Arteriovenous malformations of the dura mater]

The authors present two cases of dural arteriovenous malformations treated in Dept. of Neurosurgery, Warsaw Medical School. The main clinical problems of this type of AVM are discussed.     

Infectious prion disease: CJD with dura mater transplantation]

Prion diseases include scrapie, BSE and CWD in animals, and spontaneous, familiar and infectious Creutzfeldt-Jakob disease(CJD) in human. Infectious prion diseases include kuru, variant CJD and iatrogenic CJD. CJD has been transmitted from human to human by contaminated cadaveric dura mater grafts and by cadaveric pituitary hormones. To date, CJD associated with dura mater grafts, reaching 156 cases, has been reported in 17 countries. More 2/3 of cases have been reported in Japan. Nationwide survey and recent information documented 105 dura-related cases during the period between 1979 and 2003. At least 91 cases received same brand of dura mater by a single German company. Age at disease onset in cases with dura-related CJD was younger (54.2 +/- 14.2 years) than sporadic CJD (64 +/- 10 years). Two groups of dura-related CJD are manifest in clinical course and pathological characteristics, such as rapidly progressive group and slowly progressive. Rapidly group was similar to cases with classical CJD in clinical features and shot duration to death from onset. Slowly progressive group developed akinetic mutism longer than 1 year, and characterized by florid plaques in the brain (Kitamoto).     

新型人工硬脑膜和自体膜的对比实验研究

目的通过对新西兰大白兔和本地犬的开颅手术，对比观察应用新型生物型人工硬脑膜及自体骨膜来替代原生硬脑膜的转归。方法全部动物共分为6组，兔9只，分l、6、12个月三组fn=31；犬12只，分12、24个月及更长时间i个组（n=4）。每只动物分别应用新型硬脑膜及自体颅骨膜替代原生硬脑膜，手术后主要观察不同植入物在各组动物体内的转归。结果因两种替代材料替代动物原生硬脑膜6个月或以内实验动物的解剖未达到完全愈合，故呈不典型性，无代表意义。12个月或以后的实验动物解剖显示，两种替代材料外表面与颅骨膜有少许粘连、易分离，与周边缝合的原生硬脑膜已完全愈合，不可分辨，不能分离。从两种替代材料内表面来看，新型人工硬脑膜生长更接近原生硬脑膜．与脑表面无粘连或偶有丝状粘连；而自体骨膜与脑表面有丝状粘连并有少许柱状粘连。组织学镜下显示．植人物与宿主之间无嗜中性粒细胞、淋巴细胞等炎症细胞反应，无囊壁形成。新型人工硬脑膜内表面可见上皮细胞覆盖，上皮下可见纤维组织增生，纤维母细胞增生，植人物被降解，总量明显减少，内部可见毛细血管。结论新型人工硬脑膜的特性使其能产生上皮，不易形成与脑组织的粘连，并逐渐被自体组织蚕食、降解和替代，达到具有实际意义的硬脑膜重建。新型人工硬脑膜在修补硬脑膜缺损的实际应用中比自体膜有更大优越性。     

Heterotopic neuroglial tissue in the cerebral dura mater

The presence of heterotopic neuroglial tissue in the cerebral dura mater has not been documented. This report describes three cases of heterotopic neuroglial tissue in the parasalgittal cerebral dura mater found in a study of 257 adult brains, with an incidence of 1.2%. None were associated with developmental abnormalities of the CNS. The heterotopias were isolated and completely encased within the dura mater with no attachment to the leptomeninges. Their number varied from one to nine. They were composed primarily of astrocytes in a glial network and often stained strongly for glial fibrillary acidic protein and S-100 protein. Oligodendrocyte-like cells were noted but nerve cells, ependyma-lined canals and choroid plexus were absent. Dural neuroglial heterotopias are likely developmental malformations and may represent formes frustes of encephalocele.     

