Non-aneurysmal non-traumatic subarachnoid hemorrhage: patient characteristics, clinical outcome and prognostic factors based on a single-center experience in 125 patients

Subarachnoid haemorrhage in the emergency department (SHED): a prospective, observational, multicentre cohort study

BACKGROUND

People presenting to the ED with acute severe headache often undergo investigation to exclude subarachnoid haemorrhage (SAH). International guidelines propose that brain imaging within 6 hours of headache onset can exclude SAH, in isolation. The safety of this approach is debated. We sought to externally validate this strategy and evaluate the test characteristics of CT-brain beyond 6 hours.

METHODS

A prospective, multicentre, observational cohort study of consecutive adult patients with non-traumatic acute headache presenting to the ED within a UK National Health Service setting. Investigation, diagnosis and management of SAH were all performed within routine practice. All participants were followed up for 28 days using medical records and direct contact as necessary. Uncertain diagnoses were independently adjudicated.

RESULTS

Between March 2020 and February 2023, 3663 eligible patients were enrolled from 88 EDs (mean age 45.8 (SD 16.6), 64.1% female). 3268 patients (89.2%) underwent CT-brain imaging. There were 237 cases of confirmed SAH, a prevalence of 6.5%. CT within 6 hours of headache onset (n=772) had a sensitivity of 97% (95% CI 92.5% to 99.2%) for the diagnosis of SAH and a negative predictive value of 99.6% (95% CI 98.9% to 99.9%). The post-test probability after a negative CT within 6 hours was 0.5% (95% CI 0.2% to 1.3%). The negative likelihood ratio was 0.03 (95% CI 0.01 to 0.08). CT within 24 hours of headache onset (n=2008) had a sensitivity of 94.6% (95% CI 91.0% to 97.0%). Post-test probability for SAH was consistently less than 1%. For aneurysmal SAH, post-test probability was 0.1% (95% CI 0.0% to 0.4%) if the CT was performed within 24 hours of headache onset.

CONCLUSION

Our data suggest a very low likelihood of SAH after a negative CT-brain scan performed early after headache onset. These results can inform shared decision-making on the risks and benefits of further investigation to exclude SAH in ED patients with acute headache.

Risk Factors for Cerebral Vasospasm After Subarachnoid Hemorrhage: A Systematic Review of Observational Studies

Cerebral vasospasm (CV) following subarachnoid hemorrhage (SAH) remains one of the leading causes of high mortality and poor outcomes. Understanding the risk factors associated with CV is pivotal to improving patients' outcomes. We conducted an extensive search for analytical observational studies that analyzed the correlation between various variables and the likelihood of CV development among adult patients with SAH (age ≥ 18 years). Five scholar databases were used, namely, PubMed, EBSCO, Web of Science, Science Direct, and Google Scholar. Relevant studies published between January 1st, 2016, and August 9th, 2023, were included. The Newcastle-Ottawa Scale was adopted to assess the risk of bias among included observational studies. A total of 33 studies met the inclusion criteria. Of the 24,958 patients with SAH who were identified, 6,761 patients had a subsequent CV (27.1%). Several statistically significant risk factors were reported across the literature. Younger age, female sex, smoking, alcohol intake, modified Fisher grade 3-4, higher Hunt and Hess grading, and the presence of multiple comorbidities (diabetes, hypertension, congestive heart failure, and history of stroke) were among the well-established risk factors for CV. Additionally, leukocytosis was consistently reported to be a significant predictor in multiple studies, providing compelling evidence for its association with CV. Even though single studies reported an association between CV and certain variables, further research is necessary to investigate the implications of these findings. These include arterial tortuosity, hypokalemia, potassium to glucose gradient, hypoalbuminemia, anemia, von Willebrand factor and vascular endothelial growth factor, use of desflurane, and hemodynamic stability. Overall, this systemic review provides a comprehensive summary of the current data that evaluates the potential risk factors for the development of CV after SAH. However, because of data heterogeneity, certain factors require further validation in their correlation with CV development. Larger-scale observational and clinical trials are mandatory to extensively investigate the significant predictors of CV to lay the scientific foundation for improving outcomes in susceptible patients with SAH.

Sex Differences in Case Fatality of Aneurysmal Subarachnoid Hemorrhage: A Systematic Review

INTRODUCTION

Aneurysmal subarachnoid hemorrhage (SAH) is more common in women than in men, contrary to most cardiovascular diseases. However, it is unclear whether the case fatality rate (CFR) of SAH also differs by sex. Thus, we performed a systematic review to address the relationship between sex and SAH CFRs.

METHODS

We conducted a systematic literature search in PubMed, Scopus, and Cochrane library databases. We focused on population-based studies that included both nonhospitalized and hospitalized SAHs and had either reported 1-month (28-31 day) SAH CFRs separately for men and women or calculated risk estimates for SAH CFR by sex. For quality classification, we used the Cochrane Collaboration Handbook and Critical Appraisal Skills Program guidelines. We pooled the study cohorts and calculated relative risk ratios (RRs) with 95% confidence intervals (CIs) for SAH death between women and men using a random-effects meta-analysis model.

RESULTS

The literature search yielded 5,592 initial publications, of which 33 study cohorts were included in the final review. Of the 33 study cohorts, only three reported significant sex differences, although the findings were contradictory. In the pooled analysis of all 53,141 SAH cases (60.3% women) from 26 countries, the 1-month CFR did not differ (RR = 0.99 [95% CI: 0.93-1.05]) between women (35.5%) and men (35.0%). According to our risk-of-bias evaluation, all 33 study cohorts were categorized as low quality. The most important sources of bias risks were related to the absence of proper confounding control (all 33 study cohorts), insufficient sample size (27 of 33 study cohorts), and poor/unclear diagnostic accuracy (27 of 33 study cohorts).

CONCLUSION

Contrary to SAH incidence rates, the SAH CFRs do not seem to differ between men and women. However, since none of the studies were specifically designed to examine the sex differences in SAH CFRs, future studies on the topic are warranted.

Epidemiology and treatment of atraumatic subarachnoid hemorrhage over 10 years in a population-based registry

INTRODUCTION

Incidence of atraumatic subarachnoid hemorrhage (SAH) is decreasing over time and its treatment is changing. We reported epidemiologic data on aneurysmal (a-) and non-aneurysmal (na-) SAH over 10 years.

PATIENTS AND METHODS

Our prospective population-based registry included patients with first-ever SAH occurring from January 2011 to December 2020. Clinical and neuroimaging records were screened to evaluate the presence and location of intracranial aneurysms, to identify naSAH subtypes and to retrieve information on surgical treatments. Incidence rates were standardized to the 2011 Italian and European population. We also estimated 30-day and 1-year case-fatality rates after SAH. Multivariate hazard ratios for 30-days and 1-year fatality were estimated with Cox regression analysis.

RESULTS

194 patients (60.8% women; mean age 62.5 ± 16.0 years) were included (76.8% aSAH and 23.2% naSAH). The crude incidence rates per 100,000 person-years of SAH, aSAH, and naSAH were 6.5 (95% CI 5.6-7.5), 5.0 (95% CI 4.2-5.9), and 1.5 (95% CI 1.1-2.0), respectively, and remained stable over time. Compared to aSAH, naSAH patients had higher age (68.8 ± 19.7 yearsvs 60.6 ± 14.2 years; p = 0.012), lower cigarette smoking (17.9%vs 36.4%; p < 0.001) and higher atrial fibrillation (15.7% vs 2.8%; p = 0.005). SAH case-fatality rates within 30-days and 1-year were 28.4% (95% CI 21.4-36.9) and 37.1% (95% CI 29.0-46.7), respectively. The relative proportion of surgically treated patients did not change over time.

CONCLUSION

We found a low and stable incidence of SAH over the 2011-2020 period. naSAH remained rare and deserves further investigation in larger prospective cohorts.

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

BACKGROUND

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.

METHODS

All patients of age >18 years, 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.

RESULTS

There were 100 nonaneurysmal SAH cases and 103 aneurysmal SAH cases. The mean age of presentation was 47.8 ± 13.55 years 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.

CONCLUSIONS

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.

GFAP and UCHL1 in Non-traumatic SAH: The Story thus Far. A Systematic Review of the Literature

OBJECTIVE

Non-traumatic subarachnoid hemorrhage (SAH) is associated with a high percentage of misdiagnosis and poor prognosis. Biomarkers could be useful in the identification, treatment/management guidance, and outcome improvement of SAH patients. The current systematic review aims to investigate the potential role of biomarkers GFAP (Glial Fibrillary Acidic Protein) and UCH-L1 (Ubiquitin C-Terminal Hydrolase L1) in the diagnosis and prognosis of non-traumatic SAH.

METHODS

A systematic search of PubMed, Scopus, and Web of Science databases was conducted from their inception through February 2023.

RESULTS

17 studies met the inclusion criteria and were included in this review. The vast majority of the included studies (82%) were on GFAP. Most studies used blood and/or CSF samples and incorporated multiple measurements through the initial hospitalization days. The majority of identified studies reported significantly higher levels of GFAP and UCHL1 in SAH patients with poor outcomes. There was notable variation in the specimen type and the timing of sampling.

