The Alcatraz-Strategy: a roadmap to break the connectivity barrier in malignant brain tumours.

In recent years, the discovery of functional and communicative cellular tumour networks has led to a new understanding of malignant primary brain tumours. In this review, the authors shed light on the diverse nature of cell-to-cell connections in brain tumours and propose an innovative treatment approach to address the detrimental connectivity of these networks. The proposed therapeutic outlook revolves around three main strategies: (a) supramarginal resection removing a substantial portion of the communicating tumour cell front far beyond the gadolinium-enhancing tumour mass, (b) morphological isolation at the single cell level disrupting structural cell-to-cell contacts facilitated by elongated cellular membrane protrusions known as tumour microtubes (TMs), and (c) functional isolation at the single cell level blocking TM-mediated intercellular cytosolic exchange and inhibiting neuronal excitatory input into the malignant network. We draw an analogy between the proposed therapeutic outlook and the Alcatraz Federal Penitentiary, where inmates faced an impassable sea barrier and experienced both spatial and functional isolation within individual cells. Based on current translational efforts and ongoing clinical trials, we propose the Alcatraz-Strategy as a promising framework to tackle the harmful effects of cellular brain tumour networks.

Synchronous versus metachronous spinal metastasis: a comparative study of survival outcomes following neurosurgical treatment.

PURPOSE: Patients with spinal metastases (SM) from solid neoplasms typically exhibit progression to an advanced cancer stage. Such metastases can either develop concurrently with an existing cancer diagnosis (termed metachronous SM) or emerge as the initial indication of an undiagnosed malignancy (referred to as synchronous SM). The present study investigates the prognostic implications of synchronous compared to metachronous SM following surgical resection. METHODS: From 2015 to 2020, a total of 211 individuals underwent surgical intervention for SM at our neuro-oncology facility. We conducted a survival analysis starting from the date of the neurosurgical procedure, comparing those diagnosed with synchronous SM against those with metachronous SM. RESULTS: The predominant primary tumor types included lung cancer (23%), prostate cancer (21%), and breast cancer (11.3%). Of the participants, 97 (46%) had synchronous SM, while 114 (54%) had metachronous SM. The median overall survival post-surgery for those with synchronous SM was 13.5 months (95% confidence interval (CI) 6.1-15.8) compared to 13 months (95% CI 7.7-14.2) for those with metachronous SM (p = 0.74). CONCLUSIONS: Our findings suggest that the timing of SM diagnosis (synchronous versus metachronous) does not significantly affect survival outcomes following neurosurgical treatment for SM. These results support the consideration of neurosurgical procedures regardless of the temporal pattern of SM manifestation.

Image Guided Intraoperative Radiation Therapy After Surgical Resection of Brain Metastases: A First In-Human Feasibility Report.

Purpose: A correct placement of the applicator during intraoperative radiation therapy for brain metastasis is of paramount importance, to deliver a precise and safe treatment. The applicator-to-surface contact assessment cannot be performed under direct observation because the applicator itself limits the visual range. No image guided verification is currently performed intracranially. We hypothesize that image guided intraoperative radiation therapy would assure a more precise delivery in the target area. We describe our workflow in a first in-human experience. Methods and Materials: Phantom-based measurements were performed to reach the best cone beam computed tomography imaging quality possible. Once defined, a clinical feasibility study was initiated. An in-room cone beam computed tomography device is used to acquire intraoperative images after placing the applicator. Repositioning the applicator is thereafter discussed with the surgeon, according to the imaging outcomes, if required. Results: An optimal image quality was achieved with 120-kV voltage, 20-mA current, and a tube current time product of 150 mAs. An additional 0.51 mSv patient exposure was calculated for the entire procedure. The wide dynamic range (-600 HU to +600 HU) of cone beam computed tomography and a 27 HU mean computed tomography values difference between brain tissue and spherical applicator allows distinguishing both structures. In this first in-human experience, the applicator was repositioned after evidencing air gaps, assuring full applicator-to-surface contact. Conclusions: This first in-human procedure confirmed the feasibility of kilovoltage image guided intraoperative radiation therapy in a neurosurgical setting. A prospective study has been initiated and will provide further dosimetric details.

