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.

Early fusion outcome after surgical treatment of single-level and multi-level pyogenic spondylodiscitis: experience at a level 1 center for spinal surgery-a single center cohort study.

STUDY DESIGN: Retrospective single center cohort study. PURPOSE: Spinal instrumentation in combination with antibiotic therapy is a treatment option for acute or chronic pyogenic spondylodiscitis (PSD). This study compares the early fusion outcome for multi-level and single-level PSD after urgent surgical treatment with interbody fusion in combination with fixation. METHODS: This is a retrospective cohort study. Over a 10 year period at a single institution, all surgically treated patients received surgical debridement, fusion und fixation of the spine to treat PSD. Multi-level cases were either adjacent to each other on the spine or distant. Fusion rates were assessed at 3 and 12 months after surgery. We analyzed demographic data, ASA status, duration of surgery, location and length of spine affected, Charlson comorbidity index (CCI), and early complications. RESULTS: A total of 172 patients were included. Of these, 114 patients suffered from single-level and 58 from multi-level PSD. The most frequent location was the lumbar spine (54.0%) followed by the thoracic spine (18.0%). The PSD was adjacent in 19.0% and distant in 81.0% of multi-level cases. Fusion rates at the 3 month follow-up did not differ among the multi-level group (p = 0.27 for both adjacent and distant sites). In the single-level group, sufficient fusion was achieved in 70.2% of cases. Pathogen identification was possible 58.5% of the time. CONCLUSIONS: Surgical treatment of multi-level PSD is a safe option. Our study demonstrates that there was no significant difference in early fusion outcomes between single-level and multi-level PSD, whether adjacent or distant.

PrImary decompressive Craniectomy in AneurySmal Subarachnoid hemOrrhage (PICASSO) trial: study protocol for a randomized controlled trial.

BACKGROUND: Poor-grade aneurysmal subarachnoid hemorrhage (SAH) is associated with poor neurological outcome and high mortality. A major factor influencing morbidity and mortality is brain swelling in the acute phase. Decompressive craniectomy (DC) is currently used as an option in order to reduce intractably elevated intracranial pressure (ICP). However, execution and optimal timing of DC remain unclear. METHODS: PICASSO resembles a multicentric, prospective, 1:1 randomized standard treatment-controlled trial which analyzes whether primary DC (pDC) performed within 24 h combined with the best medical treatment in patients with poor-grade SAH reduces mortality and severe disability in comparison to best medical treatment alone and secondary craniectomy as ultima ratio therapy for elevated ICP. Consecutive patients presenting with poor-grade SAH, defined as grade 4-5 according to the World Federation of Neurosurgical Societies (WFNS), will be screened for eligibility. Two hundred sixteen patients will be randomized to receive either pDC additional to best medical treatment or best medical treatment alone. The primary outcome is the clinical outcome according to the modified Rankin Scale (mRS) at 12 months, which is dichotomized to favorable (mRS 0-4) and unfavorable (mRS 5-6). Secondary outcomes include morbidity and mortality, time to death, length of intensive care unit (ICU) stay and hospital stay, quality of life, rate of secondary DC due to intractably elevated ICP, effect of size of DC on outcome, use of duraplasty, and complications of DC. DISCUSSION: This multicenter trial aims to generate the first confirmatory data in a controlled randomized fashion that pDC improves the outcome in a clinically relevant endpoint in poor-grade SAH patients. TRIAL REGISTRATION: DRKS DRKS00017650. Registered on 09 June 2019.

Postoperative prolonged mechanical ventilation correlates to poor survival in patients with surgically treated spinal metastasis.

