The purpose of this study is to assess the diagnostic performance of diffusion kurtosis imaging (DKI) for in vivo molecular profiling of human glioma. Normalized mean kurtosis (MK) and mean diffusivity (MD) metrics from DKI were assessed in 50 patients with histopathologically confirmed glioma. The results were compared in regard to the WHO-based histological findings and molecular characteristics leading to integrated diagnosis (Haarlem Consensus): isocitrate-dehydrogenase (IDH1/2) mutation status, alpha-thalassemia/mental retardation syndrome X-linked (ATRX) expression, chromosome 1p/19q loss of heterozygosity (LOH), and O6-methylguanine DNA methyltransferase (MGMT) promoter methylation status.
View Article and Find Full Text PDFSynchronous (early) and metachronous (late) brain metastasis (BM) events of sporadic clear cell renal cell carcinoma (ccRCC) (n = 148) were retrospectively analyzed using comparative genomic hybridization (CGH). Using oncogenetic tree models and cluster analyses, chromosomal imbalances related to recurrence-free survival until BM (RFS-BM) were analyzed. Losses at 9p and 9q appeared to be hallmarks of metachronous BM events, whereas an absence of detectable chromosomal changes at 3p was often associated with synchronous BM events.
View Article and Find Full Text PDFThe significance of electrophysiological phenomena is well validated in brain ischemia research. A close link with interstitial amino acid levels has not been proved convincingly but is generally assumed. This has given widespread rise to the clinical method of amino acid, especially glutamate, microdialysis.
View Article and Find Full Text PDFA new remote-controlled interface-type chamber was designed in order to conduct experiments in brain slices involving gas, fluid, and temperature changes with as little tissue manipulation as possible. The chamber allows for extremely quick changes between different fluid and/or gaseous phases and for active cooling as well as heating by using a set of electromechanical valves and Peltier elements. The design drawings are complemented by exemplary tests of temperature and gas changes, and electrophysiological recordings of slices manipulated with gas and fluid alterations were used to test the efficacy and accuracy of the design.
View Article and Find Full Text PDFSymptomatic degenerative central lumbar spinal stenosis (LSS) is a frequent indication for decompressive spinal surgery, to reduce spinal claudication. No data are as yet available on the effect of surgery on the level of activity measured with objective long-term monitoring. The aim of this prospective, controlled study was to objectively quantify the level of activity in central LSS patients before and after surgery, using a continuous measurement device.
View Article and Find Full Text PDFDietary restriction has been shown to be associated with marked changes in brain function. Periodic fasting was suggested to be beneficial in reducing both the incidence and severity of some neurological disorders. The aim of this investigation was to study the effect of periodic fasting on the neuronal network excitability in the neocortex and hippocampus and its possible influence on the brain under pathological conditions.
View Article and Find Full Text PDFObjectives: Coexisting intracerebral aneurysms and meningiomas occur relatively rarely, without a clear relationship, although an aneurysm can be located within a meningioma. The aim of this retrospective study was to identify possible explanations for the coexistence of these conditions and to present a rationale for treatment strategies.
Patients And Methods: Ninety-five patients with coexistent meningioma and aneurysm were found in the National Library of Medicine, and 11 more patients were retrieved from our own database.
Cerebrovascular diseases and especially ischemic stroke are a leading cause of death. They occur mostly due to an insufficient oxygen (O2) supply to the central neural tissue as a result of thromboembolic events and/or obstructive vessel disease. The primary damage of the brain tissue cannot be restored.
View Article and Find Full Text PDFBackground: The therapeutic use of pure oxygen, even under hyperbaric conditions, has been well established for about 50 years, whereas the discovery of oxygen occurred 250 years earlier. Many neurosurgical patients suffer from brain tissue damage, due to reduced blood flow, obstructive vessel disease, or as a result of traumatic brain injury.
Methods And Results: The application of pure oxygen in these patients is the only method of increasing the O(2) concentration in tissue with impaired blood supply and can minimize secondary impairment of brain tissue.
Object: Aneurysmal subarachnoid hemorrhage (SAH) carries a severe prognosis, which is often related to the development of cerebral vasospasm. Even though several clinical and radiological predictors of vasospasm and functional outcome have been established, the prognostic value of histopathological findings remains unclear.
Methods: Histopathological findings in resected distal aneurysm walls were examined, as were the clinical and radiological factors in a series of 91 patients who had been neurosurgically treated for aneurysmal SAH.
While the vasomotor effects of pCO(2) modulation are well documented, the influence of the carbon dioxide-bicarbonate system on the ischemia tolerance of brain tissue itself is controversial. Guinea-pig hippocampal tissue was subjected to ischemia simulation in an interface environment and examined electrophysiologically. Characteristics of anoxic depolarization as well as the postischemic recovery of evoked potentials were registered.
