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Dive into the research topics where Christian F. Freyschlag is active.

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Featured researches published by Christian F. Freyschlag.


Central European Neurosurgery | 2015

A Sandwich Technique for Prevention of Cerebrospinal Fluid Rhinorrhea and Reconstruction of the Sellar Floor after Microsurgical Transsphenoidal Pituitary Surgery.

Christian F. Freyschlag; Stephanie Goerke; Jochen Obernauer; Johannes Kerschbaumer; Claudius Thomé; Marcel Seiz

BACKGROUND Cerebrospinal fluid (CSF) leaks are a well-known complication of transsphenoidal surgery. Several autologous and artificial grafts have been used to close the sellar floor in an attempt to prevent postoperative CSF rhinorrhea. OBJECTIVE To evaluate and describe a sandwich technique to close the sellar floor using autologous bone, absorbable gelatin sponge, and coated collagen fleece. METHODS We reviewed 50 consecutive patients between April 2010 and August 2011 who underwent transsphenoidal surgery ending with reconstruction of the sellar floor with a particular sandwich technique. Patients with an intraoperative CSF leak received an additional lumbar drain. RESULTS There were no cases of CSF rhinorrhea at postoperative follow-up after 6 weeks and no revision surgery. CONCLUSION The proposed sandwich technique for closure of the sellar floor to the sphenoid sinus is a suitable alternative to autologous grafts and seems to be effective in preventing CSF rhinorrhea.


Neurosurgical Review | 2017

Brain tumors in eloquent areas: A European multicenter survey of intraoperative mapping techniques, intraoperative seizures occurrence, and antiepileptic drug prophylaxis

Giannantonio Spena; Philippe Schucht; Kathleen Seidel; Geert-Jan Rutten; Christian F. Freyschlag; Federico D’Agata; Emanule Costi; Francesca Zappa; Marco Fontanella; Denys Fontaine; Fabien Almairac; Michele Alessandro Cavallo; Pasquale De Bonis; Gerardo Conesa; Nicholas Foroglou; Santiago Gil-Robles; Emanuel Mandonnet; Juan Martino; Thomas Picht; Catarina Viegas; Michel Wager; Johan Pallud

Intraoperative mapping and monitoring techniques for eloquent area tumors are routinely used world wide. Very few data are available regarding mapping and monitoring methods and preferences, intraoperative seizures occurrence and perioperative antiepileptic drug management. A questionnaire was sent to 20 European centers with experience in intraoperative mapping or neurophysiological monitoring for the treatment of eloquent area tumors. Fifteen centers returned the completed questionnaires. Data was available on 2098 patients. 863 patients (41.1%) were operated on through awake surgery and intraoperative mapping, while 1235 patients (58.8%) received asleep surgery and intraoperative electrophysiological monitoring or mapping. There was great heterogeneity between centers with some totally AW oriented (up to 100%) and other almost totally ASL oriented (up to 92%) (31% SD). For awake surgery, 79.9% centers preferred an asleep-awake-asleep anesthesia protocol. Only 53.3% of the centers used ECoG or transcutaneous EEG. The incidence of intraoperative seizures varied significantly between centers, ranging from 2.5% to 54% (p < 0.001). It there appears to be a statistically significant link between the mastery of mapping technique and the risk of intraoperative seizures. Moreover, history of preoperative seizures can significantly increase the risk of intraoperative seizures (p < 0.001). Intraoperative seizures occurrence was similar in patients with or without perioperative drugs (12% vs. 12%, p = 0.2). This is the first European survey to assess intraoperative functional mapping and monitoring protocols and the management of peri- and intraoperative seizures. This data can help identify specific aspects that need to be investigated in prospective and controlled studies.


