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101.
Dan Greitz 《Child's nervous system》2007,23(5):487-489
Objective This study aims to question the generally accepted cerebrospinal fluid (CSF) bulk flow theory suggesting that the CSF is exclusively
absorbed by the arachnoid villi and that the cause of hydrocephalus is a CSF absorption deficit. In addition, this study aims
to briefly describe the new hydrodynamic concept of hydrocephalus and the rationale for endoscopic third ventriculostomy (ETV)
in communicating hydrocephalus.
Critique The bulk flow theory has proven incapable of explaining the pivotal mechanisms behind communicating hydrocephalus. Thus, the
theory is unable to explain why the ventricles enlarge, why the CSF pressure remains normal and why some patients improve
after ETV.
Hydrodynamic concept of hydrocephalus Communicating hydrocephalus is caused by decreased intracranial compliance increasing the systolic pressure transmission into
the brain parenchyma. The increased systolic pressure in the brain distends the brain towards the skull and simultaneously
compresses the periventricular region of the brain against the ventricles. The final result is the predominant enlargement
of the ventricles and narrowing of the subarachnoid space. The ETV reduces the increased systolic pressure in the brain simply
by venting ventricular CSF through the stoma. The patent aqueduct in communicating hydrocephalus is too narrow to vent the
CSF sufficiently. 相似文献
102.
Francisco Jose Martinez-Guijarro Eduardo Soriano Jose Antonio del Rio Carlos Lopez-Garcia 《Brain research》1991,547(2)
An antibody against the calcium binding protein parvalbumin selectively labels a set of neurons in the cerebral cortex of lizards. Golgi-like immunostained bipolar, multipolar and pyramid-like neurons appear mainly located in the inner plexiform layers. Parvalbumin-immunoreactive (PARV-IR) puncta are concentrated in the cell layer of the dorsal and dorsomedial cortices showing a basket-like distribution. The morphology and distribution of PARV-IR neurons and puncta overlap GABA-immunostaining in the cerebral cortex of lizards. Thus, it is likely that PARV-IR neurons are a subset of the cortical GABAergic neurons of lizards. 相似文献
103.
Effect of the free radical scavenger MCI-186 on spinal cord reperfusion after transient ischemia in the rabbit 总被引:4,自引:0,他引:4
Kenichi Hashizume Toshihiko Ueda Hideyuki Shimizu Atsuo Mori Ryohei Yozu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(8):426-433
Objective: Paraplegia remains a serious complication of aortic operations. The production of free radicals during reperfusion
after transient ischemia is believed to induce secondary spinal neuronal injury, resulting in paraplegia. The aim of the present
study was to clarify the protective effect and method of administration of antioxidants on the neurological and histological
outcome in the animal model for reperfusion injury after transient spinal cord ischemia. Methods: New Zealand white rabbits underwent surgical exposure of the abdominal aorta that was clamped for 15 minutes to achieve spinal
cord ischemia. Group A animals received two 10 mg/kg doses of 3-methyl-l-phenyl-2-pyrazolin-5-one (MCI-186) at the time of
release of the aortic clamp and 30 minutes later. In group B, MCI-186, 5 mg/kg, was given three times, at the time of aorta
clamp release, 30 minutes and 12 hours later. In group C (control group), one dose of vehicle was administered. Neurological
status was assessed using modified Tarlov’s score until 168 hours after operation. Spinal cord sections were examined microscopically
to determine the extent of ischemic neuronal damage. Results: Groups A and B animals had better neurological function than group C (p(0.001). In contrast, group C animals exhibited paraplegia or paraparesis with marked neuronal necrosis. The number of surviving
neurons within examined sections of the spinal cord was significantly greater in group B than in group C (p(0.001). Conclusion: In a 15-minute ischemia-reperfusion model using rabbits, systemic repetitious administration of MCI-186, a free radical scavenger,
was found to have a protective effect on the spinal cord neurons both neurologically and histologically. We postulate that
the drug minimizes the delayed neuronal cell death for reperfusion injury after transient ischemia by reducing the free radical
molecules. Moreover, it was thought that we could protect delayed neuronal cell death more effectively by administering MCI-18612
hours later. 相似文献
104.
105.
106.
Choroid plexus papillomas (CPPs) are typically considered as benign tumors, with a favorable long-term prognosis. Drop metastasis of CPP into the spinal subarachnoid space is rare. We report a 42-year-old woman who presented with headache and back pain 6 years after removal of a posterior fossa CPP. Magnetic resonance imaging revealed mass lesions in the lumbosacral subarachnoid space and recurrent intracranial tumor. The lesions were resected and histologically diagnosed was CPP. We consider that CPP can spread via cerebrospinal fluid pathways and cause spinal drop metastasis. Therefore, it is necessary to evaluate the whole spinal axis and to perform periodic follow-up examinations in patients with CPP. 相似文献
107.
