Comparison of sex differences on outcomes after aneurysmal subarachnoid hemorrhage: a propensity score-matched analysis.

OBJECTIVE: Sex differences in outcomes of patients with aneurysmal subarachnoid hemorrhage (aSAH) remain controversial. Therefore, the aim of this study was to investigate the sex differences in the prognosis of patients with aSAH. METHODS: This study retrospectively analyzed the clinical data of aSAH patients admitted to the Department of Neurosurgery of General Hospital of Northern Theater Command, from April 2020 to January 2022. The modified Rankin Scale (mRS) was used to evaluate outcomes at 3-month post-discharge. Baseline characteristics, in-hospital complications and outcomes were compared after 1:1 propensity score matching (PSM). RESULTS: A total of 665 patients were included and the majority (63.8%) were female. Female patients were significantly older than male patients (59.3 ± 10.9 years vs. 55.1 ± 10.9 years, P < 0.001). After PSM, 141 male and 141 female patients were compared. Comparing postoperative complications and mRS scores, the incidence of delayed cerebral ischemia (DCI) and hydrocephalus and mRS ≥ 2 at 3-month were significantly higher in female patients than in male patients. After adjustment, the analysis of risk factors for unfavorable prognosis at 3-month showed that age, sex, smoking, high Hunt Hess grade, high mFisher score, DCI, and hydrocephalus were independent risk factors. CONCLUSION: Female patients with aSAH have a worse prognosis than male patients, and this difference may be because females are more vulnerable to DCI and hydrocephalus.

Trends in incidence and treatments of spontaneous subarachnoid hemorrhage- a 10 year hospital based study.

BACKGROUND: Improved endovascular methods make it possible to treat complex ruptured aneurysms, but surgery is still needed in certain cases. We evaluated the effects on the clinical results of the changes in aneurysm treatment. METHODS: The study cohort was 837 patients with spontaneous subarachnoid hemorrhage (SAH) and one or multiple aneurysms, admitted to Dept of Neurosurgery, Uppsala University Hospital from 2012 to 2021. Demography, location and treatment of aneurysms, neurologic condition at admission and discharge, mortality and last tier treatment of high intracranial pressure (ICP) was evaluated. Functional outcome was measured using the Extended Glasgow Outcome Scale (GOSE) Data concerning national incidences of stroke diseases was collected from open Swedish databases. RESULTS: Endovascular methods were used in 666 cases (79.6%). In 111 (13.3%) with stents. Surgery was performed in 115 cases (13.7%) and 56 patients (6.7%) had no aneurysm treatment. The indications for surgery were a hematoma (51 cases, 44.3%), endovascular treatment not considered safe (47 cases, 40.9%), or had been attempted without success (13 cases, 11.3%). Treatment with stent devices increased, and with surgery decreased over time. There was a trend in decrease in hemicraniectomias over time. Both the patient group admitted awake (n = 681) and unconscious (n = 156) improved significantly in consciousness between admission and discharge. Favorable outcome (GOSE 5-8) was seen in 69% for patients admitted in Hunt & Hess I-II and 25% for Hunt & Hess III-V. Mortality at one year was 10.9% and 42.7% for those admitted awake and unconscious, respectively.The number of cases decreased during the study period, which was in line with Swedish national data. CONCLUSIONS: The incidence of patients with SAH gradually decreased in our material, in line with national data. The treatment policy in our unit has been shifting to more use of endovascular methods. During the study period the use of hemicraniectomies decreased.

