超声诊断左肾静脉压迫综合征

目的:探讨超声诊断左肾静脉压迫综合征的临床价值。方法:对20例左肾静脉综合征患者用彩超在空腹状态下取平卧位、直立位和脊柱后伸位经上腹部横断面及纵断面测量左肾静脉（LRV）扩张部位与受压部位内径并计算其扩张倍数、肠系膜上动脉（SMA）与主动脉（AO）夹角角度。结果:平卧位时,患者LRV扩张倍数2.1～4.2倍,SMA与AO夹角角度10 89°～16.74°;直立位和脊柱后伸位时,LRV扩张倍数进一步增大、SMA与AO夹角角度则进一步变窄。结论:超声对左肾静脉压迫综合征的诊断准确、可重复性强,应作为首选检查方法之一。     

彩超诊断儿童左肾静脉压迫综合征2例

例1 患者,女,6岁.因血尿待查入院.超声所见:双肾形态正常,右肾大小约6.8cm×3.2cm,左肾大小约6.9cm×3.7cm;行上腹部平卧位横切可见肠系膜上动脉(SMA)与腹主动脉(AO)夹角的左侧左肾静脉(LKV)明显扩张,内径约0.7cm,CDFI显示血流信号充盈不饱满.夹角的右侧左肾静脉内径0.2cm,压迫部位血流信号缺失,呈典型的"胡桃夹"征(图1).彩超诊断:左肾静脉压迫综合征. 例2 患者,女,11岁.因无痛性肉眼血尿伴腰痛入院.超声所见:双肾形态饱满,右肾大小约10.6cm×3.9cm,左肾大小约11.3cm×4.8cm,实质回声略强,皮髓分界不清,集合系统无分离征象.上腹部横切,可见腹主动脉(AO)与肠系膜上动脉(SMA)之间左肾静脉受压,狭窄处内径0.2cm.CDFI显示受压处血流信号缺失(图2),其扩张段血流信号充盈不饱满,狭窄左侧左肾静脉明显增宽,内径0.8cm,呈"胡桃夹"现象.彩超诊断:     

精索静脉曲张患者中精索静脉及睾丸体积的超声分析

目的探讨彩色多普勒超声诊断精索静脉曲张患者中，双侧精索静脉之间及精索静脉曲张与睾丸体积改变之间的关系。方法采用彩色多普勒超声对30例正常人及73例精索静脉曲张患者的双侧精索静脉及睾丸体积进行检测，分析双侧精索静脉内径之间、患侧精索静脉内径与睾丸体积之间的相关性；回顾分析其中23例患者左侧精索静脉内径及左侧睾丸体积的变化。结果精索静脉曲张患者双侧精索静脉内径之间存在显著相关（P〈0．01），精索静脉曲张严重等级与睾丸体积无显著相关（P〉0．05），病程长短与睾丸体积变化存在显著相关（P〈0．05）。结论精索静脉曲张患者患侧精索静脉可影响对侧精索静脉；与睾丸体积变化密切相关的是病程的长短，而不是精索静脉曲张的严重程度；彩色多普勒超声检查有利于早期诊断及病情分析。     

实时超声诊断儿童直立性蛋白尿和非肾性血尿─—胡桃夹现象

在直立性蛋白尿和非肾性血尿的患儿中，应用实时超声检查出胡桃夹现象（左肾静脉压迫综合征）154例。其中男80例，女74例，年龄3～14岁。全部患儿于仰卧位发现左肾静脉（LRV）在肠系膜上动脉（SMA）和腹主动脉（AO）间均受压，扩张部位内径较狭窄部位宽2倍以上，脊柱后伸位站立20分钟后宽4倍以上，最宽者达15倍，同时SMA与AO间夹角变小。LRV扩张程度与其受压程度一致。本文强调各种不同体位对照检查，对确诊意义很大。文中探讨了超声诊断标准及发病机理，并认为超声诊断胡桃夹现象，是一项具有实用价值，值得推广的诊断方法。     

