Prognostic value and determinants of ultraearly angiographic vasospasm after aneurysmal subarachnoid hemorrhage

Clinical Impact and Predictors of Aneurysmal Rebleeding in Poor-Grade Subarachnoid Hemorrhage: Results From the National POGASH Registry

BACKGROUND

Scarce data are available regarding rebleeding predictors in poor-grade aneurysmal subarachnoid hemorrhage (aSAH).

OBJECTIVES

To investigate predictors and clinical impact of rebleeding in a national multicentric poor-grade aSAH.

METHODS

Retrospective analysis of prospectively collected data from the multicentric Poor Grade Aneurysmal Subarachnoid Hemorrhage Study Group (POGASH) registry of consecutive patients treated from January 1, 2015, to June 30th, 2021. Grading was defined as pretreatment World Federation of Neurological Surgeons grading scale IV-V. Ultra-early vasospasm (UEV) was defined as luminal narrowing of intracranial arteries not due to intrinsic disease. Rebleeding was defined as clinical deterioration with evidence of increased hemorrhage on subsequent computed tomography scans, fresh blood from the external ventricular drain, or deterioration before neuroradiological evaluation. Outcome was assessed by the modified Rankin Scale.

RESULTS

Among 443 consecutive World Federation of Neurological Surgeons grades IV-V patients with aSAH treated within a median of 5 (IQR 4-9) hours since onset, rebleeding occurred in 78 (17.6%). UEV (adjusted odds ratio [OR] 6.8, 95% CI 3.2-14.4; P < .001) and presence of dissecting aneurysm (adjusted OR 3.5, 95% CI 1.3-9.3; P = .011) independently predicted rebleeding while history of hypertension (adjusted OR 0.4, 95% CI 0.2-0.8; P = .011) independently reduced its chances. 143 (32.3) patients died during hospitalization. Rebleeding emerged, among others, as an independent predictor of intrahospital mortality (adjusted OR 2.2, 95% CI 1.2-4.1; P = .009).

CONCLUSION

UEV and presence of dissecting aneurysms are the strongest predictors of aneurysmal rebleeding. Their presence should be carefully evaluated in the acute management of poor-grade aSAH.

Feasibility of FDCT Early Brain Parenchymal Blood Volume Maps in Predicting Short-Term Prognosis in Patients With Aneurysmal Subarachnoid Hemorrhage

Purpose

Aneurysmal subarachnoid hemorrhage (SAH) is accompanied by cerebral perfusion changes. We aimed to measure the parenchymal blood volume (PBV) maps acquired by C-arm flat-panel detector CT (FDCT) to assess the cerebral blood volume at an early stage in aneurysmal SAH and to explore the correlation with the outcomes at discharge.

Methods

Data of 66 patients with aneurysmal SAH who underwent FDCT PBV examination were retrospectively analyzed. The PBV of regions of interest, including the cortices of the bilateral frontal lobe, the parietal lobe, the occipital lobe, and the cerebral hemisphere, as well as the basal ganglia, were measured and quantitatively analyzed. The clinical and imaging data of the patients were also collected, and logistic regression analysis was performed to explore the correlation between the perfusion parameters and outcomes at discharge.

Results

The favorable and poor outcomes at discharge were found in 37 (56.06%) and 29 (43.94%) patients, respectively. The whole-brain PBV was significantly correlated with the Hunt-Hess grades (p < 0.005) and the WFNSS grades (p < 0.005). The whole-brain PBV of the poor prognosis was significantly higher than that of the favorable prognosis (35.17 ± 7.66 vs. 29.78 ± 5.54, p < 0.005). The logistic regression analysis showed that the PBV of the parietal lobe at the bleeding side (OR = 1.10, 95%CI: 1.00-1.20, p = 0.04) was an independent risk factor predicting the short-term prognosis.

Conclusions

Parenchymal blood volume (PBV) maps could reflect the cerebral blood volume throughout the brain to characterize its perfusion status at an early stage in aneurysmal SAH. It enables a one-stop imaging evaluation and treatment in the same angio-suite and may serve as a reliable technique in clinical assessment of aneurysmal SAH.

Acute paraparesis syndrome after ruptured anterior communicating artery aneurysm

Here, we describe a series of 7 patients who presented with acute paraparesis due to anterior communicating artery aneurysm rupture. This study aimed to assess the clinical and radiological factors associated with acute paraparesis syndrome caused by subarachnoid hemorrhage (SAH).Between June 2005 and December 2012, our institution consecutively treated 210 patients with anterior communicating aneurysm rupture within 24 hours after ictus. We divided the patients into 2 groups based on the presence (n = 7) and absence (n = 203) of acute paraparesis after anterior communicating aneurysm rupture.Diffusion-weighted magnetic resonance imaging revealed high intensity in the medial aspects of the bilateral frontal lobes in 3 patients. The mean third ventricular distance at the time of admission was 9.2 mm (range, 8-12.5 mm), and the mean bicaudate distance was 33.9 mm (range, 24-39 mm). There was a significant difference in the bicaudate distance (P = .001) and third ventricle distance (P = .001) between the 2 groups. Acute hydrocephalus and global cerebral edema (GCE) were confirmed radiologically in all patients in the acute paraparesis group. The presence of acute hydrocephalus (P = .001) and GCE (P = .003) were significantly different between the groups.Acute paraparesis syndrome after SAH is transient and gradually improves if the patient does not develop severe vasospasm. The present study demonstrates that acute paraparesis after SAH is associated with acute hydrocephalus and GCE.

Risk of Re-Rupture, Vasospasm, or Re-Stroke after Clipping or Coiling of Ruptured Intracranial Aneurysms: Long-Term Follow-Up with a Propensity Score-Matched, Population-Based Cohort Study

Scarce evidence is available in Asia for estimating the long-term risk and prognostic factors of major complications such as re-rupture, vasospasm, or re-stroke for patients with aneurysmal subarachnoid hemorrhage (SAH) undergoing endovascular coil embolization or surgical clipping. This is the first head-to-head propensity score-matched study in an Asian population to demonstrate that endovascular coil embolization for aneurysmal SAH treatment is riskier than surgical clipping in terms of re-rupture, vasospasm, or re-stroke. In addition, the independent poor prognostic factors of vasospasm or re-stroke were endovascular coil embolization, male sex, older age (≥65 years; the risk of vasospasm increases with age), hypertension, congestive heart failure, diabetes, previous transient ischemic attack, or stroke in aneurysmal SAH treatment. Background: To estimate the long-term complications and prognostic factors of endovascular coil embolization or surgical clipping for patients with ruptured aneurysmal subarachnoid hemorrhage (SAH). Methods: We selected patients diagnosed with aneurysmal SAH between 1 January 2011 and 31 December 2017. Propensity score matching was performed, and Cox proportional hazards model curves were used to analyze the risk of re-rupture, vasospasm, and re-stroke in patients undergoing the different treatments. Findings: Multivariate Cox regression analysis revealed that the adjusted hazard ratio (aHR) of re-rupture for endovascular coil embolization compared with surgical clipping was 1.36 (95% confidence interval [CI]: 1.17–1.57; p < 0.0001). The aHRs of the secondary endpoints of vasospasm and re-stroke (delayed cerebral ischemia) for endovascular coil embolization compared with surgical clipping were 1.14 (1.02–1.27; p = 0.0214) and 2.04 (1.83–2.29; p < 0.0001), respectively. The independent poor prognostic factors for vasospasm and re-stroke were endovascular coil embolization, male sex, older age (≥65 years; risk increases with age), hypertension, congestive heart failure, diabetes, and previous transient ischemic attack or stroke. Interpretation: Endovascular coil embolization for aneurysmal SAH carries a higher risk than surgical clipping of both short- and long-term complications including re-rupture, vasospasm, and re-stroke.

