Differentiation of multiple brain metastases and glioblastoma with multiple foci using MRI criteria.

OBJECTIVE: Glioblastoma with multiple foci (mGBM) and multiple brain metastases share several common features on magnetic resonance imaging (MRI). A reliable preoperative diagnosis would be of clinical relevance. The aim of this study was to explore the differences and similarities between mGBM and multiple brain metastases on MRI. METHODS: We performed a retrospective analysis of 50 patients with mGBM and compared them with a cohort of 50 patients with multiple brain metastases (2-10 lesions) histologically confirmed and treated at our department between 2015 and 2020. The following imaging characteristics were analyzed: lesion location, distribution, morphology, (T2-/FLAIR-weighted) connections between the lesions, patterns of contrast agent uptake, apparent diffusion coefficient (ADC)-values within the lesion, the surrounding T2-hyperintensity, and edema distribution. RESULTS: A total of 210 brain metastases and 181 mGBM lesions were analyzed. An infratentorial localization was found significantly more often in patients with multiple brain metastases compared to mGBM patients (28 vs. 1.5%, p < 0.001). A T2-connection between the lesions was detected in 63% of mGBM lesions compared to 1% of brain metastases. Cortical edema was only present in mGBM. Perifocal edema with larger areas of diffusion restriction was detected in 31% of mGBM patients, but not in patients with metastases. CONCLUSION: We identified a set of imaging features which improve preoperative diagnosis. The presence of T2-weighted imaging hyperintensity connection between the lesions and cortical edema with varying ADC-values was typical for mGBM.

Liquid Biopsy in Low-Grade Glioma: A Systematic Review and a Proposal for a Clinical Utility Score.

Liquid biopsy research on Low-Grade gliomas (LGG) has remained less conspicuous than that on other malignant brain tumors. Reliable serum markers would be precious for diagnosis, follow- up and treatment. We propose a clinical utility score (CUS) for biomarkers in LGG that mirrors their clinical usefulness. We conducted a PRISMA review. We examined each biomarker classifying them by CUS and Level of Evidence (LOE). We identified four classes of biomarkers: (1). Circulating protein-(a) vitronectin discriminates LGG from HGG (Sn:98%, Sp:91%, CUS: 3, LOE: III), (b) CTLA-4 discriminates LGG from HGG, (cutoff: 220.43 pg/ml, Sn: 82%, Sp: 78%, CUS:3, LOE:III), (c) pre-operative TGF b1 predict astrocytoma (cutoff: 2.52 ng/ml, Sn: 94.9%, Sp: 100%, CUS:3, LOE:VI). (2). micro-RNA (miR)-(a) miR-16 discriminates between WHO IV and WHO II and III groups (AUC = 0.98, CUS:3, LOE: III), (b) miR-454-3p is higher in HGG than in LGG (p = 0.013, CUS:3, LOE: III), (c) miR-210 expression is related to WHO grades (Sn 83.2%, Sp 94.3%, CUS: 3, LOE: III). (3). Circulating DNA-(a) IDH1R132H mutation detected in plasma by combined COLD and digital PCR (Sn: 60%, Sp: 100%, CUS: 3, LOE: III). 4. Exosomes-(a) SDC1 serum levels could discriminate GBM from LGG (Sn: 71%, Sp: 91%, CUS: 2C, LOE: VI). Our investigation showed that miRs appear to have the highest clinical utility. The LOE of the studies assessed is generally low. A combined approach between different biomarkers and traditional diagnostics may be considered. We identified four main classes of biomarkers produced by LGG. We examined each biomarker, classifying them by clinical utility score (CUS) and level of evidence (LOE). Micro-RNA (miRs) appears to have the highest CUS and LOE.

Robot-assisted spinal augmentation procedures: is it worth the increased effort?

