Trends in hospitalization and mortality for subarachnoid hemorrhage and unruptured aneurysms in the United States

Trends in the Age of Patients Treated for Unruptured Intracranial Aneurysms from 1990 to 2020

BACKGROUND

The decision for treatment for unruptured intracranial aneurysms (UIAs) is often difficult. Innovation in endovascular devices have improved the benefit-to-risk profile especially for elderly patients; however, the treatment guidelines from the past decade often recommend conservative management. It is unknown how these changes have affected the overall age of the patients selected for treatment. Herein, we aimed to study potential changes in the average age of the patients that are being treated over time.

METHODS

A systematic search of the literature was performed to identify all studies describing the age of the UIAs that were treated by any modality. Scatter diagrams with trend lines were used to plot the age of the patients treated over time and assess the presence of a potential significant trend via statistical correlation tests.

RESULTS

A total of 280 studies including 83,437 UIAs treated between 1987 and 2021 met all eligibility criteria and were entered in the analysis. Mean age of the patients was 55.5 years, and 70.7% were female. There was a significant increasing trend in the age of the treated patients over time (Spearman r: 0.250; P < 0.001), with a 1-year increase in the average age of the treated patients every 5 years since 1987.

CONCLUSIONS

The present study indicates that based on the treated UIA patient data published in the literature, older UIAs are being treated over time. This trend is likely driven by safer treatments while suggesting that re-evaluation of certain UIA treatment decision scores may be of great interest.

Association between external ventricular drain removal or replacement and prophylactic anticoagulation in patients with aneurysmal subarachnoid hemorrhage: a propensity-adjusted analysis

BACKGROUND

Withholding prophylactic anticoagulation from patients with aneurysmal subarachnoid hemorrhage (aSAH) before external ventricular drain (EVD) removal or replacement remains controversial. This study analyzed whether prophylactic anticoagulation was associated with hemorrhagic complications related to EVD removal.

METHOD

All aSAH patients treated from January 1, 2014, to July 31, 2019, with an EVD placed were retrospectively analyzed. Patients were compared based on the number of prophylactic anticoagulant doses withheld for EVD removal (> 1 vs. ≤ 1). The primary outcome analyzed was deep venous thrombosis (DVT) or pulmonary embolism (PE) after EVD removal. A propensity-adjusted logistic-regression analysis was performed for confounding variables.

RESULTS

A total of 271 patients were analyzed. For EVD removal, > 1 dose was withheld from 116 (42.8%) patients. Six (2.2%) patients had a hemorrhage associated with EVD removal, and 17 (6.3%) patients had a DVT or PE. No significant difference in EVD-related hemorrhage after EVD removal was found between patients with  > 1 versus ≤ 1 dose of anticoagulant withheld (4 of 116 [3.5%] vs. 2 of 155 [1.3%]; p = 0.41) or between those with no doses withheld compared to ≥ 1 dose withheld (1 of 100 [1.0%] vs. 5 of 171 [2.9%]; p = 0.32). After adjustment, withholding > 1 dose of anticoagulant versus ≤ 1 dose was associated with the occurrence of DVT or PE (OR 4.8; 95% CI, 1.5-15.7; p = 0.009).

CONCLUSIONS

In aSAH patients with EVDs, withholding > 1 dose of prophylactic anticoagulant for EVD removal was associated with an increased risk of DVT or PE and no reduction in catheter removal-associated hemorrhage.

Small intracranial aneurysms of the anterior circulation: A negligible risk?

BACKGROUND AND PURPOSE

According to the International Study of Unruptured Intracranial Aneurysms, small (<7 mm) unruptured intracranial aneurysms (IAs) of the anterior circulation (aC) carry a neglectable 5-year rupture risk. In contrast, some studies report frequencies of >20% of all ruptured IAs being small IAs of the aC. This contradiction was addressed in this study by analyzing the rates and risk factors for rupture of small IAs within the aC.

METHODS

Of the institutional observational cohort, 1676 small IAs of the aC were included. Different demographic, clinical, laboratory, and radiographic characteristics were collected. A rupture risk score was established using all independent prognostic factors. The score performance was checked using receiver operating characteristic curve analysis.