Objective: Patients with spinal metastasis (SM) are at advanced stages of systemic cancer disease. Surgical therapy for SM is a common treatment modality enabling histopathological diagnosis and the prevention of severe neurological deficits. However, surgery for SM in this vulnerable patient cohort may require prolonged postoperative intensive care treatment, which could adversely affect the anticipated benefit of the surgery. We therefore assessed postoperative prolonged mechanical ventilation (PMV) as an indicator for intensive care treatment with regard to potential correlations with early postoperative mortality and overall survival (OS). Methods: Between 2015 and 2019, 198 patients were surgically treated for SM at the author´s neurosurgical department. PMV was defined as postoperative mechanical ventilation of more than 24 hours. A multivariate analysis was performed to identify pre- and perioperative collectable predictors for 30 days mortality. Results: Twenty out of 198 patients (10%) with SM suffered from postoperative PMV. Patients with PMV exhibited a median OS rate of 1 month compared to 12 months for patients without PMV (p < 0.0001). The 30 days mortality was 70% and after one year 100%. The multivariate analysis identified "PMV > 24 hrs" (p < 0.001, OR 0.3, 95% CI 0.02-0.4) as the only significant and independent predictor for 30 days mortality (Nagelkerke's R2 0.38). Conclusions: Our data indicate postoperative PMV to significantly correlate to high early postoperative mortality rates as well as to poor OS in patients with surgically treated SM. These findings might encourage the initiation of further multicenter studies to comprehensively investigate PMV as a so far underestimated negative prognostic factor in the course of surgical treatment for SM.

Delayed Cerebral Ischemia after Aneurysmal Subarachnoid Hemorrhage: The Results of Induced Hypertension Only after the IMCVS Trial-A Prospective Cohort Study.

Delayed cerebral ischemia (DCI) is a predictor of poor outcome after aneurysmal subarachnoid hemorrhage (SAH). Treatment strategies vary and include induced hypertension and invasive endovascular treatment. After the IMCVS trial (NCT01400360), which failed to demonstrate a benefit of endovascular treatment for cerebral vasospasm (CVS) and resulted in a significantly worse outcome, we changed our treatment policy in patients with diagnosed CVS to induced hypertension only, and we present our prospective results in the subgroup of SAH patients meeting inclusion criteria of the IMCVS trial. All patients underwent screening for DIND when conscious and for CVS using CT-A/-P at day 6-8 after SAH. In the case of CVS, arterial hypertension was induced and continued until re-assessment. In total, 149 of 303 patients developed CVS. DCI developed in 35 patients (23.5%). In multivariate analyses, CVS was a predictor for the development of new infarctions. Poor admission status, re-bleeding before treatment, and DCI predicted poor outcome. The omittance of invasive endovascular rescue therapies in SAH patients with CVS, additional to induced hypertension, does not lead to a higher rate of DCI. Potential benefits of additional endovascular treatment for CVS need to be addressed in further studies searching for a subgroup of patients who may benefit.

Safety Evaluation of Cervical Dorsal Instrumentation in Geriatric Patients: Experience at a Level 1 Center for Spinal Surgery-A Single Center Cohort Study.

Objective: Dorsal instrumentation of the cervical spine is an established treatment in spine surgery. However, careful planning is required, particularly in elderly patients. This study evaluates early clinical outcomes in geriatric patients undergoing complex spine surgery. Methods: In this retrospective, single center cohort study, we included all geriatric patients (aged ≥65 years) who underwent dorsal instrumentation between January 2013 and December 2020. We analyzed postoperative complications and the 30-day in-hospital mortality rate. Furthermore, the Charlson comorbidity index (CCI) and Clavien-Dindo grading system (CDG) were used to assess the patients' comorbidity burden. Results: In total, 153 patients were identified and included. The mean age of patients was 78 years (SD ± 7). Traumatic injury (53.6%) was the most common reason for surgery. 60.8% of the patients underwent dorsal instrumentation with 3 or more levels. The most common comorbidities were arterial hypertension (64%), diabetes mellitus (22.2%), coronary heart disease and atrial fibrillation (19.6%). The most common adverse event (AE) was pneumonia (4%) and the most common surgery-related complication was wound infection (5.2%). Among patients categorized as high risk for AE (CCI > 5), 14.6% suffered a postoperative AE. In our univariate analysis, we found no risk factors for high rates of complications or mortality. Conclusion: Our data demonstrates that older patients were at no significant risk of postoperative complications. The CCI/CDG scores may identify patients at higher risk for adverse events after dorsal instrumentation, and these assessments should become an essential component of stratification in this older patient population.

Rapid closure technique in suboccipital decompression.

