Nonaneurysmal Subarachnoid Hemorrhage Research Articles

Evaluating Deep Learning Techniques for Detecting Aneurysmal Subarachnoid Hemorrhage: A Comparative Analysis of Convolutional Neural Network and Transfer Learning Models

Machine learning (ML) and deep learning (DL) techniques offer a promising multidisciplinary solution for subarachnoid hemorrhage (SAH) detection. The novel transfer learning approach mitigates the time constraints associated with the traditional techniques and demonstrates a superior performance. This study aims to evaluate the effectiveness of convolutional neural networks (CNNs) and CNN-based transfer learning models in differentiating between aneurysmal subarachnoid hemorrhage (aSAH) and nonaneurysmal subarachnoid hemorrhage (naSAH). Data from Istanbul Ümraniye Training and Research Hospital, which included 15,600 DICOM images from 123 patients with aSAH and 7,793 images from 80 patients with naSAH, were used. The study employed four models: Inception-V3, EfficientNetB4, single-layer CNN, and three-layer CNN. Transfer learning models were customized by modifying the last three layers and using the Adam optimizer. The models were trained on Google Collaboratory and evaluated based on metrics such as F-score, precision, recall, and accuracy. EfficientNetB4 demonstrated the highest accuracy (99.92%), with a better F-score (99.82%), recall (99.92%), and precision (99.90%) than the other methods. The single- and three-layer CNNs and the transfer learning models produced comparable results. No overfitting was observed, and robust models were developed. CNN-based transfer learning models can accurately diagnose the etiology of SAH from CT images and is a valuable tool for clinicians. This approach could reduce the need for invasive procedures such as digital subtraction angiography, leading to more efficient medical resource utilization and improved patient outcomes.

The value of modified hijdra score in patients with aneurysmal subarachnoid hemorrhage

BackgroundThe complexity of calculating the Hijdra score has limited its clinical utility in aiding the diagnosis of intracranial ruptured aneurysms. ObjectiveThis study aimed to investigate the diagnostic and prognostic value of the modified Hijdra score in patients with aneurysmal subarachnoid hemorrhage (aSAH). MethodsData from 773 patients with subarachnoid hemorrhage (SAH) at the First People's Hospital of Lianyungang from January 2018 to June 2023 were collected. The modified Hijdra scoring method simplifies the assessment of 10 basal cisterns/cisterns fissures compared to the traditional scoring method, with scores ranging from 0 to 2 for each item, and assigns specific scores to hematomas larger than 1 cm in diameter. The data were divided into an evaluation group (n = 641) and a validation group (n = 132). In the evaluation group, the performance of the modified Hijdra score in diagnosis and prognostic prediction was assessed, while the diagnostic and prognostic prediction efficacy of the modified Hijdra method was evaluated using the validation set. ResultsAmong the 641 patients in the evaluation group,550 (85. 8%) were diagnosed with intracranial aneurysms. The modified Hijdra score demonstrated an AUC of 0. 894 for aneurysm diagnosis, with a sensitivity of 98. 0% and a specificity of 64. 8% at a CutOff value of 7. 5. The diagnostic efficacy of the modified Hijdra score was 93. 24%, with a negative predictive value of 84. 29%, while the Hijdra score 's diagnostic efficacy was 85. 34% with a negative predictive value of 48. 89%. The AUC of the modified Hijdra score for predicting prognosis in patients with aneurysms was 0. 824, with a sensitivity of 84. 3% and a specificity of 70. 0% at a CutOff value of 16. 5. In CTA-negative patients, the modified Hijdra score was significantly higher (P < 0. 0001) in patients with aneurysmal SAH (15. 48 ± 3. 93) compared to those with non-aneurysmal SAH (6. 31 ± 4. 52). ConclusionsThe modified Hijdra score is a valuable tool for assisting in the diagnosis and prognosis prediction of aneurysmal subarachnoid hemorrhage.