Ultra-Early Angiographic Vasospasm After Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis

OBJECTIVE

After aneurysmal subarachnoid hemorrhage (aSAH), prognosis is affected heavily by the presence of delayed cerebral ischemia (DCI). There is growing recognition of ultra-early angiographic vasospasm (UEAV) occurring within 48 hours of aSAH; however, its relationship with DCI and ultimately prognosis remains unclear.

METHODS

Various databases limited to the English language through September 2016 were searched systematically. Eligible studies were those comparing UEAV with control non-UEAV outcomes and follow-up. Two independent reviewers evaluated the quality of studies and abstracted the data, with discrepancies resolved by a third. We calculated odds ratios (ORs) and 95% confidence intervals for all outcomes by using random-effects meta-analyses and performed a heterogeneity analysis.

RESULTS

Four comparative studies were selected for analysis. Pooled analysis demonstrated that UEAV compared with no-UEAV was associated with greater proportion of rupture aneurysms sized greater than 12 mm (38.3% vs. 24.3%, P < 0.00001). A significantly greater number of patients with UEAV had ruptured MCA aneurysms compared with patients without UEAV (29.7% vs. 19.9%, P = 0.005). Compared with no-UEAV, patients with UEAV were significantly associated with symptomatic cerebral vasospasm (OR 2.07, P = 0.05) and DCI/infarction (OR 2.52, P = 0.02). A significant association also was found between UEAV and an unfavorable outcome at follow-up (OR 1.64, P = 0.03) and greater mortality (OR 2.65, P < 0.00001).

CONCLUSIONS

UEAV was significantly associated with symptomatic cerebral vasospasm, DCI/infarction, unfavorable outcome at follow-up, and greater mortality. Patients with intracerebral hematoma, intraventricular hemorrhage (Fisher Grade IV), larger ruptured aneurysms >12 mm, and an MCA location were more likely to have UEAV.

Aneurysmal Surgery in the Presence of Angiographic Vasospasm: An Outcome Assessment

Background and Purpose:

The timing of aneurysmal surgery for patients presenting within the period at risk for vasospasm (VS) is controversial. The goal of this study is to review our experience of surgically treated patients in the presence of angiographic VS.

Materials and Methods:

From 1990-2004, 894 consecutive patients presented with an aneurysmal subarachnoid hemorrhage (SAH) and were treated with a policy of early surgery. We retrospectively analyzed the patients that had pre-operative angiographic VS. In this study, symptomatic VS was diagnosed when a decreased level of consciousness and/or focal deficit occurred after SAH in the presence of angiographic VS without confounding factors. Functional outcome was assessed three months after SAH using the Glasgow Outcome Scale.

Results:

Of the 40 patients studied, 62.5% were in good clinical grade Hunt & Hess (H&H 1-2) on admission; 25%, intermediate grade (H&H 3); 12.5%, poor grade (H&H 4-5). Surgery was performed 24 hours or less after initial angiography in 87.5% of patients and less than 48 hours in 97.5%. Pre-operative symptomatic VS was diagnosed in 25%. Postoperatively, angiographic VS was documented in 87.2%. Of the 30% of patients that presented post-operative symptomatic VS, 66.7% also demonstrated pre-operative symptomatic VS. The functional outcome was favorable in 92.5% of the studied patients. Two deaths occurred in patients presenting pre-operative early radiological and symptomatic VS.

Conclusion:

Aneurysmal surgery, especially between 3-12 days following SAH, in the presence of asymptomatic pre-operative angiographic VS can be associated with a good outcome. Early surgery is not contra-indicated and might enable optimal treatment of VS.

Predictors of Delayed Cerebral Ischemia in Patients with Aneurysmal Subarachnoid Hemorrhage with Asymptomatic Angiographic Vasospasm on Admission

BACKGROUND

Risk of delayed cerebral ischemia (DCI) in patients with aneurysmal subarachnoid hemorrhage (aSAH) with asymptomatic angiographic vasospasm on admission is unclear in the literature. The goal of this study is to identify predictors of clinical DCI in this group of patients.

METHODS

An exploratory subgroup analysis was conducted in the SAHIT (Subarachnoid Hemorrhage International Trialists) data repository to identify predictors of clinical DCI in patients with good-grade aSAH (World Federation of Neurological Surgeons grade I and II) with angiographic vasospasm on admission. Predictors considered include age, sex, systolic blood pressure at presentation, World Federation of Neurological Surgeon grade, Fisher grade, aneurysm size and location, treatment modality, hydrocephalus requiring external ventricular drain insertion, and severity of vasospasm. The predictors were ranked based on dominance analysis with R² as fit statistics and assessed in a set of logistic regression analysis models.

RESULTS

Four data sets out of 16 studies in the SAHIT database were analyzed, with a total of 4125 patients. One hundred and ninety-one patients (4.6%) had asymptomatic angiographic vasospasm at admission. Of those, 78 patients (40.8%) developed clinical DCI. Univariate analysis showed significant associations between severe vasospasm on admission and development of clinical DCI (odds ratio, 9.5, 95% confidence interval, 2.07-43.50; P = 0.004). None of the studied predictors was associated with the development of clinical DCI on multivariate analysis.

CONCLUSIONS

Asymptomatic angiographic vasospasm in patients with good-grade aSAH on admission is uncommon. Further studies are needed to identify high-risk patients for the development of DCI in the context of asymptomatic early vasospasm.

Ultra-early angiographic vasospasm associated with delayed cerebral ischemia and infarction following aneurysmal subarachnoid hemorrhage

OBJECTIVE The clinical significance of cerebral ultra-early angiographic vasospasm (UEAV), defined as cerebral arterial narrowing within the first 48 hours of aneurysmal subarachnoid hemorrhage (aSAH), remains poorly characterized. The authors sought to determine its frequency, predictors, and impact on functional outcome. METHODS The authors prospectively studied UEAV in a cohort of 1286 consecutively admitted patients with aSAH between August 1996 and June 2013. Admission clinical, radiographic, and acute clinical course information was documented during patient hospitalization. Functional outcome was assessed at 3 months using the modified Rankin Scale. Logistic regression and Cox proportional hazards models were generated to assess predictors of UEAV and its relationship to delayed cerebral ischemia (DCI) and outcome. Multiple imputation methods were used to address data lost to follow-up. RESULTS The cohort incidence rate of UEAV was 4.6%. Multivariable logistic regression analysis revealed that younger age, sentinel bleed, and poor admission clinical grade were significantly associated with UEAV. Patients with UEAV had a 2-fold increased risk of DCI (odds ratio [OR] 2.3, 95% confidence interval [CI] 1.4-3.9, p = 0.002) and cerebral infarction (OR 2.0, 95% CI 1.0-3.9, p = 0.04), after adjusting for known predictors. Excluding patients who experienced sentinel bleeding did not change this effect. Patients with UEAV also had a significantly higher hazard for DCI in a multivariable model. UEAV was not found to be significantly associated with poor functional outcome (OR 0.8, 95% CI 0.4-1.6, p = 0.5). CONCLUSIONS UEAV may be less frequent than has been reported previously. Patients who exhibit UEAV are at higher risk for refractory DCI that results in cerebral infarction. These patients may benefit from earlier monitoring for signs of DCI and more aggressive treatment. Further study is needed to determine the long-term functional significance of UEAV.