OBJECTIVE: Suboccipital decompression has been established as standard therapeutic procedure for raised intracranial pressure caused by mass-effect associated pathologies in posterior fossa. Several different surgical techniques of dural closure have been postulated to achieve safe decompression. The aim of this study was to examine the differences between fibrin sealant patch (FSP) and dural reconstruction (DR) in suboccipital decompression for acute mass-effect lesions. METHODS: We retrospectively analyzed our institutional data of patients who underwent suboccipital decompression due to spontaneous intracerebellar hemorrhage, cerebellar infarction and acute traumatic subdural hematoma between 2010 and 2019. Two different dural reconstruction techniques were performed according to the attending neurosurgeon: (1) fibrin sealant patch (FSP), and (2) dural reconstruction (DR) including the use of dural patch. Complications, operative time, functional outcome and the necessity of a ventriculoperitoneal shunt (VP Shunt) were assessed and further analyzed. RESULTS: Overall, 87 patients were treated at the authors' institution (44 in FSP group, 43 in DR group). Glasgow coma scale on admission and preoperative coagulation state did not differ between the groups. Postoperatively, we found no difference in cerebrospinal fluid leakage or chronic hydrocephalus between the groups (p = 0.47). Revision rates were 2.27% (1/44 patients) in the FSP group, compared to 16.27% (7/43) in the DR group (p < 0.023). Operative time was significantly shorter in the FSP group (90.3 ± 31.0 min vs. 199.0 ± 48.8 min, p < 0.0001). CONCLUSION: Rapid closure technique in suboccipital decompression is feasible and safe. Operative time is hereby reduced, without increasing complication rates.

Primary decompressive craniectomy in poor-grade aneurysmal subarachnoid hemorrhage: long-term outcome in a single-center study and systematic review of literature.

Primary decompressive craniectomy (PDC) in patients with poor-grade aneurysmal subarachnoid hemorrhage (aSAH) in order to decrease elevated intracranial pressure (ICP) is controversially discussed. The aim of this study was to analyze the effect of PDC on long-term clinical outcome in these patients in a single-center cohort and to perform a systematic review of literature. Eighty-seven consecutive poor-grade SAH patients (World Federation of Neurosurgical Societies (WFNS) grades IV and V) were analyzed between October 2012 and August 2017 at the author's institution. PDC was performed due to clinical signs of herniation or brain swelling according to the treating surgeon. Outcome was analyzed according to the modified Rankin Scale (mRS). Literature was systematically reviewed up to August 2019, and data of poor-grade aSAH patients who underwent PDC was extracted for statistical analyses. Of 87 patients with poor-grade aSAH in the single-center cohort, 38 underwent PDC and 49 did not. Favorable outcome at 2 years post-hemorrhage did not differ significantly between the two groups (26% versus 20%). Systematic literature review revealed 9 studies: Overall, a favorable outcome could be achieved in nearly half of the patients (49%), with an overall mortality of 24% (median follow-up 11 months). Despite a worse clinical status at presentation (significantly higher rate of mydriasis and additional ICH), poor-grade aSAH patients with PDC achieve favorable outcome in a significant number of patients. Therefore, treatment and PDC should not be omitted in this severely ill patient collective. Prospective controlled studies are warranted.

Initial inflammatory response is an independent predictor of unfavorable outcome in patients with good-grade aneurysmal subarachnoid hemorrhage.

INTRODUCTION: Purpose of the present study was to determine if routine biochemical markers of acute phase response are associated with unfavorable outcome in patients with good-grade aneurysmal SAH. METHODS: 231 patients admitted with aneurysmal SAH and WFNS grade I - II were included in the present study. C-reactive protein (CRP) and procalcitonin (PCT) were measured within 24 h of admission. Outcome was assessed according to the modified Rankin Scale (mRS) after 6 months and stratified into favorable (mRS 0-2) vs. unfavorable (mRS 3-6). RESULTS: The multivariate regression analysis revealed "elevated baseline CRP" (p = .001, OR 3.2, 95% CI 1.6-6.6), "elevated baseline PCT" (p = .004, OR 26.0, 95% CI 2.9-235.5), "male gender" (p = .02, OR 2.3, 95% CI 1.1-4.8), and "age ≥ 65 years" (p = .009, OR 2.7, 95% CI 1.3-5.8) as a model for the prediction of unfavorable outcome in patients with good-grade SAH. CONCLUSION: An initial inflammatory response could be a possible explanation for poor outcome in good-grade SAH patients. These findings might help to identify a subgroup of good grade SAH patients who are at greater risk for unfavorable outcome early during treatment course/at baseline, and who could benefit most from potential anti-inflammatory therapy.