Neurosurgical Review | 2018

Severe head injury in very old patients: to treat or not to treat? Results of an online questionnaire for neurosurgeons

Claudia Unterhofer; Sebastian Hartmann; Christian F. Freyschlag; Claudius Thomé; Martin Ortler

Due to the aging population, neurosurgeons are confronted with an increasing number of very old patients suffering from traumatic brain injury. Many of these patients present with an acute subdural hematoma. There is a lack of data on neurosurgical decision-making in elderly people. We investigated the importance of imaging criteria, patients’ wishes, their surrogates’ wishes, and patient demographics on treatment decisions chosen by neurosurgeons. An online questionnaire was sent to all German neurosurgical units via the German Society of Neurosurgery (DGNC). The survey was based on the reported case of an unconscious 81-year-old patient with an acute subdural hematoma and consisted of 13 questions. Of these questions, nine addressed indication and treatment plan and four evaluated the neurosurgeon’s interest in gathering additional information on the patient’s social environment and supposed patient’s wishes or advance directive. Eighty-five percent of the interviewed neurosurgeons would perform an emergency operation in the presented case. Midline shift (84%), hematoma thickness (81%), and time between traumatic injury and treatment (81%) were considered to be the most important factors for surgical treatment. Gathering information on the social environment of the patient (66%) and discussion with family members (57%) were felt to be either unimportant. Neurosurgeons in Central Europe tend to treat acute subdural hematoma in very old patients based on imaging findings and according to mechanistic views. Social circumstances and patient wishes are considered to be less important. Education of the medical profession and the general public should aim to bring these factors into focus in the decision-making process.


Brain Informatics | 2017

Preoperative prediction of language function by diffusion tensor imaging

Christian F. Freyschlag; Johannes Kerschbaumer; Daniel Pinggera; Thomas Bodner; Astrid E. Grams; Claudius Thomé

For surgery of eloquent tumors in language areas, the accepted gold standard is functional mapping through direct cortical stimulation (DCS) in awake patients. Ever since, neuroscientists are searching for reliable noninvasive detection of function in the human brain, with variable success. The potential of diffusion tensor imaging (DTI) in combination with computational cortical parcellation to predict functional areas in language eloquent tumors has not been assessed so far. We present a proof-of-concept report involving awake surgery for a temporodorsal tumor. Postoperatively, the imaging was extensively studied and a predictive value of multimodal MR imaging for the possible extent of resection was analyzed. After resection using DCS, the extent of resection and functional outcome were correlated with the processed imaging. Preoperative imaging of our patient was taken to compute the lesion volume as a seed for tractography (DTI) and combined with a tractography of the entire hemisphere. For better spatial resolution, an elastic image fusion was performed to correct the distortion of DTI data. After subtotal resection and imaging analysis, the status of the superior part of the lesion could be identified and predicted as functional cortex. There was a strong correlation between the tumor remnant during surgery and the imaging parameters of DTI connectivity of the eloquent tissue. A combination of complex DTI processing may be able to predict function in a patient suffering eloquent brain tumors and thus allow estimation of extent of resection.


World Neurosurgery | 2016

Disseminated Intravascular Coagulation in Secondary Glioblastoma due to Excessive Intraoperative Bleeding: Case Report and Review of the Literature.

Daniel Pinggera; Johannes Kerschbaumer; Nicole Innerhofer; Adelheid Woehrer; Christian F. Freyschlag; Claudius Thomé

BACKGROUND Disseminated intravascular coagulation (DIC) describes a pathologic activation of coagulation mechanisms, leading to thrombi in various organs with contribution to multiple organ failure. In clinical practice, diagnosis of DIC can often be made by laboratory values, including prolonged coagulation times, thrombocytopenia, or high levels of fibrin degradation products. DIC is frequently observed after neurotrauma, but rarely occurs in patients with primary brain tumors. There are only few case reports of DIC in patients with primary brain tumors, all sharing the highly elevated mortality. We report the case of a young patient presenting with secondary glioblastoma, who developed multiorgan failure induced by DIC after extensive intraoperative bleeding. CASE DESCRIPTION A 30-year-old patient was admitted in poor general condition with insomnia, severe headache, and vomiting. She had undergone surgery for secondary glioblastoma twice. Magnetic resonance imaging revealed a left temporoparietal mass lesion with indication for resection. Surgery then was complicated by diffuse intraoperative bleeding due to a high content of microvascular proliferation as shown in the histopathologic workup. Subsequently, an uncontrollable multiorgan failure developed, causing the patients death 4 days after surgery. CONCLUSIONS Although a rare complication, excessive intraoperative bleeding, especially in surgery for brain tumors located next to the ventricular system, DIC should be kept in mind as a possible diagnosis.