PURPOSE: Spinal augmentation procedures (SAP) are standard procedures for vertebral compression fractures. Often, SAPs are carried out in a minimally invasive, percutaneous way. Certain anatomic conditions such as small pedicles or kyphotic deformities resulting from a significant collapse of the vertebral body might render the operation more difficult and increase the risk of complications. Thus, robot assistance might be useful to optimize the trajectory and to reduce procedure-associated complications. In this study robot-assisted percutaneous SAPs are compared with conventional fluoroscopy-guided percutaneous SAP. METHODS: A retrospective observational analysis was carried out. Standard demographic parameters were analyzed. Procedural data including radiation dosage records were screened. Biomechanical data were recorded. Cement volumes were analyzed. The precision of the pedicular trajectory was reviewed, and misplaced trajectories were categorized. Procedure-associated complications were analyzed and evaluated for their clinical significance. RESULTS: A total of 130 procedures were reviewed, and 94 patients were finally included. Osteoporotic fractures (OF) were the main indication (60.7%; OF 2-44%, OF 4-33%). Demographic parameters and clinically relevant complications were equally distributed between the two groups. Duration of surgery was significantly longer in robot-assisted procedures (p < 0.001). Intraoperative radiation exposure was equally distributed. Injected cement volume was similar in both groups. There was no significant difference in pedicle trajectory deviation. CONCLUSION: The use of robot assistance in SAP seems not to be superior with regard to accuracy, radiation exposure and the rate of complications when compared to fluoroscopy-guided SAP.

Surgery for brain metastases: radiooncology scores predict survival-score index for radiosurgery, graded prognostic assessment, recursive partitioning analysis.

BACKGROUND: Radiooncological scores are used to stratify patients for radiation therapy. We assessed their ability to predict overall survival (OS) in patients undergoing surgery for metastatic brain disease. METHODS: We performed a post-hoc single-center analysis of 175 patients, prospectively enrolled in the MetastaSys study data. Score index of radiosurgery (SIR), graded prognostic assessment (GPA), and recursive partitioning analysis (RPA) were assessed. All scores consider age, systemic disease, and performance status prior to surgery. Furthermore, GPA and SIR include the number of intracranial lesions while SIR additionally requires metastatic lesion volume. Predictive values for case fatality at 1 year after surgery were compared among scoring systems. RESULTS: All scores produced accurate reflections on OS after surgery (p ≤ 0.003). Median survival was 21-24 weeks in patients scored in the unfavorable cohorts, respectively. In cohorts with favorable scores, median survival ranged from 42 to 60 weeks. Favorable SIR was associated with a hazard ratio (HR) of 0.44 [0.29, 0.66] for death within 1 year. For GPA, the HR amounted to 0.44 [0.25, 0.75], while RPA had a HR of 0.30 [0.14, 0.63]. Overall test performance was highest for the SIR. CONCLUSIONS: All scores proved useful in predicting OS. Considering our data, we recommend using the SIR for preoperative prognostic evaluation and counseling.

Endoscope-enhanced fluorescence-guided microsurgery increases survival in patients with glioblastoma.

PURPOSE: Extent of resection (EOR) predicts progression-free survival (PFS) and may impact overall survival (OS) in patients with glioblastoma. We recently demonstrated that 5-aminolevulinic acid-(5-ALA)-fluorescence-enhanced endoscopic surgery increase the rate of gross total resection. However, it is hitherto unknown whether fluorescence-enhanced endoscopic resection affects survival. METHODS: We conducted a retrospective single-center analysis of a consecutive series of patients who underwent surgery for non-eloquently located glioblastoma between 2011 and 2018. All patients underwent fluorescence-guided microscopic or fluorescence-guided combined microscopic and endoscopic resection. PFS, OS, EOR as well as clinical and demographic parameters, adjuvant treatment modalities, and molecular characteristics were compared between microscopy-only vs. endoscopy-assisted microsurgical resection. RESULTS: Out of 114 patients, 73 (65%) were male, and 57 (50%) were older than 65 years. Twenty patients (18%) were operated on using additional endoscopic assistance. Both cohorts were equally distributed in terms of age, performance status, lesion location, adjuvant treatment modalities, and molecular status. Gross total resection was achieved in all endoscopy-assisted patients compared to about three-quarters of microscope-only patients (100% vs. 75.9%, p=0.003). The PFS in the endoscope-assisted cohort was 19.3 months (CI95% 10.8-27.7) vs. 10.8 months (CI95% 8.2-13.4; p=0.012) in the microscope-only cohort. OS in the endoscope-assisted group was 28.9 months (CI95% 20.4-34.1) compared to 16.8 months (CI95% 14.0-20.9), in the microscope-only group (p=0.001). CONCLUSION: Endoscope-assisted fluorescence-guided resection of glioblastoma appears to substantially enhance gross total resection and OS. The strong effect size observed herein is contrasted by the limitations in study design. Therefore, prospective validation is required before we can generalize our findings.

