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1.
经研究表明颈外静脉的瓣膜、缩窄环、瓣膜窦及窦段静脉壁共同组成一个灵敏地、高强度地抗逆流装置。本文称之为瓣膜窦段并报道189段的尸体解剖和光镜观察结果;测定尸体、活体和手术中瓣膜窦段的抗逆流功能,表明颈外静脉适于用无瓣导管作脑积水等分流途径。初步探明颈外静脉怒张的原因和消除怒张的简便方法以及术前鉴定瓣膜窦段位置和功能的方法。对2例脑积水用无瓣导管作侧脑室颈外静脉分流取得初步疗效。 相似文献
2.
Dynamic aspects of expanding cava septi pellucidi et Vergae 总被引:2,自引:0,他引:2
Summary Two paediatric patients with expanding cysts of the cava Vergae et septi pellucidi are presented. In the first patient, consecutive CT scans showed agrowing cavum thought to be responsible for his dramatic increase in head circumference. In the other patient, the expanding cavum was discovered because a routine skull X-ray after minor head trauma revealed marked impressiones digitatae.Both patients were successfully treated with stereotactically placed internal shunts from the cysts via the lateral ventricle to the subarachnoid space. During this procedure, contrast medium was instilled, and the cysts were visualized on postoperative CT scans.Some dynamic aspects of such expanding cava are discussed. 相似文献
3.
4.
A technique for temporary ventricular drainage using a subcutaneous pouch is described for use in neonatal hydrocephalus after intraventricular hemorrhage. The advantages include continuous, valve-regulated ventricular decompression, no exposed tubing, avoidance of electrolyte imbalance and of the loss of CSF, obviation of the need for repeated tapping, and the ability to convert to a peritoneal shunt on an elective basis. 相似文献
5.
Tomoyuki TAKANO Masaki OHNO Tsunekazu YAMANO Morimi SHIMADA 《Congenital anomalies》1991,31(3):129-139
Abstract This study was undertaken to elucidate the pathogenesis of the hydrocephalus and aqueductal stenosis induced by intracerebral mumps virus inoculation in suckling hamsters.
Mild ventricular dilatation became apparent after 5 days of inoculation. Focal denuding of the ependymal layer and subsequent aqueductal stenosis were observed by 14 days after inoculation. The virus antigen was detected not only in the ependymal cells and choroid plexus, but also in some neurons in the cerebral cortex, hippocampus, midbrain and cerebellum. In the cerebral aqueduct, the orderly arrangement of the cilialy clusters was destroyed on the 5th day after inoculation. After 10 days, proliferation of GFAP positive cells was noticed around the cerebral aqueduct and subsequently caused aqueductal stenosis. In the advanced state of hydrocephalus, the cerebellum was displaced downward and showed an elongated, atrophic and sleevelike structure similar to the Arnold-Chiari malformation. It was suggested that the extensive damage of the ependymal cilia may account for early ventricular dilatation, and subsequent aqueductal stenosis with glial proliferation is the main cause of the advanced hydrocephalus. It has not yet been determined whether the mumps virus can pass through the human placenta or not. If it can, however, our results strongly suggest that mumps virus infection in the human fetus will cause congenital hydrocephalus. 相似文献
Mild ventricular dilatation became apparent after 5 days of inoculation. Focal denuding of the ependymal layer and subsequent aqueductal stenosis were observed by 14 days after inoculation. The virus antigen was detected not only in the ependymal cells and choroid plexus, but also in some neurons in the cerebral cortex, hippocampus, midbrain and cerebellum. In the cerebral aqueduct, the orderly arrangement of the cilialy clusters was destroyed on the 5th day after inoculation. After 10 days, proliferation of GFAP positive cells was noticed around the cerebral aqueduct and subsequently caused aqueductal stenosis. In the advanced state of hydrocephalus, the cerebellum was displaced downward and showed an elongated, atrophic and sleevelike structure similar to the Arnold-Chiari malformation. It was suggested that the extensive damage of the ependymal cilia may account for early ventricular dilatation, and subsequent aqueductal stenosis with glial proliferation is the main cause of the advanced hydrocephalus. It has not yet been determined whether the mumps virus can pass through the human placenta or not. If it can, however, our results strongly suggest that mumps virus infection in the human fetus will cause congenital hydrocephalus. 相似文献
6.
A. Larsson Ch. Jensen M. Bilting S. Ekholm H. Stephensen C. Wikkelsö 《Acta neurochirurgica》1992,117(1-2):15-22
Summary Thirteen patients with normal pressure hydrocephalus were operated upon with an externally manoeuvrable shunt system (Sophy SU8) in order to investigate its influence on clinical outcome, intracranial pressure and cranial CT parameters. The opening pressure was set at high at surgery and lowered stepwise at intervals of three months to medium and low. The clinical condition, intracranial pressure and cranial CT parameters were examined at the end of the 3 months interval on each pressure level.The patients improved within the first 3 months inspite of an unchanged mean intracranial pressure and remained in a stable clinical condition during the rest of the study period. The intracranial pressure was significantly reduced at 9 months. The ventricular index, Evans index, temporal horn and third ventricle width were reduced 3 months post-operatively and did not change significantly during the rest of the study. The pre-operative third ventricle width was correlated to high psychometric test results after shunt surgery. Reduction in ventricular index, Evans index and third ventricle width after surgery correlated to improvement in psychometric scoring.The clinical improvement after shunt surgery for normal pressure hydrocephalus is seen within 3 months and is independent of the adjusted valve pressure. 相似文献
7.