Aneurysmal Versus “Benign” Perimesencephalic Subarachnoid Hemorrhage

Background The rate of underlying ruptured aneurysms, complications, and their relevance to outcomes in “benign” perimesencephalic subarachnoid hemorrhage are not well known and underreported. Methods Retrospective analysis of patients with perimesencephalic subarachnoid hemorrhage from a large tertiary care center (2007–2022). Results Eighty‐one patients were included with mean age of 55.5 ± 10.3 years. An underlying ruptured aneurysm was diagnosed in 5 patients (6.2%); 3 (60%) had negative computed tomography angiography and they were detected only in digital subtraction angiography (2 on initial digital subtraction angiography and 1 on follow‐up digital subtraction angiography). The most common complication was vasospasm in 25/81 patients (31%), and the majority 21/25 (84%) were asymptomatic. Symptomatic vasospasm occurred at a significantly higher rate among patients with underlying aneurysm (40% versus 2.6%; P = 0.01). Hydrocephalus occurred in 10% of patients, all within 1 day, but at a higher rate in the aneurysmal group (40% versus 8%; P = 0.07). A total of 88% of patients had modified Rankin scale score 0–2 at discharge, but at a significantly higher rate in nonaneurysmal patients (91% versus 40%; P = 0.01). An underlying aneurysm, hydrocephalus, and symptomatic vasospasm were associated with poor functional status (odds ratio [OR] = 14.7 [2.1–104]; P = 0.007, OR = 22.6 [4.2–123.5]; P &lt;0.001, OR = 8.6 [1.06–69.88]; P = 0.04), respectively. Conclusion “Benign” perimesencephalic subarachnoid hemorrhage pattern was associated with a ruptured aneurysm in 6.2% of patients, and 3.7% were detected only on cerebral angiogram. Underlying aneurysm, symptomatic vasospasm, and hydrocephalus were associated with lower rates of good clinical outcome. All hydrocephalus cases were symptomatic and occurred very early. Asymptomatic vasospasm alone was not associated with poor outcomes. Our findings suggest that patients with nonaneurysmal perimesencephalic subarachnoid hemorrhage without hydrocephalus can safely be managed with less strict monitoring and a shorter hospital stay.

Abstract TP1: Changing Trends in the Epidemiology of Subarachnoid Hemorrhage: A Population-Based Study

Background: There are conflicting data on temporal trends in subarachnoid hemorrhage (SAH) incidence and outcomes. We examined trends from 1993-2020 in a long-running population-based stroke study conducted in the Greater Cincinnati Northern Kentucky (GCNK) region. Methods: Using a well-validated approach, we ascertained all incident nontraumatic SAHs among residents of the GCNK region in the following study periods; July 1993-June 94, calendar years 1999, 2005, 2010, 2015, and 2020. Potential cases were identified by ICD codes, abstracted, and then adjudicated by physicians. Aneurysmal SAH (aSAH) was defined as those with culprit aneurysms; cases with no available vessel imaging were considered aSAH if the hemorrhage volume was “massive” or if the patient died rapidly after onset. Incidence rates were compared over time using linear regression after normalizing to 2010 census demographics. The primary outcome assessed was unadjusted 30-day Case Fatality Rate (CFR), which was available through 2015. Results: We identified 518 SAH cases, of which 372 were aSAH (71.8%). Overall SAH incidence rate was stable over time, ranging from 8-10 cases per 100,000 person-years (Figure Panel A); however, the rate of aSAH showed a statistically significant decline, going from 7.2 cases/100,000 person-years in 1993 to 5.2 cases/100,000 person-years in 2020 (trend P =0.02). There was a nonsignificant increase in nonaneurysmal SAH ( P =0.09 for trend). Overall 30-day CFR declined significantly through 2015 ( P =0.006, Figure Panel B), driven predominantly by a decline in aSAH CFR (from 39.3% to 23.7%, trend P =0.04). Conclusion: We observed a significant decline in the incidence of aSAH from 1993-2020; however, overall SAH incidence was stable in the setting of numerically more nonaneurysmal SAHs. Further study is needed to understand the causes of this trend. 30-Day CFR has significantly improved both for overall SAH and for aSAH.