Functional outcome after late cranioplasty after decompressive craniectomy: a single-center retrospective study.

OBJECTIVE: The best time for cranioplasty (CP) after decompressive craniectomy (DC) is controversial, and there are no authoritative guidelines yet. Both complications as well as outcome may depend on the timing of CP. The aim of this single-center study was to evaluate the impact of late CP on procedural safety as well as on patient outcome. METHODS: All patients receiving CP at a tertiary university medical center between 01/2015 and 12/2022 were included retrospectively. Patients' conditions were assessed according to the modified Rankin Scale (mRS) prior to CP and 6 months after. Baseline characteristics, indication for DC, time from DC to CP, and postoperative complications according to the Landriel Ibañez Classification were analyzed. RESULTS: CP was performed in 271 patients who previously underwent DC due to traumatic brain injury (25.5%), ischemic stroke (29.5%), aneurysmal subarachnoid hemorrhage (26.9%), or intracerebral hemorrhage (18.1%). The median interval between DC and CP was 143 days (interquartile range 112-184 days). Receiver operating characteristic analysis revealed a cut-off of 149 days, where CP performed within 149 days after DC led to an improvement on mRS after CP (p = 0.001). In multivariate analysis, additional rehabilitation after and better mRS before CP were independently associated with improvement of outcome. The rate of complications was similar between early and late CP (24.8% and 25.4%, respectively, p = 0.562). CONCLUSIONS: Late cranioplasty is a safe procedure. The outcome was improved when additional rehabilitation was performed after cranioplasty and was not associated with the timing of cranioplasty.

Defining benchmark outcomes for mesial temporal lobe epilepsy surgery: A global multicenter analysis of 1119 cases.

OBJECTIVE: Benchmarking has been proposed to reflect surgical quality and represents the highest standard reference values for desirable results. We sought to determine benchmark outcomes in patients after surgery for drug-resistant mesial temporal lobe epilepsy (MTLE). METHODS: This retrospective multicenter study included patients who underwent MTLE surgery at 19 expert centers on five continents. Benchmarks were defined for 15 endpoints covering surgery and epilepsy outcome at discharge, 1 year after surgery, and the last available follow-up. Patients were risk-stratified by applying outcome-relevant comorbidities, and benchmarks were calculated for low-risk ("benchmark") cases. Respective measures were derived from the median value at each center, and the 75th percentile was considered the benchmark cutoff. RESULTS: A total of 1119 patients with a mean age (range) of 36.7 (1-74) years and a male-to-female ratio of 1:1.1 were included. Most patients (59.2%) underwent anterior temporal lobe resection with amygdalohippocampectomy. The overall rate of complications or neurological deficits was 14.4%, with no in-hospital death. After risk stratification, 377 (33.7%) benchmark cases of 1119 patients were identified, representing 13.6%-72.9% of cases per center and leaving 742 patients in the high-risk cohort. Benchmark cutoffs for any complication, clinically apparent stroke, and reoperation rate at discharge were ≤24.6%, ≤.5%, and ≤3.9%, respectively. A favorable seizure outcome (defined as International League Against Epilepsy class I and II) was reached in 83.6% at 1 year and 79.0% at the last follow-up in benchmark cases, leading to benchmark cutoffs of ≥75.2% (1-year follow-up) and ≥69.5% (mean follow-up of 39.0 months). SIGNIFICANCE: This study presents internationally applicable benchmark outcomes for the efficacy and safety of MTLE surgery. It may allow for comparison between centers, patient registries, and novel surgical and interventional techniques.

Multicentric Assessment of Safety and Efficacy of Combinatorial Adjuvant Brain Metastasis Treatment by Intraoperative Radiation Therapy and Immunotherapy.

