Volumetric analysis of subarachnoid hemorrhage: assessment of the reliability of two computerized methods and their comparison with other radiographic scales

Comparison of scales for the evaluation of aneurysmal subarachnoid haemorrhage: a retrospective cohort study

BACKGROUND/OBJECTIVES

Aneurysmal subarachnoid haemorrhage (aSAH) is a life-threatening event with major complications. Delayed cerebral infarct (DCI) occurs most frequently 7 days after aSAH and can last for a prolonged period. To determine the most predictive radiological scales in grading subarachnoid or ventricular haemorrhage or both for functional outcome at 3 months in a large aSAH population, we conducted a single-centre retrospective study.

METHODS

A 3-year single-centre retrospective cohort study of 230 patients hospitalised for aSAH was analysed. Initial computed tomography (CT) scans in patients hospitalised for aSAH were blindly assessed using eight grading systems: the Fisher grade, modified Fisher grade, Barrow Neurological Institute scale, Hijdra scale, Intraventricular Haemorrhage (IVH) score, Graeb score and LeRoux score.

RESULTS

Of 200 patients with aSAH who survived to day 7 and were included for DCI analysis, 39% of cases were complicated with DCI. The Hijdra scale was the best predictor for DCI, with a receiver operating characteristic area under the curve (ROCAUC) of 0.80 (95% confidence interval (CI), 0.74-0.85). The IVH score was the most effective grading system for predicting acute hydrocephalus, with a ROCAUC of 0.85 (95% CI, 0.79-0.89). In multivariate analysis, the Hijdra scale was the best predictor of the occurrence of DCI (hazard ratio, 1.18; 95% CI, 1.10-1.25).

CONCLUSIONS

Although these results have yet to be prospectively confirmed, our findings suggest that the Hijdra scale may be a good predictor of DCI and could be useful in daily clinical practice.

CLINICAL RELEVANCE STATEMENT

Better assessment of subarachnoid haemorrhage patients would allow for better prognostication and management of expectations, as well as referral for appropriate services and helping to appropriate use limited critical care resources.

KEY POINTS

Aneurysmal subarachnoid haemorrhage is a life-threatening event that causes severe disability and leads to major complications such as delayed cerebral infarction. Accurate assessment of the amount of blood in the subarachnoid spaces on computed tomography with the Hijdra scale can better predict the risk of delayed cerebral infarct. The Hijdra scale could be a good triage tool for subarachnoid haemorrhage patients.

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.

An update of predictors of cerebral infarction after aneurysmal subarachnoid hemorrhage: systematic review and meta-analysis

INTRODUCTION

Evidence about predictors of poor outcomes such as cerebral infarction (CI) after aneurysmal subarachnoid hemorrhage (aSAH) has not been fully elucidated.

EVIDENCE ACQUISITION

We performed a systematic review and meta-analysis on studies with adults with aSAH considering RCT and non-RCT, prospective, and retrospective cohort studies describing clinical, imaging as well as angiographic studies in patients with aSAH.

EVIDENCE SYNTHESIS

After reviewing the complete text, 11 studies were considered eligible, out of which four were ruled out. Degree of clinical severity was the most predictive factor with a higher degree at the presentation on different severity scales being associated with a statistically significant increasing the risk of suffering a CI following aSAH (OR 2.49 [95% CI 1.38-4.49] P=0.0003). Aneurysm size increased the risk of CI (OR 1.49 [95% CI 1.20-1.85] P=0.0003; I²=4%). In six studies analyzed, it was found that an important factor for the subsequent development of CI is vasospasm (OR 7.62 [2.19, 26.54], P=0.0001).

CONCLUSIONS

The development of vasospasm is a risk factor for CI development after aSAH. In our review, three factors were associated with an increased risk of CI: clinical severity at presentation, vasospasm, and aneurysm size. The major limitation of this meta-analysis is that included studies were conducted retrospectively or were post hoc analyses of a prospective trial.

Basic Surveillance Parameters Improve the Prediction of Delayed Cerebral Infarction After Aneurysmal Subarachnoid Hemorrhage

Background

To establish a practical risk chart for prediction of delayed cerebral infarction (DCI) after aneurysmal subarachnoid hemorrhage (aSAH) by using information that is available until day 5 after ictus.

Methods

We assessed all consecutive patients with aSAH admitted to our service between September 2008 and September 2015 (n = 417). The data set was randomly split into thirds. Two-thirds were used for model development and one-third was used for validation. Characteristics that were present between the bleeding event and day 5 (i.e., prior to >95% of DCI diagnoses) were assessed to predict DCI by using logistic regression models. A simple risk chart was established and validated.

Results

The amount of cisternal and ventricular blood on admission CT (Hijdra sum score), early sonographic vasospasm (i.e., mean flow velocity of either intracranial artery >160 cm/s until day 5), and a simplified binary level of consciousness score until day 5 were the strongest predictors of DCI. A model combining these predictors delivered a high predictive accuracy [the area under the receiver operating characteristic (AUC) curve of 0.82, Nagelkerke's R² 0.34 in the development cohort]. Validation of the model demonstrated a high discriminative capacity with the AUC of 0.82, Nagelkerke's R² 0.30 in the validation cohort.

Conclusion

Adding level of consciousness and sonographic vasospasm between admission and postbleed day 5 to the initial blood amount allows for simple and precise prediction of DCI. The suggested risk chart may prove useful for selection of appropriate candidates for interventions to prevent DCI.

Third Ventricle Volume Predicts Functional Outcome in Chronic Subdural Hematoma

OBJECTIVES

There is a lack of evidence demonstrating the utility of computed tomography (CT) to predict chronic subdural hematoma (CSDH) clinical outcomes. We aim to analyze the role of tomographic volumetric analysis in patients with CSDH.

