Management of Patients undergoing Elective Craniotomy under Antiplatelet or Anticoagulation Therapy: An International Survey of Practice.

BACKGROUND: The literature concerning the management of antiplatelet (AP) and anticoagulation (AC) medication in the perioperative phase of craniotomy remains scarce. The aim of this international survey was to investigate the current practice among neurosurgeons regarding their perioperative management of AP and AC medication. METHODS: We distributed an online survey to neurosurgeons worldwide with questions concerning their perioperative practice with AP and AC medication in patients undergoing craniotomy. Descriptive statistics were performed. RESULTS: A total of 130 replies were registered. The majority of responders practice neurosurgery in Europe (79%) or high-income countries (79%). Responders reported in 58.9 and 48.8% to have institutional guidelines for the perioperative management of AP and AC medication. Preoperative interruption time was reported heterogeneously for the different types of AP and AC medication with 40.4% of responders interrupting aspirin (ASA) for 4 to 6 days and 45.7% interrupting clopidogrel for 6 to 8 days. Around half of the responders considered ASA safe to be continued or resumed within 3 days for bypass (55%) or vascular (49%) surgery, but only few for skull base or other tumor craniotomies in general (14 and 26%, respectively). Three quarters of the responders (74%) did not consider AC safe to be continued or resumed early (within 3 days) for any kind of craniotomy. ASA was considered to have the lowest risk of bleeding. Nearly all responders (93%) agreed that more evidence is needed concerning AP and AC management in neurosurgery. CONCLUSION: Worldwide, the perioperative management of AP and AC medication is very heterogeneous among neurosurgeons.

Parkinson's disease may disrupt overlapping subthalamic nucleus and pallidal motor networks.

There is an ongoing debate about differential clinical outcome and associated adverse effects of deep brain stimulation (DBS) in Parkinson's disease (PD) targeting the subthalamic nucleus (STN) or the globus pallidus pars interna (GPi). Given that functional connectivity profiles suggest beneficial DBS effects within a common network, the empirical evidence about the underlying anatomical circuitry is still scarce. Therefore, we investigate the STN and GPi-associated structural covariance brain patterns in PD patients and healthy controls. We estimate GPi's and STN's whole-brain structural covariance from magnetic resonance imaging (MRI) in a normative mid- to old-age community-dwelling cohort (n = 1184) across maps of grey matter volume, magnetization transfer (MT) saturation, longitudinal relaxation rate (R1), effective transversal relaxation rate (R2*) and effective proton density (PD*). We compare these with the structural covariance estimates in patients with idiopathic PD (n = 32) followed by validation using a reduced size controls' cohort (n = 32). In the normative data set, we observed overlapping spatially distributed cortical and subcortical covariance patterns across maps confined to basal ganglia, thalamus, motor, and premotor cortical areas. Only the subcortical and midline motor cortical areas were confirmed in the reduced size cohort. These findings contrasted with the absence of structural covariance with cortical areas in the PD cohort. We interpret with caution the differential covariance maps of overlapping STN and GPi networks in patients with PD and healthy controls as correlates of motor network disruption. Our study provides face validity to the proposed extension of the currently existing structural covariance methods based on morphometry features to multiparameter MRI sensitive to brain tissue microstructure.

Successful weaning versus permanent cerebrospinal fluid diversion after aneurysmal subarachnoid hemorrhage: post hoc analysis of a Swiss multicenter study.