Health care-associated infections after surgical treatment of ruptured intracranial aneurysms.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (SAH) is catastrophic, and microsurgery for ruptured intracranial aneurysms is one of the preventive modalities for rebleeding. However, patients remain at high risk of medical morbidities after surgery, one of the most important of which is health care-associated infections (HAIs). We analyzed the incidence and risk factors of HAIs, as well as their association with the outcomes after surgical treatment of ruptured aneurysms. METHODS: We retrospectively enrolled 607 patients with SAH who had undergone surgery for intracranial aneurysms. Information was retrieved from the database using codes of the International Classification of Diseases, Ninth Revision, Clinical Modification. RESULTS: Of the 607 patients, 203 were male and 404 were female. HAIs occurred in 113 patients, accounting for 18.6 % of the population. The independent risk factors for HAIs included age ((p = 0.035), hypertension ((p = 0.042), convulsion ((p = 0.023), external ventricular drain ((p = 0.035), ventricular shunt ((p = 0.033), and blood transfusion ((p = 0.001). The mean length of hospital stay was 25.3 ± 18.2 and 18.8 ± 15.3 days for patients with and without HAIs, respectively ((p = 0.001). The in-hospital mortality rates were 11.5 % in the HAIs group, and 14.0 % in the non-HAIs group ((p = 0.490). CONCLUSION: HAIs are a frequent complication in patients with SAH who underwent surgery for ruptured intracranial aneurysms. The length of hospital stay is remarkably longer for patients with HAIs, and to recognize and reduce the modifiable risks should be implemented to improve the quality of patient care.

Coil Embolization of the Azygos Anterior Cerebral Artery Aneurysm: Three Case Reports.

The azygos anterior cerebral artery (ACA) is a rare anatomical anomaly. Clipping surgery has been conducted in approximately 30 reported cases because it is frequently associated with aneurysms. However, few cases in which coil embolization was performed have been reported. We report three cases of coil embolization for distal ACA aneurysms with distal azygos ACA at our institution in 7 years. All patients were over 65-year-old women with saccular aneurysms larger than 7 mm; two with subarachnoid hemorrhage and one with an unruptured aneurysm. No patient had surgical complications associated with coil embolization. Coil embolization is also useful for large aneurysms in the distal azygos ACA, and its indication for treatment could be broadened.

[Subarachnoid hemorrhage in a young girl]. / Een meisje met een subarachnoïdale bloeding.

BACKGROUND: Subarachnoid hemorrhage in children is rare. The most common cause is trauma, followed by an arteriovenous malformation, aneurysm or tumor. CASE DESCRIPTION: We describe the case of an 11-year-old girl who developed sudden headache with nausea and vomiting during athletics training. Her neurological exam was normal. With imaging and a lumbar puncture a subarachnoid hemorrhage was diagnosed, based on a ruptured saccular aneurysm of the right middle cerebral artery. Endovascular treatment was unsuccessful, after which the aneurysm was treated surgically. Postoperative recovery was uneventful. Additional tests for underlying conditions were negative. CONCLUSION: Also in a child with acute headache, nausea, and vomiting, the diagnosis of a subarachnoid hemorrhage should be considered, even if neurological examination is normal. Expeditious diagnosis and treatment are important in order to prevent rebleeding.

[Craniotomy Clipping for Cerebral Aneurysms].

Preoperative simulation is essential to safely complete neurosurgical procedures. A vascular-oriented approach is important in cerebrovascular disorder surgery, considering anatomical variations among individuals. Particularly, subarachnoid hemorrhage surgery requires a detailed simulation of a safe dissection procedure, considering the rupture point of the aneurysm, and combined computed tomography or magnetic resonance imaging images with cerebral angiography can be useful. We present a case of subarachnoid hemorrhage and introduce the preoperative simulation performed at our hospital.

Basilar artery perforator aneurysms: a comparison with non-perforator saccular aneurysms.