Incidence and Outcome of Aneurysmal Subarachnoid Hemorrhage: The Swiss Study on Subarachnoid Hemorrhage (Swiss SOS).

BACKGROUND AND PURPOSE: The purpose of this study was to assess nationwide incidence and outcomes of aneurysmal subarachnoid hemorrhage (aSAH). The Swiss SOS (Swiss Study on Subarachnoid Hemorrhage) was established in 2008 and offers the unique opportunity to provide this data from the point of care on a nationwide level. METHODS: All patients with confirmed aneurysmal subarachnoid hemorrhage admitted between January 1, 2009 and December 31, 2014, within Switzerland were recorded in a prospective registry. Incidence rates were calculated based on time-matched population data. Admission parameters and outcomes at discharge and at 1 year were recorded. RESULTS: We recorded data of 1787 consecutive patients. The incidence of aneurysmal subarachnoid hemorrhage in Switzerland was 3.7 per 100 000 persons/y. The number of female patients was 1170 (65.5%). With a follow-up rate of 91.3% at 1 year, 1042 patients (58.8%) led an independent life according to the modified Rankin Scale (0-2). About 1 in 10 patients survived in a dependent state (modified Rankin Scale, 3-5; n=185; 10.4%). Case fatality was 20.1% (n=356) at discharge and 22.1% (n=391) after 1 year. CONCLUSIONS: The current incidence of aneurysmal subarachnoid hemorrhage in Switzerland is lower than expected and an indication of a global trend toward decreasing admissions for ruptured intracranial aneurysms. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03245866.

Safety aspects of opioid-naïve patients with high-grade glioma treated with D,L-Methadone: an observational case series.

It was suggested that D, L-Methadone might improve the clinical course of glioma patients. Owing to massive press coverage, patients demand the prescription of D, L-Methadone, but regarding its adjunctive use in glioma therapy there is no standard medication plan. Furthermore, it is not known which side effects the administration of D, L-Methadone might harbor, especially if the patients are opioid-naïve and if D, L-Methadone therapy was managed by the patients themselves or their general practitioners. Opioid-naïve patients with high-grade glioma (new diagnosis or recurrent) receiving D, L-Methadone were included in this retrospective observational analysis. Side effects were assigned if the condition deteriorated in conjunction with the initiation of D, L-Methadone and resolved/ ameliorated after cessation of the intake/reduction of the dosage. Side effects were categorized according to the common toxicity criteria (CTC). Twenty-four patients were included. All patients were opioid-naïve and received D, L-Methadone from their general practitioners. Sixteen patients experienced side effects. The median dosage when side effects began to occur was 15.8 mg/ 24 h. Fatigue and mood changes were reported most frequently (14 of 24 patients). Five patients had severe side effects related to relatively high doses. In all cases, symptoms resolved after cessation or dose reduction. Our results show that D/L M intake lead to frequent occurrence of side effects in opioid-naïve patients especially when not handled with caution and close supervision. Patients, their relatives, their GPs and neuro-oncologists need to be informed about the broad spectrum of side effects in order to thoroughly counsel glioma patients.

Do we underdiagnose osteoporosis in patients with pyogenic spondylodiscitis?

