Two-step staged resection of giant olfactory groove meningiomas.

BACKGROUND: The surgical treatment of giant olfactory groove meningiomas (OGMs) with marked perilesional brain oedema is still a surgical challenge. After tumour resection, increase of brain oedema may occur causing dramatic neurological deterioration and even death of the patient. The objective of this paper is to describe surgical features of a two-step staged resection of these tumours performed to counter increase of postoperative brain oedema. METHODS: This two-step staged resection procedure was carried out in a consecutive series of 19 patients harbouring giant OGMs. As first step, a bifrontal craniectomy was performed followed by a right-sided interhemispherical approach. About 80% of the tumour mass was resected leaving behind a shell-shaped tumour remnant. In the second step, carried out after the patients' recovery from the first surgery and decline of oedema, the remaining part of the tumour was removed completely followed by duro- and cranioplasty. RESULTS: Ten patients recovered quickly from first surgery and the second operation was performed after a mean of 12.4 days. In eight patients, the second operation was carried out later between day 25 and 68 due to surgery-related complications, development of a trigeminal zoster, or to a persisting frontal brain oedema. Mean follow-up was 49.3 months and all but one patient had a good outcome regardless of surgery-related complications. CONCLUSIONS: Our results suggest that a two-step staged resection of giant OGMs minimizes the increase of postoperative brain oedema as far as possible and translates into lower morbidity and mortality.

Predictive variables for the presence of vascular malformations as the cause of basal ganglia hemorrhages.

To evaluate potential bleeding sources and predictive variables for basal ganglia hemorrhage. Fifty-seven patients with basal ganglia hemorrhage admitted to our neurosurgical ICU between 2005 and 2016 were retrospectively reviewed. Univariate and multivariate logistic analyses were used to assess predictive variables for identifying the bleeding source and outcome. ROC curves were plotted for a cutoff value for age and hematoma volume in patients with a vascular pathology and patients without a vascular pathology. In 19 patients, a vascular pathology was found as a bleeding source for basal ganglia hemorrhage (33.3%; 95% CI 0.33 [0.21; 0.47]). Most of the arteriovenous malformations (AVMs) were small sized (61.1%) with deep venous drainage (94.4%). A single vein was found in 17 (77.8%) AVMs. Patients younger than 50 years were more likely to have a vascular pathology (AUC of 0.85 [95% CI 0.73; 0.98]; p = 0.001; cutoff value 46.5 years). Four (21.1%) patients older than 50 years suffered an AVM hemorrhage; 75% of them were located ventricular or thalamic. Hematoma volume in patients with AVM hemorrhage was predominantly less than 30 cm3 (AUC of 0.86 [95% CI 0.76; 0.96]; p = 0.001; cutoff value 12.6 cm3). Outcome in patients with a vascular pathology was more often favorable as in patients with a spontaneous hemorrhage (92.9% vs. 7.1%; p = 0.001). Young age and hematoma volume are significant predictors for presence of a bleeding source and outcome in basal ganglia hemorrhage. These criteria must be taken into account in the emergency diagnostics and therapy in order to achieve a rapid and sufficient result. Outcome in patients with AVM hemorrhage in basal ganglia is more often favorable.

First clinical experience with the new noninvasive transfontanelle ICP monitoring device in management of children with premature IVH.

We previously introduced a novel noninvasive technique of intracranial pressure (ICP) monitoring in children with open fontanelles. Within this study, we describe the first clinical implementation and results of this new technique in management of children with hydrocephalus caused by intraventricular hemorrhage (IVH). In neonates with posthemorrhagic hydrocephalus (PHH), an Ommaya reservoir was implanted for initial treatment of hydrocephalus. The ICP obtained noninvasively with our new device was measured before and after CSF removal and correlated to cranial ultra-sonographies. Six children with a mean age of 27.3 weeks and mean weight of 1082.3 g suffering from PHH were included in this study. We performed an overall of 30 aspirations due to ventricular enlargement. Before CSF removal, the mean ICP was 15.3 mmHg and after removal of CSF the mean ICP measured noninvasively decreased to 3.4 mmHg, p = 0.0001. The anterior horn width (AHW), which reflects early expansion of the ventricles, was before and after CSF removal 15.1 mm and 5.5 mm, respectively, p < 0.0006. There was a strong correlation between noninvasively measured ICP values and sonographically obtained AHW, r = 0.81. Ultimately, all children underwent ventriculoperitoneal shunt procedures. This is the first study providing proof for a noninvasively ICP-based approach for management of posthemorrhagic hydrocephalus in newborn children.