CONCLUSION

Quantification of GFAP and UCHL1 through the initial days of hospitalization shows promise in the prediction of SAH patient outcomes. Further research is nevertheless warranted to confirm these findings and further clarify the use of the two biomarkers in SAH diagnosis and the prediction of severity and secondary events.

An Epidemiological Investigation on Patients with Non-traumatic Subarachnoid Hemorrhage from 2010 to 2020

Objective

Subarachnoid hemorrhage (SAH) is still considered a life-threatening medical condition with a high mortality rate, particularly in developing countries. Thus, the present study aimed to investigate the angiographic findings of non-traumatic or spontaneous SAH.

Methods

This retrospective cohort study included 642 health records of patients with non-traumatic SAH over a 10-year period, from 2010 to 2020. The required data, including demographic information, aneurysm type, size, location, disease severity classification, and secondary complications, were extracted.

Results

The study included 642 patients, with 262 (40.8%) being male. The mean age of the participants was 54.72±13.51 years. The most prevalent type of aneurysm was saccular (89.1%), while serpentine (0.2%) and dissecting saccular (0.2%) aneurysms had the least prevalence. The most frequently involved arteries were the anterior communicating artery (ACoA; 38%), internal carotid artery (ICA; 27.6%), and middle cerebral artery (MCA; 13.4%). There was a significant correlation between sex and aneurysms occurring at ACoA and ICA (p< 0.0001), and ACoA - A1 (p=0.02). Patient age and sex were also significantly correlated with one another (p<0.0001). There was no statistically significant correlation between sex, aneurysm size, Glasgow coma scale (GCS), and modified Rankin scale (MRS).

Conclusion

Based on our findings, the presence of aneurysms at ACoA, ACoA - A1, and ICA should be thoroughly ruled out in patients with severe headaches of sudden onset, particularly male patients of younger ages.

Long-term Course of Cognitive Functioning After Aneurysmal and Angiographically Negative Subarachnoid Hemorrhage

BACKGROUND AND OBJECTIVES

Cognitive impairment is a common consequence of subarachnoid hemorrhage (SAH), negatively affecting everyday functioning. This study is the first to investigate the long-term course of cognitive functioning after SAH and its associations with long-term well-being (ie, anxiety and depression), cognitive complaints, and return to work, separately for patients with aneurysmal SAH (aSAH) and angiographically negative SAH (anSAH) in a longitudinal design.

METHODS

Cognitive functioning was measured at 2 time points (T1: 3-6 months post-SAH; T2: 2-4 years post-SAH) in 58 patients with aSAH and 22 patients with anSAH with neuropsychological tests for (working) memory, psychomotor speed, and attention/executive functioning. Questionnaires were used to measure cognitive complaints and well-being at T1 and T2 and return to work at T2.

RESULTS

At T2, patients with aSAH only showed improvements in memory and on an executive functioning and psychomotor speed subtest, whereas in contrast, patients with anSAH had significantly poorer scores on tests for psychomotor speed. A significant amount of patients with aSAH and anSAH still reported cognitive complaints, anxiety, and depression in the chronic stage. Cognitive functioning was not significantly associated with cognitive complaints in both SAH groups. On the other hand, cognitive complaints were related to well-being at the long-term in both SAH groups. More cognitive complaints were also associated with more difficulties in return to work in patients with aSAH.

CONCLUSION

Patients with aSAH and anSAH have cognitive impairments at the subacute stage post-SAH, and these impairments persist into the chronic stage. Moreover, both SAH groups still reported decreased well-being in the chronic stage post-SAH, related to cognitive complaints but not to cognitive impairment. For clinical practice, an early neuropsychological assessment will already provide relevant information to estimate long-term cognitive impairment, but in addition, it is important to pay attention to psychological distress at the long-term.

Frequency and Characteristics of Spinal Bleeding Sources in Nontraumatic Angiogram-Negative Subarachnoid Hemorrhage

INTRODUCTION

Angiogram-negative subarachnoid hemorrhage (AN-SAH) accounts for 5-15% of spontaneous SAH. This study aims to analyze the frequency and characteristics of spinal bleeding sources in patients with AN-SAH.

METHODS

140 patients suffering from AN-SAH treated at our institution from 2012 to 2022 were included in this retrospective cohort study.

RESULTS

52.1% were diagnosed with perimesencephalic SAH, 35.0% with non-perimesencephalic, SAH and 12.9% with CT-negative SAH (diagnosed by lumbar puncture). Additional magnetic resonance imaging (MRI) identified a spinal bleeding source in 4 patients (2.86%). These patients presented with local spine pain or neurological deficits (relative risk: 3.9706 [95% confidence interval [CI]: 0.7272-21.6792]; p < 0.001) and were younger (mean difference 14.85 years [95% CI: 0.85-28.85; p = 0.038]) compared to patients without a spinal bleeding source.

CONCLUSIONS

AN-SAH caused by spinal pathology is rare. This study indicates that craniocervical and holospinal MRI should be considered in AN-SAH, especially for young patients with AN-SAH who present with back pain or neurological deficits.

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

OBJECTIVE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Clinical outcome and prognostic factors of patients with non-traumatic angiography-negative subarachnoid hemorrhage

Purpose

The cause of spontaneous subarachnoid hemorrhage (SAH) is unknown in 10% of cases. The aim of this study was to demonstrate the characteristics of patients with angiography-negative subarachnoid hemorrhage (anSAH) and to analyze factors influencing the clinical outcome in patients suffering from anSAH.

Methods

A retrospective cohort of 75 patients with anSAH [26 perimesencephalic (pmSAH) and 49 non-perimesencephalic SAH (npmSAH)] admitted between January 2016 and June 2022 was included. We analyzed demographic, clinical data and 6-month functional outcomes. Enter regression analysis was performed to identify factors associated with outcomes.

Results

Unfavorable outcome was achieved in 10 of 75 patients (13.3%). Unfavorable outcome was associated with senior adults (p = 0.008), Hijdra cistern score (HCS) elevation (p = 0.015), long-time lumbar cistern continuous drainage (LCFD; p = 0.029) and hydrocephalus (p = 0.046). The only significant risk factor for unfavorable outcome after npmSAH was the HCS (OR 1.213 (95%CI 1.007-1.462), p = 0.042).

Conclusion

Our study provides valuable information on both SAH patterns and functional outcome in patients suffering from anSAH and should be taken into consideration during management of these patients.

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.

Systemic Inflammatory Response in Spontaneous Subarachnoid Hemorrhage from Aneurysmal Rupture versus Subarachnoid Hemorrhage of Unknown Origin

OBJECTIVE

It is well known that spontaneous non-aneurysmal subarachnoid hemorrhage (SAH), also known as sine materia SAH (smSAH), has usually a better course and prognosis than its aneurysmal counterpart (aSAH). This might depend on different inflammatory mechanisms initiated by bleeding events of different origins. The aim of the present study was to explore the systemic inflammatory response in spontaneous SAH, comparing aSAH and smSAH.

METHODS

We performed a prospective observational study over a consecutive series of patients with SAH. For these patients, we collected all clinical data and, furthermore, performed venous blood sampling over six time points to analyze blood cells. We further performed the analysis of lymphocytes and monocytes by means of flow cytometry to quantify common subtypes. Statistical analysis included a t-student test, Chi-square test, multivariate logistic regression, and ROC analysis.

RESULTS

48 patients were included: six (12.5%) with a diagnosis of spontaneous smSAH, and forty-two patients (87.5%) with aSAH. Significant differences on Day 0 were found for neutrophils and a systemic neuro-inflammatory index, namely, systemic inflammatory response index (SIRI). At the ROC analysis, neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and SIRI exhibited satisfactory predictive power on day 0. At the multivariable logistic regression analysis, the combined index (NLR, LMR, SIRI at day 0) yielded an OR of 0.59 (95% CI 0.29-1.21]). LMR at day 0 yielded an OR of 1.25 ([95% CI 0.94-1.68]), NLR at day 0 exhibited an OR of 0.68 ([95% CI 0.42-1.09]), and SIRI at day 0 displayed an OR of 0.31 ([95% CI 0.06-1.49]).

CONCLUSION

This preliminary study indicated a possible role of some inflammatory indices that point out the importance of innate and adaptive immunity in the etiopathogenetic mechanisms. Drugs modulating these responses could eventually counteract or, at least, reduce secondary damage associated with SAH.

Nonaneurysmal subarachnoid hemorrhage associated with COVID-19 infection: A case report

Background:

Most coronavirus disease 2019 (COVID-19)-related cerebrovascular disorders are ischemic while hemorrhagic disorders are rarely reported. Among these, subarachnoid hemorrhage (SAH) is very rarely reported and nonaneurysmal SAH has been reported in only about a dozen cases. Here, we report a case of nonaneurysmal SAH as the only clinical manifestation of COVID-19 infection. In addition, we reviewed and analyzed the literature data on cases of nonaneurysmal SAH caused by COVID-19 infection.