METHODS

We performed a retrospective study of patients undergoing burr-hole craniostomy (BHC) for CSDH over five years at a tertiary care center. Degree of midline shift, radiographic density, subdural hematoma volume, acute blood volume, and third ventricle (3VV) and fourth ventricle (4VV) volume were estimated using semiautomatic segmentation of preoperative CT. Postoperative functional outcome was measured by two endpoints: National Institute of Health Stroke Scale (NIHSS) at discharge and short-term modified Rankin Scale (mRS) at 6-week follow-up. Univariate and multivariate analyses were performed using nonparametric tests. Discriminative capacity and optimal thresholds of independent variables were calculated by means of receiving-operative curves (ROC).

RESULTS

A total of 79 patients were included for analysis with a median age of 78.5 years. Greater preoperative 3VV independently correlated with poor discharge NIHSS (p = .01) and short-term mRS (p = .03). A cutoff value of 0.545 mL demonstrated the highest sensitivity (77.1%) and specificity (88.8%) with an odds ratio for an mRS functional dependence of 9.29 (p = .001).

CONCLUSIONS

Greater preoperative tomographic 3VV independently prognosticates poor discharge NIHSS and 6-week mRS. A threshold 3VV of 0.545 mL can be used to identify patients at higher risk of being dependent at first protocolized follow-up.

Predictive effects of admission white blood cell counts and hounsfield unit values on delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

OBJECTIVE

Neuroinflammatory response is deemed the primary pathogenesis of delayed cerebral ischemia (DCI) caused by aneurysmal subarachnoid hemorrhage (aSAH). Both white blood cell (WBC) count and Hounsfield Unit (HU) are gradually considered can reflect inflammation in DCI. This study aims to identify the relationship between WBC count and HU value and investigate the effects of both indicators in predicting DCI after aSAH.

METHODS

We enrolled 109 patients with aSAH admitted within 24 h of onset in our study. A multivariate logistic regression analysis was used to evaluate the admission WBC count, HU value, and combined WBC-HU associated with DCI. The receiver operating characteristic curve and area under the curve (AUC) were used to determine thresholds and detect the predictive ability of these predictors. These indicators were also compared with the established inflammation markers.

RESULTS

Thirty-six (33%) patients developed DCI. Both WBC count and HU value were strongly associated with the admission glucose level (ρ = .303, p = .001; ρ = .273, p = .004), World Federation of Neurosurgical Societies grade (ρ = .452, p < .001; ρ = .578; p < .001), Hunt-Hess grade (ρ = .450, p < .001; ρ = .510, p < .001), and modified Fisher scale score (ρ = .357, p < .001; ρ = .330, p < .001). After controlling these public variables, WBC count (ρ = .300, p = .002) positively correlated with HU value. An early elevated WBC (odds ratio [OR] 1.449, 95% confidence interval [CI]: 1.183-1.774, p < .001) count and HU value (OR 1.304, 95%CI: 1.149-1.479, p < .001) could independently predict the occurrence of DCI. However, only these patients with both WBC count and HU value exceeding the cut-off points (OR 36.89, 95%CI: 5.606-242.78, p < .001) were strongly correlated with DCI. Compared with a single WBC count (AUC 0.811, 95%CI: 0.729-0.892, p < .001) or HU value (AUC 0.869, 95%CI: 0.803-0.936, p < .001), the combined WBC-HU (AUC 0.898, 95%CI: 0.839-0.957, p < .001) demonstrated a better ability to predict the occurrence of DCI. Inspiringly, the prediction performance of these indicators outperformed the established inflammatory markers.

CONCLUSION

An early elevated WBC count and HU value could independently predict DCI occurrence between 4 and 30 days after aSAH. Furthermore, WBC count was positively correlated with HU value, and the combined WBC-HU demonstrated a superior prediction ability for DCI development compared with the individual indicator.

The influence of aneurysm morphology on the volume of hemorrhage after rupture

OBJECTIVE

Factors determining the risk of rupture of intracranial aneurysms have been extensively studied; however, little attention is paid to variables influencing the volume of bleeding after rupture. In this study the authors aimed to evaluate the impact of aneurysm morphological variables on the amount of hemorrhage.

METHODS

This was a retrospective cohort analysis of a prospectively collected data set of 116 patients presenting at a single center with subarachnoid hemorrhage due to aneurysmal rupture. A volumetric assessment of the total hemorrhage volume was performed from the initial noncontrast CT. Aneurysms were segmented and reproduced from the initial CT angiography study, and morphology indexes were calculated with a computer-assisted approach. Clinical and demographic characteristics of the patients were included in the study. Factors influencing the volume of hemorrhage were explored with univariate correlations, multiple linear regression analysis, and graphical probabilistic modeling.

RESULTS

The univariate analysis demonstrated that several of the morphological variables but only the patient's age from the clinical-demographic variables correlated (p < 0.05) with the volume of bleeding. Nine morphological variables correlated positively (absolute height, perpendicular height, maximum width, sac surface area, sac volume, size ratio, bottleneck factor, neck-to-vessel ratio, and width-to-vessel ratio) and two correlated negatively (parent vessel average diameter and the aneurysm angle). After multivariate analysis, only the aneurysm size ratio (p < 0.001) and the patient's age (p = 0.023) remained statistically significant. The graphical probabilistic model confirmed the size ratio and the patient's age as the variables most related to the total hemorrhage volume.

CONCLUSIONS

A greater aneurysm size ratio and an older patient age are likely to entail a greater volume of bleeding after subarachnoid hemorrhage.