Cerebral Vasospasm Due to Arteriovenous Malformation-Associated Hemorrhage: Impact of Bleeding Source and Pattern.

OBJECTIVE: Cerebral vasospasm (CVS) after a ruptured arteriovenous malformation (AVM) is rarely reported. This study is aimed at evaluating the predictive variables in AVM hemorrhage for CVS. METHODS: A total of 160 patients with ruptured AVMs were admitted to our neurosurgical department from 2002 to 2018. The frequency of cerebral vasospasm after AVM hemorrhage and the impact of AVM-associated aneurysms were evaluated. We compared different bleeding patterns, such as intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH) or a combination of both (ICH + SAH) and evaluated predictive variables for outcome in last follow-up. RESULTS: A total of 62 (39%) patients had AAA, mostly located prenidal (75.8%). AVMs with ruptured aneurysms often resulted in ICH with SAH component (p < 0.001). Eighty-two patients (51%) presented a SAH component, and CVS occurred in 6 patients (7.3%), mostly due to a ruptured infratentorial AVM (p < 0.03). Infratentorial location and the amount of SAH component (p < 0.001) predicted the incidence of CVS significantly. Cerebral infarction was significantly associated with CVS (p < 0.02). CONCLUSION: SAH component and infratentorial location of ruptured AVMs may harbor a higher risk for CVS. Follow-up with angiographic imaging should be considered in patients with infratentorial AVM hemorrhage and delayed neurologic deterioration to rule out CVS.

Prognostic variables and outcome in relation to different bleeding patterns in arteriovenous malformations.

Subarachnoid hemorrhage as bleeding pattern occurs rarely in ruptured arteriovenous malformations (AVM). The aim of the present study is to evaluate different bleeding patterns in hemorrhages due to an AVM and their impact on outcome in terms of risk and treatment stratification. We evaluated 158 patients with ruptured AVMs who were admitted to our neurosurgical department from 2002 to 2017. We compared different bleeding patterns, such as intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH), or both (ICH + SAH) and evaluated predictive variables for outcome in the last follow-up. ICH was found in 48.7% of patients, isolated SAH in 20.9% of patients, and both in 30.4% of patients. The mean parenchymal blood volume was 34.5cm3. 38.6% of the patients had AVM-associated aneurysms, mostly located pre-nidal (77%). AVMs with ruptured aneurysms often resulted in ICH with SAH component (p < 0.001) and SAH pattern occurred more often infratentorial (p = 0.003). In a multivariate logistic regression model, poor clinical state on admission (WFNS IV-V) (p < 0.01), eloquence, infratentorial location (p = 0.05), and presence of ICH with SAH component (p = 0.02) were the most relevant predictors of a poor outcome after AVM rupture. Bleeding pattern in AVM hemorrhage depends on angioarchitectural and hemodynamic features and SAH component predicts outcome negatively. AVM-associated pre-nidal aneurysms may harbor a higher risk for rupture and SAH pattern when located infratentorial. Treatment decisions and risk stratifications should be considered in view of these findings.

Academic output of German neurosurgical residents in 35 academic neurosurgery residency programs.

BACKGROUND: The scientific activity of neurosurgeons and neurosurgery residents as measured by bibliometric parameters is of increased interest. While data about academic output for neurosurgeons in the USA, the UK, and Canada have been published, no similar results for German neurosurgical residents exist. Within this study, we aim to evaluate the academic output of German neurosurgery residents in 35 academic residency programs. METHODS: Data for each resident were collected from the departmental websites, Pubmed, and Scopus. Further analyses evaluated the relationship between publication productivity, sex, and academic degree (Dr. med.). RESULTS: Data from 424 neurosurgery residents were analyzed. A total of 1222 publications were considered. A total of 355 (29%) of the 1222 publications were first-author publications. The average number of publications per resident was 2.9; the average h-index and m-quotient was 1.1 and 0.4, respectively. There was a statistically significant difference in academic output and h-index among neurosurgical residents with a doctoral degree compared with residents without such degree (5.3 vs. 1.3, p < 0.0001 and 2.0 vs. 0.5, p < 0.0001). CONCLUSION: This is the very first study evaluating the academic output of neurosurgical residents in academic neurosurgical departments in Germany.