Case Description:

A 50-year-old woman presented to an emergency department with a sudden headache, right hemiparesis, and consciousness disturbance. At that time, no fever or respiratory failure was observed. Laboratory data were within normal values but the rapid antigen test for COVID-19 on admission was positive, resulting in a diagnosis of COVID-19 infection. Computed tomograms (CTs) showed bilateral convexal SAH with a hematoma but three-dimensional CT angiograms showed no obvious sources, such as a cerebral aneurysm. Therefore, the patient was diagnosed with nonaneurysmal SAH associated with COVID-19 infection. With conservative treatment, consciousness level and hemiparesis both improved gradually until transfer for continued rehabilitation. Approximately 12 weeks after onset, the patient was discharged with only mild cognitive impairment. During the entire course of the disease, the headache, hemiparesis, and mild cognitive impairment due to nonaneurysmal SAH with small hematoma were the only abnormalities experienced.

Conclusion:

Since COVID-19 infection can cause nonaneurysmal hemorrhaging, it should be considered (even in the absence of characteristic infectious or respiratory symptoms of COVID-19) when atypical hemorrhage distribution is seen as in our case.

The relationship between non-aneurysmal spontaneous subarachnoid hemorrhage and basilar tip anatomy

OBJECTIVE

Non-aneurysmal spontaneous subarachnoid hemorrhage (NASAH) has a good prognosis, but its cause has not been clearly identified. In this study, we assessed the clinical and radiological features of NASAH and suggested an anatomical relationship between the basilar tip anatomy and NASAH.

METHODS

From August 2013 to May 2020, 21 patients were diagnosed with NASAH at our institution. We evaluated the clinical features of NASAH. NASAH was classified into a perimesencephalic pattern and aneurysmal pattern according to the distribution of hemorrhage based on initial brain computed tomography. Digital subtraction angiography was used to classify the basilar tip anatomy into symmetric cranial fusion, symmetric caudal fusion, or asymmetric fusion types.

RESULTS

Of the 21 patients, twenty patients had a good clinical outcome (modified Rankin Scale (mRS) 1-2; Glasgow Outcome Scale (GOS) 4-5). These patients showed improvement in mRS and Glasgow Coma Scale (GCS) at the last follow-up (P=.003 and P=.016, respectively). Eighteen patients with NASAH (85.7%) had the caudal fusion type, and only three patients with NASAH (14.3%) had the cranial fusion type. Seven patients with the perimesencephalic pattern (77.8%) had the caudal fusion type, and eleven patients with the aneurysmal pattern (91.7%) had the caudal fusion type.

CONCLUSIONS

In NASAH patients, the caudal fusion tends to occur frequently among patients with basilar tip anatomy. In the case of the caudal fusion, the perforators around the basilar tip would be more susceptible to hemodynamic stress, which could contribute to the occurrence of NASAH.

Clinical Outcome and Prognostic Factors of Patients with Perimesencephalic and Nonperimesencephalic Subarachnoid Hemorrhage

OBJECTIVE

To demonstrate the clinical outcome of patients with nonperimesencephalic subarachnoid hemorrhage (npSAH) compared with patients with aneurysmal SAH (aSAH) and perimesencephalic SAH (pSAH) and to evaluate predictive value of various clinical and radiological findings in patients with npSAH.

METHODS

We retrospectively identified patients with SAH who presented at our institution between 2009 and 2018. We analyzed demographic and clinical data and outcomes. Multivariable analysis was performed for outcome parameters.

RESULTS

Of 608 patients with confirmed SAH, 78% had aSAH, and 22% had nonaneurysmal SAH. Nonaneurysmal SAH was perimesencephalic in 30% of cases and nonperimesencephalic in 70%. Initial clinical status (Hunt and Hess score) was significantly worse in patients with aSAH compared with patients with nonaneurysmal SAH. Complications such as delayed cerebral ischemia occurred significantly more often in patients with aSAH. Patients with pSAH had a more favorable clinical course than patients with aSAH or npSAH. There was no significant difference in 30-day mortality between aSAH (29%) and npSAH (28%) patients (P = 0.835). Hunt and Hess score emerged as a strong predictor of unfavorable outcome in both aSAH and npSAH in multivariable regression.

CONCLUSIONS

Patients with npSAH had a similar clinical outcome as patients with aSAH, although there were significantly fewer clinical complications in patients with npSAH. Patients with pSAH demonstrated an overall good clinical course. Our multivariable analysis showed that initial Hunt and Hess score was an important predictor for clinical outcome in aSAH as well as npSAH.

Effect of stress-induced hyperglycemia after non-traumatic non-aneurysmal subarachnoid hemorrhage on clinical complications and functional outcomes

Background

Despite having an overall benign course, non‐traumatic non‐aneurysmal subarachnoid hemorrhage (naSAH) is still accompanied by a risk of clinical complications and poor outcomes. Risk factors and mechanisms of complications and poor outcomes after naSAH remain unknown. Our aim was to explore the effect of stress‐induced hyperglycemia (SIH) on complication rates and functional outcomes in naSAH patients.

Methods

We retrospectively reviewed patients with naSAH admitted to our institution between 2013 and 2018. SIH was identified according to previous criterion. Symptomatic vasospasm, delayed cerebral infarction, and hydrocephalus were identified as main complications. Outcomes were reviewed using a modified Rankin Scale (mRS) at discharge, 3 months, and 12 months. A statistical analysis was conducted to reveal the associations of SIH with complications and outcomes.

Results

A total of 244 naSAH patients were included in the cohort with 74 (30.3%) SIH. After adjusting for age, gender, hypertension, Hunt and Hess (HH) grade, modified Fisher Scale (mFS), intraventricular hemorrhage (IVH), and subarachnoid blood distribution, SIH was significantly associated with symptomatic vasospasm (p < 0.001, 12.176 [4.904–30.231]), delayed cerebral infarction (p < 0.001, 12.434 [3.850–40.161]), hydrocephalus (p = 0.008, 5.771 [1.570–21.222]), and poor outcome at 12 months (p = 0.006, 5.506 [1.632–18.581]), whereas the correlation between SIH and poor outcome at discharge (p = 0.064, 2.409 [0.951–6.100]) or 3 months (p = 0.110, 2.029 [0.852–4.833]) was not significant. Incorporation of SIH increased the area under curve (AUC) of ROC in the combined model for predicting symptomatic vasospasm (p = 0.002), delayed cerebral infarction (p = 0.024), hydrocephalus (p = 0.037), and 12‐month poor outcome (p = 0.087).

Conclusions

SIH is a significant and independent risk factor for symptomatic vasospasm, delayed cerebral infarction, hydrocephalus, and long‐term poor outcome in naSAH patients. Identifying SIH early after naSAH is important for decision‐making and treatment planning.

Could outcomes of intracranial aneurysms be better predict using serum creatinine and glomerular filtration rate?

Purpose:

To analyze the role of serum creatinine levels as a biomarker of intracranial aneurysm outcomes.

Methods:

This is a prospective analysis of outcomes of patients with intracranial aneurysm. One hundred forty-seven patients with serum creatinine at admission and 6 months follow up were included. Linear and logistic regressions were used to analyze the data. Modified Rankin scale (mRS) was used to assess outcome.

Results:

Creatinine level was not directly related to aneurysm outcome nor aneurysm rupture (p > 0.05). However, patients with a glomerular filtration rate (GFR) lower than 72.50 mL·min^–1 had an odds ratio (OR) of 3.049 (p = 0.006) for worse outcome. Similarly, aneurysm rupture had an OR of 2.957 (p = 0.014) for worse outcomes. Stepwise selection model selected 4 variables for outcomes prediction: serum creatinine, sex, hypertension and treatment. Hypertensive patients had, on average, an increase in 0.588 in mRS (p = 0.022), while treatment with microsurgery had a decrease in 0.555 (p = 0.038).

Conclusions:

Patients with higher GFR had better outcomes after 6 months. Patients with higher GFR had better outcomes after 6 months. Creatinine presented an indirect role in GFR values and should be included in models for outcome prediction.

Prevalence and Outcomes of Bicuspid Aortic Valve in Patients With Aneurysmal Sub-Arachnoid Hemorrhage: A Prospective Neurology Registry Report

Background Intracranial aneurysms are reported in 6%-10% of patients with bicuspid aortic valve (BAV), and routine intracranial aneurysm surveillance has been advocated by some. We assessed the prevalence and features of the most important patient-outcome: aneurysmal sub-arachnoid hemorrhage (aSAH), as compared with controls without aSAH, and tricuspid aortic valve (TAV) with aSAH. Methods and Results Adult patients with accurate diagnosis of aSAH and at least one echocardiogram between 2000 and 2019 were identified from a consecutive prospectively maintained registry of aSAH admissions. Controls without a diagnosis of SAH were age- and sex-matched. BAV prevalence was confirmed echocardiographically. Severity of aSAH was categorized using modified Fisher and World Federation of Neurological Scale. Neurologic outcome was assessed using modified Rankin score. A total 488 aSAH cases and 990 controls were identified and BAV status was confirmed. Prevalence of BAV in patients with aSAH was 1.2% (6/488) versus 3.5% (35/990) in controls, P=0.01. BAV+aSAH were noted to be younger than TAV+aSAH (56±11 versus 68±14; P=0.03) with smaller aneurysms (5±2 versus 7±4; P=0.31). The severity of aSAH was lesser in BAV+aSAH than TAV (modified Fisher grade>2 50% versus 74%; P=0.19, World Federation of Neurological Scale grade>3 17% versus 36%; P=0.43). BAV+aSAH had less severe neurologic disability (modified Rankin score 3%-6 33% versus 49% in TAV; P=0.44) and comparable in-hospital mortality rates (P=0.93). BAV had lower odds for aSAH on multivariate analysis (odds ratio 0.23[CI 0.08-0.65]; P=0.01). Conclusions Prevalence of BAV was 3 times lower in the aSAH registry than in controls without aSAH. BAV+aSAH had clinically smaller aneurysms, clinically smaller bleeds, and better neurologic outcome as compared with TAV+aSAH, which needs to be confirmed in larger studies. These findings argue against routine surveillance for intracranial aneurysms in patients with BAV without aortic coarctation.