RESULTS

Of all registered small IAs of the aC, 20.1% were ruptured. The developed small IAs of the aC (SIAAC) score (range = -4 to +13 points) contained five major risk factors: IA location and size, arterial hypertension, alcohol abuse, and chronic renal failure. In addition, three putative protective factors were also included in the score: hypothyroidism, dyslipidemia, and peripheral arterial disease. Increasing rates of ruptured IA with increasing SIAAC scores were observed, from 0% (≤-1 points) through >50% (≥8 points) and up to 100% in patients scoring ≥12 points. The SIAAC score achieved excellent discrimination (area under the curve_SIAAC  = 0.803) and performed better than the PHASES (Population,Hypertension, Age, Size of the aneurysm, Earlier SAH from another aneurysm, Site of aneurysm) score.

CONCLUSIONS

Small IAs of the aC carry a considerable rupture risk. After external validation, the proposed rupture risk score might provide a basis for better decision-making regarding the treatment of small unruptured IAs of the aC.

Predicting the rupture status of small middle cerebral artery aneurysms using random forest modeling

Objective

Small intracranial aneurysms are increasingly being detected; however, a prediction model for their rupture is rare. Random forest modeling was used to predict the rupture status of small middle cerebral artery (MCA) aneurysms with morphological features.

Methods

From January 2009 to June 2020, we retrospectively reviewed patients with small MCA aneurysms (<7 mm). The aneurysms were randomly split into training (70%) and internal validation (30%) cohorts. Additional independent datasets were used for the external validation of 78 small MCA aneurysms from another four hospitals. Aneurysm morphology was determined using computed tomography angiography (CTA). Prediction models were developed using the random forest and multivariate logistic regression.

Results

A total of 426 consecutive patients with 454 small MCA aneurysms (<7 mm) were included. A multivariate logistic regression analysis showed that size ratio (SR), aspect ratio (AR), and daughter dome were associated with aneurysm rupture, whereas aneurysm angle and multiplicity were inversely associated with aneurysm rupture. The areas under the receiver operating characteristic (ROC) curves (AUCs) of random forest models using the five independent risk factors in the training, internal validation, and external validation cohorts were 0.922, 0.889, and 0.92, respectively. The random forest model outperformed the logistic regression model (p = 0.048). A nomogram was developed to assess the rupture of small MCA aneurysms.

Conclusion

Random forest modeling is a good tool for evaluating the rupture status of small MCA aneurysms and may be considered for the management of small aneurysms.

Analysis of Factors Related to Growth and Growth Patterns of Unruptured Intracranial Aneurysms

Objective

Methods

Results

Conclusion

Mortality among patients treated for aneurysmal subarachnoid hemorrhage in Eastern Denmark 2017-2019

OBJECTIVE

The aim of the study was to investigate (1) the 30-day, 3-month, and 12-month cumulative mortalities for patients who underwent aneurysm occlusion, and (2) the causes of death, and (3) the potential risk factors for death.

METHODS

All patients who underwent surgical clipping or endovascular treatment of a ruptured aneurysm at Copenhagen University Hospital, during the period of January 1, 2017-December 31, 2019, were included and followed up for 12 months. Data regarding vital status, causes of death, comorbidities, treatment, and clinical presentations on admission was collected. The absolute mortality risk was estimated as a function of time with a 95% confidence interval. The associations between potential risk factors and death were estimated as odds ratios with 95% confidence intervals using logistic regression models.

RESULTS

A total of 317 patients were included. The overall cumulative mortalities after 30 days, 3 months, and 12 months were 10.7%, 12.9%, and 16.1%, respectively. The most common cause of death was severe primary hemorrhage (52.9%), followed by infections (15.7%) and rebleeding (11.8%). WFNS score > 3 and Fisher score > 3 on admission, preprocedural hydrocephalus, and preprocedural rebleeding were found significantly associated with higher risk of death.

CONCLUSIONS

Considerable mortality was seen. Possible preventable causes accounted for approximately 22% of the deaths. The occurrence of both pre- and postprocedural rebleeding's indicates an opportunity of further improvement of the mortality by (1) further reduction of time from aSAH to aneurysm occlusion and (2) continuous efforts in improving methods of aneurysm occlusion.

Volumes, outcomes, and complications after surgical versus endovascular treatment of aneurysms in the United States (1993–2015): continued evolution versus steady-state after more than 2 decades of practice

OBJECTIVE

Adoption of endovascular treatment (EVT) and other advances in aneurysm care have shifted practice patterns of cerebral aneurysm treatment over the past 2 decades in the US. The objective of this study was to determine whether resulting trends in volumes, outcomes, and complications have matured in general practice or continue to evolve.