Nonaneurysmal perimesencephalic subarachnoid hemorrhage on noncontrast head CT: An accuracy, inter-rater, and intra-rater reliability study

Background and purposeTo evaluate the reliability and accuracy of nonaneurysmal perimesencephalic subarachnoid hemorrhage (NAPSAH) on Noncontrast Head CT (NCCT) between numerous raters. Materials and methods45 NCCT of adult patients with SAH who also had a catheter angiography (CA) were independently evaluated by 48 diverse raters; 45 raters performed a second assessment one month later. For each case, raters were asked: 1) whether they judged the bleeding pattern to be perimesencephalic; 2) whether there was blood anterior to brainstem; 3) complete filling of the anterior interhemispheric fissure (AIF); 4) extension to the lateral part of the sylvian fissure (LSF); 5) frank intraventricular hemorrhage; 6) whether in the hypothetical presence of a negative CT angiogram they would still recommend CA. An automatic NAPSAH diagnosis was also generated by combining responses to questions 2–5. Reliability was estimated using Gwet's AC1 (κG), and the relationship between the NCCT diagnosis of NAPSAH and the recommendation to perform CA using Cramer's V test. Multi-rater accuracy of NCCT in predicting negative CA was explored. ResultsInter-rater reliability for the presence of NAPSAH was moderate (κG = 0.58; 95%CI: 0.47, 0.69), but improved to substantial when automatically generated (κG = 0.70; 95%CI: 0.59, 0.81). The most reliable criteria were the absence of AIF filling (κG = 0.79) and extension to LSF (κG = 0.79). Mean intra-rater reliability was substantial (κG = 0.65). NAPSAH weakly correlated with CA decision (V = 0.50). Mean sensitivity and specificity were 58% (95%CI: 44%, 71%) and 83 % (95%CI: 72 %, 94%), respectively. ConclusionNAPSAH remains a diagnosis of exclusion. The NCCT diagnosis was moderately reliable and its impact on clinical decisions modest.

Contribution of Deep Cerebral Venous Anomaly to the Emergence of Nonaneurysmal Subarachnoid Hemorrhage as Opposed to Aneurysmal Subarachnoid Hemorrhage

The exact reason of nonaneurysmal subarachnoid hemorrhage (SAH) is an enigma. The aim of this study is to identify if type III deep cerebral venous drainage is exclusively prevalent in patients with nonaneurysmal SAH and to enumerate the predictors of poorer outcome in these patients. All patients of age >18years, presented at our centre with spontaneous SAH on noncontrast computed tomography head and were divided into 2 groups, aneurysmal and nonaneurysmal SAH after 4-vessel DSA. Based on the deep venous drainage pattern on both sides, basal venous drainage was found and classified into 3 types: type I, type II, and type III. The 3 groups were pitted against one another. Regression analysis were performed to predict the occurrence of nonaneurysmal-SAH with different types of basal vein. There were 100 nonaneurysmal SAH cases and 103 aneurysmal SAH cases. The mean age of presentation was 47.8±13.55years with slight male predominance (52%). The patients with type III venous drainage have 2 times more risk of developing nonaneurysmal SAH (95% confidence interval=1.21-4.31) as compared to those with aneurysmal SAH. On multivariate analysis, type III basal venous drainage, worse Hunt and Hess grade at presentation, extensive bleeding were predictors of an adverse outcome. The presence of type III venous distribution is associated with a 2-fold increase in the probability of having nonaneurysmal SAH, as well as a 3-fold increase in the risk of developing poorer neurological sequelae.

Asymptomatic subarachnoid hemorrhage following carotid endarterectomy: illustrative case.

Carotid endarterectomy (CEA) and carotid artery stenting are common surgical interventions for internal carotid artery stenosis. Cerebral hyperperfusion syndrome (CHS) is a well-known complication of both procedures that can lead to intracranial hemorrhage and worsen clinical outcomes. Here, the authors report a rare case of non-aneurysmal subarachnoid hemorrhage (SAH) following CEA and review the relevant literature. A 70-year-old woman with hypertension and diabetes presented with progressive visual loss in the right eye and was diagnosed with ocular ischemic syndrome. Imaging revealed severe right cervical carotid artery stenosis. CEA was performed with no complications. Postoperatively, the patient's blood pressure was tightly controlled, with no evidence of CHS. However, an asymptomatic SAH was detected on postoperative day 7. Careful observation and blood pressure control were maintained. Since follow-up magnetic resonance imaging (MRI) showed no enlarging of the SAH and the patient was asymptomatic, she was discharged on postoperative day 15 with a modified Rankin scale score of 0. This case highlights the potential occurrence of non-aneurysmal SAH as a rare complication of CEA, even in asymptomatic patients. Repeated postoperative MRI is necessary to detect such complications. It is crucial to carefully control blood pressure after CEA regardless of symptoms.