异种硬脑膜替代物移植的研究进展

学术背景：目前用于硬脑膜修复的材料有着许多的不足。因此研制更为理想的硬脑膜替代物仍十分必要。 目的：介绍异种硬脑膜移植的最新研究及应用进展,指导进一步开展异种硬脑膜方面的研究。 检索策略：应用计算机检索PubMed数据库和万方数据知识服务平台1993-01/2008-01的相关文献,检索词为"dura mater,dural substitute ,dural graft,sterilization,Biomedical Materials;硬脑膜,硬脑膜替代物,硬脑膜移植,灭菌,生物材料",限定文章语言分别为英语和中文。检索到文献321篇,其中英文221篇,中文100篇,对文献进行筛选,纳入标准：①选取针对性强,相关度高的文献。②对同一领域的文献选择近期发表或权威杂志的文献;排除重复研究和Meta分析类文章。 文献评价：选用33篇文献,其中1篇为综述、其余均为临床与实验研究。 资料综合：从与异种移植密切相关的感染、术后修复及免疫原性3个重要问题对替代物灭菌及保存的方法、术后排斥反应及修复机制的最新研究加以综述。目前用于异种硬脑膜替代物灭菌的方法有：戊二醛浸泡法、过氧乙酸-乙醇浸泡法、环氧乙烷熏蒸法及辐照法;用于保存硬脑膜替代物的方法主要有冷冻干燥法和深低温冷冻法。硬脑膜主要表达MHC-I类抗原,抗原主要位于含量甚少的内皮细胞和血管内皮上,是一种弱抗原物质,且异种硬脑膜移植属于结构移植,术后很少出现排斥反应。成纤维细胞是硬脑膜修复的主要细胞,它的逸出、增殖是硬脑膜缺损修复的重要机制。 结论：异种硬脑膜替代物因其组织相容性好、术后感染发生率低、来源丰富、价格低廉等优点,具有广泛的临床应用前景。     

冻干辐照猪硬脑膜的抗原性

背景：抗原性是异种组织移植最主要的问题,是移植成功与否的关键。目的：观察经冻干辐照处理后的猪硬脑膜抗原性变化。方法：取新鲜猪硬脑膜,经冻干、辐照处理后分别制备成冻干猪硬脑膜、辐照猪硬脑膜和冻干辐照猪硬脑膜。分别移植于大白兔硬脑膜上,于术后3,8周行各组实验动物淋巴细胞毒实验。结果与结论：移植冻干组和辐照组淋巴细胞死亡率比较差异无显著性意义(P > 0.05),但均高于冻干辐照组(P < 0.05)。结果提示经冻干辐照处理后的猪硬脑膜抗原性低。     

A case of peripheral-type primitive neuroectodermal tumor arising in the dura mater at the frontal base]

A 7-year-old boy was admitted to our hospital because of headache and frequent vomiting. The patient was noted to have papilloedema and mild palsy of the right abducent nerve. Magnetic resonance image (MRI) revealed a large tumor in the frontal base with tumoral hemorrhage. Angiography showed the tumor was fed by anterior meningeal arteries. At surgery, the tumor was arising in the dura mater at the frontal base, and was removed totally. Histological examination showed the tumor to be composed of small cells with uniform round nuclei and minimal cytoplasm. Immunohistochemical studies were positive for MIC-2, NSE, C-KIT, vimentin, Class III-beta tublin and glycogen, but negative for NFP, synaptophysin, chromogranin A and GFAP. MIB-1 labeling index was 40-50%. The tumor was histologically confirmed to be peripheral-type primitive neuroectodermal tumor(pPNET). Following surgery, he underwent whole brain, whole spine and local radiation therapy(30 Gy in total respectively) and received two 5-day cycles of chemotherapy, consisting of intravenous administration of cisplatin 20 mg/m2/day, etoposide 60 mg/m2/day and IFOS 900 mg/m2/day. After these therapies, follow-up radiological examination showed there was no recurrence of the tumor for 24 months. Intracranial pPNET is rare. Ewing sarcoma and pPNET(ES/pPNET) is the designation given to a family of small round cell tumor arising in bone or soft tissues. Intracranial PNETs are devided into central nervous system PNET(cPNET) and pPNET. It is necessary that intracranial PNETs are divided into two types of PNETs because of different prognosis between these tumors. MIC-2 is a specific marker for pPNET/ES family and is useful in the differential diagnosis of these two types of tumors.     

Incidence and distribution of neomembranes of dura mater

Membranous or membranous-haemorrhagic lesions of the dura mater were found in 46 out of 1,044 consecutive necropsies after excluding those cases where their presence could be interpreted in terms of blood dyscrasia, local neoplastic processes, previous surgery, or marked craniocerebral trauma. The extent of old and recent manifestations of haemorrhage in the membranes increased in a statistically significant relation with their size and thickness. Lesions of different types, or degrees, respectively, were often combined in the same case; a remarkably high incidence of membranous lesions in the falx cerebri was noted. The observations indicate the presence of a progressive, repetitive process in neomembrane formation.     