BACKGROUND: Basilar artery perforator aneurysms (BAPAs) are rare. There is no systematic description of their presentation, imaging, natural history and outcomes and how these compare to conventional non-perforator aneurysms. Thus, the authors in this study aimed to compare BAPAs to non-perforator aneurysms. METHODS: Cases were identified from a prospective neurovascular database, notes and imaging retrospectively reviewed and compared to a consecutive series of patients with non-perforator aneurysms. Blood volume on CT and vessel wall imaging (VWI) were compared to controls. RESULTS: 9/739 patients with aneurysmal subarachnoid haemorrhage (aSAH) harboured BAPAs. Compared to 103 with aSAH from posterior circulation aneurysms, they were more likely to be male (6/9, p = 0.008), but of equal severity (4/9 poor grade, p = 0.736) and need of CSF drainage (5/9, p = 0.154). Blood volume was similar to controls (30.2 ml vs 26.7 ml, p = 0.716). 6/9 BAPAs were initially missed on CTA. VWI showed thick (2.9 mm ± 2.7) bright enhancement (stalk ratio 1.05 ± 0.12), similar to controls with ruptured aneurysms (0.95 ± 0.23, p = 0.551), and greater than unruptured aneurysms (0.43 ± 0.11, p < 0.001). All were initially managed conservatively. Six thrombosed spontaneously. Three grew and had difficult access with few good endovascular options and were treated through a subtemporal craniotomy without complication. None rebled. At 3 months, all presenting in poor grade were mRS 3-4 and those in good grade mRS 1-2. CONCLUSIONS: Despite their small size, BAPAs present with similar volume SAH, WFNS grade and hydrocephalus to other aneurysms. They are difficult to identify on CTA but enhance strikingly on VWI. The majority thrombosed. Initial conservative management reserving treatment for growth was associated with no rebleeds or complications.

Early Complications and Outcome After Treatment of Ruptured Aneurysms in Patients with Subarachnoid Hemorrhage-A Post Hoc Analysis of the EARLYDRAIN Trial.

OBJECTIVE: Aneurysmal subarachnoid hemorrhage (aSAH) from a ruptured intracranial aneurysm is a severe, life-threatening condition, with high morbidity and mortality. The current treatment often involves surgical clipping or endovascular treatment within the first 24-48 hours. Although there is ample evidence of complications in treating unruptured aneurysms, similar data in patients with acutely ruptured aneurysms are limited. The recently completed EARLYDRAIN trial showed improved neurologic results from lumbar drainage after aneurysm treatment in patients with aSAH. Using this data set, we aim to study the frequency and effects of complications and identify associated risk factors. METHODS: A substudy was carried out of the prospective multicenter randomized controlled EARLYDRAIN trial. We analyzed treatment-associated complications (bleeding and/or infarctions) detected on computed tomography on day 1 after aneurysm occlusion. Outcomes were the occurrence of postprocedural complications, secondary infarctions in the acute phase, and the modified Rankin Scale score after 6 months. RESULTS: The EARLYDRAIN trial recruited 287 patients in 19 centers. Of these patients, 56 (19.5%) experienced a treatment complication. Twenty-five patients (8.7%) experienced postprocedural intracranial hemorrhage and 34 patients (11.8%) experienced a treatment-associated infarction. Patients with a complication showed more secondary infarctions (P = 0.049) and worse neurologic outcomes after 180 days (P = 0.025) compared with patients with no complication. Aneurysm location, rebleeding before the treatment, number of patients recruited per center, and the day of the treatment were independent risk factors for the occurrence of complications. CONCLUSIONS: The present study shows that patients with aSAH frequently experience intervention-associated complications associated with aneurysm occlusion required to prevent recurrent hemorrhage. Consequently, patients with aSAH with treatment-related complications more often experience a worse clinical course and poor outcome.

Ruptured basilar artery perforator aneurysm mimicking superior cerebellar artery aneurysm.

BACKGROUND AND IMPORTANCE: The diagnosis of basilar artery perforator aneurysm is difficult due to their small size, with high rates of negative angiography. Furthermore, due to the considerable variation of basilar artery perforator (BAP), even if an aneurysm originates from a BAP, it is often difficult to clearly identify its origin on angiography. CLINICAL PRESENTATION: A 46-female patient presented with World Federation of Neurological Surgeons Scale 1 subarachnoid hemorrhage. Initial imaging study, including digital subtraction angiography (DSA), revealed no vascular lesions. Two-week after admission, DSA revealed an aneurysm arising from the left superior cerebellar artery (SCA). Endovascular coil embolization was planned first. However, aneurysm selection using microcatheter was failed. Then, surgical approach was done via pre-temporal approach. We identified SCA, but there was no aneurysm. Further dissection revealed an aneurysm arising from basilar artery perforator, which was overlapped by SCA. The parent artery of the aneurysm arose from juxtaproximal to the orifice of left SCA, and crossed SCA at the juxtadistal to the aneurismal sac. Complete clip occlusion was done preserving BAP. After the surgery, the patient developed diplopia without extraoccular movement limitations. Two-month after the surgery, she was fully recovered without any neurologic deficits. CONCLUSION: It is crucial to adequately consider the possibility of open surgery as a viable option in case that endovascular treatment of aneurysms originated from the distal segment of basilar artery proves unsuccessful.