Cerebral angiitis associated with subarachnoid hemorrhage in Castleman's disease: report of two cases

Background

Multicentric Castleman’s disease (MCD) is characterized by a systemic lymphoproliferative disorder affecting systemic lymph nodes. Cerebrovascular involvements have rarely been reported, and to our knowledge, cerebral angiitis causing subarachnoid hemorrhage (SAH) in patients with Multicentric Castleman’s disease (MCD) has not been previously described.

Case presentation

We identified two cases of MCD with SAH who were receiving immunosuppressive therapy with low dose prednisolone. Both patients presented with sudden-onset headache and were diagnosed with cortical SAH in the sulci by a computed tomography scan. Digital subtraction angiography showed segmental stenosis in the peripheral area of the middle cerebral artery. In both cases, cerebral angiitis causing SAH induced by a systemic inflammatory condition and elevated levels of interleukin (IL) -6 were suspected and resolved over a period of several months.

Conclusion

Our cases highlight the clinical diversity of the potential causes of cerebral angiitis and expand the association of MCD and cortical SAH; however, cortical SAH patients have a more favorable outcome than aneurysmal SAH patients.

Early Vasospasm after Aneurysmal Subarachnoid Hemorrhage Predicts the Occurrence and Severity of Symptomatic Vasospasm and Delayed Cerebral Ischemia

Background: Cerebral vasospasm usually develops several days after subarachnoid hemorrhage (SAH) and is generally acknowledged as a strong outcome predictor. In contrast, much less is known about the nature and eventual consequences of early angiographic vasospasm (EAVS) seen on admission digital subtraction angiography (DSA). Therefore, we aimed at identifying the risk factors and clinical impact of EAVS after SAH. Methods: Five hundred and thirty-one SAH patients with admission DSA performed within 72 h after the bleeding event were selected from a comprehensive database containing all consecutive SAH patients treated at our institution between January 2005 and December 2012. Predictors of EAVS, as well as associations between EAVS and delayed vasospasm-related complications, and unfavorable outcome (defined as modified Rankin scale >3) were evaluated in univariate and multivariate analyses. Results: EAVS was seen on 60 DSAs (11.3%) and was independently correlated with delayed symptomatic vasospasm requiring intra-arterial spasmolysis (OR 5.24, p < 0.0001), angioplasty (OR 2.56, p = 0.015) and repetitive endovascular treatment (OR 4.71, p < 0.0001). EAVS also increased the risk for multiple versus single territorial infarction on the follow-up CT scan(s) (OR 2.04, p = 0.047) and independently predicted unfavorable outcome (OR 2.93, p = 0.008). The presence of radiographic signs suspicious for fibromuscular dysplasia were independently associated with the occurrence of EAVS (OR 2.98, p = 0.026) and the need for repetitive endovascular vasospasm treatment (OR 3.95, p = 0.019). Conclusions: In view of the strong correlation with delayed symptomatic vasospasm and its ischemic complications, EAVS can be considered an alerting signal for severe symptomatic vasospasm. Therefore, more attention should be paid to the presence of EAVS on admission DSA.

Early identification of individuals at high risk for cerebral infarction after aneurysmal subarachnoid hemorrhage: the BEHAVIOR score

Cerebral infarction (CI) is a crucial complication of aneurysmal subarachnoid hemorrhage (SAH) associated with poor clinical outcome. We aimed at developing an early risk score for CI based on clinical characteristics available at the onset of SAH. Out of a database containing 632 consecutive patients with SAH admitted to our institution from January 2005 to December 2012, computed tomography (CT) scans up to day 42 after ictus were evaluated for CIs. Different parameters from admission up to aneurysm treatment were collected with subsequent construction of a risk score. Seven clinical characteristics were independently associated with CI and included in the Risk score (BEHAVIOR Score, 0 to 11 points): Blood on CT scan according to Fisher grade ⩾3 (1 point), Elderly patients (age ⩾55 years, 1 point), Hunt&Hess grade ⩾4 (1 point), Acute hydrocephalus requiring external liquor drainage (1 point), Vasospasm on initial angiogram (3 points), Intracranial pressure elevation >20 mm Hg (3 points), and treatment of multiple aneurysms ('Overtreatment', 1 point). The BEHAVIOR score showed high diagnostic accuracy with respect to the absolute risk for CI (area under curve=0.806, P<0.0001) and prediction of poor clinical outcome at discharge (P<0.0001) and after 6 months (P=0.0002). Further validation in other SAH cohorts is recommended.

Prognostic Value of the Amount of Bleeding After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND:

Quantitative estimation of the hemorrhage volume associated with aneurysm rupture is a new tool of assessing prognosis.

OBJECTIVE:

To determine the prognostic value of the quantitative estimation of the amount of bleeding after aneurysmal subarachnoid hemorrhage, as well the relative importance of this factor related to other prognostic indicators, and to establish a possible cut-off value of volume of bleeding related to poor outcome.

METHODS:

A prospective cohort of 206 patients consecutively admitted with the diagnosis of aneurysmal subarachnoid hemorrhage to Hospital 12 de Octubre were included in the study. Subarachnoid, intraventricular, intracerebral, and total bleeding volumes were calculated using analytic software. For assessing factors related to prognosis, univariate and multivariate analysis (logistic regression) were performed. The relative importance of factors in determining prognosis was established by calculating their proportion of explained variation. Maximum Youden index was calculated to determine the optimal cut point for subarachnoid and total bleeding volume.

RESULTS:

Variables independently related to prognosis were clinical grade at admission, age, and the different bleeding volumes. The proportion of variance explained is higher for subarachnoid bleeding. The optimal cut point related to poor prognosis is a volume of 20 mL both for subarachnoid and total bleeding.

CONCLUSION:

Volumetric measurement of subarachnoid or total bleeding volume are both independent prognostic factors in patients with aneurysmal subarachnoid hemorrhage. A volume of more than 20 mL of blood in the initial noncontrast computed tomography is related to a clear increase in poor outcome risk.

Redefining secondary injury after subarachnoid hemorrhage in light of multimodal advanced neuroimaging, intracranial and transcranial neuromonitoring: beyond vasospasm

The classic idea that arterial narrowing, called vasospasm (VSP), represents the hallmark of secondary injury after subarachnoid hemorrhage, has been challenged. The more complex and pleiotropic pathophysiological repercussions from the irruption of arterial blood into the subarachnoid layers go beyond the ascribed VSP. Putting adjectives in front of this term, such as "symptomatic," "microdialytic," or "angiographic" VSP, is misleading. Delayed cerebral ischemia (DCI) is a better term but remains restrictive to severe hypoperfusive injury and neglects oligemia, edema, and metabolic nonischemic injuries. In recognition of these issues, the international conference on VSP integrated "neurovascular events" into its name ( www.vasospasm2013.com ) and a multidisciplinary research group was formed in 2010 to study subgroups of DCI/VSP and their respective significance.In three parts, this tiered article provides a broader definitional envelope for DCI and secondary neurovascular insults after SAH, with a rubric for each subtype of delayed neuronal dysfunction. First, it pinpoints the need for nosologic precision and covers current terminological inconsistency. Then, it highlights the input of neuroimaging and neuromonitoring in defining secondary injurious processes. Finally, a new categorization of deteriorating patients is proposed, going beyond a hierarchical or dichotomized definition of VSP/DCI, and common data elements are suggested for future trials.