Dexamethasone-induced leukocytosis is associated with poor survival in newly diagnosed glioblastoma.

Despite its well-characterized side effects, dexamethasone is widely used in the pre-, peri- and postoperative neurosurgical setting due to its effective relief of tumor-induced symptoms through the reduction of tumor-associated edema. However, some patients show laboratory-defined dexamethasone induced elevation of white blood cell count, and its impact on glioblastoma progression is unknown. We retrospectively analyzed 113 patients with newly diagnosed glioblastoma to describe the incidence, risk factors and clinical features of dexamethasone-induced leukocytosis in primary glioblastoma patients. We further conducted an immunohistochemical analysis of the granulocyte and lymphocyte tumor-infiltration in the available corresponding histological sections. Patient age was identified to be a risk factor for the development of dexamethasone-induced leukocytosis (p < 0.05). The presence of dexamethasone-induced leukocytosis decreased overall survival (HR 2.25 95% CI [1.15-4.38]; p < 0.001) and progression-free survival (HR 2.23 95% CI [1.09-4.59]; p < 0.01). Furthermore, patients with dexamethasone-induced leukocytosis had significantly reduced CD15 + granulocytic- (p < 0.05) and CD3 + lymphocytic tumour infiltration (p < 0.05). We identified a subgroup of glioblastoma patients that are at particularly high risk for poor outcome upon dexamethasone treatment. Therefore, restrictive dosage or other edema reducing substances should be considered in patients with dexamethasone-induced leukocytosis.

Pre- and early postoperative GFAP serum levels in glioma and brain metastases.

SUBJECT: To date there is no established tumor marker for the clinical follow-up of glioblastoma, WHO grade IV, (GBM) which constitutes the most frequent and malignant primary brain tumor. However, since there is promising data that the serum glial fibrillary acidic protein (sGFAP) may serve as a biomarker for glial brain tumors, this prospective study aimed at evaluating the diagnostic relevance of perioperative changes in sGFAP levels for the assessment of residual glial tumor tissue in patients undergoing surgery of intracerebral tumors. METHODS: Serum GFAP was measured using an electrochemiluminometric immunoassay (ElecsysR GFAP prototype test, Roche Diagnostics, Penzberg/Germany) in 32 prospectively recruited patients between September 2009 and August 2010. Twenty-five were diagnosed with glioma and seven with brain metastases (BM). We assessed sGFAP levels prior to and at different time points during the early postoperative phase until patient discharge. RESULTS: There were only significant differences in the pre-operative sGFAP levels of patients with gliomas compared to BM (0.18 vs. 0.08 µg/l; p = 0.0198, Welch's t-Test). Even though there was an increase of sGFAP after surgery, there were no significant differences between glioma and BM patients at any other time point. Peak sGFAP levels where reached on postoperative day 1 followed by a slight decrease, but not reaching pre-operative levels until postop day 7. There was no significant correlation between postoperative glioma tumor volume and sGFAP levels in univariate analyses. CONCLUSION: According to our data sGFAP does not appear to be suitable to detect residual glioma tissue in the acute postoperative phase.

Stereotactic biopsy of cerebellar lesions: straight versus oblique frame positioning.

OBJECTIVE: Biospies of brain lesions with unknown entity are an everyday procedure among many neurosurgical departments. Biopsies can be performed frame-guided or frameless. However, cerebellar lesions are a special entity with a more complex approach. All biopsies in this study were performed stereotactically frame guided. Therefore, only biopsies of cerebellar lesions were included in this study. We compared whether the frame was attached straight versus oblique and we focused on diagnostic yield and complication rate. METHODS: We evaluated 20 patients who underwent the procedure between 2009 and 2017. Median age was 56.5 years. 12 (60%) Patients showed a left sided lesion, 6 (30%) showed a lesion in the right cerebellum and 2 (10%) patients showed a midline lesion. RESULTS: The stereotactic frame was mounted oblique in 12 (60%) patients and straight in 8 (40%) patients. Postoperative CT scan showed small, clinically silent blood collection in two (10%) of the patients, one (5%) patient showed haemorrhage, which caused a hydrocephalus. He received an external ventricular drain. In both patients with small haemorrhage the frame was positioned straight, while in the patient who showed a larger haemorrhage the frame was mounted oblique. In all patients a final histopathological diagnosis was established. CONCLUSION: Cerebellar lesions of unknown entity can be accessed transcerebellar either with the stereotactic frame mounted straight or oblique. Also for cerebellar lesions the procedure shows a high diagnostic yield with a low rate of severe complications, which need further treatment.