Stroke Unit as an alternative to Intensive Care Unit for initial hospital admission of low-grade non-aneurysmal subarachnoid haemorrhage: A safety and cost-minimisation analysis.

Stroke Units (SU) have been suggested as an alternative to Intensive Care units (ICU) for initial admission of low-grade non-aneurysmal spontaneous subarachnoid haemorrhage (naSAH). We hypothesised that the incidence of in-hospital complications and long-term clinical outcomes in low-grade naSAH patients would be comparable in both settings, and that a cost-minimisation analysis would favour the use of SU. Retrospective, single-centre study at a third-level stroke-referral hospital, including low-grade spontaneous naSAH patients with WFNS 1-2. Primary outcomes were death and functional status at 3 months. Secondary outcomes were incidence of in-hospital major neurological and systemic complications. Additionally, a cost-minimisation analysis was conducted to estimate the average cost savings that could be achieved with the most efficient approach. Out of 96 naSAH patients, 30 (31%) were initially admitted to ICU and 66 (69%) to SU. Both groups had similar demographic and radiological features except for a higher proportion of WFNS 2 in ICU subgroup. There were no statistically significant differences between ICU and SU-managed subgroups in death rate (2 (7%) and 1 (2%), respectively), functional outcome at 90 days (28 (93%) and 61 (92%) modified Rankin Scale 0-2) or neurological and systemic in-hospital complications. Cost-minimisation analysis demonstrated significant monetary savings favouring the SU strategy. Initial admission to the SU appears to be a safe and cost-effective alternative to the ICU for low-grade naSAH patients, with comparable clinical outcomes and a reduction of hospitalisation-related costs. Prospective multicenter randomised studies are encouraged to further evaluate this approach.

Management of perimesencephalic nonaneurysmal subarachnoid hemorrhage: a national survey

Perimesencephalic nonaneurysmal subarachnoid hemorrhage (NASAH) is a rare type of subarachnoid hemorrhage (SAH), usually associated with minor complications compared to aneurysmal SAH. Up to date, data is scarce and consensus on therapeutic management and follow-up diagnostics of NASAH is often missing. This survey aims to evaluate the clinical management among neurosurgical departments in Germany. 135 neurosurgical departments in Germany received a hardcopy questionnaire. Encompassing three case vignettes with minor, moderate and severe NASAH on CT-scans and questions including the in-hospital treatment with initial observation, blood pressure (BP) management, cerebral vasospasm (CV) prophylaxis and the need for digital subtraction angiography (DSA). 80 departments (59.2%) answered the questionnaire. Whereof, centers with a higher caseload state an elevated complication rate (Chi2 < 0.001). Initial observation on the intensive care unit is performed in 51.3%; 47.5%, 70.0% in minor, moderate and severe NASAH, respectively. Invasive BP monitoring is performed more often in severe NASAH (52.5%, 55.0%, 71.3% minor, moderate, severe). CV prophylaxis and transcranial doppler ultrasound (TCD) are performed in 41.3%, 45.0%, 63.8% in minor, moderate and severe NASAH, respectively. Indication for a second DSA is set in the majority of centers, whereas after two negative ones, a third DSA is less often indicated (2nd: 66.2%, 72.5%, 86.2%; 3rd: 3.8%, 3.8%, 13.8% minor, moderate, severe). This study confirms the influence of bleeding severity on treatment and follow-up of NASAH patients. Additionally, the existing inconsistency of treatment pathways throughout Germany is highlighted. Therefore, we suggest to conceive new treatment guidelines including this finding.

Intracranial Arachnoiditis and Hydrocephalus

A 62-year-old man presented a diffuse and predominantly cisternal acute nonaneurysmal subarachnoid hemorrhage associated with hydrocephalus. An external ventricular drain was placed, followed by clinical deterioration after its removal. At this point, a heavily T2-weighted high-resolution sequence of a brain magnetic resonance imaging showed acute hydrocephalus recrudescence and multiple arachnoid adhesions in the supravermian and interpeduncular cisterns, creating a loculated/cystic appearance. The diagnosis of intracranial arachnoiditis was made. Intracranial arachnoiditis results from meningeal inflammation. Fibrosis and adhesions at the subarachnoid spaces may follow, restricting cerebrospinal fluid circulation, particularly at the cranial base. Hydrocephalus probably resulted from the combination of subarachnoid hemorrhage and extensive scaring at the basal cisterns, precluding transdural and transvenous cerebrospinal fluid efflux. Heavily T2-weighted high-resolution magnetic resonance imaging sequences allow an exquisite depiction of arachnoiditis, displaying obstructive cisternal membranes, and contribute to better etiologic assessment and management of hydrocephalus.