Acute angiographic vasospasm and the incidence of delayed cerebral vasospasm: preliminary results

BACKGROUND

More than half of subarachnoid hemorrhage (SAH) patients develop angiographically detectable delayed cerebral vasospasm (dCVS). It mostly occurs between days 4 and 15 after ictus and can be associated with neurological deficits that contribute to increased morbidity and mortality after SAH. Although dCVS is well studied, there are only a handful of reports on the acute phase of vasospasm (APV) occurring after treatment of intracranial aneurysms, whether ruptured or not. The aim of the current study is to elucidate the association of intraoperative cerebral vasospasm (iCVS) with the incidence of dCVS.

METHOD

We retrospectively reviewed consecutive patients who were treated for aneurysmal SAH or incidental aneurysms during the study period. Angiograms of patients undergoing aneurysm treatment were reviewed. Spasm severity was classified with respect to reduction in the transverse diameter. Mild vasospasm was defined as a reduction in vessel diameter of 10-30 %; moderate, 30-50 %; and severe vasospasm, >50 %. Statistical significance was tested using the Χ² test with p < 0.05. Correlations between iCVS and other factors were investigated.

RESULTS

Of 109 patients, 77 patients (33 men and 44 women) presented with acute SAH and 32 patients (9 men and 23 women) were treated for incidental aneurysms. Seventeen (22 %) of 77 patients presenting with acute SAH had evidence of acute (within 72 h after SAH ictus) CVS. In 16 of 17 (94.1 %) patients, this vasospasm was observed immediately after treatment and was therefore termed iCVS. Eleven (30 %) of 36 patients undergoing clipping and 5 (14 %) of 36 patients with endovascular aneurysm occlusion had iCVS (p = 0.07). Patients presenting with acute SAH had a higher incidence of iCVS than patients undergoing elective aneurysm treatment (p = 0.02). Only one patient (3 %) had iCVS in the elective treatment group whereas 16 (20 %) had iCVS after SAH. The incidence of dCVS, delayed ischemic neurological deficits (DNDs), and poor outcome in patients presenting with iCVS during surgical treatment of ruptured aneurysms was 56 % (p = 0.001), 63 % (p = 0.02), and 38 % (p = 0.14), respectively.

CONCLUSION

APV exists and is a common finding in patients with SAH. Further studies are warranted to correlate the presence of APV with postoperative ischemia, dCVS, and outcome.

Endovascular treatment of subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a common and devastating form of stroke. A large number of patients with aSAH develop angiographic or clinical vasospasm responsible for high morbidity and mortality. Rapid advances in the field of interventional neurology and the development of minimally invasive techniques have resulted in expansion of potential therapeutic applications. Treatment of aSAH has benefited from this rapid advance in the field of endovascular therapies. In the first section of the review, we discuss the therapeutic options and techniques for embolizations of intracranial aneurysms. In the second section, we discuss evolving endovascular treatment methods employed to intervene in delayed complications of cerebral vasospasm in patients with aSAH.

Innovative approach for prevention and treatment of post subarachnoid hemorrhage vasospasm: A preliminary report

More than one third of patients with subarachnoid hemorrhage (SAH) develop clinically significant vasospasm, as a leading morbidity and mortality factor for these patients. It is widely accepted that a) Degradation products of blood are the causative factors of vasospasm b) The amount of subarachnoid blood seen on admission CT is correlated to the risk of vasospasm c) Reducing the subarachnoid clot burden at the time of surgery reduces the risk of vasospasm. But there is no existing method to clear the blood from subarachnoid spaces satisfactorily. We have evaluated safety and feasibility of fluid exchange catheter system in SAH, to achieve this goal. We were successful in clearing cisternal blood in three patients with aneurysmal rupture with fluid exchange catheter system. Baseline CT scan of brain was performed immediately after the surgery and then at the end of irrigation. The amount of subarachnoid blood was evaluated. This innovative, fluid exchange catheter system infuses and aspirates micro volumes of drug solution in a cyclic mode, ensuring isobaric exchange of fluids. The result is good clearance of blood in subarachnoid spaces were seen in all the patients. Also, significant improvement in neurological deficits secondary to vasospasm was seen. We conclude that the fluid exchange catheter system is safe and adoptable in neurosurgical practice.

Risk profile of patients with poor-grade aneurysmal subarachnoid hemorrhage using early perfusion computed tomography

OBJECTIVE

To determine whether perfusion computed tomography (CT) is useful for identifying patients with poor-grade subarachnoid hemorrhage (SAH) with reversible etiologies and whether early obliteration in patients with poor-grade aneurysmal SAH leads to favorable outcomes.

METHODS

Patients with new-onset aneurysmal SAH in World Federation of Neurological Surgeons (WFNS) grade IV or V neurologic condition who had perfusion CT performed at admission were eligible for the study. The study retrospectively enrolled 38 patients seen between January 2007 and July 2009. The decision to perform an early obliteration was made by the family after a discussion with the neurosurgeons, neurointensivists, and interventional radiologists. The functional outcomes were correlated with the Glasgow Outcome Scale (GOS) at 6 months, and quantitative perfusion CT data were collected.

RESULTS

This study included 10 (26%) grade IV and 28 (74%) grade V patients. Favorable outcomes occurred in 19 (50%) patients, and 11 (29%) patients died. After a multivariate logistic regression analysis of the parameters, older age (odds ratio 1.104, P = 0.0317), bilateral prolonged mean transient time (MTT) at the thalami (odds ratio 4.155, P = 0.0362), and early obliteration (odds ratio 0.098, P = 0.003) were predictive of poor outcome.

CONCLUSIONS

Early bilateral prolonged MTT at the thalami and old age are associated with a poor outcome. Early obliteration benefits a significant portion of SAH patients.

Acute ischemic injury on diffusion-weighted magnetic resonance imaging after poor grade subarachnoid hemorrhage

BACKGROUND

Poor clinical condition is the most important predictor of neurological outcome and mortality after subarachnoid hemorrhage (SAH). Rupture of an intracranial aneurysm was shown to be associated with acute ischemic brain injury in poor grade patients in autopsy studies and small magnetic resonance imaging series.

METHODS

We performed diffusion-weighted magnetic resonance imaging (DWI) within 96 h of onset in 21 SAH patients with Hunt-Hess grade 4 or 5 enrolled in the Columbia University SAH Outcomes Project between July 2004 and February 2007. We analyzed demographic, radiological, clinical data, and 3 months outcome.

RESULTS

Of the 21 patients 13 were Hunt-Hess grade 5, and eight were grade 4. Eighteen patients (86%) displayed bilateral and symmetric abnormalities on DWI, but not on computed tomography (CT). Involved regions included both anterior cerebral artery territories (16 patients), and less often the thalamus and basal ganglia (4 patients), middle (6 patients) or posterior cerebral artery territories (2 patients), or cerebellum (2 patients). At 1-year, 15 patients were dead (life support had been withdrawn in 6), 2 were moderately to severely disabled (modified Rankin Scale [mRS] = 4-5), and 4 had moderate-to-no disability (mRS = 1-3).