Spontaneous angiogram-negative subarachnoid hemorrhage: a retrospective single center cohort study

Background

Spontaneous angiogram-negative subarachnoid hemorrhage (SAH) is considered a benign illness with little of the aneurysmal SAH-related complications. We describe the clinical course, SAH-related complications, and outcome of patients with angiogram-negative SAH.

Methods

We retrospectively reviewed all adult patients admitted to a neurosurgical intensive care unit during 2004–2018 due to spontaneous angiogram-negative SAH. Our primary outcome was a dichotomized Glasgow Outcome Scale (GOS) at 3 months. We assessed factors that associated with outcome using multivariable logistic regression analysis.

Results

Of the 108 patients included, 84% had a favorable outcome (GOS 4–5), and mortality was 5% within 1 year. The median age was 58 years, 51% were female, and 93% had a low-grade SAH (World Federation of Neurosurgical Societies grading I–III). The median number of angiograms performed per patient was two. Thirty percent of patients showed radiological signs of acute hydrocephalus, 28% were acutely treated with an external ventricular drain, 13% received active vasospasm treatment and 17% received a permanent shunt. In the multivariable logistic regression model, only acute hydrocephalus associated with unfavorable outcome (odds ratio = 4.05, 95% confidence interval = 1.05–15.73). Two patients had a new bleeding episode.

Conclusion

SAH-related complications such as hydrocephalus and vasospasm are common after angiogram-negative SAH. Still, most patients had a favorable outcome. Only acute hydrocephalus was associated with unfavorable outcome. The high rate of SAH-related complications highlights the need for neurosurgical care in these patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00701-021-05069-7.

Factors determining outcome of post-angiogram-negative subarachnoid hemorrhage

Aim:

To determine the risk factors affecting outcome at the end of 90 days of post-angiogram-negative subarachnoid hemorrhage (SAH).

Methods:

Non-traumatic SAH cases were reviewed from the case records of patients who had reported to the Department of Neurology of a tertiary care hospital and 50 angio-negative SAH cases were included after excluding all the cases with known cause of hemorrhage after doing computed tomography angiography (CTA)/digital subtraction angiography (DSA). The presence of hypertension, diabetes mellitus, coronary artery disease (CAD), history of alcohol and smoking, and various scales like Hunt and Hess Scale (HHS), World Federation of Neurological Surgeons (WFNS), and Fisher scale had been recorded at admission. The outcome was assessed at 90 days post-SAH using the Modified Rankin Scale (mRS).

Statistical analyses:

The association between the outcome and the factors was assessed using the Pearson Chi-Square test and the risk factors/predictors of outcome were assessed using logistic regression.

Results:

The following variables were important risk factors for predicting poor outcome of angio-negative SAH (mRS 3 to 6): hypertension (P = 0.011), diabetes mellitus (P = 0.032), being an alcoholic (P = 0.019), HHS grade 4 to 5 (P < 0.01), and WFNS grade 4 to 5 (P < 0.01). On multivariate regression analysis, hypertension (P = 0.032) was an independent predictor of unfavorable outcome.

Conclusions:

At time of admission, presence of hypertension, diabetes mellitus, history of alcohol consumption, and poor grades of HHS and WFNS scale are predictors of poor outcome of angio-negative SAH.

Short- and Long-Term Effects of Rehabilitation after Perimesencephalic Subarachnoid Hemorrhage

In about 25% of patients with spontaneous subarachnoid hemorrhage (SAH), a bleeding source cannot be identified during radiological diagnostics. Generally, the outcome of perimesencephalic or prepontine (PM) SAH is known to be significantly better than after non-PM SAH. Data about long-term follow-up concerning physical and mental health are scarce, so this study is reports on long-term results. We measured the influence of PM SAH on a quality-of-life modified Rankin (mRs) scale after six months. For long-term follow-up, a SF-36 questionnaire was used. Questionnaires were sent out between 18 and 168 months after ictus. In 37 patients, a long-term follow-up was available (up to 14 years after SAH). Data detected with the SF-36 questionnaire are compared to reference applicability to the standard population. In total, 37 patients were included for further analysis and divided in 2 subgroups; 13 patients (35%) received subsequent rehabilitation after clinical stay and 24 (65%) did not. In the short-term outcome, a significant improvement from discharge until follow-up was identified in patients with subsequent rehabilitation, but not in the matched pair group without rehabilitation. When PM SAH was compared to the standard population, a reduction in quality of life was identified in physical items (role limitations because of physical health problems, physical functioning) as well as in psychological items (role limitations because of emotional problems). Subsequent rehabilitation on PM SAH patients probably leads to an increase in independence and better mRs. While better mRs was shown at discharge in patients without subsequent rehabilitation, the mRs of rehabilitants was nearly identical after rehabilitation. Patients with good mRs also reached high levels of health-related quality of life (HRQoL) without rehabilitation. Thus, subsequent rehabilitation needs to be encouraged on an individual basis. Indication criteria for subsequent rehabilitation should be defined in further studies to improve patient treatment and efficiency in health care.

Baseline characteristics and outcome for aneurysmal versus non-aneurysmal subarachnoid hemorrhage: a prospective cohort study

This study aims to investigate the characteristics of patients with mild aneurysmal and non-aneurysmal perimesencephalic and non-perimesencephalic subarachnoid hemorrhage (aSAH, pmSAH, npmSAH) with emphasis on admission biomarkers, clinical course, and outcome. A prospective cohort of 115 patients with aSAH (Hunt and Hess 1–3) and of 35 patients without aneurysms (16 pmSAH and 19 npmSAH) admitted between January 2014 and January 2020 was included. Demographic data, blood samples on admission, complications (hydrocephalus, shunt dependency, delayed cerebral ischemia DCI, DCI-related infarction, and mortality), and outcome after 6 months were analyzed. Demographic data was comparable between all groups except for age (aSAH 55 [48–65] vs. npmSAH 60 [56–68] vs. pmSAH 52 [42–60], p = 0.032) and loss of consciousness (33% vs. 0% vs. 0%, p = 0.0004). Admission biomarkers showed poorer renal function and highest glucose levels for npmSAH patients. Complication rate in npmSAH was high and comparable to that of aSAH patients (hydrocephalus, shunt dependency, DCI, DCI-related infarction, mortality), but nearly absent in patients with pmSAH. Favorable outcome after 6 months was seen in 92.9% of pmSAH, 83.3% of npmSAH, and 62.7% of aSAH (p = 0.0264). In this prospective cohort of SAH patients, npmSAH was associated with a complicated clinical course, comparable to that of patients with aSAH. In contrast, such complications were nearly absent in pmSAH patients, suggesting fundamental differences in the pathophysiology of patients with different types of non-aneurysmal hemorrhage. Our findings underline the importance for a precise terminology according the hemorrhage etiology as a basis for more vigilant management of npmSAH patients. NCT02142166, 05/20/2014, retrospectively registered.

Long-term global and focal cerebral atrophy in perimesencephalic subarachnoid hemorrhage-a case-control study

PURPOSE

Non-aneurysmal perimesencephalic subarachnoid hemorrhage (PmSAH) represents 6.8% of spontaneous subarachnoid hemorrhage, and usually has a benign clinical course. However, patients might have early cerebral ischemic lesions and long-term neurocognitive complaints. Cerebral atrophy has been described in patients after aneurysmal SAH, but not in PmSAH. We aimed to investigate if PmSAH associates with increased brain volume loss.

METHODS

In this prospective study, we included consecutive patients with PmSAH that performed MR in the first 10 days after hemorrhage, and follow-up MR 6-7 years later. Automated volumetric measurements of intracranial, white matter, gray matter, whole brain, lateral ventricles, hippocampus, and amygdala volumes were performed. Volumes were compared to a normal population, matched for age.

RESULTS

Eight patients with PmSAH were included, with a mean age of 51.5 (SE 3.6) at baseline. The control group included 22 patients with a mean age of 56.3 (SE 2.0). A relative reduction of all volumes was found in both groups; however, PmSAH patients had significant reductions in intracranial, white and gray matter, whole brain, and hippocampal volumes when compared to controls. These changes had a higher magnitude in whole brain volume, with a significant absolute decrease of 6.5% in PmSAH patients (versus 1.9% in controls), and a trend for an increase in lateral ventricle volume (absolute 21.3% increase, versus 3.9% in controls).