World Neurosurgery | 2018

Accuracy Validation of Neuronavigation Comparing Headholder-Based System with Head-Mounted Array—A Cadaveric Study

Daniel Pinggera; Johannes Kerschbaumer; Marlies Bauer; Marina Riedmann; Markus Conrad; Erich Brenner; Claudius Thomé; Christian F. Freyschlag

BACKGROUND Neuronavigation is widely used for intracranial neurosurgical procedures and is commonly based on the standard reference array being fixed to the headholder. Some cases require the reference array to be attached directly to the head. The aim of this cadaveric study was to compare operational accuracy of a head-mounted reference array with the standard headholder-based system. METHODS Navigation accuracy was evaluated with 10 cadaveric specimens. Each specimen was prepared with 8 titanium microscrews that served as reference points on the external skull, and computed tomography was performed. Registration of all specimens was done using surface matching with infrared laser on three-dimensional reconstructed high-resolution computed tomography. In all 10 specimens, the head-mounted reference array and headholder-based system were compared by 10 repetitive measurements. The deviation was evaluated for each screw and compared using nonparametric Mann-Whitney U test between groups and screws. A Bland-Altman plot was generated for comparison. RESULTS A total of 1600 measurements were conducted. Mean deviation was 1.97 mm (95% confidence interval, 1.90-2.03 mm) with the head-mounted reference array and 2.10 mm (95% confidence interval, 2.04-2.18 mm) with the headholder based system. There was no significant difference between methods in 9 of 10 specimens. In 1 specimen, the head-mounted array was superior. The deviation in either method showed a significant correlation, indicating high pertinence for registration (P < 0.001). CONCLUSIONS Navigation with the head-mounted reference array demonstrated comparable accuracy to the headholder-based system and can be used without reduced accuracy. Careful registration is mandatory.


Cancers | 2018

Audencel Immunotherapy Based on Dendritic Cells Has No Effect on Overall and Progression-Free Survival in Newly Diagnosed Glioblastoma: A Phase II Randomized Trial

Johanna Buchroithner; Friedrich Erhart; Josef Pichler; Georg Widhalm; Matthias Preusser; Günther Stockhammer; Martha Nowosielski; Sarah Iglseder; Christian F. Freyschlag; Stefan Oberndorfer; Karin Bordihn; Gord von Campe; Markus Hoffermann; Reinhard Ruckser; Karl Rössler; Sabine Spiegl-Kreinecker; Michael B. Fischer; Thomas Czech; Carmen Visus; Günther Krumpl; Thomas Felzmann; Christine Marosi

Dendritic cells (DCs) are antigen-presenting cells that are capable of priming anti-tumor immune responses, thus serving as attractive tools to generate tumor vaccines. In this multicentric randomized open-label phase II study, we investigated the efficacy of vaccination with tumor lysate-charged autologous DCs (Audencel) in newly diagnosed glioblastoma multiforme (GBM). Patients aged 18 to 70 years with histologically proven primary GBM and resection of at least 70% were randomized 1:1 to standard of care (SOC) or SOC plus vaccination (weekly intranodal application in weeks seven to 10, followed by monthly intervals). The primary endpoint was progression-free survival at 12 months. Secondary endpoints were overall survival, safety, and toxicity. Seventy-six adult patients were analyzed in this study. Vaccinations were given for seven (3–20) months on average. No severe toxicity was attributable to vaccination. Seven patients showed flu-like symptoms, and six patients developed local skin reactions. Progression-free survival at 12 months did not differ significantly between the control and vaccine groups (28.4% versus 24.5%, p = 0.9975). Median overall survival was similar with 18.3 months (vaccine: 564 days, 95% CI: 436–671 versus control: 568 days, 95% CI: 349–680; p = 0.89, harzard ratio (HR) 0.99). Hence, in this trial, the clinical outcomes of patients with primary GBM could not be improved by the addition of Audencel to SOC.