CONCLUSIONS

Admission DWI demonstrates multifocal areas of acute ischemic injury in poor grade SAH patients. These ischemic lesions may be related to transient intracranial circulatory arrest, acute vasoconstriction, microcirculatory disturbances, or decreased cerebral perfusion from neurogenic cardiac dysfunction. Ischemic brain injury in poor grade SAH may be a feasible target for acute resuscitation strategies.

Global cerebral edema and brain metabolism after subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Global cerebral edema is common among patients with poor-grade subarachnoid hemorrhage and is associated with poor outcome. Currently no targeted therapy exists largely due to an incomplete understanding of the underlying mechanisms.

METHODS

This is a prospective observational study including 39 consecutive patients with poor-grade subarachnoid hemorrhage with multimodal neuromonitoring. Levels of microdialysate lactate-pyruvate ratio, episodes of cerebral metabolic crisis (lactate-pyruvate ratio >40 and brain glucose <0.7 mmol/L), brain tissue oxygen tension, cerebral perfusion pressure, and transcranial Doppler sonography flow velocities were analyzed.

RESULTS

Median age was 54 years (range, 45 to 61 years) and 62% were female. Patients with global cerebral edema on admission (n=24 [62%]) had a higher incidence of metabolic crisis in the first 12 hours of monitoring (n=15 [15% versus 2%], P<0.05) and during the total time of neuromonitoring (20% versus 3%, P<0.001) when compared to those without global cerebral edema. There was no difference in brain tissue oxygen tension or cerebral perfusion pressure between the groups; however, in patients with global cerebral edema, a higher cerebral perfusion pressure was associated with lower lactate-pyruvate ratio (P<0.05). Episodes of metabolic crisis were associated with poor outcome (modified Rankin Scale score 5 or 6, P<0.05).

CONCLUSIONS

In patients with poor-grade subarachnoid hemorrhage, global cerebral edema is associated with early brain metabolic distress.

The role of transcranial Doppler ultrasonography in the diagnosis and management of vasospasm after aneurysmal subarachnoid hemorrhage

Transcranial Doppler ultrasonography (TCD) is a tool employed by the neurosurgeon and neurointensivist in the management of vasospasm in the intensive care unit after aneurysmal subarachnoid hemorrhage. A review of the current indications, monitoring parameters, indices, and relevance of modern TCD technology is provided, as well as algorithms for the use of TCD ultrasonography in the management of patients with subarachnoid hemorrhage. Other current uses of TCD ultrasonography are also discussed in the setting of neurocritical care.

Elucidating novel mechanisms of brain injury following subarachnoid hemorrhage: an emerging role for neuroproteomics

Subarachnoid hemorrhage (SAH) is a devastating neurological injury associated with significant patient morbidity and death. Since the first demonstration of cerebral vasospasm nearly 60 years ago, the preponderance of research has focused on strategies to limit arterial narrowing and delayed cerebral ischemia following SAH. However, recent clinical and preclinical data indicate a functional dissociation between cerebral vasospasm and neurological outcome, signaling the need for a paradigm shift in the study of brain injury following SAH. Early brain injury may contribute to poor outcome and early death following SAH. However, elucidation of the complex cellular mechanisms underlying early brain injury remains a major challenge. The advent of modern neuroproteomics has rapidly advanced scientific discovery by allowing proteome-wide screening in an objective, nonbiased manner, providing novel mechanisms of brain physiology and injury. In the context of neurosurgery, proteomic analysis of patient-derived CSF will permit the identification of biomarkers and/or novel drug targets that may not be intuitively linked with any particular disease. In the present report, the authors discuss the utility of neuroproteomics with a focus on the roles for this technology in understanding SAH. The authors also provide data from our laboratory that identifies high-mobility group box protein-1 as a potential biomarker of neurological outcome following SAH in humans.

Brain edema formation and neurological impairment after subarachnoid hemorrhage in rats

Object

Global cerebral edema is an independent risk factor for early death and poor outcome after subarachnoid hemorrhage (SAH). In the present study, the time course of brain edema formation, neurological deficits, and neuronal cell loss were investigated in the rat filament SAH model.

Methods

Brain water content and neurological deficits were determined in rats randomized to sham (1-, 24-, or 48-hour survival), SAH by endovascular perforation (1-, 24-, or 48-hour survival), or no surgery (control). The neuronal cell count (CA1–3) was quantified in a separate set of SAH (6-, 24-, 48-, or 72-hour survival) and shamoperated animals.

Results

Brain water content increased significantly 24 (80.2 ± 0.4% [SAH] vs 79.2 ± 0.1% [sham]) and 48 hours (79.8 ± 0.2% [SAH] vs 79.3 ± 0.1% [sham]) after SAH. The neuroscore was significantly worse after SAH (33 ± 15 [24 hours after SAH] vs 0 ± 0 points [sham]) and correlated with the extent of brain edema formation (r = 0.96, p < 0.001). No hippocampal damage was present up to 72 hours after SAH.

Conclusions

Brain water content and neurological dysfunction reached a maximum at 24 hours after SAH. This time point, therefore, seems to be optimal to test the effects of therapeutic interventions on brain edema formation. Neuronal cell loss was not present in CA1–3 up to 72 hours of SAH. Therefore, morphological damage needs to be evaluated at later time points.

Transcranial Doppler for predicting delayed cerebral ischemia after subarachnoid hemorrhage

OBJECTIVE

Transcranial Doppler (TCD) is widely used to monitor the temporal course of vasospasm after subarachnoid hemorrhage (SAH), but its ability to predict clinical deterioration or infarction from delayed cerebral ischemia (DCI) remains controversial. We sought to determine the prognostic utility of serial TCD examination after SAH.

METHODS

We analyzed 1877 TCD examinations in 441 aneurysmal SAH patients within 14 days of onset. The highest mean blood flow velocity (mBFV) value in any vessel before DCI onset was recorded. DCI was defined as clinical deterioration or computed tomographic evidence of infarction caused by vasospasm, with adjudication by consensus of the study team. Logistic regression was used to calculate adjusted odds ratios for DCI risk after controlling for other risk factors.

RESULTS

DCI occurred in 21% of patients (n = 92). Multivariate predictors of DCI included modified Fisher computed tomographic score (P = 0.001), poor clinical grade (P = 0.04), and female sex (P = 0.008). After controlling for these variables, all TCD mBFV thresholds between 120 and 180 cm/s added a modest degree of incremental predictive value for DCI at nearly all time points, with maximal sensitivity by SAH day 8. However, the sensitivity of any mBFV more than 120 cm/s for subsequent DCI was only 63%, with a positive predictive value of 22% among patients with Hunt and Hess grades I to III and 36% in patients with Hunt and Hess grades IV and V. Positive predictive value was only slightly higher if mBFV exceeded 180 cm/s.

CONCLUSION

Increased TCD flow velocities imply only a mild incremental risk of DCI after SAH, with maximal sensitivity by day 8. Nearly 40% of patients with DCI never attained an mBFV more than 120 cm/s during the course of monitoring. Given the poor overall sensitivity of TCD, improved methods for identifying patients at high risk for DCI after SAH are needed.

