Hematocrit drift and outcomes in surgical patients with aneurysmal subarachnoid hemorrhage.

BACKGROUND: There is a paucity of conclusive evidence regarding the impact of downward drift in hematocrit levels among patients who have undergone surgical clipping for aneurysmal subarachnoid hemorrhage (aSAH). This study endeavors to explore the potential association between hematocrit drift and mortality in this specific patient population. METHODS: A cohort study was conducted, encompassing adult patients diagnosed with aSAH at a university hospital. The primary endpoint was follow-up mortality. Propensity score matching was employed to align patients based on their baseline characteristics. Discrimination capacity across various models was assessed and compared using net reclassification improvement (NRI). RESULTS: Among the 671 patients with aSAH in the study period, 118 patients (17.6%) experienced an in-hospital hematocrit drift of more than 25%. Following adjustment with multivariate regression analysis, patients with elevated hematocrit drift demonstrated significantly increased odds of mortality (aOR: 2.12, 95% CI: 1.14 to 3.97; P = 0.019). Matching analysis yielded similar results (aOR: 2.07, 95% CI: 1.05 to 4.10; P = 0.036). The inclusion of hematocrit drift significantly improved the NRI (P < 0.0001) for mortality prediction. When in-hospital hematocrit drift was served as a continuous variable, each 10% increase in hematocrit drift corresponded to an adjusted odds ratio of 1.31 (95% CI 1.08-1.61; P = 0.008) for mortality. CONCLUSIONS: In conclusion, the findings from this comprehensive cohort study indicate that a downward hematocrit drift exceeding 25% independently predicts mortality in surgical patients with aSAH. These findings underscore the significance of monitoring hematocrit and managing anemia in this patient population.

QTc prolongation after aneurysmal subarachnoid hemorrhage might be associated with worse neurologic outcome in patients receiving microsurgical clipping or embolization of the intracranial aneurysms: a retrospective observational study.

PURPOSE: QT interval prolongation is one of the most common electrocardiographic (ECG) abnormalities in patients with aneurysmal subarachnoid hemorrhage (aSAH). Whether corrected QT interval (QTc) prolongation is associated with perioperative cardiac events and dismal neurological outcome in mid to long-term follow-up in patients after aSAH is insufficiently studied and remains controversial. METHODS: We retrospectively studied the adult (≥ 18 years) patients admitted to our institution between Jan 2018 and Dec 2020 for aSAH who underwent intracranial aneurysm clipping or embolization. The patients were divided into 2 groups (normal and QTc prolongation groups) according to their QTc. To minimize the confounding bias, a propensity score matching (PSM) analysis was performed to compare the neurologic outcomes between patients with normal QTc and QTc prolongation. RESULTS: After screening, 908 patients were finally included. The patients were divided into 2 groups: normal QTc groups (n = 714) and long QTc group (n = 194). Female sex, hypokalemia, posterior circulation aneurysm, and higher Hunt-Hess grade were associated with QTc prolongation. In multiple regression analysis, older age, higher hemoglobin level, posterior circulation aneurysm, and higher Hunt-Hess grade were identified to be associated with worse outcome during 1-year follow-up. Before PSM, patients with QTc prolongation had higher rate of perioperative cardiac arrest or ventricular arrhythmias. After PSM, there was no statistical difference between normal and QTc prolongation groups in perioperative cardiac events. However, patients in the QTc prolongation group still had worse neurologic outcome during 1-year follow-up. CONCLUSIONS: QTc prolongation is associated with worse outcome in patients following SAH, which is independent of perioperative cardiac events.

Risk factors for cerebral edema following aneurysm clipping in patients with aneurysmal subarachnoid hemorrhage.