CONCLUSION

Our cohort of PmSAH patients showed significant long-term parenchymal atrophy, and higher global and focal parenchymal volume loss rates when compared to a non-SAH population.

Brain tissue oxygenation guided therapy and outcome in non-traumatic subarachnoid hemorrhage

Brain hypoxia can occur after non-traumatic subarachnoid hemorrhage (SAH), even when levels of intracranial pressure (ICP) remain normal. Brain tissue oxygenation (PbtO₂) can be measured as a part of a neurological multimodal neuromonitoring. Low PbtO₂ has been associated with poor neurologic recovery. There is scarce data on the impact of PbtO₂ guided-therapy on patients’ outcome. This single-center cohort study (June 2014–March 2020) included all patients admitted to the ICU after SAH who required multimodal monitoring. Patients with imminent brain death were excluded. Our primary goal was to assess the impact of PbtO₂-guided therapy on neurological outcome. Secondary outcome included the association of brain hypoxia with outcome. Of the 163 patients that underwent ICP monitoring, 62 were monitored with PbtO₂ and 54 (87%) had at least one episode of brain hypoxia. In patients that required treatment based on neuromonitoring strategies, PbtO₂-guided therapy (OR 0.33 [CI 95% 0.12–0.89]) compared to ICP-guided therapy had a protective effect on neurological outcome at 6 months. In this cohort of SAH patients, PbtO₂-guided therapy might be associated with improved long-term neurological outcome, only when compared to ICP-guided therapy.

Familial Predisposition and Differences in Radiographic Patterns in Spontaneous Nonaneurysmal Subarachnoid Hemorrhage

BACKGROUND

Subarachnoid hemorrhage (SAH) from an intracranial aneurysmal rupture is the most common nontraumatic etiology for SAH, but up to 15% of patients with SAH have no identifiable source.

OBJECTIVE

To assess familial predisposition to spontaneous nonaneurysmal SAH (naSAH) and to evaluate whether family history affects the severity of presentation and prognosis of this condition.

METHODS

We conducted a retrospective analysis of all spontaneous SAH with negative digital subtraction angiography from 2004 to 2018. Patients were divided into 2 groups: patients with first- or second-degree relatives with intracranial aneurysms and patients with no family history. Univariate and multivariate regression analyses were used to study patient presentation, radiographic patterns of hemorrhage, and clinical outcome.

RESULTS

A total of 100 patients met the inclusion criteria. There were no individuals with family history of naSAH. A total of 15 patients (15%) had at least one family member with an intracranial aneurysm, of which 12 (12%) presented as SAH. Patients without family history had a higher percentage of perimesencephalic presentation, whereas those with family history had a higher percentage of nonperimesencephalic SAH presentation (47% vs 13%, odds ratio [OR] 0.17 [95% CI 0.04, 0.81]).

CONCLUSION

We found a high rate of family history of intracranial aneurysms in patients who presented with naSAH. Although there was no difference in clinical outcome in patients with and without family history, there appears to be a higher percentage of nonperimesencephalic radiographic patterns of SAH in those with family history, suggesting possible different etiologies of these hemorrhages.

Predictive Relevance of Early Temperature Elevation on the Risk of Delayed Cerebral Ischemia Development Following Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Fever in aneurysmal subarachnoid hemorrhage (aSAH) has been associated with delayed cerebral ischemia (DCI), but its relevance in risk stratification has not been explored. This study investigated whether early temperature elevation following aSAH predicts impending clinical deterioration caused by DCI.

METHODS

Relevant cases were identified from a prospectively maintained database for consecutive patients with aSAH treated at our center between July 2015 and January 2020. Temperature readings obtained every 2 hours for individual patients from admission through day 14 were recorded and analyzed. Demographic, clinical, treatment, and angiographic data were extracted from the electronic medical record. The primary end point was the occurrence of DCI (clinical and radiographic vasospasm). Multivariate logistic regression analyses were performed to account for patient age, smoking status, and VASOGRADE classification.

RESULTS

The study included 175 patients (124 women) with aSAH. The median age at diagnosis was 55.4 years (range, 20.5-87.2 years). Clinical DCI occurred in 58 patients; 2 (1.1%) responded to hemodynamic augmentation, and 56 (32.0%) required intra-arterial therapy. Temperature graphs showed a marked divergence on day 4 between clinical DCI and non-DCI groups (1.12°C ± 0.15°C and 0.76°C ± 0.08°C, respectively, P = 0.007). Patients with temperature elevation ≥2.5°C on day 4 or 5 compared with their admission temperature were more likely to clinically deteriorate owing to DCI (odds ratio 4.55, 95% confidence interval 1.31-15.77, P = 0.017).

CONCLUSIONS

Temperature elevation of ≥2.5°C on day 4 or 5 compared with baseline suggests a greater risk of clinical deterioration owing to DCI.

Nontraumatic Nonaneurysmal Subarachnoid Hemorrhage: Risk Factors, Complications, and Clinical Outcomes

Background The present study aimed to investigate the risk factors, complications, and clinical outcomes of patients with nontraumatic, nonaneurysmal subarachnoid hemorrhage (NNSAH).

Methods We retrospectively evaluated 78 consecutive patients with NNSAH admitted to our center between April 2009 and April 2019. Patients were divided into two groups based on the distribution of blood in the CT scan, perimesencephalic subarachnoid hemorrhage ( PM-SAH) and nonperimesencephalic subarachnoid hemorrhage (nPM-SAH) groups. The outcome was assessed according to the Glasgow outcome scale (GOS). The demographic data and clinical records including age, sex, smoking history, hypertension, diabetes, history of anticoagulant medication, Glasgow coma score (GCS), Hunt–Hess (HH) grades, and in-hospital complications and clinical outcomes were retrospectively reviewed and compared between the two groups.

Results There were 45 patients (57.69%) in the PM-SAH group and 33 cases (42.30%) in the nPM-SAH group with the mean age of 53.98 ± 7.7 years. There were no significant differences between the two groups based on age, sex, smoking history, diabetes, hypertension, anticoagulation medication history, and HH grade at admission. The nPM-SAH group was significantly associated with a higher incidence of radiological and clinical vasospasm (p < 0.05). Moreover, the need for external ventricular drainage (EVD) placement because of the development of hydrocephalus was significantly higher in the nPM group (p < 0.05). Patients with PM-SAH had better clinical outcomes than those with nPM-SAH (p = 0.037).

Conclusions Our results showed that patients with nonaneurysmal subarachnoid hemorrhage (NSAH) had favorable clinical outcomes. The PM group had better clinical outcomes and lower complication rates in comparison with the nPM group. Repeated digital subtraction angiography (DSA) examinations are strongly recommended for patients with nPM-SAH.

Are modified Fisher Scale and bleeding pattern helpful predictors of neurological complications in non-aneurysmal subarachnoid hemorrhage?

PURPOSE

Non-aneurysmal subarachnoid hemorrhage (NA-SAH) is a clinical-radiological entity with a different prognosis than aneurysmal SAH (A-SAH). The purpose of this study is to assess the predictive value of the modified Fisher Scale (mFS) for neurological complications in patients with this diagnosis.

METHODS

We recruited patients admitted at our hospital services between 2009 and 2017 who were diagnosed with spontaneous SAH, with either perimesencephalic (PM-SAH) or diffuse pattern (D-SAH), an initial negative angio-CT, and at least one digital subtraction angiography of brain vessels discarding underlying brain aneurysms or other vascular malformations.

RESULTS

The retrospective observational study included 116 patients. The mean age was 54.4, and the sample included predominantly male subjects (62.9%). Hunt and Hess (HH) scores on admission ranged from 3 to 5 in 18.1% of patients. The prevalence of hydrocephalus requiring ventricular drainage was 18.1%. The prevalence of symptomatic vasospasm was 4.3%. A modified Rankin Scale (mRS) 0-2 at discharge was found in 95.6%. In a multivariate logistic regression for the presence of neurological complications including age, sex, admission HH 3-5 compared with < 3, mFS 4 compared with mFS < 4, D-SAH compared with PM-SAH, and mRS score at discharge of 0-2 compared with > 2, the only significant predictors were mFS 4 compared with mFS < 4 (OR 4.47 (95% CI 1.21, 16.66) p value = 0.03) and D-SAH compared with PM-SAH (OR 7.10 (95% CI 1.24, 40.8) p value = 0.03).

CONCLUSION

In patients with NA-SAH, a mFS score of 4 and/or a D-SAH bleeding pattern in non-contrast cranial CT on admission predicted the development of relevant neurological complications.

Seizure incidence of angiogram-negative subarachnoid hemorrhage: An updated meta-analysis

BACKGROUND

To provide updated information on seizure events and patterns in patients with angiogram-negative subarachnoid hemorrhage based on the initial hemorrhage patterns: perimesencephalic subarachnoid hemorrhage (PMH) vs non-PMH.

METHODS

A review of online database literature from January 1990 to November 2017 was systematically performed. In case of heterogeneity <50%, a fixed effect model was used. Publication bias was determined using Begg funnel plot and the trim-and-fill method.

