Optical requirements on magnification systems for intracranial video microsurgery.

Introduction: The basic idea of video-microsurgery is the improvement of ergonomic conditions in microsurgical procedures by replacing the bulky operating microscope with a compact videosystem.

Objective: To specify optical requirements on a videosystem for microsurgical intracranial procedures in neurosurgery.

Methods: During 27 microsurgical intracranial procedures (12 cerebellopontine angle and 15 supratentorial) zoom factor, focus distance and illumination parameters of the operating microscope were continuously recorded.

Specific intensity imaging for glioblastoma and neural cell cultures with 5-aminolevulinic acid-derived protoporphyrin IX.

The fluorescence of protophorphyrin IX (PpIX) synthesized after incubation with 5-aminolevulinic acid (5-Ala) is used for the intraoperative visualisation of glioma cells in vivo. Such fluorescence may also be useful for the photodynamic therapy (PTD) of gliomas. A significant difference of fluorescence intensity in tumor cells compared to neurons is required for this application.

P-glycoprotein and multidrug resistance-associated protein mediate specific patterns of multidrug resistance in malignant glioma cell lines, but not in primary glioma cells.

Understanding and overcoming multidrug resistance (MDR) may be a promising strategy to develop more effective pharmacotherapies for malignant gliomas. In the present study, human malignant glioma cell lines (n=12) exhibited heterogeneous mRNA and protein expression and functional activity of the mdr gene-encoded P-glycoprotein (PGP) and MDR-associated protein (MRP). Correlation between mRNA expression, protein levels and functional activity was strong.

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).

Influence of geometric and hemodynamic parameters on aneurysm visualization during three-dimensional rotational angiography: an in vitro study.

Background And Purpose: Aneurysm depiction with three-dimensional (3D) rotational angiography is influenced by investigator-defined parameters such as image acquisition and contrast agent injection and by the hemodynamic pattern in the parent artery and aneurysm. To assess the impact of the geometric configuration of parent artery and aneurysm on the 3D visualization of saccular aneurysms, we studied silicone aneurysm models under pulsatile-flow conditions.

Methods: Rotational angiography was performed in three bifurcation and three lateral aneurysm models with ostia of different widths.

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.

Subdural hygroma as a complication of endoscopic neurosurgery--two case reports.

Two cases of subdural hygroma occurred in a series of 77 neuroendoscopic procedures. An 8-year-old boy underwent neuroendoscopic cysto-cisternostomy of a left temporal arachnoid cyst. Routine postoperative magnetic resonance imaging 7 days later showed a large left-sided subdural hygroma without clinical symptoms.

Neoadjuvant gemcitabine/treosulfan chemotherapy for newly diagnosed glioblastoma: a phase II study.

The median survival for patients with glioblastoma is 12 months. The authors evaluated whether preirradiation gemcitabine/treosulfan (GeT) chemotherapy followed by standard radiotherapy improved outcome in patients with glioblastoma. Seventeen patients with newly diagnosed glioblastoma were enrolled in a prospective, unicenter trial of preirradiation GeT chemotherapy.

Simultaneous virtual representation of both vascular and neural tissue within the subarachnoid space of the basal cistern--technical note.

Background: The representation of different anatomical structures requires varying imaging modalities and protocols. By mental composition of single-slice images, a three-dimensional (3D) impression can be achieved. However, this presupposes an outstanding imagination and is subject to inaccuracies.

Novel multipurpose bipolar instrument for endoscopic neurosurgery.

Objective: Hemorrhage control in endoscopic neurosurgery is critical because of the lack of suitable instruments for coagulation. One reason for this problem is that miniaturization of the instruments is still a technical problem. In this article, we present a solution: the use of bipolar microforceps with a small diameter of 1.

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.

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.

Radiosurgery for brain metastases: the Tuebingen experience.

Purpose: To retrospectively investigate the effectiveness of linear accelerator based radiosurgery (RS) in the treatment of brain metastases (BM).

Material And Methods: Of 55 patients with a total of 72 BM, 41 patients had a single brain metastasis and 14 patients had two or three metastases. Median tumour dose of 15Gy (range 8-20Gy) was prescribed to a median isodose surface of 90% (range 70-100%) encompassing the target volume.