Cavernoma-related epilepsy in cavernous malformations located within the temporal lobe: surgical management and seizure outcome.

OBJECTIVE: Cavernoma-related epilepsy (CRE) is a frequent symptom in patients with cerebral cavernous malformations (CCMs). Reports on surgical management and seizure outcome of epileptogenic CCM often focus on intracranial cavernoma in general. Therefore, data on CCMs within the temporal lobe are scarce. The authors therefore analyzed their institutional data. METHODS: From 2003 to 2018, 52 patients suffering from CCMs located within the temporal lobe underwent surgery for CRE at University Hospital Bonn. Information on patient characteristics, preoperative seizure history, preoperative evaluation, surgical strategies, postoperative complications, and seizure outcome was assessed and further analyzed. Seizure outcome was assessed 12 months after surgery according to the International League Against Epilepsy (ILAE) classification and stratified into favorable (ILAE class I) versus unfavorable (ILAE classes II-VI). RESULTS: Overall, 47 (90%) of 52 patients with CCMs located in the temporal lobe and CRE achieved favorable seizure outcome. Pure lesionectomy was performed in 5 patients, extended lesionectomy with resection of the hemosiderin rim in 38 patients, and anterior temporal lobectomy in 9 patients with temporal lobe CCM. Specifically, 36 patients (69%) suffered from drug-resistant epilepsy (DRE), 3 patients (6%) from chronic CRE, and 13 patients (25%) sustained sporadic CRE. In patients with DRE, favorable seizure outcome was achieved in 32 (89%) of 36 patients. Patients with DRE were significantly older than patients with CCM-associated chronic or sporadic seizures (p = 0.02). Furthermore, patients with DRE more often underwent additional amygdalohippocampectomy following the recommendation of presurgical epileptological evaluation. CONCLUSIONS: Favorable seizure outcome is achievable in a substantial number of patients with epileptogenic CCM located in the temporal lobe, even if patients suffered from drug-resistant CRE. For adequate counseling and monitoring, patients with CRE should undergo a thorough pre- and postsurgical evaluation in dedicated epilepsy surgery programs.

Multiple aneurysms in subarachnoid hemorrhage - identification of the ruptured aneurysm, when the bleeding pattern is not self-explanatory - development of a novel prediction score.

BACKGROUND: In aneurysmal subarachnoid hemorrhage (SAH) and multiple intracranial aneurysms (MIAs) identification of the bleeding source cannot always be assessed according to the hemorrhage pattern. Therefore, we developed a statistical model for the prediction of the ruptured aneurysm in patients with SAH and multiple potential bleeding sources at the time of ictus. METHODS: Between 2012 and 2015, 252 patients harboring 619 aneurysms were admitted to the authors' institution. Patients were followed prospectively. Aneurysm and patient characteristics, as well as radiological findings were entered into a computerized database. Gradient boosting techniques were used to derive the statistical model for the prediction of the ruptured aneurysm. Based on the statistical prediction model, a scoring system was produced for the use in the clinical setting. The aneurysm with the highest score poses the highest possibility of being the bleeding source. The prediction score was then prospectively applied to 34 patients suffering from SAH and harboring MIAs. RESULTS: According to the statistical prediction model the main factors affecting the rupture in patients harboring multiple aneurysms were: 1) aneurysm size, 2) aneurysm location and 3) aneurysm shape. The prediction score identified correctly the ruptured aneurysm in all the patients that were used in the prospective validation. Even in the five most debatable and challenging cases assessed in the period of prospective validation, for which the score was designed for, the ruptured aneurysm was predicted correctly. CONCLUSIONS: This new and simple prediction score might provide additional support for neurovascular teams for treatment decision in SAH patients harboring multiple aneurysms. In a small prospective sample, the prediction score performed with high accuracy but larger cohorts for external validation are warranted.

The impact of the MIB-1 index on facial nerve outcomes in vestibular schwannoma surgery.