CNS oncology | 2018

Efficacy of D,L-methadone in the treatment of glioblastoma in vitro

Konstantin Brawanski; Gero Brockhoff; Peter Hau; Arabel Vollmann-Zwerenz; Christian F. Freyschlag; Annette Lohmeier; Markus J. Riemenschneider; Claudius Thomé; Alexander Brawanski; Martin Proescholdt

Aim: Recently, D,L-methadone has been put forward as adjuvant treatment in glioblastoma (GBM). Methods: We analyzed the μ-opioid receptor expression in a set of GBM cell lines and investigated the efficacy of D,L-methadone alone and in combination with temozolomide (TMZ). Results & conclusion: Expression of the μ-opioid receptor was similar in the tested cell lines. High concentrations of D,L-methadone induced apoptosis in all cell lines and showed treatment interaction with TMZ. However, in lower dosages, reflecting clinically attainable concentrations, D,L-methadone alone showed no efficacy, and induced even higher proliferation in one specific cell line. Also, no interaction with TMZ was observed. These results suggest caution to the premature use of D,L-methadone in the treatment of GBM patients.


World Neurosurgery | 2017

The Volume of the Third Ventricle as a Prognostic Marker for Shunt Dependency After Aneurysmal Subarachnoid Hemorrhage

Daniel Pinggera; Johannes Kerschbaumer; Ondra Petr; Martin Ortler; Claudius Thomé; Christian F. Freyschlag

BACKGROUND Hydrocephalus is a common sequelae of aneurysmal subarachnoid hemorrhage (aSAH). However, in daily routine it is difficult to predict a patients need for ventricular shunt placement in the course of the disease. OBJECTIVE The purpose of this study was to identify radiologic predictors for development of a shunt-dependent hydrocephalus after aSAH. METHODS A cohort of 217 patients with aSAH with adequate pretreatment computed tomography (CT) imaging was retrospectively reviewed. All variables, including demographic data, treatment, and initial CT imaging were gathered and grading was performed using Hunt and Hess, Graeb, LeRoux, and modified Fisher scores. Analysis of the radiographic parameters consisted of straight measurement and three-dimensional volumetry using manual segmentation. Univariate and multivariate statistical analyses were performed to identify predictive parameters. RESULTS Of 217 patients, 36 (17.5%) required a ventricular shunt (VS). A receiver operating characteristic analysis between the volume of the third ventricle and shunt-dependent hydrocephalus showed a significant cutoff at a volume of 2.3 cm3 with a 4.3-fold higher risk for shunt dependency (P < 0.001). However, the treatment modality and classification according to the mentioned scores were not associated with the need for VS after aSAH. In univariate and multivariate analysis, the volume of the third ventricle on admission remained a significant prognostic marker for the need of a VS. CONCLUSIONS Our data suggest that the volume of the third ventricle in the initial CT is a strong predictor for shunt dependency after aSAH.


Neuro-oncology | 2017

Comment on: Neurocognitive function varies by IDH1 genetic mutation status in patients with malignant glioma prior to surgical resection

Christian F. Freyschlag; Johannes Kerschbaumer; Claudius Thomé

© The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: [email protected] doi:10.1093/neuonc/now291 Advance Access date 28 February 2017 increase in natural abundance 2H would result in only 1% of protons in fatty acids from the ketogenic diet to be replaced by 2H. The kinetic isotope effect (KIE) as referred to by Boros et al would reduce rates of enzymatic reactions breaking carbon-deuterium bonds. As such, the presumed high deuterium content of our ketogenic diet as suggested by Boros et al would slow down ketone body metabolism via KIEs on ketolytic enzymes yet also produce deuterated metabolic water. The extent of ketone body metabolism is exactly what we measured in vivo with 13C MR spectroscopy. In contrast to what Boros et al suggest, the relative rate of ketone body oxidation was similar between tumorous and nontumorous brain tissue, and was increased when animals were put on the ketogenic diet (Supplementary Table 2).1 Interestingly, if the level of the elusive deuterated water was indeed high, if anything it could have had a tumor growth–inhibiting effect, as observed by Rodrigues et al after providing 50% (v/v) H2O for 9 days in glioma-bearing rats (which is several orders of magnitude above the 2H enrichment anticipated from a diet with slightly increased 2H content).2

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Claudius Thomé

Innsbruck Medical University

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Daniel Pinggera

Innsbruck Medical University

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Astrid E. Grams

Innsbruck Medical University

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Konstantin Brawanski

Innsbruck Medical University

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Martha Nowosielski

Innsbruck Medical University

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Martin Ortler

Innsbruck Medical University

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Ondra Petr

Innsbruck Medical University

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