胡桃夹综合征误诊3例分析并文献复习

胡桃夹综合征（NCS）又称左肾静脉压迫综合征，是指左侧肾静脉（LRV）在腹主动脉（AO）与肠系膜上动脉（SMA）之间受压导致肾静脉高压、出现血尿或直立性蛋白尿、左侧精索静脉曲张和腰腹痛为主的一种少见病。我院收治院前曾误诊的3例结合文献复习如下。     

三种超声方法评价左肾静脉受压综合症的价值

目的探讨二维超声(2D)、彩色多普勒血流显像(CDFI)和脉冲多普勒(PD)诊断左肾静脉受压综合症(Nut-CrackerSyn-drome,简称NCS)的价值。方法应用PHILIPS公司生产的IU22及HDI5000彩色多普勒超声诊断仪检测临床出现血尿、蛋白尿,而肾功能正常的患儿50例。2D测量主动脉左侧左肾静脉扩张段内径(A)和主动脉前方左肾静脉受压段内径(B),计算A/B比值;CDFI观察左肾静脉扩张段和受压段彩色血流色差;PD测量左肾静脉扩张段流速(Va)和受压段流速(Vb)并计算Va/Vb比值。8例得到肾静脉造影证实,4例经增强CT证实,3例经MRI证实。结果15例得到其他影像学证实的患儿中,站立位2D诊断NCS12例,CDFI诊断NCS13例,PD诊断NCS12例。2D CDFI阳性例数为14例,2D PD阳性例数为14例,2D CDFI PD阳性例数为15。结论3种超声方法综合判断NCS可提高诊断符合率。     

超声诊断胡桃夹综合征1例

患者男 ,13岁。因反复发热、血尿 2月余 ,在外院诊断为肾炎治疗效果欠佳转入我院。查体 :肾区无叩痛。尿白细胞 0～ 5 / HP,红细胞 2 +/ HP,尿蛋白(+)。超声检查 :双肾未见异常。仰卧位 :肠系膜上动脉 (SMA)与腹主动脉 (AO)夹角间左侧左肾静脉内径 0 .6 cm;SMA与 AO夹角间右侧左肾静脉内径0 .2 cm。站立位 :SMA与 AO夹角间左侧左肾静脉内径 0 .7cm ;SMA与 AO夹角间右侧左肾静脉内径 0 .2cm。超声提示 :左肾静脉扩张 (考虑“胡桃夹”综合征 )见图 1。MRI:MIP成像显示 SMA与 AO之间夹角小于 4 5°,且压迫左肾静脉。 MRI意见 :…     

彩色多普勒超声对左肾静脉受压综合征的诊断价值

目的研究彩色多普勒超声诊断左肾静脉受压综合征的临床价值。方法运用彩色多普勒超声诊断左肾静脉受压综合征患儿32例，并与30例对照组儿童彩色多普勒超声调查结果进行比较，采用相关系数及U检验进行评估，从而提供客观诊断依据和方法，并指出不足。结果①SMA与AO夹角与LRV近肾门端流速显著相关，夹角越小，流速越慢。LRV流速与LRV内径b／a值极显著相关，b／a值越小，流速越慢。SMA与AO夹角与LRV的b／a值显著相关，夹角小，b／a值小。②正常儿童与患儿SMA与AO夹角二者统计值存在显著差异，正常儿童SMA与AO夹角平均值大于患者。③正常儿童与患儿的LRV流速具有统计学意义，前者的LRV流速显著大于后者。④提出受检者SMA与AO夹角、LRVMAXVEI．(m／s)及I．RV的b／a值三者变量测试正常控制范围。结论超声诊断左肾静脉受压综合征，对儿童不明原因血尿或蛋白尿具有重要诊断意义。     

彩色超声多普勒诊断18例胡桃夹综合征

胡桃夹综合征即左肾静脉压迫综合征又称胡桃夹现象,是由于先天性或后天因形体变化等原因造成的左肾静脉在经过肠系膜上动脉(SMA)和腹主动脉(AO)之间的夹角处受到挤压后,导致左肾静脉近端(靠近肾门处)扩张而引起的一系列综合征。彩色超声多普勒可以通过测量SMA和AO之间的夹角,通过脊柱后伸位试验前和试验后对左肾静脉受压处     