METHODS

Data were obtained from the National Inpatient Sample from 1993 to 2015. ICD-9 codes were used to estimate annual volumes, outcomes, and complications following treatment of ruptured and unruptured aneurysms. Univariate and multivariate analyses were used to estimate risk ratios for complications and outcomes. Trends in time were assessed utilizing annual percentage change (APC).

RESULTS

The authors found a nearly 5-fold increase in annual admissions with diagnoses of unruptured aneurysms, whereas SAH volume increased less than 50%. Clipping ruptured aneurysms steadily declined (APC −0.86%, p = 0.69 until 1999, then −6.22%, p < 0.001 thereafter), whereas clipping unruptured aneurysms slightly increased (APC 2.02%, p < 0.001). EVT tripled in 2002–2004 and steadily increased thereafter (APC 7.22%, p < 0.001 and 5.85%, p = 0.01 for unruptured and ruptured aneurysms, respectively). Despite a 3-fold increase in both diagnosis and treatment of unruptured aneurysms, the incidence of SAH remained steady at 12 per 100,000 persons per year (APC 0.04%, p = 0.83). In contrast, SAH severity increased over time, as did patient age and comorbidities (all p < 0.001). SAH led to nonroutine discharge more frequently over time after both EVT and clipping (APC 1.24% and 1.10%, respectively), although mortality decreased during the same time (APC −2.48% and −1.44%, respectively). Complications were more frequent after clipping than EVT, but this differential risk diminished during the study period and was less perceptible in ruptured aneurysms. The proportion of patients discharged home after treatment of unruptured aneurysms was significantly lower (p < 0.001) after clipping (69.3%–79.5%) than EVT (88.3%–93.3%); both proportions changed minimally since 1998 (APC −0.39%, p = 0.02, and APC −0.11%, p = 0.14, respectively).

CONCLUSIONS

EVT volume markedly increased for ruptured and unruptured aneurysms from 1993 to 2015, whereas clipping decreased for ruptured and slightly increased for unruptured aneurysms. The incidence of SAH remained unchanged despite increased diagnosis and treatment of unruptured aneurysms. In ruptured aneurysms, SAH severity has increased over time, as have age, comorbidities, and nonroutine discharges. In contrast, routine discharge after treatment of unruptured aneurysms remains largely unchanged since 1998 and remains lower with clipping.

Epidemiological trends of surgical admissions to the intensive care unit in the United States

BACKGROUND

Epidemiologic assessment of surgical admissions into intensive care units (ICUs) provides a framework to evaluate health care system efficiency and project future health care needs.

METHODS

We performed a 9-year (2008-2016), retrospective, cohort analysis of all adult admissions to 88 surgical ICUs using the prospectively and manually abstracted Cerner Acute Physiology and Chronic Health Evaluation Outcomes database. We stratified patients into 13 surgical cohorts and modeled temporal trends in admission, mortality, surgical ICU length of stay (LOS), and change in functional status (FS) using generalized mixed-effects and Quasi-Poisson models to obtain risk-adjusted outcomes.

RESULTS

We evaluated 78,053 ICU admissions and observed a significant decrease in admissions after transplant and thoracic surgery, with a concomitant increase in admissions after otolaryngological and facial reconstructive procedures (all p < 0.05). While overall risk-adjusted mortality remained stable over the study period; mortality significantly declined in orthopedic, cardiac, urologic, and neurosurgical patients (all p < 0.05). Cardiac, urologic, gastrointestinal, neurosurgical, and orthopedic admissions showed significant reductions in LOS (all p < 0.05). The overall rate of FS deterioration increased per year, suggesting ICU-related disability increased over the study period.

CONCLUSION

Temporal analysis demonstrates a significant change in the type of surgical patients admitted to the ICU over the last decade, with decreasing mortality and LOS in selected cohorts, but an increasing rate of FS deterioration. Improvement in ICU outcomes may highlight the success of health care advancements within certain surgical cohorts, while simultaneously identifying cohorts that may benefit from future intervention. Our findings have significant implications in health care systems planning, including resource and personnel allocation, education, and surgical training.

LEVEL OF EVIDENCE

Economic/decision, level IV.Epidemiologic, level IV.

