[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE The purpose of this research was to examine the stability of long-term hearing preservation and the regeneration capacity of the cochlear nerve following vestibular schwannoma (VS) surgery in a prospective study. METHODS A total of 112 patients were recruited for a randomized multicenter trial between January 2010 and April 2012 to investigate the efficacy of prophylactic nimodipine treatment versus no prophylactic nimodipine treatment in VS surgery. For the present investigation, both groups were pooled to compare hearing abilities in the early postoperative course and 1 year after the surgery. Hearing was examined using pure-tone audiometry with speech discrimination, which was performed preoperatively, in the early postoperative course, and 12 months after surgery and was subsequently classified by an independent otorhinolaryngologist using the Gardner-Robertson classification system. RESULTS Hearing abilities at 2 time points were compared by evaluation in the early postoperative course and 1 year after surgery in 102 patients. The chi-square test showed a very strong association between the 2 measurements in all 102 patients (p < 0.001) and in the subgroup of 66 patients with a preserved cochlear nerve (p < 0.001). CONCLUSIONS There is no significant change in cochlear nerve function between the early postoperative course and 1 year after VS surgery. The result of hearing performance, as evaluated by early postoperative audiometry after VS surgery, seems to be a reliable prognosticator for future hearing ability. Clinical trial registration nos.: 2009-012088-32 ( clinicaltrialsregister.eu ) and DRKS 00000328 ("AkNiPro," drks-neu.uniklinik-freiburg.de/drks_web/ ).
Full-text · Article · Jan 2016 · Journal of Neurosurgery
[Show abstract][Hide abstract] ABSTRACT: Background
The study was conducted to clarify the presence or absence of fronto-temporal branches (FTB) of the facial nerve within the interfascial (between the superficial and deep leaflet of the temporalis fascia) fat pad.
Eight formalin-fixed cadaveric heads (16 sides) were used in the study. The course of the facial nerve and the FTB was dissected in its individual tissue planes and followed from the stylomastoid foramen to the frontal region.
In the fronto-temporal region, above the zygomatic arch, FTB gives several small twigs running anteriorly in the fat pad above the superficial temporalis fascia and a branch within the temporo-parietal fascia (TPF) to the muscles of the forehead. There were no twigs of the FTB within the interfascial fat pad.
No branches of the FTB are found in the interfascial (between the superficial and deep leaflet of the temporalis fascia) fat pad. The interfascial dissection can be safely performed without risk of injury to the FTB and potential subsequent frontalis palsy.
No preview · Article · Jan 2016 · Acta Neurochirurgica
[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE The authors' aim in this paper is to prove the feasibility of resting-state (RS) functional MRI (fMRI) in an intraoperative setting (iRS-fMRI) and to correlate findings with the clinical condition of patients pre- and postoperatively. METHODS Twelve patients underwent intraoperative MRI-guided resection of lesions in or directly adjacent to the central region and/or pyramidal tract. Intraoperative RS (iRS)-fMRI was performed pre- and intraoperatively and was correlated with patients' postoperative clinical condition, as well as with intraoperative monitoring results. Independent component analysis (ICA) was used to postprocess the RS-fMRI data concerning the sensorimotor networks, and the mean z-scores were statistically analyzed. RESULTS iRS-fMRI in anesthetized patients proved to be feasible and analysis revealed no significant differences in preoperative z-scores between the sensorimotor areas ipsi- and contralateral to the tumor. A significant decrease in z-score (p < 0.01) was seen in patients with new neurological deficits postoperatively. The intraoperative z-score in the hemisphere ipsilateral to the tumor had a significant negative correlation with the degree of paresis immediately after the operation (r = -0.67, p < 0.001) and on the day of discharge from the hospital (r = -0.65, p < 0.001). Receiver operating characteristic curve analysis demonstrated moderate prognostic value of the intraoperative z-score (area under the curve 0.84) for the paresis score at patient discharge. CONCLUSIONS The use of iRS-fMRI with ICA-based postprocessing and functional activity mapping is feasible and the results may correlate with clinical parameters, demonstrating a significant negative correlation between the intensity of the iRS-fMRI signal and the postoperative neurological changes.