The TCD hyperemia index to detect vasospasm and delayed cerebral ischemia in aneurysmal subarachnoid hemorrhage.

Elevated mean flow velocity (MFV) on transcranial Doppler (TCD) is used to predict vasospasm after aneurysmal subarachnoid hemorrhage (SAH). Hyperemia should be considered when observing elevated MFV. Lindegaard ratio (LR) is commonly used but does not enhance predictive values. We introduce a new marker, the hyperemia index (HI), calculated as bilateral extracranial internal carotid artery MFV divided by initial flow velocity. We evaluated SAH patients hospitalized ≥7 days between December 1, 2016 and June 30, 2022. We excluded patients with nonaneurysmal SAH, inadequate TCD windows, and baseline TCD obtained after 96 hours from onset. Logistic regression was conducted to assess the significant associations of HI, LR, and maximal MFV with vasospasm and delayed cerebral ischemia (DCI). Receiver operating characteristic analyses were employed to find the optimal cutoff value for HI. Lower HI (odds ratio [OR] 0.10, 95% confidence interval [CI] 0.01-0.68), higher MFV (OR 1.03, 95% CI 1.01-1.05), and LR (OR 2.02, 95% CI 1.44-2.85) were associated with vasospasm and DCI. Area under the curve (AUC) for predicting vasospasm was 0.70 (95% CI 0.58-0.82) for HI, 0.87 (95% CI 0.81-0.94) for maximal MFV, and 0.87 (95% CI 0.79-0.94) for LR. The optimal cutoff value for HI was 1.2. Combining HI <1.2 with MFV improved positive predictive value without altering the AUC value. Lower HI was associated with a higher likelihood of vasospasm and DCI. HI <1.2 may serve as a useful TCD parameter to indicate vasospasm and DCI when elevated MFV is observed, or when transtemporal windows are inadequate.

The impact of collateral status on cerebral vasospasm and delayed cerebral ischemia in subarachnoid hemorrhage.

Cerebral collateral circulation may affect subarachnoid hemorrhage (SAH) induced cerebral vasospasm and delayed cerebral ischemia. In this study our aim was to investigate the relationship between collateral status, vasospasm and delayed cerebral ischemia (DCI) in both aneurysmal and nonaneurysmal SAH. Patients diagnosed as SAH with and without aneurysm were included and their data investigated retrospectively. After the patients diagnosed as SAH according to cerebral computed tomography (CT)/magnetic resonance imaging (MRI), they underwent cerebral angiography to check for cerebral aneurysm. The diagnosis of DCI was made according to the neurological examination and control CT/MRI. All the patients had their control cerebral angiography on days 7 to 10 in order to assess vasospasm and also collateral circulation. The American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) Collateral Flow Grading System was modified to measure collateral circulation. A total of 59 patients data were analyzed. Patients with aneurysmal SAH had higher Fisher scores and DCI was more common. Although there was no statistically significant difference between the patients with and without DCI in terms of demographics and mortality, patients with DCI had worse collateral circulation and more severe vasospasm. These patients had higher Fisher scores and more cerebral aneurysm overall. According to our data, patients with higher Fisher scores, more severe vasospasm, and poor cerebral collateral circulation may experience DCI more frequently. Additionally aneurysmal SAH had higher Fisher scores and DCI was seen more common. To improve the clinical results for SAH patients, we believe that physicians should be aware of the DCI risk factors.