PURPOSE: After surgical resection of brain metastases (BMs), intraoperative radiation therapy (IORT) provides a promising alternative to adjuvant external beam radiation therapy by enabling superior organ-at-risk preservation, reduction of in-hospital times, and timely admission to subsequent systemic treatments, which increasingly comprise novel targeted immunotherapeutic approaches. We sought to assess the safety and efficacy of IORT in combination with immune checkpoint inhibitors (ICIs) and other targeted therapies (TTs). METHODS AND MATERIALS: In a multicentric approach incorporating individual patient data from 6 international IORT centers, all patients with BMs undergoing IORT were retrospectively assessed for combinatorial treatment with ICIs/TTs and evaluated for toxicity and cumulative rates, including wound dehiscence, radiation necrosis, leptomeningeal spread, local control, distant brain progression (DBP), and estimated overall survival. RESULTS: In total, 103 lesions with a median diameter of 34 mm receiving IORT combined with immunomodulatory systemic treatment or other TTs were included. The median follow-up was 13.2 (range, 1.2-102.4) months, and the median IORT dose was 25 (range, 18-30) Gy prescribed to the applicator surface. There was 1 grade 3 adverse event related to IORT recorded (2.2%). A 4.9% cumulative radiation necrosis rate was observed. The 1-year local control rate was 98.0%, and the 1-year DBP-free survival rate was 60.0%. Median time to DBP was 5.5 (range, 1.0-18.5) months in the subgroup of patients experiencing DBP, and the cumulative leptomeningeal spread rate was 4.9%. The median estimated overall survival was 26 (range, 1.2 to not reached) months with a 1-year survival rate of 74.0%. Early initiation of immunotherapy/TTs was associated with a nonsignificant trend toward improved DBP rate and overall survival. CONCLUSIONS: The combination of ICIs/TTs with IORT for resected BMs does not seem to increase toxicity and yields encouraging local control outcomes in the difficult-to-treat subgroup of larger BMs. Time gaps between surgery and systemic treatment could be shortened or avoided. The definitive role of IORT in local control after BM resection will be defined in a prospective trial.

Frequency and Characteristics of Spinal Bleeding Sources in Nontraumatic Angiogram-Negative Subarachnoid Hemorrhage.

INTRODUCTION: Angiogram-negative subarachnoid hemorrhage (AN-SAH) accounts for 5-15% of spontaneous SAH. This study aims to analyze the frequency and characteristics of spinal bleeding sources in patients with AN-SAH. METHODS: 140 patients suffering from AN-SAH treated at our institution from 2012 to 2022 were included in this retrospective cohort study. RESULTS: 52.1% were diagnosed with perimesencephalic SAH, 35.0% with non-perimesencephalic, SAH and 12.9% with CT-negative SAH (diagnosed by lumbar puncture). Additional magnetic resonance imaging (MRI) identified a spinal bleeding source in 4 patients (2.86%). These patients presented with local spine pain or neurological deficits (relative risk: 3.9706 [95% confidence interval [CI]: 0.7272-21.6792]; p < 0.001) and were younger (mean difference 14.85 years [95% CI: 0.85-28.85; p = 0.038]) compared to patients without a spinal bleeding source. CONCLUSIONS: AN-SAH caused by spinal pathology is rare. This study indicates that craniocervical and holospinal MRI should be considered in AN-SAH, especially for young patients with AN-SAH who present with back pain or neurological deficits.

The proneural subtype is not associated with survival benefit from bevacizumab in newly diagnosed glioblastoma: a secondary analysis of the GLARIUS trial.

PURPOSE: The AVAglio trial reported a significant survival benefit for first line bevacizumab treatment in patients with IDH wildtype glioblastoma of the proneural gene expression subtype. We here aim to replicate these findings in an independent trial cohort. METHODS: We evaluate the treatment benefit of bevacizumab according to gene expression subtypes of pretreatment tumor samples (n = 123) in the GLARIUS trial (NCT00967330) for MGMT unmethylated glioblastoma patients with Kaplan-Meier analyses, log-rank tests and Cox regression models. RESULTS: Employing the Phillips classifier, bevacizumab conferred a significant PFS advantage in patients with proneural IDH wild-type tumors (10.4 vs. 6.0 months, p = 0.002), but no OS advantage (16.4 vs. 17.4 months, p = 0.6). Multivariable analysis adjusting for prognostic covariates confirmed the absence of a significant OS advantage from bevacizumab (hazard ratio, 1.05, 95% CI, 0.42 to 2.64; p = 0.14). Further, there was no interaction between the proneural subtype and treatment arm (p = 0.15). These results were confirmed in analyses of tumor subgroups according to the Verhaak classifier. CONCLUSION: In contrast to AVAglio, glioblastoma gene expression subgroups were not associated with a differential OS benefit from first-line bevacizumab in the GLARIUS trial.