RESUSCITATION AND CRITICAL CARE OF POOR-GRADE SUBARACHNOID HEMORRHAGE

AS OUTCOMES HAVE improved for patients with aneurysmal subarachnoid hemorrhage, most mortality and morbidity that occur today are the result of severe diffuse brain injury in poor-grade patients. The premise of this review is that aggressive emergency cardiopulmonary and neurological resuscitation, coupled with early aneurysm repair and advanced multimodality monitoring in a specialized neurocritical care unit, offers the best approach for achieving further improvements in subarachnoid hemorrhage outcomes. Emergency care should focus on control of elevated intracranial pressure, optimization of cerebral perfusion and oxygenation, and medical and surgical therapy to prevent rebleeding. In the postoperative period, advanced monitoring techniques such as continuous electroencephalography, brain tissue oxygen monitoring, and microdialysis can detect harmful secondary insults, and may eventually be used as end points for goal-directed therapy, with the aim of creating an optimal physiological environment for the comatose injured brain. As part of this paradigm shift, it is essential that aggressive surgical and medical support be linked to compassionate end-of-life care. As neurosurgeons become confident that comfort care can be implemented in a straightforward fashion after a failed trial of early maximal intervention, the usual justification for withholding treatment (survival with neurological devastation) becomes less relevant, and lives may be saved as more patients recover beyond expectations.

Effect of electrical stimulation of the cervical spinal cord on blood flow following subarachnoid hemorrhage

Object

Cervical spinal cord stimulation (SCS) increases global cerebral blood flow (CBF) and ameliorates cerebral ischemia according to a number of experimental models as well as some anecdotal reports in humans. Nonetheless, such stimulation has not been systematically applied for use in cerebral vasospasm. In the present study the authors examined the effect of cervical SCS on cerebral vasoconstriction in a double-hemorrhage model in rats.

Methods

Subarachnoid hemorrhage (SAH) was induced with 2 blood injections through an indwelling catheter in the cisterna magna. Spinal cord stimulation was applied 90 minutes after induction of the second SAH (Day 0) or on Day 5 post-SAH. Measurements of the basilar artery (BA) diameter and cross-sectional area and regional CBF (using laser Doppler flowmetry and 14C-radiolabeled N-isopropyl-p-iodoamphetamine hydrochloride) were obtained and compared between SAH and sham-operated control rats that did not receive SCS.

Results

At Day 0 after SAH, there were slight nonsignificant decreases in BA diameter and cross-sectional area (89 ± 3% and 81 ± 4%, respectively, of that in controls) in no-SCS rats. At this time point, BA diameter and crosssectional area were slightly increased (116 ± 6% and 132 ± 9%, respectively, compared with controls, p < 0.001) in SCS-treated rats. On Day 5 after SAH, no-SCS rats had marked decreases in BA diameter and cross-sectional area (64 ± 3% and 39 ± 4%, respectively, compared with controls, p < 0.001) and corrugation of the vessel wall. These changes were reversed in rats that had received SCS (diameter, 110 ± 9% of controls; area, 106 ± 4% of controls; p < 0.001). Subarachnoid hemorrhage reduced CBF at Days 0 and 5 post-SAH, and SCS increased flows at both time points, particularly in regions supplied by the middle cerebral artery.

Conclusions

Data in this study showed that SCS can reverse BA constriction and improve global CBF in this SAH model. Spinal cord stimulation may represent a useful adjunct in the treatment of vasospasm.

Clazosentan, an endothelin receptor antagonist, prevents early hypoperfusion during the acute phase of massive experimental subarachnoid hemorrhage: a laser Doppler flowmetry study in rats

Object

Acute cerebral hypoperfusion and early disturbances in cerebral autoregulation after subarachnoid hemorrhage (SAH) have been demonstrated repeatedly and have been shown to contribute significantly to acute and secondary brain injury. Acute vasoconstriction has been identified as a major contributing factor. Although increasing evidence implicates endothelin (ET)–1 in the development of cerebral vasospasm, its role in the acute phase after SAH has not yet been investigated. The purpose of this study was to further determine the role of ET in the first minutes to hours after massive experimental SAH induced by prophylactic treatment with the ET receptor antagonist clazosentan.

Methods

Subarachnoid hemorrhage was induced in 22 anesthetized rats by injection of 0.5-ml arterial, nonheparinized blood into the cisterna magna over the course of 60 seconds. In addition to monitoring intracranial pressure (ICP) and mean arterial blood pressure, laser Doppler flowmetry (LDF) probes were placed stereotactically over the cranial windows to allow online recording of cerebral blood flow (CBF) starting 30 minutes prior to SAH and continuing for 3 hours after SAH. The control group (Group A, 11 rats) received vehicle saline solution via a femoral catheter before SAH, and a second group (Group B, 11 rats) was treated prophylactically with clazosentan, an ETA receptor antagonist. Treatment was started 30 minutes prior to bolus injection (1 mg/kg body weight), immediately followed by a continuous infusion of 1 mg/kg body weight/hr until the end of the experiment.

Results

Induction of SAH in the rats caused an immediate increase in ICP, which led to an acute decrease in cerebral perfusion pressure (CPP). Perfusion, as measured with LDF, was found to have decreased relative to baseline by 30 ±20% in the control group and 20 ±9% in the clazosentan-treated group. Intracranial pressure and CPP recovered comparably in both groups thereafter within minutes. Control animals demonstrated prolonged hypoperfusion with a loss of autoregulation independent of CPP changes, finally approaching 80% of baseline values toward the end of the experiment. The authors observed that clazosentan did not influence peracute CPP-dependent hypoperfusion, but prevented continuous CBF reduction. Laser Doppler flowmetry perfusion readings remained depressed in control animals at 73 ±19% of baseline in comparison with 106 ±25% of baseline in clazosentan-treated animals (p = 0.001).

Conclusions

The first hours after a massive experimental SAH can be characterized by a CPP-independent compromise in cerebral perfusion. Prophylactic treatment with the ET receptor antagonist clazosentan prevented hypoperfusion. It is known that in the first days after SAH, a reduction in CBF correlates clinically to high-grade SAH. Although research currently focuses on delayed vasospasm, administration of vasoactive drugs in the acute phase of SAH may reverse perfusion deficits and improve patient recovery.

Reversible cerebral vasoconstriction syndrome associated with subarachnoid hemorrhage

INTRODUCTION

Reversible cerebral vasoconstriction syndrome (RCVS) is a rare vasculopathy of unknown etiology. Ischemic stroke and intracerebral hemorrhage are well-documented sequelae, but subarachnoid hemorrhage is an uncommon complication of RCVS.

METHODS AND RESULTS

We report six cases of RCVS associated with subarachnoid hemorrhage. Two cases occurred in postpartum women, two in women with a history of migraines, one in a woman who recently stopped taking her anti-hypertensive medications, and one in a man after sexual intercourse. All six patients presented with the classic thunderclap headache. Two patients experienced generalized tonic-clonic seizures, and two patients had small ischemic infarcts. Segmental vasoconstriction was demonstrated on cerebral angiography in all six cases. Aneurysmal subarachnoid hemorrhage and other etiologies were excluded. Reversibility of the segmental vasoconstriction was confirmed by follow-up angiography in four patients and by transcranial Doppler sonography in two patients. All six patients had an excellent neurological outcome.

CONCLUSIONS

Reversible cerebral vasoconstriction syndrome may be associated with subarachnoid hemorrhage. RCVS should be included in the differential diagnosis of non-aneurysmal subarachnoid hemorrhage.

Cerebral infarction associated with acute subarachnoid hemorrhage

BACKGROUND

Cerebral infarction is a common complication of aneurysmal subarachnoid hemorrhage (SAH), but usually occurs several days after onset as a complication of vasospasm or aneurysm repair. The frequency, causes, and clinical impact of acute infarction associated with the primary hemorrhage are poorly understood.