The role of decompressive craniectomy following microsurgical repair of a ruptured aneurysm: Analysis of a South Australian cerebrovascular registry.

OBJECTIVE: Decompressive craniectomy (DC) remains a controversial intervention for intracranial hypertension among patients with aneurysmal subarachnoid haemorrhage (aSAH). METHODS: We identified aSAH patients who underwent DC following microsurgical aneurysm repair from a prospectively maintained registry and compared their outcomes with a propensity-matched cohort who did not. Logistic regression was used to identify predictors of undergoing decompressive surgery and post-operative outcome. Outcomes of interest were inpatient mortality, unfavourable outcome, NIS-Subarachnoid Hemorrhage Outcome Measure and modified Rankin Score (mRS). RESULTS: A total of 246 patients with aSAH underwent clipping of the culprit aneurysm between 01/09/2011 and 20/07/2020. Of these, 46 underwent DC and were included in the final analysis. Unsurprisingly, DC patients had a greater chance of unfavourable outcome (p < 0.001) and higher median mRS (p < 0.001) at final follow-up. Despite this, almost two-thirds (64.1 %) of DC patients had a favourable outcome at this time-point. When compared with a propensity-matched cohort who did not, patients treated with DC fared worse at all endpoints. Multivariable logistic regression revealed that the presence of intracerebral haemorrhage and increased pre-operative mid-line shift were predictive of undergoing DC, and WFNS grade ≥ 4 and a delayed ischaemic neurological deficit requiring endovascular angioplasty were associated with an unfavourable outcome. CONCLUSIONS: Our data suggest that DC can be performed with acceptable rates of morbidity and mortality. Further research is required to determine the superiority, or otherwise, of DC compared with structured medical management of intracranial hypertension in this context, and to identify predictors of requiring decompressive surgery and patient outcome.

Navigated bedside implantation of external ventricular drains with mobile health guidance: technical note and case series.

PURPOSE: External ventricular drain (EVD) implantation is one of the fundamental procedures of emergency neurosurgery usually performed freehand at bedside or in the operating room using anatomical landmarks. However, this technique is frequently associated with malpositioning leading to complications or dysfunction. Here, we describe a novel navigated bedside EVD insertion technique, which is evaluated in a clinical case series with the aim of safety, accuracy, and efficiency in neurosurgical emergency settings. METHODS: From 2021 to 2022, a mobile health-assisted navigation instrument (Thomale Guide, Christoph Miethke, Potsdam, Germany) was used alongside a battery-powered single-use drill (Phasor Health, Houston, USA) for bedside EVD placement in representative neurosurgical pathologies in emergency situations requiring ventricular cerebrospinal fluid (CSF) relief and intracranial pressure (ICP) monitoring. RESULTS: In all 12 patients (8 female and 4 male), navigated bedside EVDs were placed around the foramen of Monro at the first ventriculostomy attempt. The most frequent indication was aneurysmal subarachnoid hemorrhage. Mean operating time was 25.8 ± 15.0 min. None of the EVDs had to be revised due to malpositioning or dysfunction. Two EVDs were converted into a ventriculoperitoneal shunt. Drainage volume was 41.3 ± 37.1 ml per day in mean. Mean length of stay of an EVD was 6.25 ± 2.8 days. Complications included one postoperative subdural hematoma and cerebrospinal fluid infection, respectively. CONCLUSION: Combining a mobile health-assisted navigation instrument with a battery-powered drill and an appropriate ventricular catheter may enable and enhance safety, accuracy, and efficiency in bedside EVD implantation in various pathologies of emergency neurosurgery without adding relevant efforts.