儿童精索静脉曲张1例

病例男，７岁，因下腹部不适前来我院就诊。心，脑，肺未见异常，遂行全身超声检查，在左侧阴囊根部可探及３．２cm×１．６cm中低回声光团，边界清（图１），其内变形、弯曲的条索状无回声暗区为曲张的精索静脉，数量明显增多，内径达４．２cm，彩色频谱示为静脉血流（图２，３），双侧睾丸均正常。超声提示：左侧精索静脉曲张。５天后手术证实。讨论精索静脉曲张多发生在左侧，右侧及双侧者少见，其主要原因为左侧精索内静脉垂直进入左肾静脉，而右侧精索内静脉斜行直接汇入下腔静脉。精索静脉曲张是不育症原因之一。①②③图１左侧阴囊根…     

Left Atrial- and Left Ventricular-Based Single Lead DDD Pacing

DE COCK, C.C., et al. : Left Atrial- and Left Ventricular-Based Single Lead DDD Pacing. Single lead physiological pacing with right ventricular apex stimulation is feasible in patients with normal sinus node function and is associated with lower costs and a reduced complication rate. Left ventricular or biventricular pacing using the tributaries of the coronary sinus was reported to improve functional status and quality-of-life in patients with advanced congestive heart failure and intraventricular conduction delays. In addition, the proximal part of the coronary sinus has been successfully used for left atrial stimulation. The feasibility and pacing characteristics of left atrial- and left ventricular-based temporary pacing using a conventional single pass lead were studied. The tip of the lead was advanced in a distal position of the lateral or posterolateral branches of the coronary sinus, providing a stable position of the middle and proximal electrode pair in the first 2–7 cm of the coronary sinus. A successful stable position was achieved in 13 of 21 consecutive attempts. Using overlapping biphasic (OLBI) stimulation, left atrial and left ventricular pacing threshold were  2.3 ± 0.6 and 2.5 ± 0.5 V  , respectively. Acceptable sensing values were measured for P waves (  4.1 ± 0.7 mV  ) and R waves (  9.7 ± 3.9 mV  ). There was a good correlation between the diameter of the coronary sinus as assessed by quantitative coronary angiography at the level of the middle and proximal rings and atrial pacing threshold (  r = 0.92, P < 0.0001  ). Thus, single lead left atrialand left ventricular-based pacing is feasible although further development is necessary to increase the success rate for stable stimulation at both sites.     

Left ventricular function

The Doppler indexes of tricuspid porcine bioprosthetic valves were evaluated in twelve patients without clinical and two-dimensional echocardiographic evidence of valve dysfunction. Peak and mean pressure gradients across the prostheses were measured using the simplified Bernoulli equation. All the Doppler measurements were compared during inspiration and expiration. During inspiration peak velocity, peak gradient and mean gradient (1.52 ± 0.28 m/s; 9.7 ± 3.05 mmHg; 4.07 ± 1.16 mmHg) were significantly higher than during expiration (1.28 ± 0.8 m/s; 6.58 ± 2.7 mmHg; 2.98 ± 1.13 mmHg; p < 0.01) but pressure half time was not significantly different (122 ± 62 ms versus 134 ± 75 ms; p > 0.05). Inspiratory range of peak velocities, peak gradients, mean gradients and pressure half times were respectively 0.8–2.04 m/s; 4.9–16.6 mmHg; 1.2–7.2 mmHg; 42–340 ms while expiratory range of values was 0.8–1.93 m/s; 2.6–15 mmHg; 1.1–5.7 mmHg; 46–345 ms. These data suggest that even very long pressure half times do not indicate valve dysfunction. This study demonstrates that large variation of Doppler parameters are present during respiration and could produce inaccuracy in the assessment of bioprostheses in tricuspid position if they are not taken in consideration.