Intraoperative or postoperative stereotactic radiotherapy for brain metastases: time to systemic treatment onset and other patient-relevant outcomes.

PURPOSE: Intraoperative radiotherapy (IORT) has become a viable treatment option for resectable brain metastases (BMs). As data on local control and radiation necrosis rates are maturing, we focus on meaningful secondary endpoints such as time to next treatment (TTNT), duration of postoperative corticosteroid treatment, and in-hospital time. METHODS: Patients prospectively recruited within an IORT study registry between November 2020 and June 2023 were compared with consecutive patients receiving adjuvant stereotactic radiotherapy (SRT) of the resection cavity within the same time frame. TTNT was defined as the number of days between BM resection and start of the next extracranial oncological therapy (systemic treatment, surgery, or radiotherapy) for each of the groups. RESULTS: Of 95 BM patients screened, IORT was feasible in 84 cases (88%) and ultimately performed in 64 (67%). The control collective consisted of 53 SRT patients. There were no relevant differences in clinical baseline features. Mean TTNT (range) was 36 (9 - 94) days for IORT patients versus 52 (11 - 126) days for SRT patients (p = 0.01). Mean duration of postoperative corticosteroid treatment was similar (8 days; p = 0.83), as was mean postoperative in-hospital time (11 versus 12 days; p = 0.97). Mean total in-hospital time for BM treatment (in- and out-patient days) was 11 days for IORT versus 19 days for SRT patients (p < 0.001). CONCLUSION: IORT for BMs results in faster completion of interdisciplinary treatment when compared to adjuvant SRT, without increasing corticosteroid intake or prolonging in-hospital times. A randomised phase III trial will determine the clinical effects of shorter TTNT.

Delayed Internal Carotid Artery Dissection Mimicking Cerebral Vasospasms after Subarachnoid Hemorrhage: A Case Report.

BACKGROUND: Delayed cerebral ischemia (DCI) is usually caused by cerebral vasospasm (CVS). To detect DCI and CVS a cranial CT scan will be performed, but cervical vessels are not necessarily displayed. PATIENT: A 63-year-old female patient who suffered from aneurysmal subarachnoid hemorrhage (SAH) was treated at the authors' institution. After an initially unremarkable clinical course, she developed aphasia on day 11. CT angiography (CTA) and perfusion imaging revealed significant hypoperfusion of the left hemisphere. In addition, the CTA showed a subtotal stenosis of the internal carotid artery (ICA) at the level of the petrous segment, suspicious for a dissection. This was not detectable angiographically in the final control of the intervention and was also not clinically evident until day 11. Cerebral perfusion as well as the clinical symptoms normalized rapidly after stent reconstruction of the ICA. CONCLUSION: Even though CVS is the most frequent cause of hypoperfusion in patients after SAH, a periinterventional dissection can also lead to relevant stenosis and thus to a disturbed cerebral perfusion and corresponding neurological deficits. The time delay between the intervention and the clinical as well as CT-angiographical manifestation in our case is remarkable.

Long-term neurocognitive function and quality of life after multimodal therapy in adult glioma patients: a prospective long-term follow-up.