OBJECTIVES: To investigate the factors that contribute to the development of cerebral edema after aneurysm clipping in individuals with aneurysmal subarachnoid hemorrhage (aSAH). METHODS: A total of 232 patients with aSAH caused by rupture and treated with aneurysm clipping were included in the retrospective analysis of clinical data. Postoperatively, the participants were categorized into two groups based on the presence or absence of cerebral edema: a complication group (n=33) and a non-complication group (n=199).A comparison was made between the overall data of the 2 groups. RESULTS: In the complication group, there were higher proportions of patients experiencing recurrent bleeding, aneurysm in the posterior circulation, Fisher grade III-IV, World Federation of Neurosurgical Societies (WFNS) grade II, Hunt-Hess grade III-IV, concomitant hypertension, duration from onset to operation ≥12 h, and concomitant hematoma compared to the non-complication group (p<0.05). Cerebral edema after aneurysm clipping was associated with several risk factors including repeated bleeding, aneurysm in the back of the brain, Fisher grade III-IV, WFNS grade II, Hunt-Hess grade III-IV, simultaneous high blood pressure and hematoma, and a duration of at least 12 hours from the start of symptoms to the surgical procedure (p<0.05). CONCLUSION: In patients with aSAH, the risk of cerebral edema after aneurysm clipping is increased by recurrent bleeding, aneurysm in the posterior circulation, Fisher grade III-IV, WFNS grade II, Hunt-Hess grade III-IV, concomitant hypertension and hematoma, and duration of ≥12 h from onset to operation.

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.

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.

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.

One-year survival of aneurysmal subarachnoid hemorrhage after airplane transatlantic transfer - a monocenter retrospective study.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) is preferentially treated by prompt endovascular coiling, which is not available in Guadeloupe. Subsequently, patients are transferred to Paris, France mainland, by commercial airplane (6751 km flight) after being managed according to guidelines. This study describes the characteristics, management and outcomes related to these patients. METHODS: Retrospective observational cohort study of 148 patients admitted in intensive care unit for a suspected aSAH and transferred by airplane over a 10-year period (2010-2019). RESULTS: The median [interquartile range] age was 53 [45-64] years and 61% were female. On admission, Glasgow coma scale was 15 [13-15], World Federation of Neurological Surgeons (WFNS) grading scale was 1 [1-3] and Fisher scale was 4 [2-4]. External ventricular drainage and mechanical ventilation were performed prior to the flight respectively in 42% and 47% of patients. One-year mortality was 16% over the study period. By COX logistic regression analysis, acute hydrocephalus (hazard ratio [HR] 2.34, 95% confidence interval [CI] 0.98-5.58) prior to airplane transfer, WFNS grading scale on admission (HR 1.53, 95% CI 1.16-2.02) and age (OR 1.03, 95% 1.00-1.07) were associated with one-year mortality. CONCLUSION: When necessary, transatlantic air transfer of patients with suspected aSAH after management according to local guidelines seems feasible and safe.

Cytotoxic Lesions of the Corpus Callosum Associated with Aneurysmal Subarachnoid Hemorrhage May Influence Shunt-Dependent Chronic Hydrocephalus.

BACKGROUND: Cytotoxic lesions of the corpus callosum (CLOCCs) are occasionally associated with aneurysmal subarachnoid hemorrhage (aSAH). The effects of aSAH on clinical outcomes in such cases are unclear. The present study aimed to investigate the frequency and characteristics of CLOCCs associated with aSAH to ascertain the predictors of shunt-dependent chronic hydrocephalus (SDCH) after aSAH. METHODS: We retrospectively investigated cases of aSAH treated by coil embolization. Patients were divided into those with and without CLOCCs. Between-group differences were evaluated, including clinical outcomes and the characteristics of both the patients and the aneurysms. Patients were divided into those with and without SDCH to identify predictive factors of SDCH after aSAH focusing on CLOCCs. RESULTS: This single-center study included 196 patients with aSAH. All patients received coil embolization between April 2013 and March 2020. CLOCCs were detected in 38 (19.4%) patients. In the group with CLOCCs, male sex, poor severity grade at onset, acute hydrocephalus, SDCH (all P < 0.01), and Fisher group 3 or 4 (P = 0.04) were significantly more common than in the group without CLOCCs. Diabetes and CLOCCs were significant predictors of SDCH after aSAH in multivariate analysis (diabetes: P < 0.01, odds ratio: 6.73, 95% confidence interval: 1.61-28.09; CLOCCs: P < 0.01, odds ratio: 6.86, 95% confidence interval: 2.87-16.38). CONCLUSIONS: CLOCCs and SDCH were common in patients with poor-grade aSAH, and CLOCCs were independent predictors of SDCH after aSAH. Meticulous follow-up is necessary to detect SDCH after aSAH, especially in patients with poor-grade aSAH and CLOCCs.