No preview · Article · Jan 2016 · Journal of Neurosurgery
[Show abstract][Hide abstract] ABSTRACT: Xiao and colleagues in China reported successful restoration of bladder control in patients with spinal cord injury (SCI) by establishing a somatic-autonomic reflex pathway through lumbar-to-sacral ventral root nerve rerouting. We evaluated long-term results in eight patients who underwent this procedure at a German university clinic between 2005 and 2007. The primary outcome was the occurrence of voiding upon stimulation of the skin, with normalization of bladder pressure when filling, as assessed with videourodynamics at each visit. Videourodynamic variables, urinary tract infections, and bladder/stool events recorded in a patient diary were stored in a prospective database and reviewed retrospectively. Intraoperative testing indicated successful nerve rerouting in all eight patients. Duration of follow-up was 71 mo (range: 56–86). No patient reached the primary goal of voluntary voiding with normalization of detrusor pressure at any point during follow-up. No improvements in videourodynamic or diary variables regarding bladder function were observed. In view of the lack of short (12–18 mo) and long-term (71 mo) success in our patients and others, the risks of any surgical procedure using general anesthesia, and potential for unmet expectations to wreak havoc on patient emotional well-being, we cannot recommend this procedure for patients with SCI.
No preview · Article · Dec 2015 · European Urology
[Show abstract][Hide abstract] ABSTRACT: Rationale and objectives:
Resting-state (RS) networks, revealed by functional magnetic resonance imaging (fMRI) studies in healthy volunteers, have never been evaluated in anesthetized patients with brain tumors. Our purpose was to examine the presence of residual brain activity on the auditory network during propofol-induced loss of consciousness in patients with brain tumors.
Materials and methods:
Twenty subjects with intracranial masses were prospectively studied by means of intraoperative RS-fMRI acquisitions before any craniectomy. After performing single-subject independent component analysis, spatial maps and time courses were assigned to an auditory RS network template from the literature and compared via spatial regression coefficients.
All fMRI data were of sufficient quality for further postprocessing. In all but two patients, the RS functional activity of the auditory network could be successfully mapped. In almost all patients, contralateral activation of the auditory network was present. No significant difference was found between the mean distance of the RS activity clusters and the lesion periphery for tumors located in the temporal gyri vs. those in other brain regions. The spatial deviation between the activated cluster in our experiment and the template was significantly (P = 0.04) higher in patients with tumors located in the temporal gyri than in patients with tumors located in other regions.
Propofol-induced anesthesia in patients with intracranial lesions does not alter the blood-oxygenation level-depended signal, and independent component analysis of intraoperative RS-fMRI may allow assessment of the auditory network in a clinical setting.
No preview · Article · Nov 2015 · Academic radiology
[Show abstract][Hide abstract] ABSTRACT: Background:
The ideal treatment strategy for low-grade gliomas (LGGs) is a controversial topic. Additionally, only smaller single-center series dealing with the concept of intraoperative magnetic resonance imaging (iMRI) have been published.
To investigate determinants for patient outcome and progression-free-survival (PFS) after iMRI-guided surgery for LGGs in a multicenter retrospective study initiated by the German Study Group for Intraoperative Magnetic Resonance Imaging.
A retrospective consecutive assessment of patients treated for LGGs (World Health Organization grade II) with iMRI-guided resection at 6 neurosurgical centers was performed. Eloquent location, extent of resection, first-line adjuvant treatment, neurophysiological monitoring, awake brain surgery, intraoperative ultrasound, and field-strength of iMRI were analyzed, as well as progression-free survival (PFS), new permanent neurological deficits, and complications. Multivariate binary logistic and Cox regression models were calculated to evaluate determinants of PFS, gross total resection (GTR), and adjuvant treatment.
A total of 288 patients met the inclusion criteria. On multivariate analysis, GTR significantly increased PFS (hazard ratio, 0.44; P < .01), whereas "failed" GTR did not differ significantly from intended subtotal-resection. Combined radiochemotherapy as adjuvant therapy was a negative prognostic factor (hazard ratio: 2.84, P < .01). Field strength of iMRI was not associated with PFS. In the binary logistic regression model, use of high-field iMRI (odds ratio: 0.51, P < .01) was positively and eloquent location (odds ratio: 1.99, P < .01) was negatively associated with GTR. GTR was not associated with increased rates of new permanent neurological deficits.