View Article and Find Full Text PDFObjective: Synovial cysts are an important differential diagnosis in lumbar radiculopathy.
Patients And Methods: From 2000 to 2005, we treated 32 patients (22 female, 10 male) suffering from lumbar radiculopathy due to spinal synovial cysts. The mean age was 64 years (range 42-84).
We report the rare case of a 74-year-old man who was admitted to our hospital with rapid progression of tetraparesis, which was most apparent in the lower right limb, sensory disturbances from C3 to S1 on the left side and recent onset of constipation and urinary retention. There was no known history of cancer. As MRI of the neck disclosed a cervical intramedullary mass lesion at C 4/5 level suspicious for a primary glial tumour, the patient underwent surgery.
View Article and Find Full Text PDFObjective: Today most cervical intervertebral implants (cages) have at least one cranio-caudal hole which can be filled to facilitate bony fusion. Whether this should be done or not remains a matter of debate. The assessment of bony fusion remains difficult, especially in titanium implants.
View Article and Find Full Text PDFBackground: Amyloid deposits within the brain can be found in a heterogeneous group of diseases. Some of them involve only the central nervous system (AD); others are of systemic origin. Isolated deposits either in the brain, cranial nerves or within the spinal neural structures are extremely rare.
View Article and Find Full Text PDFAnasthesiol Intensivmed Notfallmed Schmerzther
January 2007
Neuroaxial anesthesia has become an integral part of perioperative pain therapy and provides several advantages over systemic opioids. Despite these benefits, rare but serious complications occur with epidural analgesia including epidural haematoma, spinal-epidural infections and local anesthetic cardiac toxicity. Epidural haematoma and epidural abscess after catheter placement may cause irreversible neurological complications and an immediate diagnostic and therapeutic approach is crucial to assure complete recovery.
View Article and Find Full Text PDFZentralbl Neurochir
November 2006
Objective: After anterior cervical discectomy the implantation of a spacer is common practice. The majority of these spacers are trapezoid titanium cages. During the development of a height-adjustable cervical implant we needed to establish the testing limits for this device.
View Article and Find Full Text PDFThe implantation of a spacer is common practice after ventral discectomy in the cervical spine. Besides bone or bone cement (Palacos, Sulfix, and Allofix), the surgeon has the choice of a variety of factory-made implants (cages). We report on our experience with the Intromed ZWE [Zwischenwirbel-Ersatzsystem (Intervertebral Replacement System)] implant.
View Article and Find Full Text PDFZentralbl Neurochir
February 2007
Introduction: Nonautologous interbody fusion materials are utilised in increasing numbers after anterior cervical disc surgery to overcome the problem of donor site morbidity of autologous bone grafts. This study investigates the performance of two nonautologous materials, the bone cement Polymethylmethacrylate (PMMA) and titanium cages. This prospective randomised trial, with assessment of the results by an independent observer, evaluates whether a Polymethylmethacrylate (PMMA) spacer or a titanium cage provides a better fusion rate around the implant and a better clinical outcome.
View Article and Find Full Text PDFBackground: Virtual endoscopy (VE) is a new and promising imaging technology. Applied to neuroendoscopy it allows preoperative simulation of a procedure and evaluation of the individual intraventricular anatomy in selected cases. Along with neuronavigation and real time intraoperative imaging, VE is expected to improve the safety and efficacy of neuroendoscopic procedures.
View Article and Find Full Text PDFObjective: In contrast to cranial neuro-navigation, which has been accepted as a routine intraoperative tool, there is still much debate about spinal navigation as an aid for the insertion of pedicle screws. Opinions range from "not useful at all" to "malpractice if not using it". The aim of our investigation was to obtain data about the availability of spinal navigation and compile a common opinion among German neurosurgeons about its usefulness.
View Article and Find Full Text PDFObjective: Traumatic brain injury is frequently accompanied by a systemic inflammatory response. Systemic inflammation was associated with cerebral hyperperfusion uncoupled to global oxygen metabolism in ovine head trauma. The present study investigated the cerebral effects of cerebral perfusion pressure (CPP) management performed by either fluid resuscitation or vasopressor treatment of low CPP induced by systemic inflammation.
View Article and Find Full Text PDFIschemia models are indispensable for the evaluation of measures to be clinically applied to brain trauma or stroke patients. Slice models provide good control over experimental parameters and allow for comparative examinations of human and animal brain tissue. Experimental tissue, however, may be altered by anaesthesia, preparatory technique, and, in the case of human tissue, by underlying diseases.
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