Modified Glasgow coma scale for predicting outcome after subarachnoid hemorrhage surgery

There are many grading scales that attempt to predict outcome following aneurysmal subarachnoid hemorrhage (aSAH). Most scales used to assess outcome are based on the neurological status of the patient. Here, we propose a new scale for aSAH patients that combines the Glasgow Coma Scale (GCS) and the modified Fisher scale (mFS).Five hundred ninety-seven patients with aSAH who were treated at our institution between January 2008 and December 2017 were retrospectively analyzed. Initial GCS score, Hunt and Hess scale, World Federation of Neurosurgical Societies scale, mFS, and modified Rankin Scale were obtained by reviewing data. Incidence of vasospasm was investigated. Factors found to be significant on a multivariable regression analysis were used to develop a scale that was compared with other grading systems using the area under the curve (AUC) calculated from receiver operating characteristic curve.The GCS score and mFS were related to outcomes in patients with aSAH. A simple score, which we call the GCS-F score, was calculated using these initial data. The GCS-F score had an AUC of 90.5% for unfavorable outcome prediction, and 88.4% for in-hospital mortality prediction. On the receiver operating characteristic curve analysis for vasospasm, the AUC for World Federation of Neurosurgical Societies, mFS and GCS-F scores were 0.912, 0.704, and 0.936, respectively.A simple arithmetic combination of the GCS score and mFS, the GCS-F score, includes the radiographic status as well as the clinical status of the patient, so that the state of the patient can be known in more detail than other single scales. The GCS-F score may be a useful scale for predicting outcome and the occurrence of vasospasm in patients with aSAH.

When the Blood Hits Your Brain: The Neurotoxicity of Extravasated Blood

Hemorrhage in the central nervous system (CNS), including intracerebral hemorrhage (ICH), intraventricular hemorrhage (IVH), and aneurysmal subarachnoid hemorrhage (aSAH), remains highly morbid. Trials of medical management for these conditions over recent decades have been largely unsuccessful in improving outcome and reducing mortality. Beyond its role in creating mass effect, the presence of extravasated blood in patients with CNS hemorrhage is generally overlooked. Since trials of surgical intervention to remove CNS hemorrhage have been generally unsuccessful, the potent neurotoxicity of blood is generally viewed as a basic scientific curiosity rather than a clinically meaningful factor. In this review, we evaluate the direct role of blood as a neurotoxin and its subsequent clinical relevance. We first describe the molecular mechanisms of blood neurotoxicity. We then evaluate the clinical literature that directly relates to the evacuation of CNS hemorrhage. We posit that the efficacy of clot removal is a critical factor in outcome following surgical intervention. Future interventions for CNS hemorrhage should be guided by the principle that blood is exquisitely toxic to the brain.

Volumetric quantification of aneurysmal subarachnoid hemorrhage independently predicts hydrocephalus and seizures

OBJECTIVE

Hydrocephalus and seizures greatly impact outcomes of patients with aneurysmal subarachnoid hemorrhage (aSAH); however, reliable tools to predict these outcomes are lacking. The authors used a volumetric quantitative analysis tool to evaluate the association of total aSAH volume with the outcomes of shunt-dependent hydrocephalus and seizures.

METHODS

Total hemorrhage volume following aneurysm rupture was retrospectively analyzed on presentation CT imaging using a custom semiautomated computer program developed in MATLAB that employs intensity-based k-means clustering to automatically separate blood voxels from other tissues. Volume data were added to a prospectively maintained aSAH database. The association of hemorrhage volume with shunted hydrocephalus and seizures was evaluated through logistic regression analysis and the diagnostic accuracy through analysis of the area under the receiver operating characteristic curve (AUC).

RESULTS

The study population comprised 288 consecutive patients with aSAH. The mean total hemorrhage volume was 74.9 ml. Thirty-eight patients (13.2%) developed seizures. The mean hemorrhage volume in patients who developed seizures was significantly higher than that in patients with no seizures (mean difference 17.3 ml, p = 0.01). In multivariate analysis, larger hemorrhage volume on initial CT scan and hemorrhage volume > 50 ml (OR 2.81, p = 0.047, 95% CI 1.03-7.80) were predictive of seizures. Forty-eight patients (17%) developed shunt-dependent hydrocephalus. The mean hemorrhage volume in patients who developed shunt-dependent hydrocephalus was significantly higher than that in patients who did not (mean difference 17.2 ml, p = 0.006). Larger hemorrhage volume and hemorrhage volume > 50 ml (OR 2.45, p = 0.03, 95% CI 1.08-5.54) were predictive of shunt-dependent hydrocephalus. Hemorrhage volume had adequate discrimination for the development of seizures (AUC 0.635) and shunted hydrocephalus (AUC 0.629).

CONCLUSIONS

Hemorrhage volume is an independent predictor of seizures and shunt-dependent hydrocephalus in patients with aSAH. Further evaluation of aSAH quantitative volumetric analysis may complement existing scales used in clinical practice and assist in patient prognostication and management.

Acute platelet response to aneurysmal subarachnoid hemorrhage depends on severity and distribution of bleeding: an observational cohort study

Microthrombosis after aneurysmal subarachnoid hemorrhage (aSAH) is considered to initiate neuroinflammation, vessel remodeling, and blood-brain barrier leakage. We aimed to verify the hypothesis that the intensity of thrombogenicity immediately after aSAH depends on the amount and distribution of extravasated blood. This observational cohort study included 37 consecutive aSAH patients admitted no longer than 24 h after ictus. Volumes of subarachnoid and intraventricular hemorrhages as well as the Subarachnoid Hemorrhage Early Brain Edema Scale (SEBES) score were calculated in each case. Platelet system status was described by platelet count (PLT), mean platelet volume (MPV), MPV to PLT ratio, and platelet-large cell ratio (P-LCR). Median hemorrhage volume amounted to 11.4 ml (interquartile range 2.8-26.8 ml). Patients with more severe hemorrhage had lower PLT and higher MPV to PLT ratio (ρ =  - 0.49, p < .002; ρ = 0.50, p < .002, respectively). PLT decreased by 2.80 G/l per 1 ml of hemorrhage volume (95% CL 1.30-4.30, p < .001). Further analysis revealed that intraventricular hemorrhage volume was associated with P-LCR and MPV (ρ = 0.34, p < .039; ρ = 0.33, p < .048, respectively), whereas SAH volume with PLT and MPV:PLT ratio (ρ =  - 0.40, p < .013; ρ = 0.41, p < .013, respectively). The odds of unfavorable neurological outcome increased 3.95 times per 1 fl of MPV (95% CI 1.19-13.12, p < .025). MPV was independently correlated with SEBES (ρ = 0.44, p < .006). This study demonstrated that the extent and distribution of aneurysmal subarachnoid hemorrhage are related to different types of acute platelet response, which may be interpreted as local and systemic thrombogenicity. Increased mean platelet volume measured in the acute phase of aSAH may identify patients at risk for unfavorable neurological outcomes and may serve as a marker of early brain injury.