PURPOSE: Multimodal therapies have significantly improved prognosis in glioma. However, in particular radiotherapy may induce long-term neurotoxicity compromising patients' neurocognition and quality of life. The present prospective multicenter study aimed to evaluate associations of multimodal treatment with neurocognition with a particular focus on hippocampal irradiation. METHODS: Seventy-one glioma patients (WHO grade 1-4) were serially evaluated with neurocognitive testing and quality of life questionnaires. Prior to (baseline) and following further treatment (median 7.1 years [range 4.6-11.0] after baseline) a standardized computerized neurocognitive test battery (NeuroCog FX) was applied to gauge psychomotor speed and inhibition, verbal short-term memory, working memory, verbal and non-verbal memory as well as verbal fluency. Mean ipsilateral hippocampal radiation dose was determined in a subgroup of 27 patients who received radiotherapy according to radiotherapy plans to evaluate its association with neurocognition. RESULTS: Between baseline and follow-up mean performance in none of the cognitive domains significantly declined in any treatment modality (radiotherapy, chemotherapy, combined radio-chemotherapy, watchful-waiting), except for selective attention in patients receiving chemotherapy alone. Apart from one subtest (inhibition), mean ipsilateral hippocampal radiation dose > 50 Gy (Dmean) as compared to < 10 Gy showed no associations with long-term cognitive functioning. However, patients with Dmean < 10 Gy showed stable or improved performance in all cognitive domains, while patients with > 50 Gy numerically deteriorated in 4/8 domains. CONCLUSIONS: Multimodal glioma therapy seems to affect neurocognition less than generally assumed. Even patients with unilateral hippocampal irradiation with > 50 Gy showed no profound cognitive decline in this series.

Opportunities and Alternatives of Modern Radiation Oncology and Surgery for the Management of Resectable Brain Metastases.

Postsurgical radiotherapy (RT) has been early proven to prevent local tumor recurrence, initially performed with whole brain RT (WBRT). Subsequent to disadvantageous cognitive sequalae for the patient and the broad distribution of modern linear accelerators, focal irradiation of the tumor has omitted WBRT in most cases. In many studies, the effectiveness of local RT of the resection cavity, either as single-fraction stereotactic radiosurgery (SRS) or hypo-fractionated stereotactic RT (hFSRT), has been demonstrated to be effective and safe. However, whereas prospective high-level incidence is still lacking on which dose and fractionation scheme is the best choice for the patient, further ablative techniques have come into play. Neoadjuvant SRS (N-SRS) prior to resection combines straightforward target delineation with an accelerated post-surgical phase, allowing an earlier start of systemic treatment or rehabilitation as indicated. In addition, low-energy intraoperative RT (IORT) on the surgical bed has been introduced as another alternative to external beam RT, offering sterilization of the cavity surface with steep dose gradients towards the healthy brain. This consensus paper summarizes current local treatment strategies for resectable brain metastases regarding available data and patient-centered decision-making.

Outcome assessment of intraoperative radiotherapy for brain metastases: results of a prospective observational study with comparative matched-pair analysis.

PURPOSE: Intraoperative radiation therapy (IORT) is an emerging alternative to adjuvant stereotactic external beam radiation therapy (EBRT) following resection of brain metastases (BM). Advantages of IORT include an instant prevention of tumor regrowth, optimized dose-sparing of adjacent healthy brain tissue and immediate completion of BM treatment, allowing an earlier admission to subsequent systemic treatments. However, prospective outcome data are limited. We sought to assess long-term outcome of IORT in comparison to EBRT. METHODS: A total of 35 consecutive patients, prospectively recruited within a study registry, who received IORT following BM resection at a single neuro-oncological center were evaluated for radiation necrosis (RN) incidence rates, local control rates (LCR), distant brain progression (DBP) and overall survival (OS) as long-term outcome parameters. The 1 year-estimated OS and survival rates were compared in a balanced comparative matched-pair analysis to those of our institutional database, encompassing 388 consecutive patients who underwent adjuvant EBRT after BM resection. RESULTS: The median IORT dose was 30 Gy prescribed to the applicator surface. A 2.9% RN rate was observed. The estimated 1 year-LCR was 97.1% and the 1 year-DBP-free survival 73.5%. Median time to DBP was 6.4 (range 1.7-24) months in the subgroup of patients experiencing intracerebral progression. The median OS was 17.5 (0.5-not reached) months with a 1 year-survival rate of 61.3%, which did not not significantly differ from the comparative cohort (p = 0.55 and p = 0.82, respectively). CONCLUSION: IORT is a safe and effective fast-track approach following BM resection, with comparable long-term outcomes as adjuvant EBRT.

An open presurgery MRI dataset of people with epilepsy and focal cortical dysplasia type II.

