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51.
Magnetic resonance imaging of the craniocervical junction 总被引:1,自引:0,他引:1
Robert Lufkin Fernando Vininuela John R. Bentson Jacques E. Dion 《Computerized medical imaging and graphics》1988,12(5):281-292
Magnetic resonance imaging has become the study of choice for the majority of abnormalities of the craniocervical junction as well as for demonstration of primary pathology of the spinal cord, and brain stem. Although the applications of MR are currently limited by its high cost, relatively long scan time, and low sensitivity to calcification, new pulse sequences, faster scan strategies, and lower cost MR scanner are changing this situation. MR contrast agents and the use of 3-D imaging techniques combined with gradient echoes promise to play a role in MR of the craniocervical junction in the near future. 相似文献
52.
Rainer Pankau Carl-Joachim Partsch Johannes Funda Wolfgang Günther Sippell 《American journal of medical genetics. Part A》1992,43(3):513-516
We report on the hypothalamic-pituitary-gonadal function in 2 male infants with the Smith-Lemli-Opitz (SLO or RSH) syndrome. Both infants had abnormal external genitalia. Basal and LHRH stimulated plasma gonadotropins were normal for age (1 month). Plasma testosterone, androstenedione, and dehydroepiandrosterone sulfate were normal for age and sex. Some forms of congenital adrenal hyperplasia (17,20-desmolase deficiency, 17α-hydroxylase deficiency, and 3β-hydroxysteroid dehydrogenase deficiency) were ruled out by hormonal studies. The endocrinological findings indicate a normal hypothalamic-pituitary-gonadal function and a normal adrenal steroid biosynthesis in these 2 patients. A partial androgen receptor defect causing the genital malformations seems possible in one patient. Whether 5α-reductase deficiency is the cause of the male pseudohermaphroditism in SLO syndrome remains the subject of future studies. © 1992 Wiley-Liss, Inc. 相似文献
53.
Summary A pathologic study was undertaken of seven encephalic arteriovenous malformations, including five resected from one to seven days after balloon embolization, one resected 10 days after embolization with polyvinyl alcohol foam (PVA), and a large mesencephalic AVM in a patient who died eight weeks after a series of embolization procedures with PVA and silicone spheres. AVM's resected 6–7 days following balloon embolization showed focal mural and adventitial inflammatory infiltrates and parenchymal (i.e. non-vascular) necrosis of a large portion of one AVM. The AVM examined 7 days post-balloon embolization showed an intraluminal thrombus containing refractile particles surrounded by foreign body giant cells (FBGC's). The AVM removed 10 days after PVA embolotherapy showed mural and perivascular necrosis with infiltration by polymorphonuclear leukocytes. The single autopsy case showed FBGC's surrounding residual PVA, refractile particles deep within vascular walls, and marked mural thickening of AVM channel walls, changes that may represent a response to previous angionecrosis and inflammation at the time of embolization. These findings, the pathogenesis of which is discussed in detail, may help to explain some of the rare complications of iatrogenic embolotherapy with these materials, as well as providing evidence for the basis of their efficacy.Presented in part at the 63rd Annual meeting of the American Association of Neuropathologists, Seattle, Washington, June, 1987 相似文献
54.
55.
目的研究可控性丝线的致栓效果及其治疗体表难治性海绵状静脉畸形的初步疗效。方法将丝线一端留置于不同管腔大小的静脉内,另一端挂于血管壁埋于皮下,实现其可控性,用经过不同处置的丝线,分别留置于兔耳缘静脉、股静脉,观察其引起血管栓塞的效果。选择致栓效果较好的丝线组,用于临床治疗难治性体表海绵状静脉畸形的患者。结果几种经不同处置的丝线,均能不同程度地起到闭塞血管的作用,对于管腔稍大,血流较快的静脉(兔股静脉),浸泡丝裂霉素并打结的丝线组,致栓效果最好;临床初步应用证实,可控性丝线治疗体表难治性静脉畸形,安全有效。结论可控性丝线静脉内留置术,是一种安全、有效、损伤小、操作简便的治疗体表难治性海绵状静脉畸形的新方法。 相似文献
56.
Arteriovenous malformation of the foot is very uncommon, and surgical closure after its treatment with embolization and total excision may be challenging for the foot surgeon, particularly in distally localized lesions. A popular method to cover these difficult wounds is free-tissue transfer, which is a highly demanding procedure. Alternatively, distally based regional flaps have been occasionally reported for clinical use in such distant foot defects. Herein, we present a 36-year-old female patient with a diagnosis of arteriovenous malformation arising in the distal medial plantar and dorsal surfaces of the right foot. After surgical resection of the vascular lesion preceded by a misapplied embolization procedure, an extended lateral supramalleolar flap was successfully transferred to the defect area, covering it completely. Functional and aesthetic outcome was satisfactory after 6 months follow-up. Extended lateral supramalleolar flap is a useful and reliable choice for distal foot reconstructions. 相似文献
57.