Intratumoral Concentrations and Effects of Orally Administered Micellar Curcuminoids in Glioblastoma Patients.

BACKGROUND: The oral bioavailability of curcuminoids is low, but can be enhanced by incorporation into micelles. The major curcuminoid curcumin has antitumor effects on glioblastoma cells in vitro and in vivo. We therefore aimed to determine intratumoral concentrations and the clinical tolerance of highly bioavailable micellar curcuminoids in glioblastoma patients. METHODS: Thirteen glioblastoma patients ingested 70 mg micellar curcuminoids [57.4 mg curcumin, 11.2 mg demethoxycurcumin (DMC), and 1.4 mg bis-demethoxycurcumin (BDMC)] three times per day for 4 days (total amount of 689 mg curcumin, 134 mg DMC, and 17 mg BDMC) prior to planned resection of their respective brain tumors. Tumor and blood samples were taken during the surgery and analyzed for total curcuminoid concentrations. (31)P magnetic resonance spectroscopic imaging was performed before and after curcuminoid consumption. RESULTS: Ten patients completed the study. The mean intratumoral concentration of curcumin was 56 pg/mg of tissue (range 9-151), and the mean serum concentration was 253 ng/ml (range 129-364). Inorganic phosphate was significantly increased within the tumor (P = 0.034). The mean ratio of phosphocreatine to inorganic phosphate decreased, and the mean intratumoral pH increased (P = 0.08) after curcuminoid intervention. CONCLUSION: Oral treatment with micellar curcuminoids led to quantifiable concentrations of total curcuminoids in glioblastomas and may alter intratumoral energy metabolism.

Stereotactic biopsy of brainstem lesions: 21 years experiences of a single center.

Stereotactic biopsies are procedures performed to obtain tumor tissue for diagnostic examinations. Cerebral lesions of unknown entities can safely be accessed and tissue can be examined, resulting in correct diagnosis and according treatment. Stereotactic procedures of lesions in highly eloquent regions such as the brainstem have been performed for more than two decades in our department. In this retrospective study we focus on results, approaches, modalities of anesthesia, and complications. We performed a retrospective analysis of our prospective database, including 26 patients who underwent stereotactic biopsy of the brainstem between April 1994 and June 2015. All of the patients underwent preoperative MRI. Riechert-Mundinger-frame was used before 2000, thereafter the Leksell stereotactic frame was used. After 2000 entry and target points were calculated by using BrainLab stereotactic system. We evaluated histopathological results as well as further treatment; additionally we compared complications of local versus general anesthesia and complications of a frontal versus a trans-cerebellar approach. Median age of all patients was 33 years, and median number of tissue samples taken was 12. In all patients a final histopathological diagnosis could be established. 5 patients underwent the procedure under local anesthesia, 21 patients in general anesthesia. In 19 patients a frontal approach was performed, while in 7 patients a trans-cerebellar approach was used. Complications occurred in five patients. Thereby no significant difference was found with regard to approach (frontal versus trans-cerebellar) or anesthesia (local versus general). Stereotactic biopsies even of lesions in the brainstem are a save way to obtain tumor tissue for final diagnosis, resulting in adequate treatment. Approach can be trans-cerebellar or frontal and procedure can be performed either under local or general anesthesia without significant differences concerning complication rate.

Combination of 5-ALA and iMRI in re-resection of recurrent glioblastoma.