RESULTS

A total of 9 studies with 645 patients were included for final analysis after excluding one study without any seizure within either cohort. PMH patients had lower seizure rates (odds ratio, 0.393; 95% CI, 0.158-0.978) compared with non-PMH patients. The funnel plot showed a relatively asymmetric pattern, suggesting possible publication bias. After correction of the forest plot, the adjusted odds ratio was 0.362 (95% CI, 0.148-0.886), indicating significant relationships between PMH and lower incidence of seizure.

CONCLUSION

PMH is associated with lower seizure risk than non-PMH. However, possible publication bias could be a concern to the interpretation. Additional meta-analyses based on individual patient data from prospective large-scale studies are necessary.

Ten Years' Experiences in the Treatment of Nonaneurysmal Subarachnoid Hemorrhage: A Retrospective Analysis of Outcome Parameters in a Single-Center Study

Objectives:

Subarachnoid hemorrhage (SAH) with negative angiographic findings has a heterogeneous nature with variations in clinical course and outcome as compared to the aneurysmal SAH. It makes up to 15% of the spontaneous SAH and is characterized by milder clinical presentation. The purpose of this study was the analyses of risk factors, clinical observations, radiologic characteristics, and outcome in patients with nonaneurysmal SAH (NA-SAH).

Patients and Methods:

In a retrospective design, 77 consecutive patients with NA-SAH were recruited from May 2008, to October 2018. All patients underwent conventional cerebral angiography. We stratified patients into two groups based on the distribution of blood on their CT scan into perimesencephalic (PM) and non-PM (NPM) SAH. We performed the Outcome using Glasgow Coma Scale (GCS) and modified Rankin scale (favorable mRS 0–2 vs. unfavorable mRS 3–6). Data were analyzed using IBM^® SPSS^® Statistics V22.0.

Results:

The mean age at presentation was 48.5 ± 8.4 years with male predominance (71.4%). About 76.7% of the patients had headache and vomiting, most of the patients (75.3%) presented with GCS 15 at initial clinical presentation (61.03%) had NPM versus (38.96%) with PM characters in computed tomography scans. Fourteen (17.9%) patients developed hydrocephalus and 12 (15.3%) needed external ventricular drain placement, while none of the patients needed permanent shunt placement. However, all patients had a favorable clinical and functional outcome at discharge and at late follow-up (up to 3 months).

Conclusions:

NA-SAH does not affect the short- and long-term prognosis. In our results, the pattern of bleeding affects the initial presentation, clinical course, and complications. The clinical and functional outcomes in the majority of our patients were comparable in both groups with good prognosis. Hypertension, smoking, and elevated venous pressure, such as a history of deep venous thrombosis and asthma might be considered as a risk factor.

Spontaneous Subarachnoid Hemorrhage in a Patient with a Co-Existent Posterior Communicating Artery Aneurysm and Cervical Spine Aneurysm Associated with Ventral Arterio-Venous Fistula

Severe spontaneous subarachnoid hemorrhage (SAH) is predominantly caused by aneurysm rupture, with non-aneurysmal vascular lesions representing only a minority of possible causes. We present the case of a 58-year old lady with a coincidental posterior communicating artery (PCom) aneurysm and a high cervical spine arterio-venous fistula associated with a small ruptured aneurysm. After the emergency clipping of the PCom aneurysm, additional diagnostic procedures—repeated digital subtraction angiography and spinal magnetic resonance imaging, revealed the actual cause of the SAH, a type-A ventral intradural fistula at cervical level C2/3. The fistula was treated micro surgically via a ventral approach using C3 somatectomy and C2-4 stabilization after the initial failure of endovascular therapy. Furthermore, the patient was treated for complications associated with severe SAH, including acute hydrocephalus and meningitis. In cases where the SAH pattern and perioperative findings do not suggest an intracranial aneurysm as the source of SAH, further diagnostic investigation is warranted to discover the real cause. Patients with severe non-aneurysmal SAH require a similar algorithm in diagnosing the cause of the hemorrhage as well as complex conditions such as ruptured aneurysms.

Descriptive Study of Aneurysmal and Nonaneurysmal Subarachnoid Hemorrhage and the Role of Confirmative Digital Subtraction Angiography in Patients with Nonaneurysmal Subarachnoid in Puerto Rico

BACKGROUND

Cerebrovascular disease is the fifth cause of mortality in Puerto Rico. There is no descriptive study for the presentation of spontaneous subarachnoid hemorrhage (SAH) in our institution. Therefore, our primary aim was to perform a retrospective analysis of adult patients with spontaneous SAH and assess the need for digital subtraction angiography (DSA) after initially aneurysm-negative computed tomography angiography (CTA) in nonaneurysmal SAH, specifically perimesencephalic SAH (PM-SAH).

METHODS

Medical records of 324 adult patients with aneurysmal and nonaneurysmal SAH treated at the Puerto Rico Medical Center from 2015 to 2018 were retrospectively analyzed. Demographics, past medical history, clinical characteristics, and imaging information were extracted.

RESULTS

Acute hydrocephalus, mortality at 30 days, prevalence of diffuse SAH pattern, and Fisher and World Federation of Neurosurgical Societies grades >2 on initial examination were higher in the aneurysmal SAH subgroup. Patients with nonaneurysmal SAH had a significantly higher prevalence of chronic kidney disease and diabetes mellitus. Of the patients with nonaneurysmal PM-SAH with initial aneurysm-negative CTA, 100% were subsequently confirmed by DSA.

CONCLUSIONS

Patients in the aneurysmal SAH subgroup correlated with an increased disease burden. Furthermore, this study shows that in our population, patients with nonaneurysmal PM-SAH with a low Fisher and World Federation of Neurosurgical Societies grade and with comorbid diabetes mellitus and chronic kidney disease may not need DSA after a negative initial CTA result.

Subarachnoid haemorrhage with negative initial neurovascular imaging: a systematic review and meta-analysis

Background

In patients with spontaneous subarachnoid haemorrhage (SAH), a vascular cause for the bleed is not always found on initial investigations. This study aimed to systematically evaluate the delayed investigation strategies and clinical outcomes in these cases, often described as “non-aneurysmal” SAH (naSAH).

Methods

A systematic review was performed in concordance with the PRISMA checklist. Pooled proportions of primary outcome measures were estimated using a random-effects model.

Results

Fifty-eight studies were included (4473 patients). The cohort was split into perimesencephalic naSAH (PnaSAH) (49.9%), non-PnaSAH (44.7%) and radiologically negative SAH identified on lumbar puncture (5.4%). The commonest initial vascular imaging modality was digital subtraction angiography. A vascular abnormality was identified during delayed investigation in 3.9% [95% CI 1.9–6.6]. There was no uniform strategy for the timing or modality of delayed investigations. The pooled proportion of a favourable modified Rankin scale outcome (0–2) at 3–6 months following diagnosis was 92.0% [95% CI 86.0–96.5]. Complications included re-bleeding (3.1% [95% CI 1.5–5.2]), hydrocephalus (16.0% [95% CI 11.2–21.4]), vasospasm (9.6% [95% CI 6.5–13.3]) and seizure (3.5% [95% CI 1.7–5.8]). Stratified by bleeding pattern, we demonstrate a higher rate of delayed diagnoses (13.6% [95% CI 7.4–21.3]), lower proportion of favourable functional outcome (87.2% [95% CI 80.1–92.9]) and higher risk of complications for non-PnaSAH patients.

Conclusion

This study highlights the heterogeneity in delayed investigations and outcomes for patients with naSAH, which may be influenced by the initial pattern of bleeding. Further multi-centre prospective studies are required to clarify optimal tailored management strategies for this heterogeneous group of patients.

Electronic supplementary material

The online version of this article (10.1007/s00701-019-04025-w) contains supplementary material, which is available to authorized users.

Return to work after subarachnoid hemorrhage: The influence of cognitive deficits

INTRODUCTION

Cognitive deficits are frequently found after subarachnoid hemorrhage (SAH), but their influence on return to work is largely unknown. To improve identification of those patients at-risk for long-term return to work problems, we aimed to examine the value of cognitive deficits in the prediction of long-term return to work after subarachnoid hemorrhage.

METHODS

SAH patients (N = 71) who were employed before SAH and were able to undergo neuropsychological assessment, were included. Demographic characteristics and acute SAH-related variables (SAH-type and external cerebrospinal fluid drainage) were taken into account. Neuropsychological tests for memory, speed, attention, executive function, and emotion recognition and a questionnaire for executive functions were used. Return to work was assessed using the Role Resumption List.

RESULTS

Results showed that patients with incomplete return to work had significantly lower scores on neuropsychological measures for complex attention and executive functions (p < 0.05) compared to patients with complete return to work. Return to work could not be significantly predicted using only demographic characteristics and acute SAH-related variables, but adding measures of complex attention and executive functions resulted in a prognostic model that could reliably distinguish between complete and incomplete return to work. Statistically significant predictors in the final model were cerebrospinal fluid drainage and scores on a questionnaire for executive functions: patients with cerebrospinal fluid drainage and higher scores on the a questionnaire for executive functions were less likely to return to work.

DISCUSSION

Together, these findings show that neuropsychological measures, especially for complex attention and executive functions, have added value to acute SAH-related and demographic variables in the prediction of long-term return to work after SAH.