METHODS

We evaluated the presence of cerebral infarction on admission CT in 487 patients admitted within 3 days of SAH onset to our center between July 1996 and September 2002. Infarctions due to angiography or treatment complications were rigorously excluded. Outcome at 3 months was assessed with the modified Rankin Scale.

RESULTS

A total of 17 patients (3%) had acute infarction on admission CT; eight had solitary and nine had multiple infarcts. Solitary infarcts usually appeared in the vascular territory distal to the ruptured aneurysm, whereas multiple infarcts tended to be territorial and symmetric. Global cerebral edema (P < 0.001), coma on presentation (P = 0.001), intraventricular hemorrhage (P = 0.002), elevated APACHE-II physiological subscores (P = 0.026) and loss of consciousness at onset (P = 0.029) were associated with early cerebral infarction. Mortality (P = 0.003) and death or moderate-to-severe disability (mRS 4-6, P = 0.01) occurred more frequently in the early cerebral infarction group.

CONCLUSIONS

Early cerebral infarction on CT is a rare but devastating complication of acute SAH. The observed associations with coma, global cerebral edema, intraventricular hemorrhage, and loss of consciousness at onset suggest that intracranial circulatory arrest may play a role in the pathogenesis of this disorder.

Clinical review: Prevention and therapy of vasospasm in subarachnoid hemorrhage

Vasospasm is one of the leading causes of morbidity and mortality following aneurysmal subarachnoid hemorrhage (SAH). Radiographic vasospasm usually develops between 5 and 15 days after the initial hemorrhage, and is associated with clinically apparent delayed ischemic neurological deficits (DID) in one-third of patients. The pathophysiology of this reversible vasculopathy is not fully understood but appears to involve structural changes and biochemical alterations at the levels of the vascular endothelium and smooth muscle cells. Blood in the subarachnoid space is believed to trigger these changes. In addition, cerebral perfusion may be concurrently impaired by hypovolemia and impaired cerebral autoregulatory function. The combined effects of these processes can lead to reduction in cerebral blood flow so severe as to cause ischemia leading to infarction. Diagnosis is made by some combination of clinical, cerebral angiographic, and transcranial doppler ultrasonographic factors. Nimodipine, a calcium channel antagonist, is so far the only available therapy with proven benefit for reducing the impact of DID. Aggressive therapy combining hemodynamic augmentation, transluminal balloon angioplasty, and intra-arterial infusion of vasodilator drugs is, to varying degrees, usually implemented. A panoply of drugs, with different mechanisms of action, has been studied in SAH related vasospasm. Currently, the most promising are magnesium sulfate, 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors, nitric oxide donors and endothelin-1 antagonists. This paper reviews established and emerging therapies for vasospasm.

Early vasospasm on admission angiography in patients with aneurysmal subarachnoid hemorrhage is a predictor for in-hospital complications and poor outcome

BACKGROUND AND PURPOSE

Early vasospasm (EVSP), defined here as arterial narrowing seen on diagnostic angiography within the first 48 hours of aneurysmal rupture, is a rarely reported and poorly defined phenomenon in patients with subarachnoid hemorrhage (SAH). The purpose of this study was to characterize EVSP in a large database of such patients.

METHODS

We analyzed the relationship of EVSP to clinical characteristics, in-hospital complications, and outcome at 3 months among 3478 patients entered into 4 prospective, randomized, double-blind, placebo-controlled trials of tirilazad conducted in neurosurgical centers around the world between 1991 and 1997.

RESULTS

Three hundred thirty-nine (10%) of 3478 patients had EVSP. EVSP was significantly more likely in patients with poor neurological grade on admission, history of SAH, intracerebral hematoma, larger aneurysm, thick SAH on cranial computed tomography, and intraventricular hemorrhage. EVSP was not associated with delayed cerebral vasospasm. After adjustment for differences in admission characteristics, EVSP was associated with cerebral infarction (adjusted odds ratios [OR]=1.51; 95% CI, 1.18 to 1.94; P=0.001), neurological worsening (OR=1.41; 95% CI, 1.10 to 1.81; P=0.007), and unfavorable outcome (OR=1.51; 95% CI, 1.15 to 2.00; P=0.003). In addition, there was a trend for patients with increasingly severe EVSP to have unfavorable outcome (OR=1.84 for mild and OR=2.66 for moderate/severe EVSP).

CONCLUSIONS

EVSP was seen in 10% of SAH patients and was predictive of cerebral infarction and neurological worsening as well as unfavorable outcome at 3 months. EVSP was not associated with late vasospasm. EVSP may be as important as delayed vasospasm in predicting complications and long-term morbidity in SAH patients.

Characterization of perioperative seizures and epilepsy following aneurysmal subarachnoid hemorrhage

Object. The reported incidence, timing, and predictive factors of perioperative seizures and epilepsy after subarachnoid hemorrhage (SAH) have differed considerably because of a lack of uniform definitions and variable follow-up periods. In this study the authors evaluate the incidence, temporal course, and predictive factors of perioperative seizures and epilepsy during long-term follow up of patients with SAH who underwent surgical treatment.

Methods. Two hundred seventeen patients who survived more than 2 years after surgery for ruptured intracranial aneurysms were enrolled and retrospectively studied. Episodes were categorized into onset seizures (≤ 12 hours of initial hemorrhage), preoperative seizures, postoperative seizures, and late epilepsy, according to their timing.

The mean follow-up time was 78.7 months (range 24–157 months). Forty-six patients (21.2%) had at least one seizure post-SAH. Seventeen patients (7.8%) had onset seizures, five (2.3%) had preoperative seizures, four (1.8%) had postoperative seizures, 21 (9.7%) had at least one seizure episode after the 1st week postoperatively, and late epilepsy developed in 15 (6.9%). One (3.8%) of 26 patients with perioperative seizures (onset, preoperative, or postoperative seizure) had late epilepsy at follow up. The mean latency between the operation and the onset of late epilepsy was 8.3 months (range 0.3–19 months). Younger age (< 40 years old), loss of consciousness of more than 1 hour at ictus, and Fisher Grade 3 or greater on computerized tomography scans proved to be significantly related to onset seizures. Onset seizure was also a significant predictor of persistent neurological deficits (Glasgow Outcome Scale Scores 2–4) at follow up. Factors associated with the development of late epilepsy were loss of consciousness of more than 1 hour at ictus and persistent postoperative neurological deficit.

Conclusions. Although up to one fifth of patients experienced seizure(s) after SAH, more than half had seizure(s) during the perioperative period. The frequency of late epilepsy in patients with perioperative seizures (7.8%) was not significantly higher than those without such seizures (6.8%). Perioperative seizures did not recur frequently and were not a significant predictor for late epilepsy.