Background Tumour resection plays a role in the initial treatment but also in the setting of recurrent glioblastoma (rGBM). To achieve maximum resection, 5-aminolevulinic acid (5-ALA) and intraoperative MRI (iMRI) are used as surgical tools. Aiming at complete tumour re-resection, we started combining iMRI with 5-ALA to find out if this leads to better surgical results. Methods We performed tumour resections in seven patients with rGBM, combining 5-ALA (20 mg/kg bodyweight) with iMRI (0.15 T). Radiologically complete resections were intended in all seven patients. We assessed intraoperative fluorescence findings and compared these with intraoperative imaging. All patients had early postoperative MRI (3 T) to verify final iMRI scans and received adjuvant treatment according to interdisciplinary tumour board decision. Results Median patient age was 63 years. Median KPS score was 90, and median tumour volume was 8.2 cm(3). In six of seven patients (85%), 5-ALA induced fluorescence of tumour-tissue was detected intraoperatively. All tumours were good to visualise with iMRI and contrast media. One patient received additional resection of residual contrast enhancing tissue on intraoperative imaging, which did not show fluorescence. Radiologically complete resections according to early postoperative MRI were achieved in all patients. Median survival since second surgery was 7.6 months and overall survival since diagnosis was 27.8 months. Conclusions 5-ALA and iMRI are important surgical tools to maximise tumour resection also in rGBM. However, not all rGBMs exhibit fluorescence after 5-ALA administration. We propose the combined use of 5-ALA and iMRI in the surgery of rGBM.

Increased Body Mass Index Correlates with Less Favorable Postoperative Outcomes After Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea: A Retrospective Cohort Study.

OBJECTIVE: Obstructive sleep apnea is associated with high morbidity. Hypoglossal nerve stimulation (HNS) has become a novel (neuro-) surgical treatment strategy for obstructive sleep apnea, demonstrating good success rates. Beyond predefined inclusion and exclusion criteria, no precise data are available, enabling individual preoperative risk assessment. To improve preoperative risk stratification, this study analyzed individual patient factors that affect outcomes of HNS. METHODS: Fourteen patients treated with unilateral HNS were analyzed retrospectively. Assessed risk factors included: hypertension, diabetes mellitus, depression, smoking, alcohol consumption, body mass index (BMI), and disease duration. Treatment success was defined as a reduction in the postoperative apnea-hypopnea index (AHI) to ≤20 events/hour, with a relative reduction of at least 50% compared to baseline. RESULTS: A significant reduction in the postoperative apnea-hypopnea index was observed in all patients (P < 0.0001). BMI correlated significantly with postoperative AHI scores (95% confidence interval, 0.1519-0.8974; P = 0.018). Significant treatment success was observed in 50% of patients. Compared with the "Excellent Responder group," the "Responder group" demonstrated a significantly higher BMI (95% confidence interval, 1.174-6.226; P = 0.0078). Diabetes, hypertension, disease duration, smoking, depression, and alcohol consumption were not significantly associated with AHI reduction. CONCLUSIONS: Our findings suggest that BMI may be an independent risk factor for the response to HNS, with patients who had less benefit from therapy having significantly higher BMI than "Excellent Responders." Therefore, carefully selecting patients is crucial in obtaining optimal outcomes with HNS therapy, especially those with a high BMI.

Necessity of MRI-compatible deep brain stimulation systems - Hits and hints for decision making.

OBJECTIVES: Deep brain stimulation (DBS) is a safe and effective treatment option for patients with movement disorders as Parkinson's disease, essential tremor and dystonia[1]. For many of these patients the need for imaging may arise in the following years after implantation. The study's aim was to get an overview of the amount of patients with a DBS system who needed an MRI after successful implantation, and if they did, whether the imaging led to a surgical consequence. MATERIALS AND METHODS: In this retrospective descriptive work patients were included if they had their DBS implantation for at least 12 months at the time of analysis. Data were collected by retrospective analysis of the electronic patient files as well as a telephone interview. The reason of each imaging performed was assessed, if patients got MRI after the implantation, it was additionally recorded whether imaging led to a consequence (conservative treatment or surgery). An independent neurologist assessed if an MRI would have been better than a CT for the particular indication. RESULTS: From 54 included patients, 28 patients received imaging after implantation, either CT or MRI. 7 patients underwent MRIs, of whom 3 patients received cranial MRIs and 4 patients received lumbar spine MRIs. All cranial MRIs led to conservative therapy, in 2 lumbar MRIs the diagnosis led to surgery. Nearly 13 % of the imaging performed in our study population occurred because of fall events, 9 of the included patients developed or have had a tumor diagnosis. CONCLUSIONS: Safety of MRI for patients with implanted DBS-systems is and remains an important consideration. Since it can be assumed that patients at a younger age are more likely to get an MRI in the course of their disease, we suggest paying particular attention to the MRI's suitability of the DBS device by patients age. In the end it remains always an individual decision for the surgeon or the consulting physician, which system to use.