OBJECTIVE: Pyogenic spondylodiscitis affects a fragile patient population. Surgical treatment in cases of instability entails instrumentation, and loosening of this instrumentation is a frequent occurrence in pyogenic spondylodiscitis. The authors therefore attempted to investigate whether low bone mineral density (BMD)-which is compatible with the diagnosis of osteoporosis-is underdiagnosed in patients with pyogenic spondylodiscitis. How osteoporosis was treated and how it affected implant stability were further analyzed. METHODS: Charts of patients who underwent operations for pyogenic spondylodiscitis were retrospectively reviewed for clinical data, prior medical history of osteoporosis, and preoperative CT scans of the thoracolumbar spine. In accordance with a previously validated high-fidelity opportunistic CT assessment, average Hounsfield units (HUs) in vertebral bodies of L1 and L4 were measured. Based on the validation study, the authors opted for a conservative cutoff value for low BMD, being compatible with osteoporosis ≤ 110 HUs. Baseline and outcome variables, including implant failure and osteoporosis interventions, were entered into a multivariate logistic model for statistical analysis. RESULTS: Of 200 consecutive patients who underwent fusion surgery for pyogenic spondylodiscitis, 64% (n = 127) were male and 66% (n = 132) were older than 65 years. Seven percent (n = 14) had previously been diagnosed with osteoporosis. The attenuation analysis revealed HU values compatible with osteoporosis in 48% (95/200). The need for subsequent revision surgery due to implant failure showed a trend toward an association with estimated low BMD (OR 2.11, 95% CI 0.95-4.68, p = 0.067). Estimated low BMD was associated with subsequent implant loosening (p < 0.001). Only 5% of the patients with estimated low BMD received a diagnosis and pharmacological treatment of osteoporosis within 1 year after spinal instrumentation. CONCLUSIONS: Relying on past medical history of osteoporosis is insufficient in the management of patients with pyogenic spondylodiscitis. This is the first study to identify a substantially missed opportunity to detect osteoporosis and to start pharmacological treatment after surgery for prevention of implant failure. The authors advocate for routine opportunistic CT evaluation for a better estimation of bone quality to initiate diagnosis and treatment for osteoporosis in these patients.

Association of single and multiple aneurysms with tobacco abuse: an @neurIST risk analysis.

OBJECTIVE: Although several studies have suggested that the incidence of intracranial aneurysms (IAs) is higher in smokers, the higher prevalence of subarachnoid hemorrhage (SAH) in smokers remains uncertain. It is unclear whether smoking additionally contributes to the formation of multiple aneurysms and the risk of rupture. The aim of this study was to determine whether smoking is associated with IA formation, multiplicity, or rupture. METHODS: Patients from the prospective multicenter @neurIST database (n = 1410; 985 females [69.9%]) were reviewed for the presence of SAH, multiple aneurysms, and smoking status. The prevalence of smokers in the population of patients diagnosed with at least one IA was compared with that of smokers in the general population. RESULTS: The proportion of smokers was higher in patients with IAs (56.2%) than in the reference population (51.4%; p < 0.001). A significant association of smoking with the presence of an IA was found throughout group comparisons (p = 0.01). The presence of multiple IAs was also significantly associated with smoking (p = 0.003). A trend was found between duration of smoking and the presence of multiple IAs (p = 0.057). However, the proportion of smokers among patients suffering SAH was similar to that of smokers among patients diagnosed with unruptured IAs (p = 0.48). CONCLUSIONS: Smoking is strongly associated with IA formation. Once an IA is present, however, smoking does not appear to increase the risk of rupture compared with IAs in the nonsmoking population. The trend toward an association between duration of smoking and the presence of multiple IAs stresses the need for counseling patients with IAs regarding lifestyle modification.

Cerebral metastases: do size, peritumoral edema, or multiplicity predict infiltration into brain parenchyma?

BACKGROUND: Brain metastases (BMs) are the most frequent malignancy of the central nervous system. Previous research suggested that some metastases show infiltrative behavior rather than sharp demarcation. We hypothesized that three magnetic resonance (MR) imaging parameters-(a) tumor size, (b) extent of peritumoral edema, and (c) presence of multiple BMs-are predictors of cellular invasion beyond the surgically identifiable tumor margins. METHODS: We performed a post hoc analysis on prospectively collected data of patients with BMs. Biopsies beyond the resection margin and immunohistochemistry were performed to assess infiltration status. The three MR imaging parameters were dichotomized into diameters ≤ 30 mm ("small") and > 30 mm ("large"), amount of peritumoral edema "extended" and "limited," and "multiple BMs" and "single BMs," respectively. The association between infiltration status and imaging parameters was calculated using chi-square test. RESULTS: Biopsy beyond the resection margin was performed in 77 patients; 49 (63.6%) had supramarginal infiltration and 28 patients (36.4%) showed no infiltration. Histological evidence of tumor infiltration was found in 25/41 patients with smaller lesions (61%) and in 24/36 with larger lesions (66.7%, p = 0.64), in 28/44 patients with limited (63.6%) and in 21/33 patients with extended edema (63.6%, p = 1.0), in 28/45 patients (62.2%) with single BM and in 21/32 patients (65.6%) with multiple BMs (p = 0.81). CONCLUSIONS: Based on the post hoc analysis of our prospective trial data, we could not confirm the hypothesis that infiltration of brain parenchyma beyond the glial pseudocapsule is associated with the MR imaging parameters tumor size, extent of edema, or multiplicity of metastases.