张玉 《兰州大学学报(医学版)》1998,24(2):51-52,57
目的:研究影响正压性脑积水分流手术效果的因素。方法:从NPH患者的病因、症状、颅内压。CSF蛋白含量、年龄、病程及腰椎穿刺放液试验等因素分析手术效果。结果:蛛网膜下脸出血、脑外伤、脑瘤术后所致的NPH手术效果好;临床以痴呆和步态不稳或痴呆和尿失禁为主要症状的手术效果好;腰穿放液试验有效、病程<6个月、年龄<60岁、颅内压波动易达到1.5kPa以上的手术效果好。CSF蛋白含量高易造成分流管堵塞,远期效果欠佳。结论:影响NPH手术疗效的因素复杂,综合分析各因素对判断手术效果有益。 相似文献
8.
Liana Beni-Adani Naresh Biani Liat Ben-Sirah Shlomi Constantini 《Child's nervous system》2006,22(12):1543-1563
Background and objective The classification of hydrocephalus in newborns and in infants is different from the classification in adulthood. This difference
exists due to disparity in the source pathologies that produce the hydrocephalus, and the practical distinctions in prognosis
and treatment choices. The objective of this paper is to present the spectrum of obstructive-communicating hydrocephalus,
which is more complex in the pediatric group, and to propose the relevance of this particular classification to treatment
options.
Materials and methods The authors categorized infants with active hydrocephalus at time of presentation into the following four groups along the
spectrum of communicating vs obstructive HCP. Group 1: patients with a purely absorptive (communicating) HCP. In these patients,
tetraventricular dilatation is usually observed with occasional extraaxial fluid accumulation. An extracranial CSF diversion
(shunt) is the treatment of choice. Group 2: patients with an obstructive component together with a persistent absorptive
component. In these patients, a technically successful endoscopic procedure will not prevent progression of clinical symptoms
of HCP. An extracranial CSF diversion (shunt) should be the treatment of choice even though some of these patients are currently
treated by endoscopy. Group 3: patients with an obstructive component together with a temporary absorptive component. In these
patients, a technically successful ETV should be followed by temporary CSF drainage [via LP, continuous spinal drainage (CLD),
or ventriculostomy] with or without supplemental medical treatment (i.e., Diamox) for several days. Such temporary drainage
may decrease failure rate in this subgroup. Group 4: patients with a purely obstructive HCP. In these patients, an endoscopic
procedure (ETV) is the treatment of choice. According to this spectrum classification, the authors classify different entities
with representative cases and discuss relevancy to treatment options and prognosis.
Results The data suggest that obstructive hydrocephalus in the very young population may be rather a combination of obstructive and
absorptive problem. The outcome of the patient depends mainly not only on the basic pathology causing the hydrocephalus but
also on the treatment that is chosen and its complications. While bleeding and infection represent the major causes for communicating
hydrocephalus, patients with complex pathologies of congenital type and intra- or interventricular obstructions may reflect
obstructive hydrocephalus. Treatment of these patients may be successful by shuntless procedures if the absorptive problem
is not the major component. In transient absorptive hydrocephalus, temporary measures were effective in many cases leading
to successful procedures of ETV and/or posterior-fossa decompression in selected cases.
Conclusions Shuntless procedures are the dream of a pediatric neurosurgeon provided it solves the problem and does not imply unacceptable
risk. However, the benefit has to be evaluated years after the procedure is performed, as only prospective multicenter studies
will truly show which procedure may have the best overall results in the developing child. Until such studies are available,
understanding the basic pathology or the combination of pathologies leading to hydrocephalus in a given child may open the
window of opportunities for other than shunt surgery in many hydrocephalic children with major obstructive component. 相似文献
9.
Masaki Shinoda Tsuyoshi Yamaguchi Yoshimi Tanaka Osamu Sato Sin Kobayashi Yutaka Suzuki 《Child's nervous system》1992,8(4):219-221
Single photon emission computerized tomography (SPECT) is now widely used as one of the tools in evaluating cerebral blood flow (CBF). The authors report the CBF changes in childhood hydrocephalus. Five pediatric cases studied by 123I-IM SPECT in children are presented. The authors counted radioactivities both in early and delayed images in each patient, and calculated the reabsorption ratio (RR). Two negative-RR cases and three positive-RR cases were found. All of the negative-RR patients had a poor prognosis, while all of the positive-RR patients had a favorable outcome. 相似文献
10.
Hiroshi Yamada Shizuo Oi Norihiko Tamaki Satoshi Matsumoto Katsuko Sudo 《Child's nervous system》1992,8(7):394-398
Primary aqueductal stenosis is one of the main causes of congenital hydrocephalus in humans and experimental models. The congenitally hydrocephalic rat strain LEW/Jms is one such model. In this report, we describe further detailed histological features of periaqueductal structure, including the posterior commissure, subcommissural organ (SCO), and ependyma, and discuss the changes in these structures in relation to the cause of hydrocephalus. Coronal sections of the aqueduct in normal rats showed that the usual ependyma was absent in the center of the base facing the dorsal side, which was replaced by tall columnar cells. On the other hand, in hydrocephalic rats the ependyma encircled the aqueductal cavity. In midline sagittal sections, normal and hydrocephalic rats showed the SCO, although the SCO in hydrocephalic rats was shorter than in normal rats. There was also a marked difference between normal and hydrocephalic rats in the dorsoventral dimension of the rostral midbrain. In hydrocephalus, this dimension was large in comparison with normal rats. The superior collicular commissure located caudal to the posterior commissure ran along the ventral side of the midbrain in rats with hydrocephalus, and there was a cell-depleted area just dorsal to the superior collicular commissure. The same findings were observed from the 17th day of gestation until the postnatal period. Although the role of the SCO has been widely discussed from the viewpoint of secretory function, the present study indicated that this organ might be involved in the formation of the shape of the aqueduct. 相似文献