Ischemia triggered by spreading neuronal activation is induced by endothelin-1 and hemoglobin in the subarachnoid space

Delayed cerebral vasospasm has a major impact on the outcome of subarachnoid hemorrhage. Two important candidates to cause the arterial spasm are the red blood cell product oxyhemoglobin and the vasoconstrictor endothelin-1, although oxyhemoglobin alone is not sufficient to induce cerebral ischemia and endothelin-1 leads to ischemia only at relatively high concentrations. In this study, we demonstrated that the combination of oxyhemoglobin and endothelin-1 triggered spreading neuronal activation in rat cortex in vivo. In contrast with the expected transient increase of regional cerebral blood flow during spreading depression, however, cerebral blood flow decreased profoundly and was long-lasting, paralleled by delayed repolarization of the steady (direct current) potential. These changes are characteristic of cortical spreading ischemia. Replacing oxyhemoglobin for the nitric oxide synthase inhibitor Nomega-nitro-L-arginine mimicked these effects, implicating nitric oxide scavenging functions of oxyhemoglobin. Furthermore, the effect of endothelin-1 was related to a reduction of Na(+)-/K(+)-ATPase activity rather than solely to its vasoconstrictive properties. In conclusion, the threshold concentration of endothelin-1 that induces cerebral ischemia is profoundly reduced via a complex interaction between the neuronal/astroglial network and the cortical microcirculation if nitric oxide availability declines. The results may have implications for the understanding of subarachnoid hemorrhage-related cortical lesions.

Outcome following intracerebral hemorrhage and subarachnoid hemorrhage

Intracerebral hemorrhage and subarachnoid hemorrhage account for almost 20% of all stroke cases. Both forms of stroke are associated with a high morbidity and mortality rate. The incidence of intracerebral hemorrhage increases with the age and certain ethnical groups are more affected. Subarachnoid hemorrhage tends to occur in a much younger population than other types of strokes. Outcome predictors for intracerebral and subarachnoid hemorrhage have been extensively discussed in the literature. Based on the current literature, we review the morbidity and mortality rates and predictors of outcome for these two life-threatening diseases. Initial Glasgow Coma Scale (GCS) score, hematoma volume, and presence of ventricular blood are the most prominent predictors of outcome following intracerebral hemorrhage. Age and initial severity of neurologic deficits on presentation, measured by GCS, Hunt and Hess Scale or the World Federation of Neurological Surgeons Scale, are the most important predictors of outcome following subarachnoid hemorrhage.

Prognostic significance of hypernatremia and hyponatremia among patients with aneurysmal subarachnoid hemorrhage

OBJECTIVE

Abnormal serum sodium levels (hyponatremia and hypernatremia) are frequently observed during the acute period after aneurysmal subarachnoid hemorrhage (SAH) and may worsen cerebral edema and mass effect. We performed this study to determine the prognostic significance of serum sodium concentration abnormalities.

METHODS

We analyzed prospectively collected data for the placebo treatment group in a clinical trial conducted at 54 neurosurgical centers in North America. The presence of hypernatremia (serum sodium concentration of >145 mmol/L) and hyponatremia (serum sodium concentration of <135 mmol/L) was determined with serum sodium measurements obtained at admission and 3, 6, and 9 days after SAH. The effects of hypernatremia and hyponatremia on the risk of symptomatic vasospasm and on 3-month outcomes were analyzed after adjustment for the following potential confounding factors: age, sex, preexisting hypertension, admission Glasgow Coma Scale score, initial mean arterial pressure, subarachnoid clot thickness, intraventricular blood or intraparenchymal hematoma, ventricular dilation, and aneurysm size and location.

RESULTS

Of 298 patients in the analysis, 58 (19%) developed hypernatremia and 88 (30%) developed hyponatremia. Hypernatremia was significantly associated with poor outcomes (odds ratio, 2.7; 95% confidence interval, 1.2-6.1). A positive correlation was observed between the highest sodium values recorded and Glasgow Outcome Scale scores at 3 months (P < 0.0001 by analysis of variance). Hyponatremia was not associated with 3-month outcomes (odds ratio, 1.9; 95% confidence interval, 0.9-4.3). Neither hypernatremia nor hyponatremia was associated with the risk of symptomatic vasospasm.

CONCLUSION

Hyponatremia seems to be more common than hypernatremia after SAH. However, hypernatremia after SAH is independently associated with poor outcomes, and this association is independent of previously identified outcome predictors, including age and admission Glasgow Coma Scale scores. Further studies are needed to define the underlying mechanism of this association.

Asymptomatic versus symptomatic infarcts from vasospasm in patients with subarachnoid hemorrhage: serial magnetic resonance imaging

OBJECTIVE

By use of serial magnetic resonance imaging (MRI), we prospectively investigated the incidence of and the risk factors associated with infarction caused by vasospasm with or without a delayed ischemic neurological deficit (DIND) in patients with subarachnoid hemorrhage (SAH).

METHODS

In 125 patients who underwent surgery for early aneurysms, postoperative MRI scans were obtained at four time points. We defined an infarct from vasospasm as a new lesion not present on the initial MRI within 3 days after SAH and therefore not attributable to primary brain damage or surgical complications.

RESULTS

Overall, symptoms of infarction (i.e., DIND) occurred in 38% of patients (48 of 125); DIND with a new infarct on MRI was evident in 34% (43 patients), whereas 4% (5 patients) showed no new lesion but had a DIND. However, 29 patients (23%) showed a new infarct but no DIND on MRI studies (asymptomatic infarction). Asymptomatic ischemic lesions due to vasospasm tended to involve noneloquent brain areas in the territory of intraparenchymal perforators. Multivariate analysis identified variables associated with symptomatic infarction to be of poor SAH grade, advanced age of the patient, angiographic findings of vasospasm, multiple cortical infarcts on MRI studies consistent with vasospasm, and chronic hydrocephalus.

CONCLUSION

Analysis of the data confirmed the occurrence of asymptomatic infarcts due to vasospasm. These infarcts often developed in noneloquent areas representing perforator territory. MRI investigation of vasospastic lesions referable to intraparenchymal vessels such as perforators complements the study of extraparenchymal major vessel vasospasm in patients with SAH by computed tomographic angiography.

Effect of cisternal and ventricular blood on risk of delayed cerebral ischemia after subarachnoid hemorrhage: the Fisher scale revisited

BACKGROUND AND PURPOSE

Thick cisternal clot on CT is a well-recognized risk factor for delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH). Whether intraventricular hemorrhage (IVH) or intracerebral hemorrhage (ICH) predisposes to DCI is unclear. The Fisher CT grading scale identifies thick SAH but does not separately account for IVH or ICH.

METHODS

We studied 276 consecutively admitted patients with an available admission CT scan performed within 72 hours of onset. Demographic, clinical, laboratory, and neuroimaging data were recorded, and the amount and location of SAH, IVH, and ICH on admission CT scans were quantified. The relationship between these variables and DCI was analyzed separately and in combination with multiple logistic regression.

RESULTS

DCI developed in 20% of patients (54 of 276). Among SAH variables, thick clot completely filling any cistern or fissure was the best predictor of DCI (P=0.008), and among IVH variables, blood in both lateral ventricles was most predictive (P=0.001). These variables had independent predictive value for DCI in a multivariate analysis of CT findings, and both were included in a final multivariate model when evaluated in conjunction with other clinical risk factors: IVH (OR 4.1, 95% CI 1.7 to 9.8), SAH (OR 2.3, 95% CI 1.5 to 9.5), mean arterial pressure >112 mm Hg (OR 4.9, 95% CI 2.1 to 11.4), and transcranial Doppler mean velocity >140 cm/s within 5 days of hemorrhage (OR 3.8, 95% CI 1.5 to 9.5). Similar results were obtained in a repeat analysis with infarction due to vasospasm as the dependent variable.

CONCLUSIONS

SAH completely filling any cistern or fissure and IVH in the lateral ventricles are both risk factors for DCI, and their risk is additive. We propose a new SAH rating scale that accounts for the independent predictive value of subarachnoid and ventricular blood for DCI.