The Modified Fisher Scale Lacks Interrater Reliability

BACKGROUND

The modified Fisher scale (mFS) is a critical clinical and research tool for risk stratification of cerebral vasospasm. As such, the mFS is included as a common data element by the National Institute of Neurological Disorders and Stroke SAH Working Group. There are few studies assessing the interrater reliability of the mFS.

METHODS

We distributed a survey to a convenience sample with snowball sampling of practicing neurointensivists and through the research survey portion of the Neurocritical Care Society Web site. The survey consisted of 15 scrollable CT scans of patients with SAH for mFS grading, two questions regarding the definitions of the scale criteria and demographics of the responding physician. Kendall's coefficient of concordance was used to determine the interrater reliability of mFS grading.

RESULTS

Forty-six participants (97.8% neurocritical care fellowship trained, 78% UCNS-certified in neurocritical care, median 5 years (IQR 3-6.3) in practice, treating median of 80 patients (IQR 50-100) with SAH annually from 32 institutions) completed the survey. By mFS criteria, 30% correctly identified that there is no clear measurement of thin versus thick blood, and 42% correctly identified that blood in any ventricle is scored as "intraventricular blood." The overall interrater reliability by Kendall's coefficient of concordance for the mFS was moderate (W = 0.586, p < 0.0005).

CONCLUSIONS

Agreement among raters in grading the mFS is only moderate. Online training tools could be developed to improve mFS reliability and standardize research in SAH.

Risk Factors for Higher Volume of Hemorrhage in Ruptured Anterior Circulation Intracranial Aneurysms

Purpose: To explore the influencing factors of volume hemorrhage in ruptured anterior circulation aneurysms, so as to identify the characteristics of anterior circulation aneurysms with high volume of hemorrhage, and to provide advice for clinical diagnosis and treatment for those aneurysms. Methods: We retrospectively reviewed 437 cases of ruptured anterior intracranial aneurysms in our center between the years 2012 and 2017. According to the inclusion criteria, a total of 100 qualified patients were screened out. We collected demographic characteristics, environmental exposure, and admission status of enrolled patients. In addition, morphological parameters and location of aneurysms were also included. The semiautomatic threshold method was used to measure the volume of hemorrhage. According to the results, the patients were divided into the group with high blood volume and low blood volume. Univariate and multivariate logistic regression analyses were used to discover the related factors affecting the bleeding volume. Results: In univariable analysis, pulse pressure (P = 0.014) showed a significant difference at the P < 0.05 test level. In terms of aneurysm morphology, the irregular shape (P < 0.001), calcification (P = 0.001), and flow angle (P = 0.006) showed significant statistical differences between the two groups at the P < 0.01 level (P < 0.01). Multivariate logistic regression analysis showed that irregular shape (OR = 5.370 P = 0.002 < 0.05), large flow angle (OR = 1.033 P = 0.016 < 0.05), and calcification (OR = 5.460 P = 0.003 < 0.05) were risk factors for volume of hemorrhage in ruptured anterior circulation aneurysms. The influence of hypertension history was at critical state (OR = 2.877 P = 0.051 > 005). Conclusions: According to our analysis results, intracranial anterior circulation aneurysms with irregular shapes, calcifications, and large flow angle are more dangerous. Aneurysms with these characteristics often have a large amount of hemorrhage, requiring timely treatment in clinical practice.

Neurostereologic Lesion Volumes and Spreading Depolarizations in Severe Traumatic Brain Injury Patients: A Pilot Study

BACKGROUND

Spreading depolarizations (SDs) occur in 50-60% of patients after surgical treatment of severe traumatic brain injury (TBI) and are independently associated with unfavorable outcomes. Here we performed a pilot study to examine the relationship between SDs and various types of intracranial lesions, progression of parenchymal damage, and outcomes.

METHODS

In a multicenter study, fifty patients (76% male; median age 40) were monitored for SD by continuous electrocorticography (ECoG; median duration 79 h) following surgical treatment of severe TBI. Volumes of hemorrhage and parenchymal damage were estimated using unbiased stereologic assessment of preoperative, postoperative, and post-ECoG serial computed tomography (CT) studies. Neurologic outcomes were assessed at 6 months by the Glasgow Outcome Scale-Extended.

RESULTS

Preoperative volumes of subdural and subarachnoid hemorrhage, but not parenchymal damage, were significantly associated with the occurrence of SDs (P's < 0.05). Parenchymal damage increased significantly (median 34 ml [Interquartile range (IQR) - 2, 74]) over 7 (5, 8) days from preoperative to post-ECoG CT studies. Patients with and without SDs did not differ in extent of parenchymal damage increase [47 ml (3, 101) vs. 30 ml (- 2, 50), P = 0.27], but those exhibiting the isoelectric subtype of SDs had greater initial parenchymal damage and greater increases than other patients (P's < 0.05). Patients with temporal clusters of SDs (≥ 3 in 2 h; n = 10 patients), which included those with isoelectric SDs, had worse outcomes than those without clusters (P = 0.03), and parenchymal damage expansion also correlated with worse outcomes (P = 0.01). In multivariate regression with imputation, both clusters and lesion expansion were significant outcome predictors.

CONCLUSIONS

These results suggest that subarachnoid and subdural blood are important primary injury factors in provoking SDs and that clustered SDs and parenchymal lesion expansion contribute independently to worse patient outcomes. These results warrant future prospective studies using detailed quantification of TBI lesion types to better understand the relationship between anatomic and physiologic measures of secondary injury.