Correction to: Ruptured posterior circulation aneurysms: epidemiology, patterns of care, and outcomes from the Swiss SOS national registry.

The name of Roy Thomas Daniel was incorrectly captured in the original manuscript.

Ruptured posterior circulation aneurysms: epidemiology, patterns of care, and outcomes from the Swiss SOS national registry.

BACKGROUND: The treatment of ruptured posterior circulation aneurysms remains challenging despite progresses in the endovascular and neurosurgical techniques. OBJECTIVE: To provide epidemiological characterization of subjects presenting with ruptured posterior circulation aneurysms in Switzerland and thereby assessing the treatment patterns and neurological outcomes. METHODS: This is a retrospective analysis of the Swiss SOS registry for patients with aneurysmal subarachnoid hemorrhage. Patients were divided in 3 groups (upper, lower, and middle third) according to aneurysm location. Clinical, radiological, and treatment-related variables were identified and their impact on the neurological outcome was determined. RESULTS: From 2009 to 2014, we included 264 patients with ruptured posterior circulation aneurysms. Endovascular occlusion was the most common treatment in all 3 groups (72% in the upper third, 68% in the middle third, and 58.8% in the lower third). Surgical treatment was performed in 11.3%. Favorable outcome (mRS ≤ 3) was found in 56% at discharge and 65.7% at 1 year. No significant difference in the neurological outcome were found among the three groups, in terms of mRS at discharge (p = 0.20) and at 1 year (p = 0.18). High WFNS grade, high Fisher grade at presentation, and rebleeding before aneurysm occlusion (p = 0.001) were all correlated with the risk of unfavorable neurological outcome (or death) at discharge and at 1 year. CONCLUSIONS: In this study, endovascular occlusion was the principal treatment, with a favorable outcome for two-thirds of patients at discharge and at long term. These results are similar to high volume neurovascular centers worldwide, reflecting the importance of centralized care at specialized neurovascular centers.

Ruptured PICA aneurysms: presentation and treatment outcomes compared to other posterior circulation aneurysms. A Swiss SOS study.

BACKGROUND AND PURPOSE: Aneurysms of the posterior inferior cerebellar artery (PICA) are relatively uncommon and evidence is sparse about patients presenting with ruptured PICA aneurysms. We performed an analysis of the Swiss SOS national registry to describe clinical presentation, treatment pattern, and neurological outcome of patients with ruptured PICA aneurysms compared with other ruptured posterior circulation (PC) aneurysms. METHODS: This was a retrospective analysis of anonymized data from the Swiss SOS registry (Swiss Study on Aneurysmal Subarachnoid Hemorrhage; 2009-2014). Patients with ruptured PC aneurysms were subdivided into a PICA and non-PICA group. Clinical, radiological, and treatment-related variables were identified, and their impact on the neurological outcome was determined in terms of modified Rankin score at discharge and at 1 year of follow-up for the two groups. RESULTS: Data from 1864 aneurysmal subarachnoid hemorrhage patients were reviewed. There were 264 patients with a ruptured PC aneurysm. Seventy-four PICA aneurysms represented 28% of the series; clinical and radiological characteristics at admission were comparable between the PICA and non-PICA group. Surgical treatment was accomplished in 28% of patients in the PICA group and in the 4.8% of patients in the non-PICA group. No statistically significant difference was found between the two groups in terms of complications after treatment. Hydrocephalus requiring definitive shunt was needed in 21.6% of PICA patients (p = 0.6); cranial nerve deficit was present in average a quarter of the patients in both PICA and non-PICA group with no statistical difference (p = 0.3). A more favorable outcome (66.2%) was reported in the PICA group at discharge (p < 0.05) but this difference faded over time with a similar neurological outcome at 1-year follow-up (p = 0.09) between both PICA and non-PICA group. The Kaplan-Meyer estimation showed no significant difference in the mortality rate between both groups (p = 0.08). CONCLUSIONS: In the present study, patients with ruptured PICA aneurysms had a favorable neurological outcome in more than two thirds of cases, similar to patients with other ruptured PC aneurysms. Surgical treatment remains a valid option in a third of cases with ruptured PICA aneurysms.