GTR was an independent positive prognostic factor for PFS in LGG surgery. Patients with accidentally left tumor remnants showed a similar prognosis compared with patients harboring only partially resectable tumors. Use of high-field iMRI was significantly associated with GTR. However, the field strength of iMRI did not affect PFS.
EoR, extent of resectionFLAIR, fluid-attenuated inversion recoveryGTR, gross total resectionIDH1, XXXiMRI, intraoperative magnetic resonance imagingLGG, low-grade gliomaMGMT, methylguanine-deoxyribonucleic acid methyltransferasenPND, new permanent neurological deficitOS, overall survivalPFS, progression-free survivalSTR, subtotal resectionWHO, World Health Organization.
[Show abstract][Hide abstract] ABSTRACT: Objective:
to compare the anatomical exposure and petrosectomy extent in the Kawase and PIPA approaches.
Kawase and PIPA approaches were performed on 4 fixed cadaveric heads (3 alcohol-fixed, 1 formaldehyde-fixed silicone-injected, 4 Kawase and 4 PIPA approaches). The microsurgical anatomy was examined by means of Zeiss Opmi CS/NC-4® microscopes. HD Karl Storz Endoscopes (AIDA system) were used to display intradural exposure. Petrosectomy volumes was assessed comparing pre- and post-operative thin-slices CT scans (Analyze 12.0, AnalyzeDirect Mayo Clinic).
Kawase approach exposed the rhomboid fossa with Meckel's cave extradurally, the upper half of the clivus, superior cerebellopontine angle, ventro-lateral brainstem, the intrameatal region, basilar apex, the preganglionic root of CN V, CN III-IV-VI intradurally. PIPA approach exposed the cerebello-pontine angle with CN VI-XII, Meckel's cave, CN III-V, the middle and lower clivus intradurally from a posterior view. The area of surgical exposure is wide in both approaches, however, the volume of petrosectomy, the working angle and surgical corridor differ significantly.
Kawase approach allows wide exposure of the MCF and PCF, requiring extradural temporal lobe retraction and an extradural petrosectomy with preservation of the internal acoustic meatus and cochlea. No temporal lobe retraction and direct control of neurovascular structures make the PIPA approach a valid alternative for lesions extending mostly in the PCF with minor extension in the MCF. The longer surgical corridor, cerebellar retraction, and limited exposure of the anterior brainstem make this approach less indicated for lesions with major extension in the MCF and the anterior cavernous sinus.
Full-text · Article · Oct 2015 · World Neurosurgery
[Show abstract][Hide abstract] ABSTRACT: We present the case of a 72-year old female with a right cerebellar pilocytic astrocytoma WHO grade I with an Isocitrate dehydrogenase 1 (IDH1) R132H mutation. The patient is recurrence-free 6 years after the initial diagnosis. Only one single case with strikingly similar clinicopathological features has been reported before. Otherwise, IDH1/2 mutations are not seen in pilocytic astrocytomas. The clinical implications of these findings are discussed.
Full-text · Article · Sep 2015 · International journal of clinical and experimental pathology
[Show abstract][Hide abstract] ABSTRACT: Objective
Antiepileptic treatment of brain tumor patients mainly depends on the individual physician's choice rather than on well-defined predictive factors. We investigated the predictive value of defined clinical parameters to formulate a model of risk estimations for subpopulations of brain tumor patients.Methods
We enclosed 650 patients > 18 years of age who underwent brain tumor surgery and included a number of clinical data. Logistic regressions were performed to determine the effect sizes of seizure related risk factors and to develop prognostic scores for the occurrence of preoperative and early postoperative seizures.ResultsA total of 492 patients (334 gliomas) were eligible for logistic regression for preoperative seizures, and 338 patients for early postoperative seizures. Age ≤60 years (OR 1.66, p=0.020), grades I and II glioma (OR 4.00, p=0.0002), total tumor/edema volume ≤64cm3 (OR 2.18, p=0.0003), and frontal location (OR 2.28, p=0.034) demonstrated an increased risk for preoperative seizures. Isocitrate-dehydrogenase mutations (OR 2.52, p=0.026) were an independent risk factor in the glioma subgroup. Age ≥60 years (OR 3.32, p=0.041), total tumor/edema volume ≤64cm3 mm (OR 3.17, p=0.034), complete resection (OR 15.50, p=0.0009), diencephalic location (OR 12.2, p=0.013), and high-grade tumors (OR 5.67, p=0.013) were significant risk factors for surgery-related seizures. Antiepileptics (OR 1.20, p=0.60) did not affect seizure occurrence. For seizure occurrence, patients could be stratified into three prognostic preoperative and into two prognostic early postoperative groups.InterpretationBased on the developed prognostic scores, seizure prophylaxis should be considered in high-risk patients and patient stratification for prospective studies may be feasible in the future. This article is protected by copyright. All rights reserved.