Magnesium and Hemorrhage Volume in Patients With Aneurysmal Subarachnoid Hemorrhage

OBJECTIVES

We tested the hypothesis that admission serum magnesium levels are associated with extent of hemorrhage in patients with aneurysmal subarachnoid hemorrhage.

DESIGN

Single-center prospective observational study.

SETTING

Tertiary hospital neurologic ICU.

PATIENTS

Patients with aneurysmal subarachnoid hemorrhage.

INTERVENTIONS

Clinically indicated CT scans and serum laboratory studies.

MEASUREMENTS AND MAIN RESULTS

Demographic, clinical, laboratory, and radiographic data were analyzed. Extent of initial hemorrhage was graded semi-quantitatively on admission CT scans using the modified Fisher scale (grades: 0, no radiographic hemorrhage; 1, thin [< 1 mm in depth] subarachnoid hemorrhage; 2, thin subarachnoid hemorrhage with intraventricular hemorrhage; 3, thick [≥ 1 mm] subarachnoid hemorrhage; 4, thick subarachnoid hemorrhage with intraventricular hemorrhage). We used both ordinal (modified Fisher scale) and dichotomized (thick vs thin subarachnoid hemorrhage) univariate and adjusted logistic regression models to assess associations between serum magnesium and radiographic subarachnoid hemorrhage severity. Data from 354 patients (mean age 55 ± 14 yr, 28.5% male, median admission Glasgow Coma Scale 14 [10-15]) were analyzed. Mean magnesium was lower in patients with thick versus thin subarachnoid hemorrhage (1.92 vs 1.99 mg/dL; p = 0.022). A monotonic trend across categories of modified Fisher scale was found using analysis of variance and Spearman rank correlation (p = 0.015 and p = 0.008, respectively). In adjusted ordinal and binary regression models, lower magnesium levels were associated with higher modified Fisher scale (odds ratio 0.33 per 1 mg/dL increase; 95% CI, 0.14-0.77; p = 0.011) and with thick subarachnoid hemorrhage (odds ratio 0.29 per 1 mg/dL increase; 95% CI, 0.10-0.78; p = 0.015).

CONCLUSIONS

These data support the hypothesis that magnesium influences hemorrhage severity in patients with aneurysmal subarachnoid hemorrhage, potentially through a hemostatic mechanism.

Association of Cerebrospinal Fluid Volume with Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage: A Retrospective Volumetric Analysis

BACKGROUND

In aneurysmal subarachnoid hemorrhage (SAH), clot volume has been shown to correlate with the development of radiographic vasospasm (VS), while the role of cerebrospinal fluid (CSF) volume remains largely elusive in the literature. We evaluated CSF volume as a potential surrogate for VS in addition to SAH volume in this retrospective series.

PATIENTS AND METHODS

From a consecutive cohort of aneurysmal SAH (n= 320), cases were included when angiographic evaluation for VS was performed (n= 125). SAH and CSF volumes were volumetrically quantified using an algorithm-assisted segmentation approach on initial computed tomography after ictus. Association with VS was analyzed using regression analysis. Receiver operating characteristic (ROC) curves were used to evaluate predictive accuracy of volumetric measures for VS and to identify cutoffs for risk stratification.

RESULTS

Among 125 included cases, angiography showed VS in 101 (VS+), while no VS was observed in 24 (VS-) cases. In volumetric analysis, mean SAH volume was significantly larger (26.8 ± 21.1 ml vs. 12.6 ± 12.2 ml, p= 0.001), while mean CSF volume was significantly smaller (63.0 ± 31.2 ml vs. 85.7 ± 62.8, p= 0.03) in VS+ compared to VS- cases, respectively. The absence of correlation for SAH and CSF volumes (Pearson R - 0.05, p= 0.58) indicated independence of both measures of the subarachnoid compartment, which was a prerequisite for CSF to act as a new surrogate for VS not related to SAH. Regression analysis confirmed an increased risk of VS with increasing SAH (OR 1.06, 95% CI 1.02-1.11, p= 0.006), while CSF had a protective effect toward VS (OR 0.99, 95% CI 0.98-0.99, p= 0.02). SAH/CSF ratio was also associated with VS (OR 1.03, 95% CI 1.01-1.05, p= 0.015). ROC curves suggested cutoffs at 120 ml CSF and 20 ml SAH for VS stratification. Combination of variables improved stratification accuracy compared to use of SAH alone.

CONCLUSION

This study provides a proof of concept for CSF correlating with angiographic VS after aneurysmal SAH. Quantification of CSF in conjunction with SAH might enhance risk stratification and exhibit advantages over traditional scores. The association of CSF has to be corroborated for delayed cerebral ischemia to further establish CSF as a surrogate parameter.

The role of haptoglobin and hemopexin in the prevention of delayed cerebral ischaemia after aneurysmal subarachnoid haemorrhage: a review of current literature

Delayed cerebral ischaemia (DCI) after aneurysmal subarachnoid haemorrhage (aSAH) is a major cause of mortality and morbidity. The pathophysiology of DCI after aSAH is thought to involve toxic mediators released from lysis of red blood cells within the subarachnoid space, including free haemoglobin and haem. Haptoglobin and hemopexin are endogenously produced acute phase proteins that are involved in the clearance of these toxic mediators. The aim of this review is to investigate the pathophysiological mechanisms involved in DCI and the role of both endogenous as well as exogenously administered haptoglobin and hemopexin in the prevention of DCI.