Tissue expansion for challenging DBS hardware erosions in patients with Parkinson's disease.

•Consider tissue expanders for challenging DBS cases in PD patients with hardware erosion.•Placement of tissue expander is essential in planning the reconstruction.•MRI-compatibility of the tissue expander is paramount for shortening the total duration of anesthesia.•Role of routine skin biopsies to identify PD patients at additional risk for developing scalp defects should be investigated.

Motor evoked potentials versus Macrostimulation in predicting the postoperative motor threshold in STN Deep brain stimulation.

INTRODUCTION: Accuracy is crucial in Deep Brain Stimulation (DBS). Electrophysiological and image-based techniques are used to avoid suboptimal positioning. Macrostimulation is the gold standard to delineate the therapeutic window intraoperatively. Despite this, electrode revision rates due to malpositioning are as high as 17%. The goal was to compare motor evoked potentials (MEPs) with the gold standard of Macrostimulation. We assessed accuracy and precision as well as the correlation in predicting motor side effects at the initial mapping 4 weeks postoperatively. METHODS: In this prospective study intraoperative MEPs from 94 contacts in 16 patients undergoing STN DBS under local anesthesia were correlated to the postoperative threshold for stimulation-induced motor side effects and compared to intraoperative Macrostimulation. Analysis of accuracy, precision and correlation (Pearson) was performed. RESULTS: MEPs of the upper extremity had a mean percentage error of 25% (SD 38.8%) and correlated significantly with the motor threshold at postoperative mapping (R=0.235). Macrostimulation was less accurate and precise with a mean percentage error of - 68% (SD 78.8%) but had a higher correlation (R=0.388). MEPs rarely (3%) overestimated the threshold by maximally 1 mA. In contrast, Macrostimulation overestimated the threshold by over 1 mA in 69% leading to a false sense of security. CONCLUSION: MEPs are feasible in an awake setting during Deep Brain Stimulation in the STN for PD patients. MEPs of the upper extremity are more accurate and precise predicting the motor threshold and avoid a false sense of security in comparison to the gold standard of Macrostimulation.

Comparison of frame-less robotic versus frame-based stereotactic biopsy of intracranial lesions.

OBJECTIVE: Robotic guidance might be an alternative to classic stereotaxy for biopsies of intracranial lesions. Both methods were compared regarding time efficacy, histopathological results and complications. METHODS: A retrospective analysis enrolling all patients undergoing robotic- or stereotactic biopsies between 01/2015 and 12/2018 was conducted. Trajectory planning was performed on magnetic resonance imaging (MRI). With the Robotic Surgery Assistant (ROSA), patient registration was accomplished using a facial laser scan in the operating room (OR), immediately followed by biopsy. In stereotaxy, patients were transported to the CT for Leksell Frame registration, followed by biopsy in the OR. RESULTS: The average overall procedure time amounted in robotics to 169 min and in stereotaxy to 179 min (p = 0.005). The difference was greatest for temporal targets, amounting in robotics to 161 min and in stereotaxy to 188 min (p = 0,0007). However, the average time spent purely in the OR amounted in robotics to 140 min and in stereotaxy to 113 min (p < 0.001). In 150 robotic biopsies, diagnostic yield amounted to 98%, in 266 stereotactic biopsies to 91%. Symptomatic postoperative hemorrhages were observed in 3 patients (2%) in robotic biopsy and 7 patients (2,7%) in stereotactic biopsy. CONCLUSION: Robotics showed a shorter overall procedure time as there is no need for a transport to the CT whereas the pure OR time was shorter in stereotaxy due to skipping the laser registration process. Diagnostic yield was higher in robotics, most likely due to case selection, complication rates were equal.