OBJECTIVE: Acute hydrocephalus is a frequent complication after aneurysmal subarachnoid hemorrhage (aSAH). Among patients needing CSF diversion, some cannot be weaned. Little is known about the comparative neurological, neuropsychological, and health-related quality-of-life (HRQOL) outcomes in patients with successful and unsuccessful CSF weaning. The authors aimed to assess outcomes of patients by comparing those with successful and unsuccessful CSF weaning; the latter was defined as occurring in patients with permanent CSF diversion at 3 months post-aSAH. METHODS: The authors included prospectively recruited alert (i.e., Glasgow Coma Scale score 13-15) patients with aSAH in this retrospective study from six Swiss neurovascular centers. Patients underwent serial neurological (National Institutes of Health Stroke Scale), neuropsychological (Montreal Cognitive Assessment), disability (modified Rankin Scale), and HRQOL (EuroQol-5D) examinations at < 72 hours, 14-28 days, and 3 months post-aSAH. RESULTS: Of 126 included patients, 54 (42.9%) developed acute hydrocephalus needing CSF diversion, of whom 37 (68.5%) could be successfully weaned and 17 (31.5%) required permanent CSF diversion. Patients with unsuccessful weaning were older (64.5 vs 50.8 years, p = 0.003) and had a higher rate of intraventricular hemorrhage (52.9% vs 24.3%, p = 0.04). Patients who succeed in restoration of physiological CSF dynamics improve on average by 2 points on the Montreal Cognitive Assessment between 48-72 hours and 14-28 days, whereas those in whom weaning fails worsen by 4 points (adjusted coefficient 6.80, 95% CI 1.57-12.04, p = 0.01). They show better neuropsychological recovery between 48-72 hours and 3 months, compared to patients in whom weaning fails (adjusted coefficient 7.60, 95% CI 3.09-12.11, p = 0.02). Patients who receive permanent CSF diversion (ventriculoperitoneal shunt) show significant neuropsychological improvement thereafter, catching up the delay in neuropsychological improvement between 14-28 days and 3 months post-aSAH. Neurological, disability, and HRQOL outcomes at 3 months were similar. CONCLUSIONS: These results show a temporary but clinically meaningful cognitive benefit in the first weeks after aSAH in successfully weaned patients. The resolution of this difference over time may be due to the positive effects of permanent CSF diversion and underlines its importance. Patients who do not show progressive neuropsychological improvement after weaning should be considered for repeat CT imaging to rule out chronic (untreated) hydrocephalus.

Impact of Very Small Aneurysm Size and Anterior Communicating Segment Location on Outcome after Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Very small anterior communicating artery aneurysms (vsACoA) of <5 mm in size are detected in a considerable number of patients with aneurysmal subarachnoid hemorrhage (aSAH). Single-center studies report that vsACoA harbor particular risks when treated. OBJECTIVE: To assess the clinical and radiological outcome(s) of patients with aSAH diagnosed with vsACoA after aneurysm treatment and at discharge. METHODS: Information on n = 1868 patients was collected in the Swiss Subarachnoid Hemorrhage Outcome Study registry between 2009 and 2014. The presence of a new focal neurological deficit at discharge, functional status (modified Rankin scale), mortality rates, and procedural complications (in-hospital rebleeding and presence of a new stroke on computed tomography) was assessed for vsACoA and compared with the results observed for aneurysms in other locations and with diameters of 5 to 25 mm. RESULTS: This study analyzed n = 1258 patients with aSAH, n = 439 of which had a documented ruptured ACoA. ACoA location was found in 38% (n = 144/384) of all very small ruptured aneurysms. A higher in-hospital bleeding rate was found in vsACoA compared with non-ACoA locations (2.8 vs 2.1%), especially when endovascularly treated (2.1% vs 0.5%). In multivariate analysis, aneurysm size of 5 to 25 mm, and not ACoA location, was an independent risk factor for a new focal neurological deficit and a higher modified Rankin scale at discharge. Neither very small aneurysm size nor ACoA location was associated with higher mortality rates at discharge or the occurrence of a peri-interventional stroke. CONCLUSION: Very small ruptured ACoA have a higher in-hospital rebleeding rate but are not associated with worse morbidity or mortality.

Severe Neuro-COVID is associated with peripheral immune signatures, autoimmunity and neurodegeneration: a prospective cross-sectional study.

Growing evidence links COVID-19 with acute and long-term neurological dysfunction. However, the pathophysiological mechanisms resulting in central nervous system involvement remain unclear, posing both diagnostic and therapeutic challenges. Here we show outcomes of a cross-sectional clinical study (NCT04472013) including clinical and imaging data and corresponding multidimensional characterization of immune mediators in the cerebrospinal fluid (CSF) and plasma of patients belonging to different Neuro-COVID severity classes. The most prominent signs of severe Neuro-COVID are blood-brain barrier (BBB) impairment, elevated microglia activation markers and a polyclonal B cell response targeting self-antigens and non-self-antigens. COVID-19 patients show decreased regional brain volumes associating with specific CSF parameters, however, COVID-19 patients characterized by plasma cytokine storm are presenting with a non-inflammatory CSF profile. Post-acute COVID-19 syndrome strongly associates with a distinctive set of CSF and plasma mediators. Collectively, we identify several potentially actionable targets to prevent or intervene with the neurological consequences of SARS-CoV-2 infection.