BACKGROUND: Facial nerve palsy is a severe morbid condition that occurs after vestibular schwannoma (VS) surgery. The objective of this study was to evaluate facial nerve outcomes based on surgical techniques, tumour size, and immunohistochemical factors. METHODS: One hundred eighteen patients with VS were retrospectively analysed. Gross total resection (GTR) was achieved in 83 patients, and subtotal resection (STR) was achieved in 35 patients. Follow-up was 60 months (median). Facial nerve outcomes were assessed for 24 months after surgery. Analysis of the MIB-1 index was performed in 114 patients (97%) to evaluate recurrence and facial nerve outcomes. RESULTS: Immediately after surgery, 16 of 35 patients (45.7%) with STR and 21 of 83 patients (25.3%) with GTR had a good (House-Brackmann (HB) score ≤ 2) facial nerve outcome (p = 0.029). Semi-sitting positioning (p = 0.002) and tumour size class of 3 (> 4 cm) were also associated with worse HB outcomes after 2 years (p = 0.004) in univariate analyses. The MIB-1 index was significantly correlated with diffuse infiltration of tumour-associated CD45+ lymphocytes (r = 0.63, p = 0.015) and CD68+ macrophages (r = 0.43, p = 0.021). ROC analysis found an AUC of 0.73 (95% CI = 0.60-0.86, p = 0.003) for the MIB-1 index in predicting poor facial nerve outcomes. Binary logistic regression analysis revealed an MIB-1 index ≥ 5% (16/28 (57.1%) vs. 5/40 (12.5%); p < 0.001, OR = 14.0, 95% CI = 3.2-61.1) and a tumour size class of 3 (6/8 (75.0%) vs. 2/8 (25.0%); p = 0.01, OR = 14.56, 95% CI = 1.9-113.4) were predictors of poor HB scores (≥ 3) after 1 year. CONCLUSIONS: An MIB-1 index ≥ 5% seems to predict worse long-term facial nerve outcomes in VS surgery.

Risk of Rebleeding in Patients Suffering From Ruptured Brain Arteriovenous Malformations Undergoing Subacute Treatment: A Single-Center Series and Systematic Review of the Literature.

INTRODUCTION: The optimal timing for treatment of ruptured brain arteriovenous malformation (BAVM) is still controversial. The present study aims to determine safety of subacute BAVM management in clinically stable patients by identifying the rate of rebleeding. METHODS: Patients presenting from 2000 to 2018 with ruptured BAVM who were scheduled for BAVM treatment at least 4 weeks after initial hemorrhage were included in the present study. After neurological rehabilitation of the patient and decreased hemorrhage-induced brain swelling, subacute treatment for the ruptured BAVM was carried out. Primary outcome of the present series was defined as treatment failure resulting from rehemorrhage caused by the ruptured BAVM in patients previously labeled eligible for subacute BAVM treatment. Additionally, we performed a systematic review of the contemporary peer-reviewed literature concerning treatment strategy in patients with ruptured BAVM. RESULTS: Fifty-five patients suffering from ruptured BAVM were considered eligible for subacute BAVM treatment at our institution. No patient suffered from early rebleeding before definitive BAVM treatment in our institutional group. Our own patient data were then pooled with data from the literature, resulting in 166 patients suffering from ruptured BAVM who underwent subacute BAVM treatment. Of these, 1 patient (0.6%) suffered from rehemorrhage during the recovery period 130 days after initial BAVM rupture. CONCLUSIONS: The present series and systematic review revealed a rehemorrhage rate of 0.6% in patients suffering from ruptured BAVM who underwent subacute treatment. Therefore, subacute treatment of patients with ruptured BAVM seems safe after application of rigorous treatment algorithms to sort out patients with higher risk for rehemorrhage.

Risk factors for shunt dependency in patients suffering from spontaneous, non-aneurysmal subarachnoid hemorrhage.