Matching Quantitative MRI Parameters with Histological Features of Treatment-Naïve IDH Wild-Type Glioma.

Quantitative MRI allows to probe tissue properties by measuring relaxation times and may thus detect subtle changes in tissue composition. In this work we analyzed different relaxation times (T1, T2, T2* and T2') and histological features in 321 samples that were acquired from 25 patients with newly diagnosed IDH wild-type glioma. Quantitative relaxation times before intravenous application of gadolinium-based contrast agent (GBCA), T1 relaxation time after GBCA as well as the relative difference between T1 relaxation times pre-to-post GBCA (T1rel) were compared with histopathologic features such as the presence of tumor cells, cell and vessel density, endogenous markers for hypoxia and cell proliferation. Image-guided stereotactic biopsy allowed for the attribution of each tissue specimen to its corresponding position in the respective relaxation time map. Compared to normal tissue, T1 and T2 relaxation times and T1rel were prolonged in samples containing tumor cells. The presence of vascular proliferates was associated with higher T1rel values. Immunopositivity for lactate dehydrogenase A (LDHA) involved slightly longer T1 relaxation times. However, low T2' values, suggesting high amounts of deoxyhemoglobin, were found in samples with elevated vessel densities, but not in samples with increased immunopositivity for LDHA. Taken together, some of our observations were consistent with previous findings but the correlation of quantitative MRI and histologic parameters did not confirm all our pathophysiology-based assumptions.

Resection of central nervous system lymphoma: a paradigm shift?

Central nervous system lymphomas (CNSL) are traditionally regarded as non-surgically treated tumors with a poor prognosis. Usually, only stereotactic biopsy is performed to establish the diagnosis, and most patients show disease progression within half a year. A recent study questioned this view, since patients who had surgical resection of CNSL manifestations prior to adjuvant therapy reportedly had a better outcome than patients who had biopsy only. We performed a retrospective analysis of our patient database to identify patients with CNSL who had undergone "accidental" tumor removal in our department between 2002 and 2013. Four patients had CNSL specific therapy following surgery. One patient received no further therapy because of his bad clinical status. Five patients with CNSL were treated surgically. Three patients were in complete remission at nine, thirteen and 45 months postoperatively, while two others had disease progression at 45 months, respectively. The median survival was 22.6 months. Gross total removal of CNSL may improve outcome. We present a series of five patients who had surgical resection of CNSL. While the importance of chemotherapy is beyond doubt, more data on the effect of surgery on the prognosis of patients with CNSL are needed. However, the paradigm of medical treatment only for CNSL is being challenged.

Pre- and Post-Surgical Dysphagia in Adults with Tumors of the Posterior Fossa: A Prospective Blinded Study.

BACKGROUND: While swallowing disorders are frequent sequela following posterior fossa tumor (PFT) surgery in children, data on dysphagia frequency, severity, and outcome in adults are lacking. The aim of this study was to investigate dysphagia before and after surgical removal of PFT. Additionally, we tried to identify clinical predictors for postsurgical swallowing disorders. Furthermore, this study explored the three-month outcome of dysphagic patients. METHODS: In a cohort of patients undergoing PFT surgery, dysphagia was prospectively assessed pre- and postoperatively using fiberoptic endoscopic evaluation of swallowing. Patients with severe dysphagia at discharge were re-evaluated after three months. Additionally, clinical and imaging data were collected to identify predictors for post-surgical dysphagia. RESULTS: We included 26 patients of whom 15 had pre-operative swallowing disorders. After surgery, worsening of pre-existing dysphagia could be noticed in 7 patients whereas improvement was observed in 2 and full recovery in 3 subjects. New-onset dysphagia after surgery occurred in a minority of 3 cases. Postoperatively, 47% of dysphagic patients required nasogastric tube feeding. Re-evaluation after three months of follow-up revealed that all dysphagic patients had returned to full oral intake. CONCLUSION: Dysphagia is a frequent finding in patients with PFT already before surgery. Surgical intervention can infer a deterioration of impaired swallowing function placing affected patients at temporary risk for aspiration. In contrast, surgery can also accomplish beneficial results resulting in both improvement and full recovery. Overall, our findings show the need of early dysphagia assessment to define the safest feeding route for the patient.