Management of Peri-mesencephalic Hemorrhage leading to acute hydrocephalus in an infant following Mild Trauma (P12-5.030)

<h3>Objective:</h3> To characterize etiology, risk factors, and management of peri-mesencephalic hemorrhage and severity of clinical presentation in pediatric populations <h3>Background:</h3> Peri-mesencephalic hemorrhage (PMH) is a form of mild subarachnoid hemorrhage (SAH) where the bleed is localized near the midbrain or just anterior to the pons without intraparenchymal or ventricular extension. It is typically a non-aneurysmal SAH (NASAH) with no clear source of bleeding after extensive vessel imaging including angiogram. Many hypotheses have been proposed such as spontaneous rupture of a perforating artery or an entirely venous source. Traumatic causes are rarely described. Outcomes are typically much better than aneurysmal SAH and other forms of NASAH with very low risk of rebleed, hydrocephalus, and little to no long-term neurologic deficits. <h3>Design/Methods:</h3> case study <h3>Results:</h3> An 8-month-old developmentally appropriate girl with no prior history of trauma who presented with three episodes of vomiting and lethargy 3–4 hours after a fall from standing position due to loss of balance while she was holding on to a folding chair. She fell backwards onto a tile floor and chair fell on top of her. CTH was obtained which showed prepontine and pontocerebellar hemorrhage spreading to ambient cisterns, IVH of the lateral and 3rd ventricles with acute noncommunicating hydrocephalus and no fracture. CTA with contrast and later MRI brain, MRA, and angiogram did not show any aneurysm or AVM per neurosurgery. EVD was placed with improvement in mental status. Repeat MRI brain was stable with very slight interval increase ventricle, and patient discharged home after 3rd ventriculostomy with no deficits. <h3>Conclusions:</h3> Though rare, trauma is a potential cause of PMH in pediatric populations and can present with acute hydrocephalus due to obstruction of ventricular system successfully treated with EVD placement and 3rd ventriculostomy with positive outcome. Hemorrhage may potentially be due to rupture of small perforating arteries through a sheering force. <b>Disclosure:</b> Dr. Johnson has nothing to disclose. Dr. Ming has nothing to disclose. Dr. Heshmati has nothing to disclose.

Re-Evaluating Risk Factors, Incidence, and Outcome of Aneurysmal and Non-Aneurysmal Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is one of the world's most life-threatening types of stroke. SAH can be classified into two main categories, aneurysmal (aSAH) and non-aneurysmal SAH (naSAH). In the present study, we aimed to prospectively evaluate SAH and its subcategories incidences, risk factors, complications, and outcomes in central Iran. All SAH patients diagnosed between 2016 and 2020 were included in Isfahan SAH Registry. Demographic, clinical characteristics, incidence rates (based on age categories), and laboratory/imaging findings were collected and compared between aSAH and naSAH subgroups. Complications during hospital stay and outcomes were also analyzed. Binary logistic regression analysis was performed to investigate the predictors of aSAH versus naSAH. Kaplan-Meier curves and Cox regression were used to evaluate the survival probability. A total of 461 SAH patients were included through Isfahan SAH Registry. The SAH annual incidence rate was 3.11 per 100,000 person-years. aSAH had higher incidence rate than naSAH (2.08/100,000 vs. 0.9/100,000 person-years, respectively). In-hospital mortality was 18.2%. Hypertension (P= 0.003) and smoking (P= 0.03) were significantly associated with aSAH, whereas diabetes mellitus (P < 0.001) was more associated with naSAH. After Cox regression analysis, there were higher hazard ratios for reduced in-hospital survival in conditions including altered mental status, Glasgow Coma Scale ≤13, rebleeding, and seizures. This study provided an updated estimation of SAH and its subgroups incidences in central Iran. Risk factors for aSAH are comparable to the ones reported in the literature. It is noteworthy that diabetes mellitus was associated with a higher incidence of naSAH in our cohort.

Non-Aneurysmal Perimesencephalic Subarachnoid Hemorrhage: A Literature Review.

Spontaneous non-aneurysmal subarachnoid haemorrhage (NAPMSAH) (addressing point 1) is a relatively rare occurrence in clinical settings as it is rarely misdiagnosed and usually involves a significantly better prognosis than the classical aneurysmal pattern. We hereby focused on a comprehensive analysis of this distinct pathological entity with the purpose of analysing possible pathophysiological entities, outcomes and treatment options involving this diagnosis with a focus on demographical, epidemiological and clinical data. The clinical setting includes focal neurological signs related to the anatomical structures, while computer tomography followed by tomographic angiography are the most common diagnosis tools, with a typical hyperdense lesion involving the midbrain, fourth ventricle and subthalamic areas without an angiographic correspondent, such as an aneurysmal pathology. Further investigations can also be used to highlight this diagnosis, such as interventional angiography or magnetic resonance imaging. Given the rarity of this condition and its relatively better prognosis, treatment options usually remain conservative. In the present review, the main characteristics of NAPMSAH are discussed.