Early prediction of clinical outcomes in patients with aneurysmal subarachnoid hemorrhage using computed tomography texture analysis

Radiological evaluation of subarachnoid hemorrhage (SAH) is often subject to interobserver variability. The aim of this study was to retrospectively detect computed tomography (CT) texture parameters in the early postictal state to predict cerebral vasospasm, delayed cerebral ischemia (DCI), and functional outcome in aneurysmal SAH using quantitative CT texture analysis (CTTA) via a commercially available software program and routine CT images. 40 patients with aneurysmal SAH surgically treated at the Keio University Hospital during a four-year period were analyzed. CT texture analyses were performed using a commercially available software program (Synapse Vincent). The following texture parameters of blood clots in the subarachnoid space and cerebral edema were assessed: mean CT value, entropy, skewness, and kurtosis. The mean CT value of blood clots in the subarachnoid space was significantly associated with cerebral vasospasm, DCI, and functional outcome. The mean CT value ≥ 49.64 Hounsfield units (HU) predicted cerebral vasospasm with a sensitivity and specificity of 85.7% and 61.5%, respectively (area under the curve [AUC] = 0.758). The mean CT value ≥ 49.95 HU predicted DCI with a sensitivity and specificity of 100% and 60.6%, respectively (AUC = 0.810). The mean CT value ≥ 53.00 HU predicted poor functional outcome with a sensitivity and specificity of 56.3% and 91.7%, respectively (AUC = 0.747). CTTA using a commercially available software program demonstrated that the mean CT value of clots in the subarachnoid space in the early postictal state could predict vasospasm, DCI, and clinical outcome with a high sensitivity and specificity.

Small ruptured intracranial aneurysms: the risk of massive bleeding and rebleeding

OBJECTIVE

The risk of hemorrhagic events in small ruptured aneurysms remains unclear. Due to less arterial wall, small ruptured aneurysms may be correlated with massive bleeding and rebleeding. Therefore, it may contribute to treatment to evaluate the amount of bleeding and the risk of rebleeding in small ruptured aneurysms.

METHODS

A retrospective cohort study of all consecutive patients with intracranial aneurysms admitted to our hospital from February 2013 to December 2017 was carried out. Ruptured aneurysms were divided into small ruptured aneurysm (0-5 mm) group and large ruptured aneurysm (5 mm) group for analysis. The difference of bleeding volume, rebleeding and clinical outcome were analyzed between the two groups.

RESULTS

A total of 738 patients with aneurysmal subarachnoid hemorrhage (SAH) were included in this study and small ruptured aneurysms accounted for 49.2% of all ruptured aneurysms. Univariate analysis showed that the amount of bleeding (14.5 ± 7.1 vs. 14.4 ± 7.3; P = 0.867), rebleeding (8.3% vs. 10.9%; P = 0.261) and poor outcome (29.6% vs. 23.1%; P = 0.055) were similar between the two groups. Multivariable analysis showed that hypertension was obviously associated with the amount of bleeding (adjusted odds ratio (aOR), 3.25 [1.81-4.69]; P < 0.001) and rebleeding (aOR, 3.31 [1.10-9.99]; P = 0.034) in small ruptured aneurysms, and its effect on rebleeding of small ruptured aneurysms is greater than that of large ruptured aneurysms.

CONCLUSIONS

The risk of hemorrhagic events in small ruptured aneurysms is similar to that in large ruptured aneurysms, especially those patients with small ruptured aneurysms that complicated with hypertension are at an increased risk of massive SAH and rebleeding.

Early focal brain injury after subarachnoid hemorrhage correlates with spreading depolarizations

OBJECTIVE

To investigate whether spreading depolarization (SD)-related variables at 2 different time windows (days 1-4 and 5-8) after aneurysmal subarachnoid hemorrhage (aSAH) correlate with the stereologically determined volume of early focal brain injury on the preinterventional CT scan.

METHODS

In this observational multicenter study of 54 patients, volumes of unaffected brain tissue, ventricles, cerebellum, aSAH, intracerebral hemorrhage, and focal parenchymal hypodensity were stereologically estimated. Patients were electrocorticographically monitored using subdural electrodes for 81.8 hours (median) (interquartile range: 70.6-90.5) during days 1-4 (n = 54) and for 75.9 (59.5-88.7) hours during days 5-8 (n = 51). Peak total SD-induced depression duration of a recording day (PTDDD) and peak numbers of (1) SDs, (2) isoelectric SDs, and (3) spreading depressions of a recording day were determined following the recommendations of the Co-Operative Studies on Brain Injury Depolarizations.

RESULTS

Thirty-three of 37 patients with early focal brain injury (intracerebral hemorrhage and/or hypodensity) in contrast to 7 of 17 without displayed SDs during days 1-4 (sensitivity: 89% [95% confidence interval, CI: 75%-97%], specificity: 59% [CI: 33%-82%], positive predictive value: 83% [CI: 67%-93%], negative predictive value: 71% [CI: 42%-92%], Fisher exact test, p < 0.001). All 4 SD-related variables during days 1-4 significantly correlated with the volume of early focal brain injury (Spearman rank order correlations). A multiple ordinal regression analysis identified the PTDDD as the most important predictor.

CONCLUSIONS

Our findings suggest that early focal brain injury after aSAH is associated with early SDs and further support the notion that SDs are a biomarker of focal brain lesions.

Quantitative versus qualitative blood amount assessment as a predictor for shunt-dependent hydrocephalus following aneurysmal subarachnoid hemorrhage

OBJECTIVE

Reliable tools are lacking to predict shunt-dependent hydrocephalus (SDHC) development after aneurysmal subarachnoid hemorrhage (aSAH). Quantitative volumetric measurement of hemorrhagic blood is a good predictor of SDHC but might be impractical in the clinical setting. Qualitative assessment performed using scales such as the modified Fisher scale (mFisher) and the original Graeb scale (oGraeb) is easier to conduct but provides limited predictive power. In between, the modified Graeb scale (mGraeb) keeps the simplicity of the qualitative scales yet adds assessment of acute hydrocephalus, which might improve SDHC-predicting capabilities. In this study the authors investigated the likely capabilities of the mGraeb and compared them with previously validated methods. This research also aimed to define a tailored mGraeb cutoff point for SDHC prediction.

METHODS

The authors performed retrospective analysis of patients admitted to their institution with the diagnosis of aSAH between May 2013 and April 2016. Out of 168 patients, 78 were included for analysis after the application of predefined exclusion criteria. Univariate and multivariate analyses were conducted to evaluate the use of all 4 methods (quantitative volumetric assessment and the mFisher, oGraeb, and mGraeb scales) to predict the likelihood of SDHC development based on clinical data and blood amount assessment on initial CT scans.