Automated detection of lesions using artificial intelligence creates new standards in medical imaging. For people with epilepsy, automated detection of focal cortical dysplasias (FCDs) is widely used because subtle FCDs often escape conventional neuroradiological diagnosis. Accurate recognition of FCDs, however, is of outstanding importance for affected people, as surgical resection of the dysplastic cortex is associated with a high chance of postsurgical seizure freedom. Here, we make publicly available a dataset of 85 people affected by epilepsy due to FCD type II and 85 healthy control persons. We publish 3D-T1 and 3D-FLAIR, manually labeled regions of interest, and carefully selected clinical features. The open presurgery MRI dataset may be used to validate existing automated algorithms of FCD detection as well as to create new approaches. Most importantly, it will enable comparability of already existing approaches and support a more widespread use of automated lesion detection tools.

Incurring detriments of unplanned readmission to the intensive care unit following surgery for brain metastasis.

OBJECT: Postoperative intensive care unit (ICU) monitoring is a common regime after neurosurgical resection of brain metastasis (BM). In comparison, unplanned secondary readmission to the ICU after initial postoperative treatment course occurs in response to adverse events and might significantly impact patient prognosis. In the present study, we analyzed the potential prognostic implications of unplanned readmission to the ICU and aimed at identifying preoperatively collectable risk factors for the development of such adverse events. METHODS: Between 2013 and 2018, 353 patients with BM had undergone BM resection at the authors' institution. Secondary ICU admission was defined as any unplanned admission to the ICU during the initial hospital stay. A multivariable logistic regression analysis was performed to identify preoperatively identifiable risk factors for unplanned ICU readmission. RESULTS: A total of 19 patients (5%) were readmitted to the ICU. Median overall survival (mOS) of patients with unplanned ICU readmission was 2 months (mo) compared to 13 mo for patients without secondary ICU admission (p<0.0001). Multivariable analysis identified "multiple BM" (p=0.02) and "preoperative CRP levels > 10 mg/dl" (p=0.01) as significant and independent predictors of secondary ICU admission. CONCLUSIONS: Unplanned ICU readmission following surgical therapy for BM is significantly related to poor OS. Furthermore, the present study identifies routinely collectable risk factors indicating patients that are at a high risk for unplanned ICU readmission after BM surgery.

A novel geometry-based analysis of hippocampal morphometry in mesial temporal lobe epilepsy.

Hippocampal volumetry is an essential tool in researching and diagnosing mesial temporal lobe epilepsy (mTLE). However, it has a limited ability to detect subtle alterations in hippocampal morphometry. Here, we establish and apply a novel geometry-based tool that enables point-wise morphometric analysis based on an intrinsic coordinate system of the hippocampus. We hypothesized that this point-wise analysis uncovers structural alterations not measurable by volumetry, but associated with histological underpinnings and the neuropsychological profile of mTLE. We conducted a retrospective study in 204 individuals with mTLE and 57 age- and gender-matched healthy subjects. FreeSurfer-based segmentations of hippocampal subfields in 3T-MRI were subjected to a geometry-based analysis that resulted in a coordinate system of the hippocampal mid-surface and allowed for point-wise measurements of hippocampal thickness and other features. Using point-wise analysis, we found significantly lower thickness and higher FLAIR signal intensity in the entire affected hippocampus of individuals with hippocampal sclerosis (HS-mTLE). In the contralateral hippocampus of HS-mTLE and the affected hippocampus of MRI-negative mTLE, we observed significantly lower thickness in the presubiculum. Impaired verbal memory was associated with lower thickness in the left presubiculum. In HS-mTLE histological subtype 3, we observed higher curvature than in subtypes 1 and 2 (all p < .05). These findings could not be observed using conventional volumetry (Bonferroni-corrected p < .05). We show that point-wise measures of hippocampal morphometry can uncover structural alterations not measurable by volumetry while also reflecting histological underpinnings and verbal memory. This substantiates the prospect of their clinical application.

Additive prognostic impact of the cerebrospinal fluid arginine/ornithine ratio to established clinical scores in aneurysmal subarachnoid hemorrhage.

