Recurrent spinal fistula as result of a rare combination of a perimedullary and peridural spinal fistula: case report.

OBJECTIVES: We report on a patient with the combination of a peridural and a perimedullary spinal fistula, which manifested consecutively. The clinical course and diagnostic steps reveal important observations helpful in the management of this pathology. CASE PRESENTATION: A 61-year-old male patient presented with a six-month history of progressive weakness of the lower limbs. Magnetic resonance imaging revealed edema and dilated spinal veins of the lower thoracic spinal cord. Spinal angiography confirmed the diagnosis of spinal dural fistula at level T9 on the left. The patient underwent surgery and the fistula was surgically excised. Two months after initial improvement, the clinical symptoms of lower limb weakness recurred. On re-angiography a spinal perimedullary fistula was found at level T7 that was not apparent on the previous angiogram and on the postoperative control angiogram. The patient underwent surgery again, and the second fistula was also excised. The clinical symptoms subsequently improved. CONCLUSION: The interesting point in this case was the rare combination of a peridural and a perimedullary spinal fistula. They presented consecutively and could not be identified simultaneously on the first angiogram. Only after closure of the first fistula did the second become apparent. We believe that this may be a result of a postoperative pressure change in the venous system of the cord. After closure of the first fistula, the arterio-venous (AV) shunt of the second fistula developed gradually. The possibility of a second fistula should be considered in the presence of persistent edema of the cord on magnetic resonance imaging (MRI) and subsequent clinical deterioration.

Combining MEG and MRI with neuronavigation for treatment of an epileptiform spike focus in the precentral region: a technical case report.

BACKGROUND: Epileptic foci are often located in the vicinity but not necessarily within the boundaries of intra-axial brain tumors. Resection of these tumors is based on two major goals: first, maximizing tumor removal without provoking new neurologic deficits, and second, minimizing epileptic seizure activity. Magnetic source imaging (MSI) depicts the generators of magnetic fields overlaid on individual magnetic resonance (MR) images. Established application areas are lesions located adjacent to or partly within the sensory and motor cortex, or in the depth of the brain, necessitating a surgical approach through functionally highly relevant cortical regions. Magnetoencephalography (MEG) is also applicable for epileptiform spike foci recording during interictal activity. CASE DESCRIPTION: A patient with a recurrent glioma close to the Rolandic cortex scheduled for epilepsy and tumor surgery was investigated with MSI. The MSI data showed an epileptiform spike focus outside the tumor boundaries. The resulting MSI images were integrated into our neuronavigation system. This procedure allowed for the preoperative identification of the sensory and motor cortex, the precise localization of the epileptiform spike focus, and careful planning of the surgical procedure. In this case, we were able to safely resect the recurrent tumor and the epileptiform spike focus under general anesthesia using MSI-based neuronavigational guidance but no conventional intraoperative mapping techniques. CONCLUSION: Magnetic source imaging can be a valuable, noninvasive method for planning and performing tumor resections in high-risk brain regions, especially if an epileptiform spike focus has to be localized and included into the resection strategy.

Neuroendoscopic treatment of idiopathic occlusion of the foramen of Monro in adults--two case reports.

Two adults presented with hydrocephalus due to idiopathic obstruction of the bilateral foramina of Monro, manifesting as clinical signs of chronically elevated intracranial pressure. No inflammation was present. The primary surgical treatment was neuroendoscopic reconstruction of the right foramen of Monro. A 37-year-old man had a spontaneous perforation of the septum pellucidum. The patient required a ventriculoperitoneal shunt, although postoperative ventriculography proved free passage of cerebrospinal fluid from the lateral ventricle into the third ventricle. A 62-year-old man underwent additional septostomy and third ventriculostomy, and the neuroendoscopic intervention relieved the presenting symptoms without additional treatment. The biopsy specimens showed no evidence of malignancy in either case. Neuroendoscopic intervention is an alternative treatment in the management of hydrocephalus due to idiopathic obstruction of the foramen of Monor. The procedure is less invasive than open microsurgical reconstruction and can even avoid ventriculoperitoneal or ventriculoatrial shunting.

Extracellular matrix and the blood-brain barrier in glioblastoma multiforme: spatial segregation of tenascin and agrin.

The quality of the blood-brain barrier (BBB), represented mainly by endothelial tight junctions (TJ), is now believed to be dependent on the brain microenvironment and influenced by the basal lamina of the microvessels. In the highly vascularized glioblastoma multiforme (GBM), a dramatic increase in the permeability of blood vessels is observed but the nature of basal lamina involvement remains to be determined. Agrin, a heparan sulfate proteoglycan, is a component of the basal lamina of BBB microvessels, and growing evidence suggests that it may be important for the maintenance of the BBB. In the present study, we provide first evidence that agrin is absent from basal lamina of tumor vessels if the TJ molecules occludin, claudin-5 and claudin-1 were lacking in the endothelial cells. If agrin was expressed, occludin was always localized at the TJ, claudin-5 was frequently detected, whereas claudin-1 was absent from almost all vessels. Furthermore, despite a high variability of vascular phenotypes, the loss of agrin strongly correlated with the expression of tenascin, an extracellular matrix molecule which has been described previously to be absent in mature non-pathological brain tissue and to accumulate in the basal lamina of tumor vessels. These results support the view that in human GBM, BBB breakdown is reflected by the changes of the molecular compositions of both the endothelial TJ and the basal lamina.

Localization of claudin-3 in tight junctions of the blood-brain barrier is selectively lost during experimental autoimmune encephalomyelitis and human glioblastoma multiforme.

In the central nervous system (CNS) complex endothelial tight junctions (TJs) form a restrictive paracellular diffusion barrier, the blood-brain barrier (BBB). During inflammation, BBB properties are frequently lost, resulting in brain edema. To investigate whether BBB leakiness correlates with molecular changes at BBB TJs, we performed immunofluorescence stainings for TJ molecules in a mouse model of experimental autoimmune encephalomyelitis (EAE) and in human tissue with glioblastoma multiforme (GBM). In TJs of healthy CNS vessels in both mouse and man we detected occludin, ZO-1, claudin-5 and claudin-3. In EAE brain and spinal cord sections we observed the selective loss of claudin-3 immunostaining from TJs of venules surrounded by inflammatory cuffs, whereas the localization of the other TJ proteins remained unchanged. In addition, selective loss of claudin-3 immunostaining was also observed in altered cerebral microvessels of human GBM. Our data demonstrate the selective loss of claudin-3 from BBB TJs under pathological conditions such as EAE or GBM when the integrity of the BBB is compromised, and therefore suggest that claudin-3 is a central component determining the integrity of BBB TJs in vivo.