Longitudinal neuropsychological assessment after aneurysmal subarachnoid hemorrhage and its relationship with delayed cerebral ischemia: a prospective Swiss multicenter study.

OBJECTIVE: While prior retrospective studies have suggested that delayed cerebral ischemia (DCI) is a predictor of neuropsychological deficits after aneurysmal subarachnoid hemorrhage (aSAH), all studies to date have shown a high risk of bias. This study was designed to determine the impact of DCI on the longitudinal neuropsychological outcome after aSAH, and importantly, it includes a baseline examination after aSAH but before DCI onset to reduce the risk of bias. METHODS: In a prospective, multicenter study (8 Swiss centers), 112 consecutive alert patients underwent serial neuropsychological assessments (Montreal Cognitive Assessment [MoCA]) before and after the DCI period (first assessment, < 72 hours after aSAH; second, 14 days after aSAH; third, 3 months after aSAH). The authors compared standardized MoCA scores and determined the likelihood for a clinically meaningful decline of ≥ 2 points from baseline in patients with DCI versus those without. RESULTS: The authors screened 519 patients, enrolled 128, and obtained complete data in 112 (87.5%; mean [± SD] age 53.9 ± 13.9 years; 66.1% female; 73% World Federation of Neurosurgical Societies [WFNS] grade I, 17% WFNS grade II, 10% WFNS grades III-V), of whom 30 (26.8%) developed DCI. MoCA z-scores were worse in the DCI group at baseline (-2.6 vs -1.4, p = 0.013) and 14 days (-3.4 vs -0.9, p < 0.001), and 3 months (-0.8 vs 0.0, p = 0.037) after aSAH. Patients with DCI were more likely to experience a decline of ≥ 2 points in MoCA score at 14 days after aSAH (adjusted OR [aOR] 3.02, 95% CI 1.07-8.54; p = 0.037), but the likelihood was similar to that in patients without DCI at 3 months after aSAH (aOR 1.58, 95% CI 0.28-8.89; p = 0.606). CONCLUSIONS: Aneurysmal SAH patients experiencing DCI have worse neuropsychological function before and until 3 months after the DCI period. DCI itself is responsible for a temporary and clinically meaningful decline in neuropsychological function, but its effect on the MoCA score could not be measured at the time of the 3-month follow-up in patients with low-grade aSAH with little or no impairment of consciousness. Whether these findings can be extrapolated to patients with high-grade aSAH remains unclear. Clinical trial registration no.: NCT03032471 (ClinicalTrials.gov).

Preclinical and clinical role of interleukin-6 in the development of delayed cerebral vasospasm and neuronal cell death after subarachnoid hemorrhage: towards a potential target therapy?

Delayed cerebral vasospasm (DCVS), early brain injury (EBI), and delayed cerebral ischemia (DCI) are devastating complications after aneurysmal subarachnoid hemorrhage (SAH). Interleukin (IL)-6 seems to be an important interleukin in the inflammatory response after SAH, and many studies describe a strong correlation between IL-6 and worse outcome. The aim of this study was to systematically review preclinical and clinical studies that evaluated systemic and cerebral IL-6 levels after SAH and their relation to DCVS, neuronal cell death, and DCI. We conducted two systematic literature searches using PubMed to identify preclinical and clinical studies evaluating the role of IL-6 after SAH. Suitable articles were selected based on predefined eligibility criteria following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A total of 61 and 30 preclinical and clinical articles, respectively, were included in the systematic reviews. Of the preclinical studies in which IL-6 was measured in cerebrospinal fluid (CSF), parenchyma, and systemically, 100%, 94.4%, and 81.3%, respectively, showed increased expression of IL-6 after SAH. Preclinical results were mirrored by clinical findings in which elevated levels of IL-6 in CSF and plasma were found after SAH, correlating with DCVS, DCI, and worse outcome. Only two preclinical studies analyzed the direct inhibition of IL-6, which resulted in reduced DCVS and neuronal cell death. IL-6 is a marker of intracranial inflammation and plays a role in the pathophysiology of DCVS and DCI after SAH in preclinical animal models and clinical studies. Its inhibition might have therapeutic potential to improve the outcome of SAH patients.

