Surgical treatment of tentorial dural arteriovenous fistulae located around the tentorial incisura

Tentorial dural arteriovenous fistulae (DAVF) are relatively uncommon and are the most dangerous type of DAVF. Because of a high incidence of hemorrhage and subsequent neurological deficits, treatment is mandatory. A consecutive series of nine surgically treated patients with symptomatic tentorial DAVF were analyzed in this study. All lesions were located around the tentorial incisura and were treated microsurgically using a subtemporal approach in eight cases and a supracerebellar approach in one case. The dural bases of the lesions were located adjacent to the tentorial edge in six patients and the tentorial apex in three patients. Complete obliteration was achieved in all treated tentorial DAVF. In one patient, the torcular fistula remained untreated without cortical venous reflux. Postoperative asymptomatic temporal lobe hemorrhage was diagnosed in one patient with a tentorial apex DAVF; however, no new neurological symptoms were present after surgical treatment. The subtemporal approach for unilateral tentorial DAVF is a favorable and direct approach for the highly skilled surgeon. Perimesencephalic venous dilatation or varix is an important finding on MRI to help localize tentorial DAVF in the tentorial edge or apex

Neuropathological characteristics of progression after prolonged response to bevacizumab in multifocal hemangioblastoma

Background: Antiangiogenic treatment has been explored in few patients with hemangioblastoma after failure of surgery and radiotherapy. Case Report: We present the first histopathological follow-up study of a bevacizumab-responsive hemangioblastoma that eventually progressed. For a period of 12 months, therapy with bevacizumab achieved a clinical response and radiological stabilization in a patient with progressive multifocal central nervous system (CNS) hemangioblastoma. Subsequently, selected tumor sites showed radiological progression, in particular, the formation of an intramedullary lesion of the initially predominantly leptomeningeal disease. Histology showed diffuse dural invasion by the hemangioblastoma accompanied with a relatively reduced cell density compared to the preserved vessel structures. Conclusion: The pattern of progression upon vascular endothelial growth factor (VEGF)-targeting antiangiogenic treatment in hemangioblastoma may involve increased tumor invasiveness. © 2014 S. Karger GmbH, Freiburg

Development and external validation of a clinical prediction model for functional impairment after intracranial tumor surgery

OBJECTIVE Decision-making for intracranial tumor surgery requires balancing the oncological benefit against the risk for resection-related impairment. Risk estimates are commonly based on subjective experience and generalized num-bers from the literature, but even experienced surgeons overestimate functional outcome after surgery. Today, there is no reliable and objective way to preoperatively predict an individual patient's risk of experiencing any functional impair-ment. METHODS The authors developed a prediction model for functional impairment at 3 to 6 months after microsurgical resection, defined as a decrease in Karnofsky Performance Status of >= 10 points. Two prospective registries in Swit- zerland and Italy were used for development. External validation was performed in 7 cohorts from Sweden, Norway, Germany, Austria, and the Netherlands. Age, sex, prior surgery, tumor histology and maximum diameter, expected major brain vessel or cranial nerve manipulation, resection in eloquent areas and the posterior fossa, and surgical approach were recorded. Discrimination and calibration metrics were evaluated. RESULTS In the development (2437 patients, 48.2% male; mean age +/- SD: 55 +/- 15 years) and external validation (2427 patients, 42.4% male; mean age +/- SD: 58 +/- 13 years) cohorts, functional impairment rates were 21.5% and 28.5%, respectively. In the development cohort, area under the curve (AUC) values of 0.72 (95% CI 0.69-0.74) were observed. In the pooled external validation cohort, the AUC was 0.72 (95% CI 0.69-0.74), confirming generalizability. Calibration plots indicated fair calibration in both cohorts. The tool has been incorporated into a web-based application available at https://neurosurgery.shinyapps.io/impairment/. CONCLUSIONS Functional impairment after intracranial tumor surgery remains extraordinarily difficult to predict, al- though machine learning can help quantify risk. This externally validated prediction tool can serve as the basis for case by-case discussions and risk-to-benefit estimation of surgical treatment in the individual patient.Scientific Assessment and Innovation in Neurosurgical Treatment Strategie

Zu den Anforderungen der Risikoaufklärung von Behandlungsalternativen am Beispiel des intrazerebralen Aneurysmas

All medical subspecialties and, in particular, high-tech field neurosurgery are subject to continuous change in therapeutic concepts due to novel treatment options emerging through research and evolution in the field. Hence, the question arises if the patient's informed consent needs to be adjusted in the face of multiple therapeutic options with different configurations of risk/benefit relationships. In this paper we discuss different therapeutic scenarios with regard to ruptured intracerebral aneurysms (RIA) and unruptured intracerebral aneurysms (UIA), and we advise the medical doctor involved in the process. Indeed, experienced neurosurgeons and endovascular interventionalists are very familiar with the management of these scenarios; likewise, interns, residents, and otherwise affiliated physicians may be faced with these situations. In general, asymptomatic and mentally capacitated patients as well as legal guardians of minor patients and of mentally incapacitated patients with incidental aneurysms and more than one therapeutic option need to be accurately informed about the advantages and disadvantages of the treatment options available to them. In case of emergency or when treating a mentally disabled patient who is incapable of making a sound judgment and has no legal guardian, the attending doctor will have to choose the best possible treatment option. Copyright © 2010. Published by Elsevier GmbH

Intraoperatives Neurophysiologisches Monitoring verbessert das Outcome in der Neurochirurgie

Zusammenfassung: Das Intraoperative Neurophysiologische Monitoring (IONM) identifiziert eloquente Areale oder Nervenbahnen im Operationsgebiet und überwacht ihre Funktion. Inzwischen ist IONM zu einem wichtigen Hilfsmittel in der Neurochirurgie geworden. 1.IONM erhöht die Sicherheit während der Operation. Die Identifikation neuronaler Strukturen kann nicht nur postoperative neurologische Ausfälle vermeiden helfen, sondern auch die Operationszeit verkürzen. 2.IONM kann zur vollständigeren Entfernung von Tumoren beitragen und somit die Überlebensdauer der Patienten verlängern. 3.Komplizierte neurochirurgische Eingriffe, welche mit einem erhöhten Risiko von neurologischen Ausfällen behaftet sind, werden durch IONM erst ermöglicht. Das IONM umfasst eine Vielzahl von verschiedenen Verfahren, die bei fachgerechter Auswahl das Outcome nach neurochirurgischen Eingriffen erwiesenermassen erhöhen. Abstract: Intraoperative Neurophysiological Mo-nitoring (IONM) identifies eloquent areas or nerves fibers during neurosurgical interventions and monitors their function. For several interventions IONM has become mandatory in neurosurgery. IONM increases patient safety during surgery as the risk of neurological deficits is reduced. Safer surgery reduces the time needed for the intervention and thereby reduces risk. IONM contributes to complete resection of tumors, which in turn prolongs patients' survival. Complicated surgical interventions associated with an elevated risk of neurological deficits have only become possible due to IONM. IONM comprises a variety of procedures that are selected for a particular intervention. With appropriate selection of the procedures IONM has been shown to improve neurological and functional outcome after neurosurgical interventions