Systemic Immune-Inflammation Index Predicts Acute Symptomatic Hydrocephalus After Spontaneous Nonaneurysmal Subarachnoid Hemorrhage

The authors sought to investigate the association between white blood cell counts and acute hydrocephalus in spontaneous nonaneurysmal subarachnoid hemorrhage (nSAH). We conducted a retrospective analysis of 105 consecutive patients with spontaneous nSAH. Univariate and multivariable logistic regression analyses were performed to investigate factors associated with hydrocephalus. Receiver operating characteristic curve analysis determined the optimal cutoff to differentiate between patients with and without hydrocephalus. The admission characteristics of hydrocephalic patients with aneurysmal and nSAH were compared. A total of 70 patients met inclusion criteria, of which 21 (30%) presented with hydrocephalus. In univariate logistic regression, leukocytes, neutrophils, lymphocytes, neutrophil-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, neutrophil-monocyte-to-lymphocyte ratio, and the systemic immune-inflammation (SII) index ([neutrophils× platelets/lymphocytes]/1000) were associated with hydrocephalus. After adjustments, the SII index independently predicted acute hydrocephalus with the highest odds among laboratory values (odds ratio 2.184, P=0.006). Receiver operating characteristic curve analysis revealed the SII index differentiated between patients with and without hydrocephalus (area under the curve=0.799, 95% CI: 0.688-0.909, P<0.001) with an optimal cutoff of 1.385 103/μL. SII indices did not differ between aneurysmal and nSAH patients with hydrocephalus (3.5 vs. 3.6 103/μL, P=0.795). A SII index ≥1.385 103/μL on admission predicts acute hydrocephalus in spontaneous nSAH. Hydrocephalic patients with aneurysmal and nSAH exhibit similar SII indices, and thus, an exaggerated inflammatory and thrombotic response follows spontaneous subarachnoid hemorrhage irrespective of hemorrhage etiology.

Abstract WP208: Cd14+ Monocytes Mediate The Immunological Environment In Aneurysmal Subarachnoid Hemorrhage Through Cxcl10 Secretion

Introduction: Robust evidence suggest that aneurysmal subarachnoid hemorrhage (aSAH) triggers a potent respone from innate and adaptive inmunities. An increase in CD8+CD161+ cells has been observed in the acute phase of patients with aSAH. However, the role of this cells is poorly understood. Methods: Cerebrospinal fluid of patients with aSAH and non-aneurysmal SAH (nasSAH) was analyzed. Single cell RNA sequencing (scRNAseq) of CD8+CD161+ cells sorted from the CSF of patients with aSAH was performed. Specific cell populations were identified based on gene clustering. Additionaly ten genes were identified. The levels of these genes were then quantified with real-time quantitative polymerase chain reaction (RT- qPCR) and were compared in patients with aSAH and patients with naSAH. Finally highly expressed proteins were quantified with ELISA. Results: Gene clustering suggested that CD14+ monocytes, NK cells and T cells expressed CD8+CD161+ in the CSF of patients with aSAH. Ten differentially expressed genes of clinical interest were then identified: CCL55, CCL7, APOE, SPP1, CXCL8, CXCL10, HMOX1, LTB, MAL, HLA-DRA1/HLA-DRB1 and their mRNA levels were quantied. CXCL10 and HMOX1 levels were higher in aSAH samples than in naSAH (p=0.02 and p=0.076, respectively). CXCL10 was the most significantly different expressed gene in aSAH compared to naSAH samples, and it was chosen for further analysis with ELISA. Protein levels of CXCL10 were higher in patients with aSAH [median(IQR) = 598(635) pg/mL] compared to patients with naSAH [median(IQR) = 31(214) pg/mL, p=0.04]. Conclusion: CD14+ monocytes, NK cells and T cells are CD8+CD161+ in patients with aSAH. CD14+ may be involved in the inflammatory response after aSAH through the expression of the pro-inflammatory cytokine CXCL10.