Longer survival of glioblastoma complicated by bacterial infections after surgery: what is known today.

INTRODUCTION: Glioblastoma is the most common primary brain tumor in adults with the worst overall survival. Post-craniotomy intracranial infections are not infrequent after surgery; however, their impact on overall survival of glioblastoma patients remains unclear. Here we report the case of an unusual longer survival of a glioblastoma patient affected by multiple infections and the review of the literature on this topic. EVIDENCE ACQUISITION: PubMed, Embase and Cochrane search engines were reviewed for papers describing outcome of patients suffering from glioblastoma and associated cerebral infections. EVIDENCE SYNTHESIS: Four papers accounting a total of 29 patients met the eligibility criteria. Staphylococcus aureus and Staphylococcus epidermidis resulted the most common bacteria causing post-craniotomy intracranial infections in brain tumor patients. The overall median survival rate was 18±18.12 months when adding all 29 patients. Only one study described a significant higher survival rate for the infected group. CONCLUSIONS: Glioblastoma is the most frequent malignant brain tumor with a very poor outcome/survival. In the literature few cases described an exceptional longer survival often associated with a postoperative infection. To date, the pathophysiology behind this longer survival remains unclear, but it seems that Staphylococcus species could have an influence on the progression of this aggressive brain tumor.

Mortality and Outcome in Patients Older Than 80 Years of Age Undergoing Burr-Hole Drainage of Chronic Subdural Hematoma.

OBJECTIVE: Chronic subdural hematoma is frequently seen within the elderly population and neurosurgeons are confronted with patients older than 80 years presenting with symptomatic chronic subdural hematoma. However, data on surgical outcome are scarce. The aim of this study is to analyze the mortality and outcome after burr-hole drainage in patients older than 80 years. METHODS: This is a single-center retrospective study including patients who underwent burr-hole drainage of chronic subdural hematoma between the years 2016 and 2019. The cohort was divided into 3 age groups (80-84 years; 85-89 years; >90 years). Primary outcome was 30-day and overall mortality, whereas secondary outcome measures were recurrence rates, postoperative bleeding rates, and outcome measured by the modified ranking scale. Uni- and multivariate analysis was conducted to assess for potential risk factors for mortality, recurrence and postoperative bleeding rates. RESULTS: In total, 107 patients with a mean age of 85.5 ± 3.9 years were included. Mortality rate was less than 10% in each group, showing no significant difference between them (P = 0.455). No significant difference in recurrence and postoperative bleeding rates was seen (P = 0.491 and P = 0.532). Modified Ranking scale score differed significantly at release, whereas at follow-up no difference was seen. After uni- and multivariate analysis, age was not correlated with higher recurrence, postoperative bleeding, or mortality rates. Preoperative midline shift was found to be an independent risk factor for recurrence. CONCLUSIONS: In patients older than 80 years undergoing burr-hole drainage for chronic subdural hematoma, age was not directly correlated with higher recurrence, postoperative bleeding, or mortality rates.

Clinical and radiological outcomes in relation with the anatomical orientation of clipped middle cerebral artery bifurcation aneurysms.

BACKGROUND: The middle cerebral artery (MCA) bifurcation represents the most frequent location for intracranial aneurysms. Often, the aneurysmal dome can hide the origin of perforating arteries from the M1 segment during the surgical clipping causing ischemic lesions and worse clinical outcome. The aim of this paper is to analyze the association between the orientation of the aneurysm sac and the clinical and radiological outcomes after surgical clipping. METHODS: Data from 50 MCA bifurcation clipped aneurysms in 47 patients were collected retrospectively. Three different groups were identified according to the aneurysmal sac orientation: anterior-inferior, posterior and superior. A possible association between the aneurysmal sac projection and the outcome was searched through a univariable logistic regression analysis. RESULTS: Statistical analysis showed significant correlation between the radiologic evidence of post-operative ischemia in the posterior group (p = 0.046, RR = 1.65) and an increased risk in the superior orientation group (p = 0.145, RR = 1.38). The anterior-inferior group was, instead, significantly associated with no evidence of radiologic ischemia (p = 0.0019, RR = 0.58). CONCLUSION: The orientation of the aneurysmal dome and sac represents a fundamental feature to be considered during the surgical clipping of the MCA aneurysms. Indeed, its posterior and superior projection is associated with a higher incidence of radiologic ischemic lesions due to the origin of perforating arteries from M1 segment behind the aneurysmal sac. The anterior-inferior orientation, on the contrary, is associated with a lower risk.

