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71.
目的 探讨脑动静脉畸形相关的供血动脉远端破裂动脉瘤的特点与血管内治疗方法.方法 11例以自发性蛛网膜下腔出血发病的患者均接受数字减影血管造影,并被证实出血来源于脑动静脉畸形供血动脉远端破裂动脉瘤.根据动脉瘤的形态和供血动脉特点,选择以弹簧圈闭塞动脉瘤和载瘤动脉,或以高浓度生物胶栓塞动脉瘤和载瘤动脉.结果 11例栓塞后的动脉瘤均消失,未发生再出血,以弹簧圈栓塞的7例术后未发生新的神经系统症状;以生物胶栓塞的4例有2例术后发生栓塞部位的脑梗死.结论 脑动静脉畸形供血动脉远端动脉瘤破裂后血管内栓塞治疗可取得较好的效果,首选以弹簧圈栓塞动脉瘤和载瘤动脉,也可用高浓度生物胶栓塞,动静脉畸形可择期再处理. 相似文献
72.
结构蛋白及血管形成因子在体表海绵状静脉畸形中的表达及意义 总被引:3,自引:0,他引:3
目的:研究结构蛋白及血管形成因子(VEGF)在体表海绵状静脉畸形(cavernous venous malformation,CVM)中的表达及意义。方法:1996-2000年CVM病理样本25例,取正常中、小型静脉各12例。采用Envision法免疫组化染色观察Ⅳ型胶原、纤维连接蛋白(Fn)、层粘连蛋白(Ln)及VEGF、血管生成素-1(Ang-1)等血管形成因子的表达,半定量分析结果。结果:Ⅳ型胶原、Fn和Ln在海绵状静脉畸形与中、小静脉中的分类似,但表达量明显较少。畸形组织和小静脉VEGF表达明显强于中型静脉,小静脉Ang-1表达明显强于静脉畸形和中型静脉。结论:Ln及VEGF表达变化可能是海绵状静脉畸形形成发展的重要因素。Ang-1表达减少可能参与海绵状静脉畸形的血管塑形障碍的发生。 相似文献
73.
目的探讨硬脊膜动静脉瘘(SDAVF)的病因、发病机制、临床表现、诊断及治疗。方法回顾性分析了1例患者的相关临床资料。结果本例患者以双下肢渐进性麻木、无力1年余,加重伴大小便障碍9个月为主要临床表现,脊髓MRI显示T9~L1髓内以长T2长T1为主之异常信号,超选择DSA造影可见位于入LT12椎管处一硬脊膜动静脉之瘘口,成功地进行了经单侧椎板开窗夹闭瘘口术。结论SDAVF为一具有直接的动静脉交通性病变,常伴有小型畸形团,多发生于中年男性,误诊率高,主要表现为渐进性的肢体麻木、无力及大小便障碍,MRI有助于诊断,但仍须DSA确诊。阻断连接瘘口与冠状静脉丛的引流静脉是治疗SDAVF的有效方法,显微外科手术效果可靠、复发率低,尽早地确诊和治疗是取得良好疗效的根本前提。 相似文献
74.
We report herein the cases of two infants who developed right pneumonectomy syndrome, both of whom were born with gross C-type esophageal atresia (EA/TEF), and a hypoplastic right lung arising from the lower esophagus, being a bronchopulmonary foregut malformation (BPFM). Appropriate and well-timed treatments for a variety of sequelae primarily caused by the mediastinal shift must be considered after right pneumonectomy in early childhood. 相似文献
75.
Rawatmal B. Surana Syed K. Rafi Kevi L. Christopher Thomas J. Reid Raymond B. Weiss 《Clinical genetics》1995,47(6):321-323
An apparently balanced de novo reciprocal translocation t(5;21) (q13;q22) was demonstrated in a girl with acrobrachycephaly, ventriculomegaly, pulmonary stenosis and anal malformation. The possible relationships between her karyotype and malformations are discussed. 相似文献
76.