Patients presenting with spontaneous, non-aneurysmal subarachnoid hemorrhage (SAH) achieve better outcomes compared to patients with aneurysmal SAH. Nevertheless, some patients develop shunt-dependent hydrocephalus during treatment course. We therefore analyzed our neurovascular database to identify factors determining shunt dependency after non-aneurysmal SAH. From 2006 to 2016, 131 patients suffering from spontaneous, non-aneurysmal SAH were admitted to our department. Patients were stratified according to the distribution of cisternal blood into patients with perimesencephalic SAH (pSAH) versus non-perimesencephalic SAH (npSAH). Outcome was assessed according to the modified Rankin Scale (mRS) at 6 months and stratified into favorable (mRS 0-2) versus unfavorable (mRS 3-6). A multivariate analysis was performed to identify predictors of shunt dependency in patients suffering from non-aneurysmal SAH. Overall, 18 of 131 patients suffering from non-aneurysmal SAH developed shunt dependency (14%). In detail, patients with npSAH developed significantly more often shunt dependency during treatment course, when compared to patients with pSAH (p = 0.02). Furthermore, patients with acute hydrocephalus, presence of intraventricular hemorrhage, presence of clinical vasospasm, and anticoagulation medication prior SAH developed significantly more often shunt dependency, when compared to patients without (p < 0.0001). However, "acute hydrocephalus" was the only significant and independent predictor for shunt dependency in all patients with non-aneurysmal SAH in the multivariate analysis (p < 0.0001). The present study identified acute hydrocephalus with the necessity of CSF diversion as significant and independent risk factor for the development of shunt dependency during treatment course in patients suffering from non-aneurysmal SAH.

Elevated C-reactive protein and white blood cell count at admission predict functional outcome after non-aneurysmal subarachnoid hemorrhage.

INTRODUCTION: Patients with non-aneurysmal subarachnoid hemorrhage (SAH) are considered to have an overall benign course of disease compared to patients suffering from aneurysmal SAH. Nevertheless, a small but significant number of such patients might only achieve unfavorable outcome. Therefore, the purpose of the present study was to determine if routine laboratory markers of acute phase response are associated with unfavorable outcome in patients with non-aneurysmal SAH. METHODS: From 2006 to 2017, 154 patients suffering from non-aneurysmal SAH were admitted to our institution. Patients were stratified according to the distribution of cisternal blood into patients with perimesencephalic SAH (pSAH) versus non-perimesencephalic SAH (npSAH). C-reactive protein (CRP) and white blood cells (WBC) assessments were performed within 24 h of admission as part of routine laboratory workup. Outcome was assessed according to the modified Rankin Scale (mRS) after 6 months and stratified into favorable (mRS 0-2) vs. unfavorable (mRS 3-6). RESULTS: The multivariate regression analysis revealed "CRP > 5 mg/l" (p = 0.004, OR 143.7), "WBC count > 12.1 G/l" (p = 0.006, OR 47.8), "presence of IVH" (p = 0.02, OR 13.5), "poor-grade SAH" (p = 0.01, OR 45.2) and "presence of CVS" (p = 0.003, OR 149.9) as independently associated with unfavorable outcome in patients with non-aneurysmal SAH. CONCLUSION: Elevated C-reactive protein and WBC count at admission were associated with unfavorable outcome after non-aneurysmal SAH.

Anticoagulation Therapy in Patients Suffering from Aneurysmal Subarachnoid Hemorrhage: Influence on Functional Outcome-a Single-Center Series and Multivariate Analysis.

INTRODUCTION: Favorable outcome in patients presenting with aneurysmal subarachnoid hemorrhage (SAH) is determined by several factors. Nevertheless, data on the influence of prior use of oral anticoagulation drugs on functional outcome in patients suffering from SAH are scarce. We therefore analyzed our institutional data. METHODS: From January 2009 to October 2015, 480 patients suffering from aneurysmal SAH were admitted to our institution. Information including patient characteristics, treatment modality, aneurysm size and location, radiologic features, and functional neurologic outcome was assessed and further analyzed. Outcome was assessed according to the modified Rankin Scale (mRS) at 6 months and stratified into favorable (mRS 0-2) versus unfavorable (mRS 3-6). RESULTS: Overall, 17 of 480 patients suffering from aneurysmal SAH were on anticoagulation therapy before ictus (4%). Patients without anticoagulation therapy were significantly younger compared with patients with anticoagulation therapy before SAH (P = 0.005). Furthermore, patients without anticoagulation therapy presented in a significantly better clinical condition compared with patients with anticoagulation therapy before SAH (P = 0.02). Additionally, patients without anticoagulation therapy achieved significantly more often favorable functional outcome compared with patients with anticoagulation therapy before SAH (P = 0.02). However, anticoagulation therapy was not identified as a significant and independent predictor for unfavorable outcome in the multivariate logistic regression analysis. CONCLUSION: Anticoagulation therapy has not been identified as a significant and independent factor influencing functional outcome in patients suffering from SAH. Therefore treatment should not be omitted. Nevertheless, cautious management is necessary in patients with known anticoagulation therapy before SAH.