Correction to: Ruptured PICA aneurysms: presentation and treatment outcomes compared to other posterior circulation aneurysms. A Swiss SOS study.

Incorrect authorgroup and authorname.

PI3K: A master regulator of brain metastasis-promoting macrophages/microglia.

Mutations and activation of the PI3K signaling pathway in breast cancer cells have been linked to brain metastases. However, here we describe that in some breast cancer brain metastases samples the protein expression of PI3K signaling components is restricted to the metastatic microenvironment. In contrast to the therapeutic effects of PI3K inhibition on the breast cancer cells, the reaction of the brain microenvironment is less understood. Therefore we aimed to quantify the PI3K pathway activity in breast cancer brain metastasis and investigate the effects of PI3K inhibition on the central nervous system (CNS) microenvironment. First, to systematically quantify the PI3K pathway activity in breast cancer brain metastases, we performed a prospective biomarker study using a reverse phase protein array (RPPA). The majority, namely 30 out of 48 (62.5%) brain metastatic tissues examined, revealed high PI3K signaling activity that was associated with a median overall survival (OS) of 9.41 months, while that of patients, whose brain metastases showed only moderate or low PI3K activity, amounted to only 1.93 and 6.71 months, respectively. Second, we identified PI3K as a master regulator of metastasis-promoting macrophages/microglia during CNS colonization; and treatment with buparlisib (BKM120), a pan-PI3K Class I inhibitor with a good blood-brain-barrier penetrance, reduced their metastasis-promoting features. In conclusion, PI3K signaling is active in the majority of breast cancer brain metastases. Since PI3K inhibition does not only affect the metastatic cells but also re-educates the metastasis-promoting macrophages/microglia, PI3K inhibition may hold considerable promise in the treatment of brain metastasis and the respective microenvironment.

Home-Time as a Surrogate Marker for Functional Outcome After Aneurysmal Subarachnoid Hemorrhage.

Background and Purpose­Commonly used tools to determine functional outcome after aneurysmal subarachnoid hemorrhage (aSAH) have limitations. Time spent at the patient's home has previously been proposed as a robust outcome measure after ischemic stroke. Here, we set out to validate home-time as an outcome measure after aSAH. Methods­We examined prospectively collected data from a nationwide multicenter registry of aSAH patients admitted to a tertiary neurosurgical department in Switzerland (Swiss SOS [Swiss Study on Aneurysmal Subarachnoid Hemorrhage]; 2009­2015). We calculated mean home-time (defined as days spent at home for the first 90 days after aSAH) and 95% CIs for each category of modified Rankin Scale at discharge and 1-year follow-up, using linear regression models to analyze home-time differences per modified Rankin Scale category. Results­We had home-time data from 1076 of 1866 patients (57.7%), and multiple imputation was used to fill-in missing data from the remaining 790 patients. Increasing home-time was associated with improved modified Rankin Scale scores at time of hospital discharge (P<0.0001) and at 1-year follow-up (P<0.0001). Within each of the 8 participating hospitals, the relationship between home-time and modified Rankin Scale was maintained. Conclusions­Home-time for the first 90 days after aSAH offers a robust and easily ascertainable outcome measure, discriminating particularly well across better recovery levels at time of hospital discharge and at 1-year follow-up. This measure complies with the modern trend of patient-centered healthcare and research, representing an outcome that is particularly relevant to the patient.