RESULTS

The mGraeb scale was demonstrated to be the most robust predictor of SDHC, with an area under the curve (AUC) of 0.848 (95% CI 0.763-0.933). According to the AUC results, the performance of the mGraeb scale was significantly better than that of the oGraeb scale (χ2 = 4.49; p = 0.034) and mFisher scale (χ2 = 7.21; p = 0.007). No statistical difference was found between the AUCs of the mGraeb and the quantitative volumetric measurement models (χ2 = 12.76; p = 0.23), but mGraeb proved to be the simplest model since it showed the lowest Akaike information criterion (66.4), the lowest Bayesian information criterion (71.2), and the highest R2Nagelkerke coefficient (39.7%). The initial mGraeb showed more than 85% specificity for predicting the development of SDHC in patients presenting with a score of 12 or more points.

CONCLUSIONS

According to the authors' data, the mGraeb scale is the simplest model that correlates well with SDHC development. Due to limited scientific evidence of treatments aimed at SDHC prevention, we propose an mGraeb score higher than 12 to identify patients at risk with high specificity. This mGraeb cutoff point might also serve as a useful prognostic tool since patients with SDHC after aSAH have worse functional outcomes.

Radiological Estimation of Intracranial Blood Volume and Occurrence of Hydrocephalus Determines Stress-Induced Hyperglycemia After Aneurysmal Subarachnoid Hemorrhage

Acute phase after aneurysmal subarachnoid hemorrhage (aSAH) is associated with several metabolic derangements including stress-induced hyperglycemia (SIH). The present study is designed to identify objective radiological determinants for SIH to better understand its contributory role in clinical outcomes after aSAH. A computer-aided detection tool was used to segment admission computed tomography (CT) images of aSAH patients to estimate intracranial blood and cerebrospinal fluid volumes. Modified Graeb score (mGS) was used as a semi-quantitative measure to estimate degree of hydrocephalus. The relationship between glycemic gap (GG) determined SIH, mGS, and estimated intracranial blood and cerebrospinal fluid volumes were evaluated using linear regression. Ninety-four [94/187 (50.3%)] among the study cohort had SIH (defined as GG > 26.7 mg/dl). Patients with SIH had 14.3 ml/1000 ml more intracranial blood volume as compared to those without SIH [39.6 ml (95% confidence interval, CI, 33.6 to 45.5) vs. 25.3 ml (95% CI 20.6 to 29.9), p = 0.0002]. Linear regression analysis of mGS with GG showed each unit increase in mGS resulted in 1.2 mg/dl increase in GG [p = 0.002]. Patients with SIH had higher mGS [median 4.0, interquartile range, IQR 2.0-7.0] as compared to those without SIH [median 2.0, IQR 0.0-6.0], p = 0.002. Patients with third ventricular blood on admission CT scan were more likely to develop SIH [67/118 (56.8%) vs. 27/69 (39.1%), p = 0.023]. Hence, the present study, using unbiased SIH definition and objective CT scan parameters, reports "dose-dependent" radiological features resulting in SIH. Such findings allude to a brain injury-stress response-neuroendocrine axis in etiopathogenesis of SIH.

Quantification of Cerebral Edema After Subarachnoid Hemorrhage

BACKGROUND

Global cerebral edema (GCE) is a manifestation of early brain injury (EBI) after subarachnoid hemorrhage (SAH) and is an independent risk factor for poor outcome. The lack of a quantitative method to measure GCE limits the study of its pathophysiology. The goal of this study is to develop a quantitative surrogate marker that represents GCE after SAH.

METHODS

Patients with spontaneous SAH were enrolled into a prospective observational database. Initial CT scans were graded for GCE using established qualitative criteria. Selective sulcal volume (SSV) was defined as total mL of sulcal volumes on axial CT slices above the most cranial section of the lateral ventricles to the last visible section. Using a semiautomatic threshold approach, sulcal regions were traced out with manual adjustments when necessary. The volume of sulci in each slice was calculated and multiplied by the slice thickness and number of slices to calculate the SSV. All volumetric analysis was performed using Medical Image Processing, Analysis and Visualization Version 7.0.1 (MIPAV).

RESULTS

A total of 109 subjects were included in our analysis. Mean selective sulcal volumes (SSV) differed between subjects with and without GCE 4.5 and 21.2 mL (P < 0.001). When separated into quartiles, the odds of qualitative GCE increases as SSV decreases. Compared to the highest SSV quartile, smaller SSV was associated with worse clinical outcomes.

CONCLUSION

GCE can be quantified using volumetric analysis of SSV measurements on routine CT scans. Smaller SSV on admission is predictive of worse clinical outcomes. SSV may be an important marker of EBI after SAH.

Rater Reliability of the Hardy Classification for Pituitary Adenomas in the Magnetic Resonance Imaging Era

Objectives  The Hardy classification is used to classify pituitary tumors for clinical and research purposes. The scale was developed using lateral skull radiographs and encephalograms, and its reliability has not been evaluated in the magnetic resonance imaging (MRI) era. Design  Fifty preoperative MRI scans of biopsy-proven pituitary adenomas using the sellar invasion and suprasellar extension components of the Hardy scale were reviewed. Setting  This study was a cohort study set at a single institution. Participants  There were six independent raters. Main Outcome Measures  The main outcome measures of this study were interrater reliability, intrarater reliability, and percent agreement. Results  Overall interrater reliability of both Hardy subscales on MRI was strong. However, reliability of the intermediate scores was weak, and percent agreement among raters was poor (12-16%) using the full scales. Dichotomizing the scale into clinically useful groups maintained strong interrater reliability for the sellar invasion scale and increased the percent agreement for both scales. Conclusion  This study raises important questions about the reliability of the original Hardy classification. Editing the measure to a clinically relevant dichotomous scale simplifies the rating process and may be useful for preoperative tumor characterization in the MRI era. Future research studies should use the dichotomized Hardy scale (sellar invasion Grades 0-III versus Grade IV, suprasellar extension Types 0-C versus Type D).