目的用易获得的化学药物建立大鼠四肢畸形发生率稳定、畸形类型特异的动物模型。方法采用抗肿瘤类致畸药物白消安作为受试物,观察不同剂量和不同给药时间的胎仔畸形率、畸形类型及特征。结果在大鼠受孕第12天(GD12),一次经口给予白消安25mg/kg时,胎仔畸形类型主要为肢体畸形。肢体畸形率以活胎计为37.9%(33/87),以窝计为61.5%(8/13)。畸形类型常见于多指(趾)和缺指(趾),掌跖骨缺失和骨化不全发生率也较高。此外,还发生胫骨缺失和骨化不全,在观察大体形态时所见的短肢是由胫腓骨缺失和发育不全所致。四肢畸形的发生率和严重程度存在着不对称性,后肢较前肢出现率高,缺指(趾)畸形较其他畸形出现率高。结论成功建立大鼠肢体畸形动物模型,为进一步分析研究肢体发育畸形的分子机制和潜在原因奠定了基础。 相似文献
58.
目的 探讨磁共振成像各种方法对脑静脉畸形的诊断价值。方法 收集本院6例脑静脉畸形病例,均进行过磁共振T1WI、T2WI扫描,其中部分病例做过DWI、T2FLAIR、MRA、MRV、T1WI增强扫描及DSA。结果 幕上4例,幕下2例,T1WI、T2WI表现:引流静脉均为流空的低信号,深髓静脉为细条状长T1、长T2信号。其中1例DWI引流静脉及深髓静脉区域低信号;1例T2 FLAIR引流静脉流空的低信号,深髓静脉高信号;2例MRA均阴性,但MRV显示深髓静脉汇入引流静脉;2例T1 WI增强扫描:深髓静脉呈轮辐状汇入引流静脉;1例DSA:动脉期阴性,静脉期见典型的“海蛇头”征。结论 磁共振能明确诊断脑静脉畸形,T1WI增强扫描及MRV均较敏感,DSA为诊断脑静脉畸形金标准。 相似文献
59.
婴儿主动脉缩窄合并心内畸形的一期矫治 总被引:3,自引:2,他引:1
目的总结婴儿主动脉缩窄(CoA)合并心内畸形一期矫治的手术方法和临床经验。方法2001年1月至2006年1月,对28例CoA合并心内畸形患者行一期手术矫治。CoA为导管前型18例,邻近或正对导管处10例;伴主动脉弓发育不良6例,动脉导管未闭22例。合并的心内畸形包括:室间隔缺损16例、室间隔缺损+房间隔缺损5例、完全性房室间隔缺损3例,完全型大动脉错位伴室间隔缺损(D—TGA/VSD)2例,右心室双出口2例。采用左胸后外侧联合胸骨正中切口(双切口)径路手术12例,胸骨正中切口径路(单一切口)手术16例。采用缩窄段切除端端吻合术20例,Gore—Tex补片扩大成形术4例,左锁骨下动脉翻转扩大成形术4例。结果全组无手术死亡,术后呼吸机辅助呼吸时间7h~13d,住ICU时间3~18d。因术后心脏扩大延迟48~72h关胸4例,术后发生急性肾功能衰竭行腹膜透析3例,吸入一氧化氮(NO)治疗重度肺动脉高压3例。术后下肢收缩压高于上肢10~20mmHg18例(64.3%),收缩压上、下肢相差不大8例(28.6%),上肢分别高于下肢15mmHg和20mmHg2例(7.1%)。所有患者均得到随访,随访时间3~50个月,1例D—TGA/VSD患者因重度三尖瓣反流、肺部严重感染和呼吸功能衰竭于术后3个月死亡;其余27例患者恢复顺利。心脏超声心动图提示:1例采用端端吻合法、1例采用Gore~Tex补片扩大成形术的患者在CoA纠治处仍存在压差,分别为25mmHg、28mmHg,均未再次手术。结论一期手术矫治CoA合并心内畸形可以缩短疗程,有利于患者术后心、肺功能的恢复,避免二次手术的痛苦,降低治疗费用。可采用单一胸骨正中切口或胸骨正中联合左胸后外侧切口完成手术。 相似文献
60.
抗心磷脂抗体与脑血管病关系的研究 总被引:2,自引:0,他引:2
目的:探讨抗心磷脂抗体(aCL)与脑血管病(CVD)的关系。方法:检测266例缺血性脑血管病(ICVD)患者和73例脑出血(CH)患者血清aCL。结果:ICVD患者aCL阳性率高于对照组(P<0.01),且IgG型aCL比IgM型aCL阳性率升高(P<0.01)。CH患者aCL阳性率高于对照组(P<0.01)。ICVD组aCL阳性率与CH组比较无显著性差异(P>0.05),ICVD组、CH组和对照组不同性别间aCL阳性率无显著性差异(P>0.05)。结论:aCL可作为CVD危险性增加的指标,对CVD的预测有一定意义,包括ICVD和CH患者,aCL阳性率男女性别之间无差异。 相似文献