Outcomes of microsurgical clipping vs coil embolization for ruptured aneurysmal subarachnoid hemorrhage: A multicenter real-world analysis of 583 patients in China

Aneurysmal subarachnoid hemorrhage (SAH) is a complex neurovascular syndrome with high disability and mortality. SAH patients may be managed with surgical clipping or coil embolization. In this study, we provided a real-world analysis of the outcome and prognostic factors of aneurysmal SAH in patients treated with coil embolization or microsurgical clipping.We retrospectively analyzed the medical records of aneurysmal SAH patients (n = 583) who underwent treatment at the First Hospital and the Second Hospital of Hebei Medical University, and Tangshan Worker's Hospital in China. All patients were evaluated by a combined neurosurgery and interventional neuroradiology team. Microsurgical aneurysmal clipping was performed using the skull base approach, while coil embolization was performed with bare platinum coils (with or without balloon assistance). The primary outcome was the Glasgow Outcome Scale (GOS) score at discharge.A total of 583 patients were included in this study, of which 397 (68.1%) of them underwent clipping and 186 (31.9%) received coil embolization. The patient cohort consisted of both poor grade and good grade aneurysmal SAH: 441 (75.6%) patients had good-grade (Hunt and Hess grade II or III) and 142 (24.4%) had poor grade (Hunt and Hess grade IV or V). Overall, 123 (21%) patients had unfavorable neurologic outcome (GOS score 1-3) and 460 (78.9%) patients had favorable neurologic outcome (GOS score 4 or 5). The mean GOS score at discharge was comparable for patients who underwent clipping and those received coil embolization (P > .05). Multivariate analysis showed that clipping only [OR (95%CI): 0.03 (0.01, 0.36); P = .000] and clipping with CSF drainage [OR (95%CI): 0.41 (0.18, 0.89); P = .001] were independent factors of a favorable outcome in patients with aneurysmal SAH. Coil embolization with hematoma removal [OR (95%CI): 0.03 (0.01, 0.36); P = .000] was also an independent determinant of a favorable outcome. High baseline Fisher grades were associated with significantly increased risk of an unfavorable outcome [OR (95%CI): 2.08 (1.30, 3.33); P = .002].Our findings suggested that both coil embolization and microsurgical clipping are viable treatment options for aneurysmal SAH patients. Procedures, such as CSF drainage and hematoma removal, performed in parallel with coil embolization and chipping should be considered when treating individual patients.

Comparing Outcomes of Patients With Idiopathic Subarachnoid Hemorrhage by Stratifying Perimesencephalic Bleeding Patterns

BACKGROUND

To determine the clinical outcomes of perimesencephalic subarachnoid hemorrhages based on the computed tomography (CT) bleeding patterns.

METHODS

This retrospective cohort study included: (1) patients (≥18 years) admitted to a comprehensive stroke center (January 2015-May 2018), (2) with angiography-negative, nontraumatic subarachnoid hemorrhage in a perimesencephalic or diffuse bleeding pattern, and (3) had CT imaging performed in ≤ 72 hours of symptom onset. Patients were stratified by location of bleeding on CT: Peri-1: focal prepontine hemorrhage; Peri-2: prepontine with suprasellar cistern +/- intraventricular extension; and diffuse.

RESULTS

Of the 39 patients included, 13 were Peri-1, 11 were Peri-2, and 15 were diffuse. The majority were male (n = 26), with a mean (standard deviation) age of 55.3 (11.3) years, who often presented with headache (n = 37) and nausea (n = 28). Overall, patients in Peri-1 were significantly less likely to have hydrocephalus compared to Peri-2 and dSAH (P= .003), and 4 patients required an external ventricular drain. Five patients developed symptomatic vasospasm. Patients in Peri-1, compared to Peri-2 and diffuse, had a significantly shorter median neuro critical care unit length of stay (LOS) and hospital LOS. Most patients (n = 35) had a discharge modified Rankin Score between 0 and 2 with no significant differences found between groups.

CONCLUSION

These data suggest that patients with the best clinical course were those in Peri-1, followed by Peri-2, and then diffuse. Because these patients often present with similar clinical signs, stratifying by hemorrhage pattern may help clinicians predict which patients with perimesencephalic subarachnoid hemorrhage develop complications.

CT angiogram negative perimesencephalic subarachnoid hemorrhage: is a subsequent DSA necessary? A systematic review

Background

Perimesencephalic subarachnoid hemorrhage (PMSAH) is a benign subtype with distinct clinical-radiologic features. Digital subtraction angiography (DSA) remains the gold standard investigation for exclusion of a macrovascular cause, although increasingly more clinicians rely solely on CT angiography (CTA). The primary aim of this systematic review was to evaluate the current literature regarding the negative predictive value of CTA.

Methods

A systematic search in concordance with the PRISMA checklist was performed for studies published between 2000 and 2018. Studies with ≥10 adult patients diagnosed on a non-contrast brain CT with a PMSAH, who underwent a negative CTA and were subsequently subject to a DSA, were included. Simple pooled analysis was performed to inform the negative predictive value (95% CI) of CTA and the risk of DSA- and CTA-related complications.

Results

Eighteen studies (669 patients) were included. All patients were subject to at least one DSA, the first one mostly performed within 24 hours of CTA (68.6%). 144 patients (21.5%) underwent a second DSA and a third repeat DSA was performed in one patient. The overall negative predictive value of CTA was 99.0% (95% CI 97.8% to 99.5%). The risk of complications following DSA and CTA were 1.35% (3/222) and 0% (0/41), respectively.

Conclusions

Undertaking a DSA after a negative CTA may not add any further diagnostic value in patients with PMSAH and may lead to net harm. This observation needs to be validated in a large-scale prospective multicenter study with complete case ascertainment and robust data on CTA and DSA complications.

Recurrent Bleeding After Perimesencephalic Hemorrhage: Case Report and Review of the Literature

BACKGROUND

Perimesencephalic hemorrhage (PMH), a subtype of nonaneurysmal subarachnoid hemorrhage, is characterized by a typical pattern of localized hemorrhage on head computed tomography. PMH is usually associated with a benign clinical course, and a lower incidence of complications such as vasospasm and rebleeding.

CASE DESCRIPTION

We present the cases of a man aged 28 years and a woman aged 21 years with no relevant medical history who experienced recurrent, spontaneous episodes of PMH within the course of 7 days and 29 months. No precipitating causes were identified.

CONCLUSIONS

There are only a couple of case reports of recurrent PMH, some of which were defined questionably. We review the reported cases and discuss the possible causes and long-term outcomes. Neurointerventionalists and neurosurgeons should be aware that the risk of recurrent hemorrhage of PMH does exist, although it is rather low. Even after early or late rebleeding, prognosis of PMH is excellent.

Mortality and functional outcomes after a spontaneous subarachnoid haemorrhage: A retrospective multicentre cross-sectional study in Kenya

INTRODUCTION

Despite a reduction in poor outcomes in recent decades, spontaneous subarachnoid haemorrhage (SAH) remains associated with severe disability and high mortality rates. The exact extent of these outcomes is however unknown in Africa. This study aimed to determine the mortality and functional outcomes of patients with SAH in Kenya.

METHODS

We conducted a retrospective multicentre cross-sectional study involving patients admitted with SAH to three referral hospitals in Nairobi. All patients with a confirmed (primary) discharge diagnosis of first-time SAH between January 2009 and November 2017 were included (n = 158). Patients who had prior head trauma or cerebrovascular disease (n = 53) were excluded. Telephone interviews were conducted with surviving patients or their next of kin to assess out-of-hospital outcomes (including functional outcomes) based on modified Rankin Scale (mRS) scores. Chi-square and Fisher's exact tests were used to assess associations between mortality and functional outcomes and sample characteristics.

RESULTS

Of the 158 patients sampled, 38 (24.1%) died in hospital and 42 (26.6%) died within 1 month. In total, 87 patients were discharged home and followed-up in this study, of which 72 reported favourable functional outcomes (mRS ≤2). This represented 45.6% of all patients who presented alive, pointing to high numbers of unfavourable outcomes post SAH in Kenya.

CONCLUSIONS

Mortality following SAH remains high in Kenya. Patients who survive the initial ictus tend to do well after treatment, despite resource constraints.

LIMITATIONS

The study findings should be interpreted with caution because of unavoidable limitations in the primary data. These include its retrospective nature, the high number of patients lost to follow up, missing records and diagnoses, and/or possible miscoding of cases.

A Review of the Management of Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Despite decades of research, cerebral vasospasm (CV) continues to account for high morbidity and mortality in patients who survive their initial aneurysmal subarachnoid hemorrhage.

OBJECTIVE

To define the scope of the problem and review key treatment strategies that have shaped the way CV is managed in the contemporary era.

METHODS

A literature search was performed of CV management after aneurysmal subarachnoid hemorrhage.

RESULTS

Recent advances in neuroimaging have led to improved detection of vasospasm, but established treatment guidelines including hemodynamic augmentation and interventional procedures remain highly variable among neurosurgical centers. Experimental research in subarachnoid hemorrhage continues to identify novel targets for therapy.