Predictors of In-Hospital Death After Aneurysmal Subarachnoid Hemorrhage: Analysis of a Nationwide Database (Swiss SOS [Swiss Study on Aneurysmal Subarachnoid Hemorrhage]).

BACKGROUND AND PURPOSE: To identify predictors of in-hospital mortality in patients with aneurysmal subarachnoid hemorrhage and to estimate their impact. METHODS: Retrospective analysis of prospective data from a nationwide multicenter registry on all aneurysmal subarachnoid hemorrhage cases admitted to a tertiary neurosurgical department in Switzerland (Swiss SOS [Swiss Study on Aneurysmal Subarachnoid Hemorrhage]; 2009-2015). Both clinical and radiological independent predictors of in-hospital mortality were identified, and their effect size was determined by calculating adjusted odds ratios (aORs) using multivariate logistic regression. Survival was displayed using Kaplan-Meier curves. RESULTS: Data of n=1866 aneurysmal subarachnoid hemorrhage patients in the Swiss SOS database were available. In-hospital mortality was 20% (n=373). In n=197 patients (10.6%), active treatment was discontinued after hospital admission (no aneurysm occlusion attempted), and this cohort was excluded from analysis of the main statistical model. In the remaining n=1669 patients, the rate of in-hospital mortality was 13.9% (n=232). Strong independent predictors of in-hospital mortality were rebleeding (aOR, 7.69; 95% confidence interval, 3.00-19.71; P<0.001), cerebral infarction attributable to delayed cerebral ischemia (aOR, 3.66; 95% confidence interval, 1.94-6.89; P<0.001), intraventricular hemorrhage (aOR, 2.65; 95% confidence interval, 1.38-5.09; P=0.003), and new infarction post-treatment (aOR, 2.57; 95% confidence interval, 1.43-4.62; P=0.002). CONCLUSIONS: Several-and among them modifiable-factors seem to be associated with in-hospital mortality after aneurysmal subarachnoid hemorrhage. Our data suggest that strategies aiming to reduce the risk of rebleeding are most promising in patients where active treatment is initially pursued. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT03245866.

Robot guidance for percutaneous minimally invasive placement of pedicle screws for pyogenic spondylodiscitis is associated with lower rates of wound breakdown compared to conventional fluoroscopy-guided instrumentation.

Postoperative wound healing can pose a problem in patients undergoing instrumented surgery for pyogenic spondylodiscitis. Robotic guidance allows the minimally invasive placement of pedicle screws in the thoracolumbar spine. We assessed whether using this technique to perform minimally invasive surgery had an impact on wound healing in patients with pyogenic spondylodiscitis when compared to conventional open fluoroscopy-guided surgery. We reviewed charts of 206 consecutive patients who underwent instrumentation for pyogenic spondylodiscitis. The need for wound revision was the primary outcome measure. Patient variables and comorbidities as well as surgical technique (robotic versus fluoroscopy-guided) were analyzed. We also compared fluoroscopy times between the two groups. Multivariate regression analysis was performed to identify predictors of wound breakdown. A total of 206 patients underwent surgery for spondylodiscitis. Robotic surgical assistance was used for percutaneous instrumentation in 47.6% of cases (n = 98). Wound healing problems requiring revision occurred in 30 out of 206 patients (14.6%). Univariate analysis revealed a potential association of wound breakdown with (1) robotic technique, (2) age > 70 years, and (3) the presence of methicillin-resistant Staphylococcus aureus. After multivariate correction however, only robotic technique retained significance with an odds ratio of 0.39 (CI 95% 0.16-0.94; p = 0.035). Wound revision was required in eight out of 98 patients (8.1%) in the robot group and 22/108 (20%) in the conventional surgery group. Fluoroscopy times were significantly lower in the robot group with a mean of 123 ± 86 s in comparison with a mean of 157 ± 99 s in the conventional group (p = 0.014). While initially designed to improve the accuracy of pedicle screw placement, robot-assisted minimally invasive technique had a tangible effect on both radiation exposure and the rate of wound breakdown in patients with pyogenic spondylodiscitis in our large single-center study.

Predictors of ventricular tension pneumocephalus after posterior fossa surgery in the sitting position.