同时应用融合和非融合技术治疗创伤性腰椎间盘损伤(附4例临床病例报道及文献复习) 总被引:3,自引:1,他引:2
目的观察同时应用融合及非融合技术治疗腰椎间盘损伤的远期疗效,对照该术式与非手术治疗的远期疗效。方法对4例由于急性外伤引起的L4/L5及L5/S1椎间盘损伤患者进行影像学评价。根据生物力学稳定性对病变节段分别采用融合和非融合技术。手术全部经前路腹膜外切口。L5/S1采用椎间融合(自体髂骨 cage植入),L4/L5采用人工椎间盘植入。术后随访4年,摄术后X线正侧位、动力位片,术后2年MRI检查,SF36问卷调查。同期8例患者采用非手术治疗作为对照。结果术后6、12、24、36及48个月X线片显示,融合节段正侧位椎体间无移位,全部患者均有明显的骨性融合。非融合节段人工椎间盘假体位置良好,术后2年MRI显示有正常活动。同期8例非手术治疗患者5例缓解,3例因症状加重实施手术。结论前路融合技术可以有效稳定椎节,缓解腰椎不稳所致的疼痛。人工腰椎间盘植入可以有效地维持放射学稳定性,但不能完全替代正常椎间盘的功能。 相似文献
108.
颅咽管瘤全切除术后钠代谢紊乱及处理 总被引:26,自引:5,他引:21
目的分析颅咽管瘤全切除术后钠代谢紊乱的病理生理、诊断及处理。方法对我科86例巨大颅咽管瘤(直径>3.5cm)全切除患者进行回顾性分析,根据血钠、尿钠、渗透压以及中心静脉压等确定钠代谢紊乱类型,并进行相应处理。结果发生低钠血症29例(33.7%,29/86)、高钠血症13例(15.1%,13/86)、高钠及低钠血症交替9例(10.5%,9/86)。高钠及低钠血症平均开始时间分别为术后(2.3±0.7)d和(4.8±1.6)d。2例死于严重下丘脑反应,其余钠代谢紊乱均纠正良好,平均住院时间26 d。结论钠代谢紊乱是颅咽管瘤全切除术后常见表现之一。高钠血症与尿崩症关系密切,而低钠血症主要有两个原因:脑性盐耗综合征和抗利尿激素不适当分泌综合征,二者要仔细区分,前者着重补液、补盐,而后者应在补盐的基础上要适当限水和利尿。 相似文献
109.
Objective To establish a means for prenatal prediction of spinal muscular atrophy (SMA) through survival motor neuron (SMN) gene deletion analysis and genetic counseling in families with a child affected with SMA.
Methods Genetic analysis for prenatal prediction of Werdnig-Hoffmann disease was performed in a at risk Chinese family by polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) in SMN gene exons 7 and 8.
Results The pregnancy was positive for the homozygous deletion of the SMN gene, thus the fetus was diagnosed as being affected and the pregnancy was terminated.
Conclusion This approach is fast and reliable for DNA-based prenatal diagnosis of Werdnig-Hoffmann disease. 相似文献
Methods Genetic analysis for prenatal prediction of Werdnig-Hoffmann disease was performed in a at risk Chinese family by polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) in SMN gene exons 7 and 8.
Results The pregnancy was positive for the homozygous deletion of the SMN gene, thus the fetus was diagnosed as being affected and the pregnancy was terminated.
Conclusion This approach is fast and reliable for DNA-based prenatal diagnosis of Werdnig-Hoffmann disease. 相似文献
110.
腰麻硬膜外联合麻醉在全产程中的镇痛效果及对母婴的影响 总被引:12,自引:0,他引:12
①目的 探讨腰麻硬膜外联合麻醉在全产程中的镇痛效果以及对母婴的影响。②方法 选择ASAⅠ~Ⅱ级、无禁忌证的单胎头位临产初产妇 30 0例 ,随机分为腰硬组 (腰麻硬膜外联合麻醉 )、硬外组 (硬膜外麻醉 )和对照组 (未用任何麻醉方法 )各 10 0例。行L2~ 3 椎间隙一点穿刺并一次成功。分别观察镇痛效果、起效时间、用药量、副作用、产程、分娩方式及母婴情况。③结果 腰硬组镇痛效果、起效时间以及用药量明显优于硬外组(uc=5 .34,t=16 .92~ 2 9.6 9,P <0 .0 1) ;与对照组比较 ,宫颈扩张加速 ,第一产程明显缩短 ,而第二产程延长 (t =3.34~ 4 8.4 9,P <0 .0 1) ,剖宫产率明显下降 ,而阴道助产率增高 ,胎儿宫内窘迫的发生率下降 (χ2 =6 .82~ 2 0 .35 ,P <0 .0 1)。④结论 腰麻硬膜外联合麻醉用于分娩镇痛优于硬膜外麻醉 ,是一种安全有效、更适合全产程镇痛的麻醉方法。 相似文献