Development of a Complication- and Treatment-Aware Prediction Model for Favorable Functional Outcome in Aneurysmal Subarachnoid Hemorrhage Based on Machine Learning.

BACKGROUND: Current prognostic tools in aneurysmal subarachnoid hemorrhage (aSAH) are constrained by being primarily based on patient and disease characteristics on admission. OBJECTIVE: To develop and validate a complication- and treatment-aware outcome prediction tool in aSAH. METHODS: This cohort study included data from an ongoing prospective nationwide multicenter registry on all aSAH patients in Switzerland (Swiss SOS [Swiss Study on aSAH]; 2009-2015). We trained supervised machine learning algorithms to predict a binary outcome at discharge (modified Rankin scale [mRS] ≤ 3: favorable; mRS 4-6: unfavorable). Clinical and radiological variables on admission ("Early" Model) as well as additional variables regarding secondary complications and disease management ("Late" Model) were used. Performance of both models was assessed by classification performance metrics on an out-of-sample test dataset. RESULTS: Favorable functional outcome at discharge was observed in 1156 (62.0%) of 1866 patients. Both models scored a high accuracy of 75% to 76% on the test set. The "Late" outcome model outperformed the "Early" model with an area under the receiver operator characteristics curve (AUC) of 0.85 vs 0.79, corresponding to a specificity of 0.81 vs 0.70 and a sensitivity of 0.71 vs 0.79, respectively. CONCLUSION: Both machine learning models show good discrimination and calibration confirmed on application to an internal test dataset of patients with a wide range of disease severity treated in different institutions within a nationwide registry. Our study indicates that the inclusion of variables reflecting the clinical course of the patient may lead to outcome predictions with superior predictive power compared to a model based on admission data only.

Early permanent cerebrospinal fluid diversion in aneurysmal subarachnoid hemorrhage: does a lower rate of nosocomial meningitis outweigh the risk of delayed cerebral vasospasm related morbidity?

Objective: Early permanent cerebrospinal fluid (CSF) diversion for hydrocephalus during the first 2 weeks after aneurysmal subarachnoid hemorrhage (aSAH) shortens the duration of external ventricular drainage (EVD) and reduces EVD-associated infections (EVDAI). The objective of this study was to detect any association with symptomatic delayed cerebral vasospasm (DCVS), or delayed cerebral ischemia (DCI) by the time of hospital discharge. Methods: We used a single-center dataset of aSAH patients who had received a permanent CSF diversion. We compared an 'early group' in which the procedure was performed up to 14 days after the ictus, to a 'late group' in which it was performed from the 15th day onward. Results: Among 274 consecutive aSAH patients, 39 (14%) had a permanent CSF diversion procedure with a silver-coated EVD. While the blood clot burden was similarly distributed, patients with early permanent CSF diversion (20 out of 39; 51%) had higher levels of consciousness on admission. Early permanent CSF diversion was associated with less colonized catheter, a shorter duration of extracorporeal CSF diversion (OR 0.73, 95%CI 0.58-0.92 per EVD day), and a lower rate of EVDAI (OR 0.08, 95%CI 0.01-0.80). The occurrence of CSF diversion device obstruction, the rate of symptomatic DCVS or detected DCI on computed tomography and the likelihood of a poor outcome at discharge did not differ between the two groups. Discussion: Early permanent CSF diversion lowers the occurrence of catheter colonization and infectious complication without affecting DCVS-related morbidity in good-grade aSAH patients. These findings need confirmation in larger prospective multicenter cohorts. Abbreviations: aSAH: aneurysmal subarachnoid hemorrhage; BNI: Barrow Neurological Institute Scale; CSF: Cerebrospinal fluid; DCVS: Delayed Cerebral Vasospasm; DCI: Delayed Cortical Ischemia; EKNZ: Ethik-Kommission Nordwest Schweiz; EVD: External ventricular drain; EVDAI: External ventricular drain-associated infections; GCS: Glasgow Coma Scale; IRB: Institutional Review Board; IVH: Inraventricular hemorrhage; mRS: Modified Rankin Scale; SOS: Swiss Study of Subarachnoid Hemorrhage Registry; WFNS: World Federation Neurological-Surgeon Scale.

