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81.
Summary The cytoarchitectonics of the cerebral unlayered polymicrogyria located at the borders of a bilateral porencephalic defect is characterized by minute convolutions not exteriorized by sulci, in which blood vessels and increased numbers of fibrillary astrocytes are present in the fused molecular layers. The cellular organization, based on the analysis of Golgi sections, differs among gyral, intermediate, and sulcal regions and represents variable degree of cellular damage and structural organization of the cerebral mantle injured approximately in gestational month 5. Polymicrogyria may be produced by incomplete ischemia of radial territories vascularized by cortical blood vessels penetrating at right angles from the surface which is the result of the imbalance between the impaired cerebral blood flow of occluded large prerolandic arteries, responsible for the porencephalic defect, and the arterial meningeal anastomoses.Abnormal folding in polymicrogyria may be generated by lateral differences in the cortical thickness of adjoining areas, and by the imbalance in growth rates of laterally contiguous cortical regions.Dedicated to A. Gonzalez  相似文献   
82.
目的 :探讨孕妇弓形虫感染对胎儿的影响。方法 :采用酶免三联诊断法对 35 6例母婴配对标本进行血清学检测。结果 :产妇弓形虫感染率平均为 19 1% ,各单项检测分别为循环抗原 (CAg) 15 2 %、IgM2 5 %、IgG3 4% ;新生儿弓形虫感染率平均为 17 7% ,其脐血各单项检测分别为CAg16 9%、IgM0 3%、IgG2 2 %。CAg垂直传播率为 35 2 % ( 19/5 4)。 4例畸胎儿中 1例脐血弓形虫CAg阳性。结论 :孕妇感染弓形虫可通过胎盘垂直感染胎儿 ,应引起围产医务工作者的高度重视 ,加强对弓形虫感染的早期诊断和及时治疗  相似文献   
83.
《Neuro-Chirurgie》2021,67(2):132-139
BackgroundMicro-arteriovenous malformations (micro-AVMs) are defined as AVMs just visible on angiography with a nidus size between 0.5 and 1 cm. Their principal manifestation is intracranial hemorrhage and their diagnosis and therapeutic management are still unclear.MethodsThe aim of our work was to show the clinical presentation, treatment and outcome of ruptured cerebral micro-AVMs in a retrospective cohort study of 19 patients and a systematic review of the literature.ResultsWe obtained a total of 20 micro-AVMs in 19 patients. The mean age was 47.3 years. Clinical presentation was acute bleeding. The mean volume of hematoma was 12.9 mm3 (0 - 60.4), with topographic distribution as follows: 64% cortical with supratentorial bleeding, 26% deep, and 10% in the posterior fossa. Among the 20 micro-AVMs of the series, 11 (55%) had endovascular management, 6 (30%) had surgical treatment and 3 (15%) had GK radiosurgery alone. All of our patients have been cured at the end of the follow up without re-permeabilization. In our series, clinical outcome showed good recovery with a mean score of 4.6 on Glasgow Outcome Scale (GOS). In the literature, 88% of patients had a GOS of 4 or 5.DiscussionIntracerebral hematoma (ICH) was the main clinical manifestation. In the case of negative initial angiographic assessment, patients must have supraselective angiographic exploration. In the case of conservative treatment of hematoma, endovascular obliteration and microsurgical exclusion seems to be reasonable therapeutic options, according to our observations.  相似文献   
84.
Vaginal agenesis with anorectal malformations is a complex pediatric condition that adversely affects various physiological processes in the body. It may cause disturbances in defecation and urination, abnormalities in the urinary and gastrointestinal tract, dysfunction of the genital and reproductive organs, and sexual function disorders. The complexity in the surgical management of vaginal agenesis includes the selection of a functional reconstruction technique for anal and vaginal formation, timing of the reconstruction, and management of complications in the associated organ system.Herein, we describe a patient with Mayer–Rokitansky–Küster–Hauser syndrome accompanied by a rectovesical fistula. Other abnormalities, such as microcephaly, polydactyly, long urethral abnormalities resembling the male urethra, and complications in the kidney and urinary tract, were observed in the patient. The associated complications included recurrent urinary tract infections, urinary overflow incontinence, vesicoureteric reflux, hydroureter, and left renal hydronephrosis. The patient underwent posterior sagittal anorectoplasty surgery and vaginal reconstruction. The long-term vaginal physiological development of patients with this condition remains unknown.  相似文献   
85.