Interrater and intrarater reliability of the Knosp scale for pituitary adenoma grading

OBJECTIVE

The goal of this study was to determine the interrater and intrarater reliability of the Knosp grading scale for predicting pituitary adenoma cavernous sinus (CS) involvement.

METHODS

Six independent raters (3 neurosurgery residents, 2 pituitary surgeons, and 1 neuroradiologist) participated in the study. Each rater scored 50 unique pituitary MRI scans (with contrast) of biopsy-proven pituitary adenoma. Reliabilities for the full scale were determined 3 ways: 1) using all 50 scans, 2) using scans with midrange scores versus end scores, and 3) using a dichotomized scale that reflects common clinical practice. The performance of resident raters was compared with that of faculty raters to assess the influence of training level on reliability.

RESULTS

Overall, the interrater reliability of the Knosp scale was “strong” (0.73, 95% CI 0.56–0.84). However, the percent agreement for all 6 reviewers was only 10% (26% for faculty members, 30% for residents). The reliability of the middle scores (i.e., average rated Knosp Grades 1 and 2) was “very weak” (0.18, 95% CI −0.27 to 0.56) and the percent agreement for all reviewers was only 5%. When the scale was dichotomized into tumors unlikely to have intraoperative CS involvement (Grades 0, 1, and 2) and those likely to have CS involvement (Grades 3 and 4), the reliability was “strong” (0.60, 95% CI 0.39–0.75) and the percent agreement for all raters improved to 60%. There was no significant difference in reliability between residents and faculty (residents 0.72, 95% CI 0.55–0.83 vs faculty 0.73, 95% CI 0.56–0.84). Intrarater reliability was moderate to strong and increased with the level of experience.

CONCLUSIONS

Although these findings suggest that the Knosp grading scale has acceptable interrater reliability overall, it raises important questions about the “very weak” reliability of the scale's middle grades. By dichotomizing the scale into clinically useful groups, the authors were able to address the poor reliability and percent agreement of the intermediate grades and to isolate the most important grades for use in surgical decision making (Grades 3 and 4). Authors of future pituitary surgery studies should consider reporting Knosp grades as dichotomized results rather than as the full scale to optimize the reliability of the scale.

The Hijdra scale has significant prognostic value for the functional outcome of Fisher grade 3 patients with subarachnoid hemorrhage

PURPOSE

Despite its high prevalence among patients with aneurysmal subarachnoid hemorrhage (aSAH) and high risk of delayed cerebral ischemia (DCI), the Fisher grade 3 category remains a poorly studied subgroup. The aim of this cohort study has been to investigate the prognostic value of the Hijdra sum scoring system for the functional outcome in patients with Fisher grade 3 aSAH, in order to improve the risk stratification within this Fisher category.

METHODS

Initial CT scans of 72 prospectively enrolled patients with Fisher grade 3 aSAH were analyzed, and cisternal, ventricular, and total amount of blood were graded according to the Hijdra scale. Additionally, space-occupying subarachnoid blood clots were assessed. Outcome was evaluated after 6 months.

RESULTS

Within the subgroup of Fisher grade 3, aSAH patients with an unfavorable outcome showed a significantly larger cisternal Hijdra sum score (HSS: 21.1 ± 5.2) than patients with a favorable outcome (HSS: 17.6 ± 5.9; p = 0.009). However, both the amount of ventricular blood (p = 0.165) and space-occupying blood clots (p = 0.206) appeared to have no prognostic relevance. After adjusting for the patient's age, gender, tobacco use, clinical status at admission, and presence of intracerebral hemorrhage, the cisternal and total HSS remained the only independent parameters included in multivariate logistic regression models to predict functional outcome (p < 0.01).

CONCLUSION

The cisternal Hijdra score is fairly easy to perform and the present study indicates that it has an additional predictive value for the functional outcome within the Fisher 3 category. We suggest that the Hijdra scale is a practically useful prognostic instrument for the risk evaluation after aSAH and should be applied more often in the clinical setting.

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.

The VASOGRADE: A Simple Grading Scale for Prediction of Delayed Cerebral Ischemia After Subarachnoid Hemorrhage

BACKGROUND AND PURPOSE

Patients are classically at risk of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage. We validated a grading scale-the VASOGRADE-for prediction of DCI.

METHODS

We used data of 3 phase II randomized clinical trials and a single hospital series to assess the relationship between the VASOGRADE and DCI. The VASOGRADE derived from previously published risk charts and consists of 3 categories: VASOGRADE-Green (modified Fisher scale 1 or 2 and World Federation of Neurosurgical Societies scale [WFNS] 1 or 2); VASOGRADE-Yellow (modified Fisher 3 or 4 and WFNS 1-3); and VASOGRADE-Red (WFNS 4 or 5, irrespective of modified Fisher grade). The relation between the VASOGRADE and DCI was assessed by logistic regression models. The predictive accuracy of the VASOGRADE was assessed by receiver operating characteristics curve and calibration plots.

RESULTS

In a cohort of 746 patients, the VASOGRADE significantly predicted DCI (P<0.001). The VASOGRADE-Yellow had a tendency for increased risk for DCI (odds ratio [OR], 1.31; 95% CI, 0.77-2.23) when compared with VASOGRADE-Green; those with VASOGRADE-Red had a 3-fold higher risk of DCI (OR, 3.19; 95% CI, 2.07-4.50). Studies were not a significant confounding factor between the VASOGRADE and DCI. The VASOGRADE had an adequate discrimination for prediction of DCI (area under the receiver operating characteristics curve=0.63) and good calibration.

CONCLUSIONS

The VASOGRADE results validated previously published risk charts in a large and diverse sample of subarachnoid hemorrhage patients, which allows DCI risk stratification on presentation after subarachnoid hemorrhage. It could help to select patients at high risk of DCI, as well as standardize treatment protocols and research studies.