's prognosis. Although which imaging findings are useful for prognosis remains controversial, signs of right ventricular dysfunction on CT are now included in clinical algorithms for the management of pulmonary thromboembolism. However, the optimal method for obtaining these measurements while maintaining a balance between the ease of use necessary to include their evaluation in our daily activity and the loss of precision in its predictive capacity remains to be determined. Moreover, other variables associated with pulmonary thromboembolism that often go unobserved can complement the prognostic information we can offer to clinicians. This review aims to clarify some of the more controversial aspects related to the prognostic value of CT in patients with pulmonary embolisms according to the available evidence. Knowing which variables are becoming more important in the prognosis, how to detect them, and why it is important to include them in our reports will help improve the management of patients with pulmonary embolism.