Angiographic Features of Intracranial Aneurisms in Mali: A Preliminary Study of 105 Patients

Introduction: Rupture of intracranial aneurisms leads to severe morbidity and mortality. There are two modalities of treatment surgery and endovascular treatment. The diagnosis is made by angiography (DSA, CTA, RMA). The angiographic features used to assess the risk of the complications and choose the treatment modality are size, location and aneurism morphology. Materials and Methods: We reviewed and analyzed the computed tomographic angiography and magnetic resonance angiography of all patients admitted to the hospital of Mali with IAs from 2015 to 2021 either 7 years. Patients who were less than 18 years old, those with non-aneurysmal SAH, patients who request a discharge and those with an incomplete angiographic description of the IAs were excluded from the analysis. Results: We have collected 105 patients with 109 aneurysms. The sex ratio was 2/1 in favor of females. The mean age was 44.51 years with the range from 18 to 70 years. The presentation mode was subarachnoid hemorrhage (SAH) in 97% of cases. 76.19% had confirmed high blood pressure before the bleeding. 19.04% were diabetics. 98% of our patients have made a CT angiography and 2% have made MR angiography for the aneurysm diagnosis. 97.24% of aneurisms were located in the anterior part of the Willis circle. 39.44% of these aneurisms were the anterior communicating complex aneurysm. 27.52% of aneurysm had a small size, 42.20% had a medium size, 20.18% large size against 5.50% of the giant (Figure 3) and the middle cerebral artery was the most involved in the least. 95.41% of cases were saccular aneurysms against 4.59% fusiform. Conclusion: The angiographic feature of an intracranial aneurism in the Malian population may differ from other populations of the sub-region. The anterior communicating complex aneurysm is more common and the aneurism of the posterior part of the Willis circle is less common. We found the aneurism size ≥ 6 mm, ACA, MCA and Pcom more frequent.

A Case of Quadrigeminal Variant of Perimesencephalic Nonaneurysmal Subarachnoid Hemorrhage

AbstractThe incidence of perimesencephalic subarachnoid hemorrhage (PMSAH) is rare, 0.5 in 100,000 adults. It comprises 5 to 10% of all SAHs and approximately 33% of all nonaneurysmal SAH. Quadrigeminal SAH is a variant of perimesencephalic nonaneurysmal subarachnoid hemorrhage (PMNASAH) that is not well described in the literature. It may comprise up to one-fifth of PMNASAH cases and carries a similar benign prognosis. This variant of PMSAH is characterized by blood centered in the quadrigeminal cistern and limited to the superior vermian and posterior perimesencephalic cisterns. Noncontrast computed tomography of the brain is the initial investigation of choice, while four-vessel cerebral angiogram is the gold standard for the diagnosis of SAH.We report a case at our institute.

Hydrocephalus, cerebral vasospasm, and delayed cerebral ischemia following non-aneurysmatic spontaneous subarachnoid hemorrhages: an underestimated problem

Non-aneurysmal subarachnoid hemorrhage (NASAH) is rare and mostly benign. However, complications such as cerebral vasospasm (CV), delayed cerebral ischemia (DCI), or post-hemorrhagic hydrocephalus (HC) may worsen the prognosis. The aim of this study was to evaluate the rate of these complications comparing perimesencephalic (PM) and non-perimesencephalic (NPM) SAH. Monocentric, retrospective analysis of patients diagnosed with NASAH from 01/2010 to 01/2021. Diagnosis was set only if vascular pathologies were excluded in at least one digital subtraction angiography, and NASAH was confirmed by cranial computed tomography (cCT) or lumbar puncture (LP). One hundred patients (62 female) with a mean age of 54.9 years (27–84) were identified. Seventy-three percent had a World Federation of Neurological Surgeons (WFNS) grading scale score I, while 9% were WFNS score IV or V at the time of admission. SAH was diagnosed by cCT in 86%, in 14% by lumbar puncture. Twenty-five percent necessitated short-term CSF diversion by extraventricular drainage or lumbar drainage, whereof 7 suffered from long-term HC treated with ventriculoperitoneal shunting (VPS). One patient without a short-term CSF drainage developed long-term HC. Ten percent developed CV, four of whom received intraarterial spasmolysis. Radiological DCI was diagnosed in 2%; none of these correlated with CV. Despite a mortality of 3% occurring solely in NPM SAH, the analyzed complication rate was comparable in both groups. We observed post-hemorrhagic complications in 35% of cases during the first 3 weeks after bleeding, predominantly in patients with NPM SAH. For this reason, close observation and cranial imaging within this time may be indicated not to overlook these complications.