Risk Factors for In-Hospital Seizure and New-Onset Epilepsy in Coiling and Clipping Treatment of Aneurysmal Subarachnoid Hemorrhage.

OBJECTIVE: To identify risk factors associated with in-hospital seizures and new-onset epilepsy in patients with aneurysmal subarachnoid hemorrhage (SAH) who underwent coiling embolization or clipping surgery. METHODS: This retrospective descriptive study included 195 patients diagnosed with aneurysmal SAH and treated with coiling embolization or clipping surgery between January 2018 and June 2022. RESULTS: Among the 195 patients meeting inclusion criteria, 9 experienced an onset seizure at the time of SAH. In-hospital seizures were observed in 33 patients, of which 24 were electrographic seizures detected in 24 patients with suspected subclinical seizures. After 12 months of follow-up, 11 patients met criteria for diagnosis of epilepsy. The incidence of epilepsy after discharge at 12 months was 2.41% in the coiling group and 8.03% in the clipping group. The risk of in-hospital seizures was significantly higher in the clipping group (P = 0.007), although the difference was not statistically significant after 12 months of follow-up (P = 0.121). CONCLUSIONS: Epilepsy following aneurysmal SAH was relatively common. Clipping surgery and brain edema emerged as independent predictive factors for in-hospital seizures, while onset seizures and in-hospital seizures were identified as independent predictors of epilepsy during follow-up. Patients presenting with these risk factors may benefit from long-term electroencephalogram monitoring and should be considered for prophylactic antiepileptic drugs. Additionally, lumbar drainage proved effective in improving both early and late epileptic outcomes in the group with Fisher grades 3 and 4.

Isolated spinal artery aneurysm: etiology, clinical characteristics, and outcomes.

OBJECTIVE: Isolated spinal aneurysms (ISAs) are rare causes of subarachnoid hemorrhage (SAH), which encompass a highly heterogeneous group of clinical entities with multifarious pathogeneses, clinical characteristics, and treatment strategies. Therefore, knowledge about the ISAs remains inadequate. In this study, the authors present a comprehensive analysis of clinical data associated with ISAs at their institutions to enhance the understanding of this disease. METHODS: Patients with ISAs confirmed by spinal angiography or surgery at the authors' institutions between 2015 and 2022 were included. Data regarding clinical presentation, lesion location, aneurysm morphology, comorbidities, treatment results, and clinical outcomes were reviewed. RESULTS: Seven patients with ISAs were included in the study. Among them, 4 patients (57.1%) experienced severe headache, and 3 patients (42.9%) reported sudden-onset back pain. Additionally, lower-extremity weakness and urinary retention were observed in 2 of these patients (28.6%). Four of the aneurysms exhibited fusiform morphology, whereas the remaining were saccular. All saccular aneurysms in this series were attributed to hemodynamic factors. Conservative treatment was administered to 3 patients, 2 of whom underwent follow-up digital subtraction angiography, which showed spontaneous occlusion of both aneurysms. Four patients ultimately underwent invasive treatments, including 2 who underwent microsurgery and 2 who received endovascular embolization. One patient died of recurrent SAH, while the remaining 6 patients had a favorable prognosis at the latest follow-up assessment. CONCLUSIONS: The morphology of aneurysms may be associated with their etiology. Saccular ISAs are usually caused by pressure due to abnormally increased blood flow, whereas fusiform lesions may be more likely to be secondary to vessel wall damage. The authors found that a saccular spinal aneurysm in young patients with a significant dilated parent artery may be a vestige of spinal cord arteriovenous shunts. ISAs can be managed by surgical, endovascular, or conservative procedures, and the clinical outcome is generally favorable. However, the heterogeneous nature of the disease necessitates personalized treatment decision-making based on specific clinical features of each patient.

[Russian study on brain aneurysm surgery: a continuation (RIHA II)]. / Rossiiskoe issledovanie po khirurgii anevrizm golovnogo mozga: prodolzhenie (RIKhA II).