CONCLUSIONS

Proactive and preventive strategies such as oral nimodipine and endovascular rescue therapies can reduce the morbidity and mortality associated with CV.

The Acute Phase of Experimental Subarachnoid Hemorrhage: Intracranial Pressure Dynamics and Their Effect on Cerebral Blood Flow and Autoregulation

Clinical presentation and neurological outcome in subarachnoid hemorrhage (SAH) is highly variable. Aneurysmal SAH (aSAH) is hallmarked by sudden increase of intracranial pressure (ICP) and acute hypoperfusion contributing to early brain injury (EBI) and worse outcome, while milder or non-aneurysmal SAH with comparable amount of blood are associated with better neurological outcome, possibly due to less dramatic changes in ICP. Acute pressure dynamics may therefore be an important pathophysiological aspect determining neurological complications and outcome. We investigated the influence of ICP variability on acute changes after SAH by modulating injection velocity and composition in an experimental model of SAH. Five hundred microliters of arterial blood (AB) or normal saline (NS) were injected intracisternally over 1 (AB₁, NS₁), 10 (AB_10, NS₁₀), or 30 min (AB₃₀) with monitoring for 6 h (n = 68). Rapid blood injection resulted in highest ICP peaks (AB₁ median 142.7 mmHg [1.Q 116.7-3.Q 230.6], AB₃₀ 33.42 mmHg [18.8-38.3], p < 0.001) and most severe hypoperfusion (AB₁ 16.6% [11.3-30.6], AB₃₀ 44.2% [34.8-59.8]; p < 0.05). However, after 30 min, all blood groups showed comparable ICP elevation and prolonged hypoperfusion. Cerebral autoregulation was disrupted initially due to the immediate ICP increase in all groups except NS₁₀; only AB₁, however, resulted in sustained impairment of autoregulation, as well as early neuronal cell loss. Rapidity and composition of hemorrhage resulted in characteristic hyperacute hemodynamic changes, with comparable hypoperfusion despite different ICP ranges. Only rapid ICP increase was associated with pronounced and early, but sustained disruption of cerebral autoregulation, possibly contributing to EBI.

Analysis of biochemical laboratory values to determine etiology and prognosis in patients with subarachnoid hemorrhage: a clinical study

OBJECTIVES

The aim of this study was to establish prognostic and predictive markers in patients with subarachnoid hemorrhage (SAH) using simple laboratory methods.

METHODS

A retrospective examination was made of patients with SAH diagnosed secondary to isolated head trauma, isolated anterior communicating artery aneurysm rupture, and angiography-negative SAH. Age, gender, Glasgow Coma Scale (GCS) scores, and Fisher's grade scores, Glasgow Outcome Scale (GOS) scores, leukocyte count, neutrophil count, lymphocyte count, platelet count, neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio results (PLR) were evaluated.

RESULTS

NLR and PLR values, which were similar in patients with spontaneous SAH, were significantly high in patients with traumatic SAH. NLR and PLR values could be 80% sensitive and 75% specific for distinguishing traumatic SAH from spontaneous SAH. Eosinophil count was lower in patients with angiography-negative SAH and patients with aneurysmal SAH than in patients with traumatic SAH. Initially measured GCS score, Fisher's grade score, eosinophil, neutrophil and lymphocyte counts could be prognostic in all patients with SAH. Moreover, it was concluded that the initially measured number of eosinophils might be directly related to patient prognosis. The eosinophil count was generally found to be high in traumatic SAH patients and it was observed that this parameter could be predictive for these patients. Lymphocyte count and NLR values could be prognostic markers in patients with angiography-negative SAH.

CONCLUSION

NLR, PLR and eosinophil count values could be predictive for etiological factors (traumatic SAH or spontaneous SAH) of patients who were admitted unconscious to the emergency room with SAH detected on radiological imaging.

The Incidence of Hydrocephalus and Shunting in Patients with Angiogram-Negative Subarachnoid Hemorrhage: An Updated Meta-Analysis

OBJECTIVE

To evaluate the incidence of hydrocephalus and implanted shunts in angiogram-negative subarachnoid hemorrhage (SAH) according to hemorrhage patterns: perimesencephalic SAH (PMH) versus non-PMH.

METHODS

The online database literature from January 1990 to November 2017 was systematically reviewed. A fixed-effect model was used when heterogeneity was <50%. A Begg funnel plot was used to assess publication bias. An additional trim and fill method was used to estimate the number of missing studies. A subgroup analysis with studies, which defined angiogram-negative SAH using repeated angiography or computed tomography angiography, was further performed.

RESULTS

A total of 28 articles including 2577 patients were enrolled. Patients with PMH showed a significantly decreased incidence of hydrocephalus (odds ratio [OR], 0.269; 95% confidence interval [CI], 0.208-0.348) and shunts (OR, 0.263; 95% CI, 0.169-0.411) than did patients without PMH. A subgroup analysis of 7 studies with 675 patients showed less hydrocephalus in patients with PMH than in patients without PMH (OR, 0.358; 95% CI, 0.161-0.793), with possible publication bias. Shunt procedures were marginally less common in patients with PMH compared with those patients without PMH (OR, 0.490; 95% CI, 0.236-1.018) with possible publication bias. After correction of the forest plot, the adjusted OR was 0.617 (95% CI, 0.251-1.513) for hydrocephalus and 0.618 (95% CI, 0.310-1.232) for shunts, suggesting no significant relationships between PMH and the risk of hydrocephalus or shunting.

CONCLUSIONS

Hydrocephalus and shunts were more evident in non-PMH than PMH. However, subgroup analyses did not show significant associations between PMH and lower risks of these events after correction for possible publication bias. Further meta-analyses based on individual patient data are necessary.

Delayed Cerebral Ischemia and Vasospasm After Spontaneous Angiogram-Negative Subarachnoid Hemorrhage: An Updated Meta-Analysis

OBJECTIVE

To report clinical outcomes of delayed cerebral ischemia (DCI) and vasospasm in angiogram-negative subarachnoid hemorrhage (SAH) according to hemorrhage patterns, perimesencephalic hemorrhage (PMH) and non-PMH.

METHODS

Online databases from January 1990 to December 2017 were systematically reviewed. A fixed-effects model was used to control heterogeneity. To resolve publication bias, the trim and fill method was used to estimate number of missing studies and adjusted odds ratio (OR). Subgroup analysis of data from studies that defined angiogram-negative subarachnoid hemorrhage by angiography repeated at least twice or computed tomography angiography was performed.

RESULTS

Among 24 studies including 2083 patients, 23/985 patients (2.3%) with PMH and 144/1098 patients (13.1%) with non-PMH had DCI, indicating that patients with PMH experienced significantly lower DCI than patients with non-PMH (OR = 0.219; 95% confidence interval [CI], 0.144-0.334). Regarding vasospasm, 99/773 patients (12.8%) with PMH and 231/922 patients (25.1%) with non-PMH exhibited vasospasm, indicating that patients with PMH experienced significantly lower vasospasm than patients with non-PMH (OR = 0.445; 95% CI, 0.337-0.589). Funnel plots show asymmetry indicating possible publication bias. After trimming 10 studies for DCI and 7 for vasospasm, the adjusted ORs remained significant between PMH and lower risks of DCI and vasospasm. Subgroup analysis of 789 patients in 8 studies showed a lower risk of DCI (OR = 0.268; 95% CI, 0.151-0.473) and vasospasm (OR = 0.346; 95% CI, 0.221-0.538) in patients with PMH.

CONCLUSIONS

PMH showed a significantly lower risk of DCI and vasospasm than non-PMH. Clinical outcomes of angiogram-negative subarachnoid hemorrhage, based on meta-analysis of individual patient data, need to be investigated.

Influence of ABO blood type on the outcome after non-aneurysmal subarachnoid hemorrhage

BACKGROUND

In patients with non-aneurysmal subarachnoid hemorrhage (NA-SAH), the etiology is unknown and the bleeding source remains unidentified. However, the ABO blood type system has a profound role in patient's hemostasis and thrombosis. To date, the aspect of ABO blood type in incidence, clinical course, and outcome after NA-SAH has not been investigated.

METHODS

In this retrospective analysis, 81 patients with non-traumatic and non-aneurysmal subarachnoid hemorrhage treated between 2010 and 2014 at the author's institution were included. WFNS admission status, cerebral vasospasm, delayed infarction, ventriculoperitoneal shunt necessity, the Fisher grade, and the modified Rankin Scale were analyzed for their association with ABO blood type. Four hundred seventy patients with aneurysmal subarachnoid hemorrhage served as a control group.

RESULTS

The AB blood type is more frequent in NA-SAH compared to aneurysmal patients and the German population (OR 2.45, p ≤ 0.05). Furthermore, NA-SAH with AB blood type showed a similar sequelae compared to aneurysmal patients in terms of shunt necessity (OR 2.00, p ≥ 0.05), cerebral vasospasm (OR 1.66, p ≥ 0.05), and delayed infarctions (OR 1.07, p ≥ 0.05).

CONCLUSION

The clinical course of NA-SAH AB blood type patients shows similar severity as of aneurysmal subarachnoid hemorrhage. Therefore, patients with AB blood type should be under intensified observation.