No preview · Article · Sep 2015 · Annals of Neurology
[Show abstract][Hide abstract] ABSTRACT: OBJECT A pilot study of prophylactic nimodipine and hydroxyethyl starch treatment showed a beneficial effect on facial and cochlear nerve preservation following vestibular schwannoma (VS) surgery. A prospective Phase III trial was undertaken to confirm these results. METHODS An open-label, 2-arm, randomized parallel group and multicenter Phase III trial with blinded expert review was performed and included 112 patients who underwent VS surgery between January 2010 and February 2013 at 7 departments of neurosurgery to investigate the efficacy and safety of the prophylaxis. The surgery was performed after the patients were randomly assigned to one of 2 groups using online randomization. The treatment group (n = 56) received parenteral nimodipine (1-2 mg/hr) and hydroxyethyl starch (hematocrit 30%-35%) from the day before surgery until the 7th postoperative day. The control group (n = 56) was not treated prophylactically. RESULTS Intent-to-treat analysis showed no statistically significant effects of the treatment on either preservation of facial nerve function (35 [67.3%] of 52 [treatment group] compared with 34 [72.3%] of 47 [control group]) (p = 0.745) or hearing preservation (11 [23.4%] of 47 [treatment group] compared with 15 [31.2%] of 48 [control group]) (p = 0.530) 12 months after surgery. Since tumor sizes were significantly larger in the treatment group than in the control group, logistic regression analysis was required. The risk for deterioration of facial nerve function was adjusted nearly the same in both groups (OR 1.07 [95% CI 0.34-3.43], p = 0.91). In contrast, the risk for postoperative hearing loss was adjusted 2 times lower in the treatment group compared with the control group (OR 0.49 [95% CI 0.18-1.30], p = 0.15). Apart from dose-dependent hypotension (p < 0.001), no clinically relevant adverse reactions were observed. CONCLUSIONS There were no statistically significant effects of the treatment. Despite the width of the confidence intervals, the odds ratios may suggest but do not prove a clinically relevant effect of the safe study medication on the preservation of cochlear nerve function after VS surgery. Further study is needed before prophylactic nimodipine can be recommended in VS surgery.
Full-text · Article · Aug 2015 · Journal of Neurosurgery
[Show abstract][Hide abstract] ABSTRACT: Intraoperative magnetic resonance imaging (iMRI) has dramatically expanded and nowadays presents state-of-the-art technique for image-guided neurosurgery, facilitating critical precision and effective surgical treatment of various brain pathologies. Imaging hardware providing basic imaging sequences as well as advanced MRI can be seamlessly integrated into routine surgical environments, which continuously leads to emerging indications for iMRI-assisted surgery. Besides the obvious intraoperative diagnostic yield, the initial clinical benefits have to be confirmed by future-controlled long-term studies.
[Show abstract][Hide abstract] ABSTRACT: Tumor resection in the rolandic region, also known as sensorimotor cortex, is a challenge. This study aims at reviewing a series of patients undergoing resection of metastases in the sensorimotor cortex using a multimodal concept including neuronavigation, sonography, and intraoperative electrophysiological monitoring. Eleven patients suffering from metastases located in precentral (8) and postcentral gyrus (3) were analyzed concerning their functional motor outcome. Improvement of motor function could be seen in 5 patients 1 week after surgery, 5 patients remained unchanged, and only 1 deteriorated. Median survival time averaged 15 months. A multimodal approach, including preoperative and intraoperative neuronavigation, intraoperative sonography, and intraoperative electrophysiological monitoring can lead on to excellent functional outcome in surgery of metastases in the sensorimotor cortex. Copyright
No preview · Article · Jun 2015 · Neurosurgery Quarterly