OBJECTIVE: To assess the main performance indicators of neurosurgical departments in surgical treatment of cerebral aneurysms in the Russian Federation. MATERIAL AND METHODS: We analyzed 22 neurosurgical departments (19 regional and 3 federal hospitals) in 2017 and 2021. The study enrolled 6.135 patients including 3.160 ones in 2017 and 2.975 ones in 2021. We studied the features of surgical treatment of cerebral aneurysms in different volume hospitals and factors influencing postoperative outcomes. RESULTS: The number of surgeries for cerebral aneurysms decreased from 2.950 in 2017 to 2.711 in 2021. Postoperative mortality rate was 6.3% and 5.6%, respectively. The number of microsurgical interventions decreased from 60% in 2017 to 48% in 2021. The share of endovascular interventions increased from 40% to 52%, respectively. Endovascular embolization was accompanied by stenting in 55% of cases. Simultaneous revascularization was carried out in 2% of cases. In 2021, the number of patients undergoing surgery in acute period of hemorrhage increased to 70% (in 2017 - 61%). The number of hospitals performing more than 50 surgical interventions for cerebral aneurysms annually increased from 14 in 2017 to 17 in 2021. CONCLUSION: Certain changes in neurosurgical service occurred in 2021 compared to 2017. Lower number of surgical interventions for cerebral aneurysms, most likely caused by the COVID-19 pandemic, is accompanied by lower postoperative mortality. Endovascular interventions and revascularization techniques became more common. The number of surgeries in acute period after aneurysm rupture and hospitals performing more than 50 surgical interventions for cerebral aneurysms annually increased.

Factors Associated with Early and Late Seizure Related to Aneurysmal Subarachnoid Hemorrhage.

Post-stroke epilepsy may occur after aneurysmal subarachnoid hemorrhage (aSAH). Both early and late seizures could cause severe neurocognitive deficits if administration of appropriate antiseizure medication is delayed. Therefore, it is important to elucidate the risk factors for early and late seizures, which could be shared with medical teams to promptly manage seizures. There are aspects of both hemorrhage and ischemia in aSAH, and thus, numerous risk factors are considered for early and late seizures. We examined factors associated with aSAH-related early and late seizures. Among 297 patients who had aSAH and underwent direct or endovascular surgery, 25 had early seizures and 20 had late seizures. Patients who did not experience any seizures in at least 2-years of follow-up (n = 81) were used as the control group. Early seizures were associated with older age and acute severe nonneurological infection, whereas late seizures were associated with intraparenchymal lesion volume >10 mL and shunt placement. In patients with late seizures, consistency was frequently observed between electroencephalogram and the presence of intraparenchymal lesions. The frontopolar electrode on electroencephalogram was highly sensitive to abnormality in early seizures. Early seizures were induced by the patient's systemic factors, which may lower the threshold for cortical excitability. Patients with intraparenchymal lesions who undergo shunt placement should be carefully followed up for late seizures.

Microsurgical Clipping after Failed Contour Device Embolization of an Anterior Communicating Artery Aneurysm: Technical Note.

BACKGROUND: Endovascular therapy has revolutionized the treatment of cerebral aneurysms in recent years and decades. So-called intrasaccular devices (i.e., Woven EndoBridge [WEB], MicroVention, Aliso Viejo, California, United States; or Contour, Cerus Neurovascular, Fremont, California, United States) are a promising endovascular technology, especially for wide-based aneurysms. However, long-term outcome data are currently particularly scarce for Contour and strategies for failed Contour cases are lacking. Here, we report the feasibility of microsurgical clipping after failed Contour device embolization. METHODS: Feasibility of microsurgical clipping after failed aneurysm embolization with a Contour intrasaccular device was assessed in a patient. RESULTS: We present the case of a 36-year-old male patient diagnosed with Hunt and Hess grade 1 subarachnoid hemorrhage from an anterior communicating artery aneurysm. The ruptured aneurysm was initially treated with the Contour device. After 3 months, angiographic imaging showed a clear aneurysm residual deemed not endovascularly accessible. The patient was then successfully clipped using microsurgical techniques. The patient was discharged with no neurologic abnormalities. CONCLUSION: After thorough bibliographical research, this presents the first published case report of microsurgical clipping after failed embolization with Contour. The main insights gained after clipping were that the Contour does not significantly disturb or hinder clipping. In contrast to coils in aneurysms to be clipped, the Contour can be easily compressed by the clip blades and does not have to be removed. In addition, the Contour had not migrated into the subarachnoid space and there was no abnormal scarring. Clipping appears to be a reasonable treatment strategy for failure of embolization with Contour if endovascular means are not suitable.