Sympathetic innervation of the supratentorial dura mater of the rat

The origin, density, and distribution of sympathetic nerve fibers in the supratentorial dura mater of the rat were examined in detail in the current study by using wheat germ agglutinin horseradish peroxidase (WGA-HRP) retrograde tracing procedures, glyoxylic acid-induced fluorescence, and dopamine beta-hydroxylase (DBH) immunocytochemical staining of dural whole mount preparations. Application of WGA-HRP to the superior sagittal sinus and adjacent areas of the supratentorial dura mater labeled numerous neurons in each of the left and right superior cervical ganglia. Glyoxylic acid and DBH immunocytochemical staining of fixed dural whole mount preparations revealed prominent plexuses of sympathetic nerves about the middle meningeal artery and its branches, about the superior sagittal and transverse sinuses, and "free" within the dura mater, i.e., apparently unassociated with any vasculature. Significantly, in all of these areas, the density of sympathetic innervation revealed in this study was considerably greater than that previously demonstrated by other workers. An impressive population of mast cells also was observed within the dura mater of the glyoxylic acid-treated preparations. The majority of these cells were perivascular; however, a significant number were also present within the dura unrelated to the vasculature, and occasional cells were seen in close apposition to fluorescent sympathetic nerve fibers. Taken together, the identification of a robust sympathetic plexus and prominent mast cell population associated with a dura mater that also receives significant sensory projections from the trigeminal system raises interest regarding the functional interactions of these elements. These observations warrant further consideration regarding their role in the pathogenesis of vascular headache and head pain.     

Dynamics of the cerebrospinal fluid and the spinal dura mater

During myelography we observed the contrast material in the spinal subarachnoid space while we changed: (1) the intracranial blood volume by CO₂ inhalation, hyperventilation, and jugular vein compression; (2) the intra-abdominal and intrathoracic pressure by forced expiration with glottis closed; and (3) the CSF volume by withdrawals and reinjections of fluid. The spinal dural sac enlarges with increases in volume of both intracranial blood and CSF. It partially collapses with reductions in volume of both intracranial blood and CSF. With increases in intra-abdominal and intrathoracic pressure, the thoracolumbar sac partially collapses, while the cervical sac enlarges. From these observations we conclude that the spinal dural sac is a dynamic structure, readily changing its capacity in response to prevailing pressure gradients across its walls. It acts as a reservoir for CSF, which moves to and fro through the foramen magnum in response to changes in cerebral blood flow. By its bladder-like ability to alter its capacity, the spinal dural sac provides the `elasticity' of the covering of the central nervous system.     

Peptidergic and serotoninergic innervation of the rat dura mater.

The peptidergic and serotoninergic innervation of the rat dura mater was investigated by reacting dural wholemounts immunohistochemically with antibodies to calcitonin gene-related peptide (CGRP), substance P (SP), neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), and serotonin (5-HT). CGRP and SP innervations of the dura were robust and the patterns of distribution of these neuropeptides were essentially the same. The majority of the fibers were perivascular and distributed to branches of the anterior and middle meningeal arteries and to the superior sagittal and transverse sinuses. Other CGRP/SP fibers appeared to end "free" within the dural connective tissue. NPY-immunoreactive fibers were extremely numerous and also distributed heavily to the branches of the meningeal arteries, the venous sinuses, and to the dural connective tissue. The pattern of NPY innervation resembled in many ways that of CGRP/SP; however, NPY innervation of the sinuses was greater and NPY perivascular fibers supplying the meningeal arteries formed more intimate contacts with the walls of the vessels. The pattern of VIP innervation was, in general, similar to that observed for the three previous neuropeptides; however, the overall density was considerably less. Small to moderate numbers of serotoninergic nerve fibers were observed in some, but not all, of the duras processed for 5-HT. The latter fibers were almost exclusively perivascular in distribution. Dural mast cells were prominently stained in the 5-HT preparations because of their serotonin content. Mast cells were also labeled in a nonspecific fashion in some of the tissues reacted immunohistochemically for neuropeptides; some of them were located in close apposition to passing nerve fibers. This study represents, to our knowledge, the first comprehensive work on the peptidergic and serotoninergic innervation of the mammalian dura mater. The results should increase our understanding of the roles that these fibers play in normal dural physiology and of their potential interactions in the pathogenesis of vascular headache.