Comparison of efficacy between clazosentan and fasudil hydrochloride-based management of vasospasm after subarachnoid hemorrhage focusing on older and WFNS grade V patients: a single-center experience in Japan.

Subarachnoid hemorrhage often leads to poor outcomes owing to vasospasm, even after successful aneurysm treatment. Clazosentan, an endothelin receptor inhibitor, has been proven to be an effective treatment for vasospasms in a Japanese randomized controlled trial. However, its efficacy in older patients (≥ 75 years old) and those with World Federation of Neurosurgical Societies (WFNS) grade V has not been demonstrated. We retrospectively evaluated the efficacy of clazosentan in older patients and those with WFNS grade V, using real-world data. Patients with subarachnoid hemorrhage treated before and after the introduction of clazosentan were retrospectively evaluated. The patients were categorized into two groups (clazosentan era versus pre-clazosentan era), in which vasospasm management and outcomes were compared. Vasospasms were managed with fasudil hydrochloride-based (pre-clazosentan era) or clazosentan-based treatment (clazosentan era). Seventy-eight patients were included in this study: the clazosentan era (n = 32) and pre-clazosentan era (n = 46). Overall, clazosentan significantly reduced clinical vasospasms (clazosentan era: 31.3% versus pre-clazosentan era: 60.9%, p = 0.01), delayed cerebral ischemia (DCI) (9.4% versus 39.1%, p = 0.004), and vasospasm-related morbidity and mortality (M/M) (3.1% versus 19.6%, p = 0.03). In subgroup analysis of older patients or those with WFNS grade V, no significant difference was observed in clinical outcomes, although both DCI and vasospasm-related M/M were lower in the clazosentan era. Clazosentan was more effective than fasudil-based management in preventing DCI and reducing vasospasm-related M/M. Clazosentan could be used safely in older patients and those with WFNS grade V, although clinical outcomes in these patients were comparable to those of conventional treatment.

[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.

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.

[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.

Hemorrhage Volume Drives Early Brain Injury and Outcome in Poor-Grade Aneurysmal SAH.

BACKGROUND AND PURPOSE: Early brain injury is a major determinant of clinical outcome in poor-grade (World Federation of Neurosurgical Societies [WFNS] IV-V) aneurysmal SAH and is radiologically defined by global cerebral edema. Little is known, though, about the effect of global intracranial hemorrhage volume on early brain injury development and clinical outcome. MATERIALS AND METHODS: Data from the multicentric prospective Poor-Grade Aneurysmal Subarachnoid Hemorrhage (POGASH) Registry of consecutive patients with poor-grade aneurysmal SAH admitted from January 1, 2015, to August 31, 2022, was retrospectively evaluated. Poor grade was defined according to the worst-pretreatment WFNS grade. Global intracranial hemorrhage volume as well as the volumes of intracerebral hemorrhage, intraventricular hemorrhage, and SAH were calculated by means of analytic software in a semiautomated setting. Outcomes included severe global cerebral edema (defined by Subarachnoid Hemorrhage Early Brain Edema Score grades 3-4), in-hospital mortality (mRS 6), and functional independence (mRS 0-2) at follow-up. RESULTS: Among 400 patients (median global intracranial hemorrhage volume of 91 mL; interquartile range, 59-128), severe global cerebral edema was detected in 218/400 (54.5%) patients. One hundred twenty-three (30.8%) patients died during the acute phase of hospitalization. One hundred fifty-five (38.8%) patients achieved mRS 0-2 at a median of 13 (interquartile range, 3-26) months of follow-up. Multivariable analyses showed global intracranial hemorrhage volume as independently associated with severe global cerebral edema (adjusted OR, 1.009; 95% CI, 1.004-1.014; P < .001), mortality (adjusted OR, 1.006; 95% CI, 1.001-1.01; P = .018) and worse clinical outcome (adjusted OR, 0.992; 95% CI, 0.98-0.996; P < .010). The effect of global intracranial hemorrhage volume on clinical-radiologic outcomes changed significantly according to different age groups (younger than 50, 50-70, older than 70 year of age). Volumes of intracerebral hemorrhage, intraventricular hemorrhage, and SAH affected the 3 predefined outcomes differently. Intracerebral hemorrhage volume independently predicted global cerebral edema and long-term outcome, intraventricular hemorrhage volume predicted mortality and long-term outcome, and SAH volume predicted long-term clinical outcome. CONCLUSIONS: Global intracranial hemorrhage volume plays a pivotal role in global cerebral edema development and emerged as an independent predictor of both mortality and long-term clinical outcome. Aging emerged as a reducing predictor in the relationship between global intracranial hemorrhage volume and global cerebral edema.