Bilateral persistent stapedial arteries associated with unilateral moyamoya disease: a particular anatomic variant.

PURPOSE: The persistence of the stapedial artery is a rare vascular variant that could explain the origin of the middle meningeal artery from the petrous segment of the internal carotid artery. The anatomic variations are illustrated and a summary of the possible hypothesis of the origin of the middle meningeal artery from the internal carotid artery is discussed, analysing the embryological works of the Carnegie Institute and the vascular development of the middle meningeal. METHODS AND RESULTS: The authors present a young patient showing a particular vascular variant on diagnostic imaging. These showed a bilateral internal carotid artery that gives origin of the middle meningeal artery in a patient affected by moyamoya disease. A literature review was performed to analyze the particular variant of the radiologic anatomy. CONCLUSION: The internal carotid artery origin of the middle meningeal artery is a wonderful anatomic variant that permits to understand the complex embryological development and then involution of the stapedial artery.

Patterns of care for ruptured aneurysms of the middle cerebral artery: analysis of a Swiss national database (Swiss SOS).

OBJECTIVE: The objective of this study was to determine patterns of care and outcomes in ruptured intracranial aneurysms (IAs) of the middle cerebral artery (MCA) in a contemporary national cohort. METHODS: The authors conducted a retrospective analysis of prospective data from a nationwide multicenter registry of all aneurysmal subarachnoid hemorrhage (aSAH) cases admitted to a tertiary care neurosurgical department in Switzerland in the years 2009-2015 (Swiss Study on Aneurysmal Subarachnoid Hemorrhage [Swiss SOS]). Patterns of care and outcomes at discharge and the 1-year follow-up in MCA aneurysm (MCAA) patients were analyzed and compared with those in a control group of patients with IAs in locations other than the MCA (non-MCAA patients). Independent predictors of a favorable outcome (modified Rankin Scale score ≤ 3) were identified, and their effect size was determined. RESULTS: Among 1866 consecutive aSAH patients, 413 (22.1%) harbored an MCAA. These MCAA patients presented with higher World Federation of Neurosurgical Societies grades (p = 0.007), showed a higher rate of concomitant intracerebral hemorrhage (ICH; 41.9% vs 16.7%, p < 0.001), and experienced delayed cerebral ischemia (DCI) more frequently (38.9% vs 29.4%, p = 0.001) than non-MCAA patients. After adjustment for confounders, patients with MCAA were as likely as non-MCAA patients to experience DCI (aOR 1.04, 95% CI 0.74-1.45, p = 0.830). Surgical treatment was the dominant treatment modality in MCAA patients and at a significantly higher rate than in non-MCAA patients (81.7% vs 36.7%, p < 0.001). An MCAA location was a strong independent predictor of surgical treatment (aOR 8.49, 95% CI 5.89-12.25, p < 0.001), despite statistical adjustment for variables traditionally associated with surgical treatment, such as (space-occupying) ICH (aOR 1.73, 95% CI 1.23-2.45, p = 0.002). Even though MCAA patients were less likely to die during the acute hospitalization (aOR 0.52, 0.30-0.91, p = 0.022), their rate of a favorable outcome was lower at discharge than that in non-MCAA patients (55.7% vs 63.7%, p = 0.003). At the 1-year follow-up, 68.5% and 69.6% of MCAA and non-MCAA patients, respectively, had a favorable outcome (p = 0.676). CONCLUSIONS: Microsurgical occlusion remains the predominant treatment choice for about 80% of ruptured MCAAs in a European industrialized country. Although patients with MCAAs presented with worse admission grades and greater rates of concomitant ICH, in-hospital mortality was lower and long-term disability was comparable to those in patients with non-MCAA.

Supraorbital approach through eyebrow skin incision for aneurysm clipping: how I do it.

BACKGROUND: Surgery has been in a huge development where the aim is to achieve same or better results with less complication in a less invasive way; these minimal approaches can be applied in a very safe way to aneurysmal neurosurgery. METHOD: Images are studied to optimize the patient positioning and the surgical roadmap. After the positioning, the skin incision, craniotomy, and dura incision are performed and intradural lesion is reached. A watertight closure is performed under the microscope. CONCLUSION: The keyhole approach requires some adaption from the side of the surgeon and can be performed only in cases envisioned to have no increased risk for the patient.

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.