A Step-by-Step Dissection of Cerebral Pathologies for Neurosurgical Trainees: The Middle Cerebral Artery Bifurcation Aneurysm.

BACKGROUND: Aneurysmal subarachnoid hemorrhage remains one of the most prevalent causes of strokes in the young causing a high socioeconomic damage. Both emergent and elective treatments of intracranial aneurysms remain essential challenges for neurovascular centers. We aim to present conceptual education on clip ligation of middle cerebral artery bifurcation aneurysms in an accessible and structured way to maximize the educational takeaway of residents from aneurysm cases. METHODS: After 30 years of experience of the senior author in cerebrovascular surgery in three centers, we closely reviewed an exemplary case of elective right middle cerebral artery bifurcation aneurysm clipping and contrasted it to an alternative microneurosurgical approach to illustrate key principles of microneurosurgical clip ligation for neurosurgical trainees. RESULTS: Dissection of the sylvian fissure, subfrontal approach to the optic-carotid complex, proximal control, aneurysm dissection, dissection of kissing branches, dissection of aneurysm fundus, temporary and permanent clipping, as well as aneurysm inspection and resection are highlighted as key steps of clip ligation. This proximal-to-distal approach is contrasted to the distal-to-proximal approach. Additionally, general principles of intracranial surgery such as use of retraction, arachnoid dissection, and draining of cerebrospinal fluid are addressed. CONCLUSION: Due to a constantly decreasing case load in the era of neurointerventionalism, the paradox of facing increased complexity with decreased experience must be met with a sophisticated practical and theoretical education of neurosurgical trainees early on and with a low threshold.

A Global Review of the Perioperative Care of Patients With Aneurysmal Subarachnoid Hemorrhage Undergoing Microsurgical Repair of Ruptured Intracerebral Aneurysm.

INTRODUCTION: To describe the perioperative care of patients with aneurysmal subarachnoid hemorrhage (aSAH) who undergo microsurgical repair of a ruptured intracerebral aneurysm. METHODS: An English language survey examined 138 areas of the perioperative care of patients with aSAH. Reported practices were categorized as those reported by <20%, 21% to 40%, 41% to 60%, 61% to 80%, and 81% to 100% of participating hospitals. Data were stratified by Worldbank country income level (high-income or low/middle-income). Variation between country-income groups and between countries was presented as an intracluster correlation coefficient (ICC) and 95% confidence interval (CI). RESULTS: Forty-eight hospitals representing 14 countries participated in the survey (response rate 64%); 33 (69%) hospitals admitted ≥60 aSAH patients per year. Clinical practices reported by 81 to 100% of the hospitals included placement of an arterial catheter, preinduction blood type/cross match, use of neuromuscular blockade during induction of general anesthesia, delivering 6 to 8 mL/kg tidal volume, and checking hemoglobin and electrolyte panels. Reported use of intraoperative neurophysiological monitoring was 25% (41% in high-income and 10% in low/middle-income countries), with variation between Worldbank country-income group (ICC 0.15, 95% CI 0.02-2.76) and between countries (ICC 0.44, 95% CI 0.00-0.68). The use of induced hypothermia for neuroprotection was low (2%). Before aneurysm securement, variable in blood pressure targets was reported; systolic blood pressure 90 to 120 mm Hg (30%), 90 to 140 mm Hg (21%), and 90 to 160 mmHg (5%). Induced hypertension during temporary clipping was reported by 37% of hospitals (37% each in high and low/middle-income countries). CONCLUSIONS: This global survey identifies differences in reported practices during the perioperative management of patients with aSAH.