Summary The arterial and venous blood-supply of the intradural filum terminale was studied microscopically in 18 fresh cadavers after removing the dorsolumbar spinal cord in one piece, with the roots and the filum in their dural sheath. The arteries were examined after manual injection of the artery of the lumbar enlargement, while study of the veins was made without injection since their bluish-black color made them easily identifiable. After gross examination, each specimen was fixed and then sectioned at 12 different levels from the medullary conus to the bottom of the dural sac for histologic study. The distribution of the vascularization the filum terminale appeared constant. A single artery, the artery of the filum, arises from the termination of the anterior spinal axis, either by trifurcation or from the proximal part of one of the 2 branches of the anastomotic ansa of the conus. The artery travels in front of the filum, with rapidly diminishing caliber; rarely, it can be followed into the sacral canal. The vein of the filum travels in front of that structure but behind the artery, as in the cord; its caliber is uniform but varies from subject to subject. It traverses the dura below and continuous with the anterior spinal vein above. No vessels were found on the dorsal aspect of the filum. While the artery of the filum is of a caliber proportional to that of the filum and appears to be a nutrient vessel, the vein has a caliber unrelated to that of the filum and appears rather as an intradural drainage route continuous with the anterior spinal vein. Several cases of disease of the filum terminale confirm this anatomic appearance and also show that, because of the existing hyperpressure in the vein of the filum, the posterior spinal vein also shares in the drainage of the latter and that entire system may function in both ascending and descending directions.
La vascularisation normale du filum terminale intradural chez l'homme
Résumé La vascularisation artérielle et veineuse du filum terminale intradural a été étudiée sur 18 cadavres frais, sous microscope, après prélèvement en monobloc de la moelle épinière dorso-lombaire, des racines et du filum dans leur étui dural. L'examen des artères a été fait après injection manuelle de l'artère du renflement lombaire, tandis que l'étude des veines s'est faite sans injection compte tenu d'une coloration bleu-noir spontanée qui les rendent aisément identifiables. Après étude macroscopique, chaque pièce a été fixée, puis coupée à 12 niveaux différents depuis le cône médullaire jusqu'au fond du cul-de-sac dure-mérien, pour étude histologique. La distribution de la vascularisation du FT apparaît constante. Une artère unique, l'artère du FT, naît de la terminaison de l'axe spinal antérieur, soit par trifurcation, soit de la partie proximale d'une des 2 branches de l'anse anastomotique du cône. L'artère chemine devant le FT; son calibre diminue rapidement; rarement, elle a pu être suivie jusque dans le canal sacré. Une veine, la veine du FT, chemine en avant du FT mais en arrière de l'artère, comme au niveau médullaire. Son calibre est uniforme mais variable d'un sujet à l'autre. Elle traverse la dure-mère en bas; elle se continue avec la veine spinale antérieure en haut. Aucun vaisseau n'a été retrouvé à la face dorsale du FT. Si l'artère du FT a un calibre qui est proportionnel à celui du filum et apparaît comme un vaisseau nourricier, la veine a un calibre sans aucun rapport avec le volume de celui-ci et apparaît davantage comme une voie de drainage intradural en continuité avec la veine spinale antérieure. Quelques cas de pathologie du FT confirment cet aspect anatomique et montrent aussi qu'en raison de l'hyperpression veineuse régnant dans la veine du FT, la veine spinale postérieure participe également au drainage de celle-ci et que l'ensemble peut fonctionner dans les 2 sens ascendant ou descendant.
  相似文献   
86.