Cerebrospinal fluid (CSF) metabolites are increasingly recognized as prognostic factors in aneurysmal subarachnoid hemorrhage (SAH). The CSF arginine/ornithine ratio (Arg/Orn) was shown to predict cerebral vasospasms and clinical outcome in SAH. The additive prognostic value of Arg/Orn over established prognostic scores has not been investigated. CSF Arg/Orn and the established prognostic scores SAH, FRESH, SAH-PDS, HAIR, Rosen-McDonald, Hunt and Hess, WFNS and modified Fisher scale were determined in a prospective cohort of patients with aneurysmal SAH. Logistic regression models to predict a favorable outcome, defined as a modified Rankin Scale score of 0-3 at 3 months follow-up, were constructed for each score, both with and without the addition of Arg/Orn. The impact of Arg/Orn was assessed comparing logistic regression models containing the respective score with and without Arg/Orn with the likelihood ratio chi-squared test. CSF Arg/Orn and clinical scores were determined in 38 SAH patients. Arg/Orn was an independent predictor of clinical outcome when added to established prognostic scores (p < 0.05) with the exception of HAIR (p = 0.078). All models were significantly improved if Arg/Orn was added as a covariable (p < 0.05). The results of this study confirm Arg/Orn as an independent prognostic factor and its addition improves established prognostic models in SAH.

Postoperative prolonged mechanical ventilation in patients with surgically treated pyogenic spondylodiscitis: a surrogate endpoint for early postoperative mortality.

Surgical procedures with spinal instrumentation constitute a prevalent and occasionally highly indicated treatment modality in patients with pyogenic spondylodiscitis (PSD). However, surgical therapy might be associated with the need of prolonged postoperative intensive care medicine which in turn might impair intended operative benefit. Therefore, we analyzed prolonged mechanical ventilation (PMV) as an indicator variable for such intensive care treatment with regard to potential correlations with mortality in this vulnerable patient cohort. Between 2012 and 2018, 177 consecutive patients received stabilization surgery for PSD at the authors' neurosurgical department. PMV was defined as postoperative mechanical ventilation of more than 24 h. A multivariable analysis was performed to identify independent predictors for 30-day mortality. Twenty-three out of 177 patients (13%) with PSD suffered from postoperative PMV. Thirty-day mortality rate was 5%. Multivariable analysis identified "spinal empyema" (p = 0.02, odds ratio (OR) 6.2, 95% confidence interval (CI) 1.3-30.2), "Charlson comorbidity index (CCI) > 2" (p = 0.04, OR 4.0, 95% CI 1.0-15.5), "early postoperative complications (PSIs)" (p = 0.001, OR 17.1, 95% CI 3.1-96.0) and "PMV > 24 hrs" (p = 0.002, OR 13.0, 95% CI 2.7-63.8) as significant and independent predictors for early postoperative mortality. The present study indicates PMV to significantly correlate to elevated early postoperative mortality rates following stabilization surgery for PSD. These results might entail further scientific efforts to investigate PMV as a so far underestimated negative prognostic factor in the surgical treatment of PSD.

Correlation between Blood Type 0 and Risk of Chronic Subdural Hematoma Recurrence: A Single Center Retrospective Cohort Study.

Chronic subdural hematoma (cSDH) is a common disease in the neurological and neurosurgical world. The recommended treatment for cSDH patients with moderate or severe neurological symptoms is surgical evacuation, but cSDH frequently recurs. The patient's ABO blood type may influence the outcome. This study aims to evaluate the correlation between cSDH recurrence and blood type O. We performed a retrospective analysis of the data of patients with cSDH who were surgically treated. Recurrence was defined as the need for re-operation within the first 12 weeks after the initial surgery. We analyzed standard demographic data, duration and type of surgery, ABO blood types, and the re-operation rate. Univariate and multivariate analyses were conducted. A total of 229 patients were included. The recurrence of hematoma was identified in 20.5% of patients. Blood type O was found to be significantly associated with cSDH recurrence leading to re-operation within 12 weeks (p = 0.02, OR 1.9, 95% CI 1.1-3.5). Thrombocyte aggregation inhibition and oral anticoagulants were not predictors of cSDH recurrence. Patients with blood type O in our cohort were identified to be at higher risk of cSDH recurrence and may, therefore, be a more vulnerable patient group. This finding needs further evaluation in larger cohorts.