W. J. Spitzer 《Der Radiologe》1996,36(3):188-192
Summary
Two-dimensional conventional X-rays and computer tomographic imaging systems contribute to the diagnosis and surgical planning
of patients with orofacial malformations. The ability to reformat CT scans into three-dimensional osseous and soft tissue
surface images has a significant impact on the diagnosis and management of orofacial malformations. Cephalometric evaluation
with teleradiography provides precise insight into both the skeletal structures and the soft parts, enabling the radiologist
to assess the relationship among the different parts in a given subject, at any given time and in relation to the normal.
相似文献
77.
一期动静脉转流与并加压破坏深静脉瓣对比的实验研究 总被引:1,自引:0,他引:1
目的:改进一期动静脉转流术的疗效。方法:10只狗双后肢,随机选择一侧后肢行一期动静脉转流,另一侧行一期动静脉转流加水压破坏深静脉瓣。术后30天通过动脉造影进行对比研究。结果:后者能更有效地加速远段深静脉瓣的破坏,使动脉血逆行更远,同时形成更为丰富的侧枝循环,而不会增加肢体肿胀和深静脉血栓的机会。结论:一期动静脉转流加水压破坏深静脉瓣可能是治疗严重肢体缺血更为有效的方法。 相似文献
78.
Women's life situation and experiences during pregnancy were prospectively studied in relationship to the development of congenital malformations (CMs) in their offspring, within samples of 84 offspring of pregnant index women with a history of nonorganic psychosis and 100 offspring of pregnant control women. Within both samples, offspring CMs were related to more problematic maternal life situations during pregnancy, the common denominator in these problems across samples being difficulties associated with the husband. Little relationship was found between CMs and the woman's own attitude toward the pregnancy or her mental condition during pregnancy. In both groups, total life situational problems and distress were more strongly related to the development of very minor CMs (termed "variants") than to the major, classical CMs. 相似文献
79.
N. Hirabuki T. Miura M. Mitomo K. Harada T. Hashimoto R. Kawai T. Kozuka 《Neuroradiology》1988,30(5):390-394
Summary Four patients with dural arteriovenous malformation (AVMs) draining into the cavernous sinus, who presented ophthalmic manifestations, were studied by magnetic resonance (MR) imaging. In all patients signal decrease in the involved cavernous sinus was demonstrated in coronal spinecho (SE) imaging. It is attributable to rapid venous flow in the sinus, and this high velocity signal loss is a fairly pathognomonic finding in this condition. We stress the validity of MR imaging in the primary diagnosis of dural AVMs with ophthalmic symptoms. 相似文献
80.
Intimal hyperplasia and hemodynamic factors in arterial bypass and arteriovenous grafts: a review 总被引:3,自引:0,他引:3
Stenosis at the graft–vein junction caused by intimal hyperplasia (IH) is the major cause of failure of vascular access grafts used for hemodialysis. There is a strong relationship between hemodynamic factors and formation of IH. The hemodynamic pattern and the location of IH are different in arterial bypass grafts (ABGs) compared with arteriovenous grafts (AVGs). In an ABG, end-to-side anastomosis of the expanded polytetrafluoroethylene graft and artery produces hemodynamic changes around the junction. IH develops at the arterial floor and the toe and heel of the distal anastomosis. Low shear stress and oscillating shear forces at the arterial floor and the heel plus a high wall sheer stress (WSS) gradient at the toe probably promote IH development. Compliance mismatch between the graft and artery causes turbulence that may contribute to IH formation. The blood flow rate in AVGs is 5–10 times greater than that in ABGs. High flow causes turbulence that injures endothelial cells and eventually results in IH. The peak WSS in AVGs is about 6N/m2, much higher than that in ABGs. Excessively high WSS may effect IH formation in AVGs. Several venous cuff or patch anastomotic designs have been used in attempts to regulate hemodynamic factors in grafts. In ABGs, these designs appear to help decrease IH formation. In AVGs, however, they generally have not improved patency rates. In a high-flow system such as an AVG, more drastic changes in anastomotic design may be required. 相似文献