BACKGROUND: Ventricular pneumocephalus is a rare but potentially life-threatening complication of cranial surgery in the sitting position. OBJECTIVE: The objective of the study is to assess the incidence and risk factors of postoperative ventricular pneumocephalus. METHODS: We performed a retrospective chart review of 307 consecutive patients (147 men, 160 women) treated at our institution by intracranial surgery in the sitting position from January 2010 to October 2014. Ventricular air entrapment with lack of arousal or neurologic deterioration requiring external ventriculostomy (EVD) was defined as ventricular tension pneumocephalus (VTP). Demographic variables were recorded along with radiological and clinical data. The occurrence of pneumocephalus was correlated with patient-related and surgical variables. RESULTS: VTP was observed in 12 cases (3.9%). These patients had higher intraventricular air volumes (48.5 cm3 (CI 95% [29.06-67.86])) compared to asymptomatic patients (7.4 cm3 (CI 95% [5.43-9.48])). Opening of the fourth ventricle was the most potent predictor of VTP (OR = 34.7, CI 95% [4.4-273.5], p = 0.001). In patients undergoing no additional treatment for pneumocephalus, ventricular air volume declined to an average of 41.7% of the initial postoperative volume on postoperative day 3. CONCLUSIONS: Entrapment of intracranial and particularly ventricular air requiring emergent EVD occurred in 3.9% cases of intracranial surgery in the sitting position. Especially the opening of the fourth ventricle was associated with the development of VTP, which should warrant particularly diligent postoperative observation of these patients. In cases without neurological symptoms, the rate of spontaneous air resorption is sufficiently high to warrant expectant management.

Accuracy of robot-guided versus freehand fluoroscopy-assisted pedicle screw insertion in thoracolumbar spinal surgery.

OBJECTIVE The quest to improve the safety and accuracy and decrease the invasiveness of pedicle screw placement in spine surgery has led to a markedly increased interest in robotic technology. The SpineAssist from Mazor is one of the most widely distributed robotic systems. The aim of this study was to compare the accuracy of robot-guided and conventional freehand fluoroscopy-guided pedicle screw placement in thoracolumbar surgery. METHODS This study is a retrospective series of 169 patients (83 women [49%]) who underwent placement of pedicle screw instrumentation from 2007 to 2015 in 2 reference centers. Pathological entities included degenerative disorders, tumors, and traumatic cases. In the robot-assisted cohort (98 patients, 439 screws), pedicle screws were inserted with robotic assistance. In the freehand fluoroscopy-guided cohort (71 patients, 441 screws), screws were inserted using anatomical landmarks and lateral fluoroscopic guidance. Patients treated before 2009 were included in the fluoroscopy cohort, whereas those treated since mid-2009 (when the robot was acquired) were included in the robot cohort. Since then, the decision to operate using robotic assistance or conventional freehand technique has been based on surgeon preference and logistics. The accuracy of screw placement was assessed based on the Gertzbein-Robbins scale by a neuroradiologist blinded to treatment group. The radiological slice with the largest visible deviation from the pedicle was chosen for grading. A pedicle breach of 2 mm or less was deemed acceptable (Grades A and B) while deviations greater than 2 mm (Grades C, D, and E) were classified as misplacements. RESULTS In the robot-assisted cohort, a perfect trajectory (Grade A) was observed for 366 screws (83.4%). The remaining screws were Grades B (n = 44 [10%]), C (n = 15 [3.4%]), D (n = 8 [1.8%]), and E (n = 6 [1.4%]). In the fluoroscopy-guided group, a completely intrapedicular course graded as A was found in 76% (n = 335). The remaining screws were Grades B (n = 57 [12.9%]), C (n = 29 [6.6%]), D (n = 12 [2.7%]), and E (n = 8 [1.8%]). The proportion of non-misplaced screws (corresponding to Gertzbein-Robbins Grades A and B) was higher in the robot-assisted group (93.4%) than the freehand fluoroscopy group (88.9%) (p = 0.005). CONCLUSIONS The authors' retrospective case review found that robot-guided pedicle screw placement is a safe, useful, and potentially more accurate alternative to the conventional freehand technique for the placement of thoracolumbar spinal instrumentation.