Effect of Peri-operative Blood Transfusion on Neurological Outcome Following Aneurysmal Subarachnoid Hemorrhage: A Prospective Observational Study.

BACKGROUND: Anemia is a common complication of aneurysmal subarachnoid hemorrhage and is associated with unfavorable outcomes. Whether the physiological benefits of transfusion for anemia surpass the risk of blood transfusion remains to be determined. OBJECTIVES: The primary outcome was to evaluate the impact of peri-operative blood transfusion on the long-term neurological outcome, assessed by Glasgow Outcome Scale Extended at 3 months. The secondary outcomes included the impact of transfusion on the short-term neurological outcome, assessed by Modified Rankin Score at discharge/7 days, and on the incidence of vasospasm, infarction, re-exploration, tracheostomy, and length of hospital stay. MATERIAL AND METHODS: This prospective observational study was conducted on 185 patients with aneurysmal subarachnoid hemorrhage undergoing clipping of the aneurysmal neck. In our study, blood transfusion was administered to keep the target Hb around 10 g/dL. RESULTS: Unfavorable long-term outcome was found in 27/97 (28%) of patients who received a blood transfusion as compared to 13/74 (18%) of patients who did not receive a transfusion (P = 0.116). Patients receiving transfusion had more chances of an unfavorable outcome at discharge/7 days as compared to those not transfused [44/103 (43%) versus 22/80 (27%)], P = 0.025. There were increased chances of vasospasm, infarction, re-exploration, tracheostomy, and increased length of hospital stay in patients receiving transfusion (P < 0.05). CONCLUSIONS: The use of blood transfusion in patients with aneurysmal subarachnoid hemorrhage was associated with increased neurological complications and hence an unfavorable short-term outcome. However, when used judiciously as per the clinical requirements, blood transfusion did not have a significant effect on long-term neurological outcome.

Microsurgical Clip Reconstruction of a True Posterior Communicating Artery Aneurysm.

Approximately 25% of intracranial aneurysms originate at the internal carotid artery and posterior communicating artery (PCoA) junction.1 In contrast to typical PCoA aneurysms, which are usually saccular, a subset known as true PCoA aneurysms arise directly from the PCoA. These represent about 1.3% of all intracranial aneurysms and 6.8% of PCoA aneurysms.1 The first report of a true PCoA aneurysm was in 1979.2Video 1 illustrates the microsurgical clipping of a true PCoA aneurysm in a 27-year-old man with subarachnoid hemorrhage and left-sided ophthalmoplegia. Computed tomography angiography revealed a large true patient consent, Our surgical strategy included 1) an extended pterional approach, 2) early brain relaxation through basal cisterns and third ventricle opening, 3) Sylvian fissure dissection, 4) partial uncus resection, 5) tracing the PCoA to the aneurysm, 6) pilot clipping and thrombectomy, and 7) careful aneurysm dissection and definitive clipping. The patient had an uncomplicated recovery and was discharged on postoperative day 5 with resolved third nerve dysfunction. A literature review from 2022 documented only 47 cases of true PCoA aneurysms, predominantly manifesting with rupture.3 Some studies suggest that these aneurysms may have a higher rupture risk than typical internal carotid artery-PCoA junction aneurysms.4 Microsurgical clipping is a primary treatment, often in cases associated with a fetal posterior cerebral artery variant.5 Ensuring the patency of the PCoA and thalamoperforating arteries is crucial, with careful visualization of the clip's distal ends to avoid impacting nearby neurovascular structures.

Pediatric Donut-Shaped Basilar Artery Aneurysm.

Intracranial aneurysms are uncommon in the pediatric population. We present a case of an 11-year-old boy presenting with subarachnoid hemorrhage caused by a "donut-shaped" basilar tip aneurysm. It occurs when the flow geometry produces a circumferential laminar flow into the aneurysmal sac, resulting in a central thrombosis. Optimal management of this type of aneurysm is not already clear, and further studies are needed to clarify the best treatment approach, especially in the pediatric population.

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.