腔内血管技术在肝静脉回流障碍综合征治疗中的应用   总被引:2,自引:0,他引:2  
目的:探索一种简单、安全、有效的治疗肝静脉回流障碍(Budd-Chiari)综合征的新方法。方法:在11例肝静脉回流障碍综合征患中,应用经皮穿刺下腔静脉气囊扩张成形术治疗获得成功后,有9例患同时置入血管内支架。3例肝静脉完全闭塞在下腔静脉腔内治疗术成功后1周内行肠系膜上静脉-下腔静脉间人造血管“H”型分流术。结果:11例患,除1例在腔内治疗后出现轻度心功能不全表现外,无手术并发症,术后随访6-35个月,血管内支架通畅、无移位,分流血管无血栓栓塞,门脉高压症状明显缓解,患生活质量提高。结论:腔内血管技术是肝静脉回流障碍综合征的首选治疗方法。  相似文献   
87.
Conventionalintra arterialdigitalsubtractionangiography (DSA)usedtoberegardedasthegoldstandardfordiagnosisofintracranialarteriovenousmalformations(AVMs) Recently ,newtechniquesofneuroimagingandcomputerassistedthree dimensionalreconstructionmakeitpossible…  相似文献   
88.
先天性心脏病心脏停跳和不停跳下心内直视手术的临床分析   总被引:15,自引:5,他引:10  
目的 对比分析心脏停跳和不停跳心内直视手术治疗先天性心脏病心内畸形的疗效。方法 5 5 8例患者分别采用心脏停跳手术 2 31例 ,不停跳手术 32 7例。心脏不停跳心内直视手术仍常规建立体外循环 ,置左心房引流管 ,降温至 (32± 1)℃并维持 ,仅阻断上下腔静脉 ,不阻断主动脉 ,维持灌注压在 8kPa左右 ,心脏跳动下进行畸形矫正 ,方法同停跳下手术。结果 不停跳组早期死亡 7例 (死亡率 2 .14 % ) ,停跳组早期死亡 5例 (死亡率 2 .17% ) ,其余均痊愈出院 ,随访 3~ 2 3月 ,恢复良好。结论 心脏不停跳心内直视手术 ,是一种有效的心肌保护方法 ,并可简化操作 ,缩短体外循环时间  相似文献   
89.
Capillary malformations are slow-flow vascular malformations that affect the microcirculation including capillaries and post capillary venules and can be associated with growth differences. Specifically, the association of capillary malformations with undergrowth is a vastly understudied vascular syndrome with few reports of genetic causes including PIK3CA, GNAQ, and GNA11. Recently, a somatic pathogenic variant in AKT3 was identified in one child with a cutaneous vascular syndrome similar to cutis marmorata telangiectatica congenita, undergrowth, and no neurodevelopmental features. Here, we present a male patient with a capillary malformation and undergrowth due to a somatic pathogenic variant in AKT3 to confirm this association. It is essential to consider that mosaic pathogenic variants in AKT3 can cause a wide spectrum of disease. There is a need for future studies focusing on capillary malformations with undergrowth to understand the underlying mechanism.  相似文献   
90.
We report eight cases of vein of Galen aneurysmal malformation (VGAM) assoicated with a Chiari type I malformation. In four cases magnetic resonance imaging (MRI) or computed tomography performed in the neonatal period did not demonstrate the posterior fossa anomaly, which appeared on later scans. In the other cases the MRI was performed in infancy and the anomaly was already present. We compared the venous phases of the posterior fossa angiograms and the MRI in these patients. In all eight cases, the angiograms showed a reflux in the cerebellar veins, via the petrous vein, associated with a uni-or bilateral stenosis or thrombosis of the distal posterior dural sinuses. Furthermore, in two cases the posterior fossa returned to normal on MRI following endovascular treatment, while in three cases the herniation of the cerebellar tonsils decreased after the embolization. Tonsillar prolapse becomes irreversible when the venous outlet is incapable of taking the flow even when the VGAM has been treated adequately. In eight additional cases of VGAM for which MRI and angiogram studies were available and in which stenosis or thrombosis of posterior dural sinuses was present without tonsillar prolapse, no reflux into the cerebellar veins was shown. We suggest that the posterior fossa hydrovenous congestion is a result of inadequate venous drainage and that the tonsillar descent is reversible if adequate venous drainage is reconstituted following therapeutic embolization of the fistula. Tonsillar prolapse is not a consequence of mass or raised intraventricular pressure. Our observation suggests that in some other conditions, the Chiari I malformations may be secondary to early hydrovenous dysfunction of the posterior fossa.  相似文献   
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