Intra- and inter-observer variability in intracranial aneurysm segmentation: comparison between CT angiography (semi-automated segmentation software stroke VCAR) and digital subtraction angiography (3D rotational angiography)

PURPOSE

To compare size and morphologic features of three-dimensional aneurysm models, obtained with a semi-automated segmentation software (Stroke VCAR, GE, USA) from cerebral CT angiography (CTA) data, to three-dimensional aneurysm models obtained with digital subtraction angiography (DSA, with 3D rotational angiography acquisition-3DRA), considered as the reference standard.

METHODS

In this retrospective study, we reviewed 132 patients, with a total number of 137 intracranial aneurysm, who underwent CTA and subsequent DSA examination, supplemented with 3DRA. We compared neck length, short axis and long axis measured on 3DRA model to the same variables measured on 3D-CTA model by two blinded readers and to the automatic software dimensions. Therefore, statistics analysis assessed intra-observer and inter-observer variability and differences between patients with or without subarachnoid hemorrhage (SAH).

RESULTS

There were no significant differences in short-axis and long-axis measurements between 3D angiographic and 3D-CTA models, while comparison of neck lengths revealed a statistically significant difference, which tended to be greater for smaller neck lengths (partial volume effect and "kissing vessels" artifact). There were significant differences between manual and automatic data measured for the same three variables, and the presence of SAH did not affect aneurysm 3D reconstruction. Inter-observer agreement resulted moderate for neck length and substantial for short axis and long axis.

CONCLUSION

The examined 3D-CTA segmentation system is a reproducible procedure for aneurysm morphologic characterization and, in particular, for assessment of aneurysm sac dimensions, but considerable carefulness is required in neck length interpretation.

Variability of Clinical and Angiographic Results Based on the Treatment Preference (Endovascular or Surgical) of Centers Participating in the Subarachnoid Hemorrhage Database of the Working Group of the Spanish Society of Neurosurgery

OBJECTIVES

Since the introduction of endovascular treatment for cerebral aneurysms, hospitals in which subarachnoid hemorrhage is treated show different availability and/or preferences towards both treatment modalities. The main aim is to evaluate the clinical and angiographic results according to the hospital's treatment preferences applied.

METHODS

This study was conducted based on use of the subarachnoid hemorrhage database of the Vascular Pathology Group of the Spanish Neurosurgery Society. Centers were classified into 3 subtypes according to an index in the relationship between endovascular and surgical treatment as: endovascular preference, high endovascular preference, and elevated surgical preference. The clinical results and angiographic results were evaluated among the 3 treatment strategies.

RESULTS

From November 2004 to December 2017, 4282 subarachnoid hemorrhage patients were selected for the study: 630 (14.7%) patients from centers with surgical preference, 2766 (64.6%) from centers with endovascular preference, and 886 (20.7%) from centers with high endovascular preference. The surgical preference group obtained the best angiographic results associated with a greater complete exclusion (odds ratio: 1.359; 95% confidence interval: 1.025-1.801; P = 0.033). The surgical preference subgroup obtained the best outcome at discharge (65.45%), followed by the high endovascular preference group (61.5%) and the endovascular preference group (57.8%) (odds ratio: 1.359; 95% confidence interval: 1.025-1.801; P = 0.033).

CONCLUSIONS

In Spain, there is significant variability in aneurysm exclusion treatment in aneurysmal subarachnoid hemorrhage. Surgical centers offer better results for both surgical and endovascular patients. A multidisciplinary approach and the maintenance of an elevated quality of surgical competence could be responsible for these results.

Management of Tiny Unruptured Intracranial Aneurysms: A Comparative Effectiveness Analysis

Importance

Unruptured intracranial aneurysms (UIAs) are relatively common in the general population and are being increasingly diagnosed; a significant proportion are tiny (≤3 mm) aneurysms. There is significant heterogeneity in practice and lack of clear guidelines on the management of incidental, tiny UIAs. It is important to quantify the implications of different management strategies in terms of health benefits to patients.

Objective

To evaluate the effectiveness of routine treatment (aneurysm coiling) vs 3 strategies for imaging surveillance compared with no preventive treatment or routine follow-up of tiny UIAs.

Design, Setting, and Participants

A decision-analytic model-based comparative effectiveness analysis was conducted from May 1 to June 30, 2017, using inputs from the medical literature. PubMed searches were performed to identify relevant literature for all key model inputs, each of which was derived from the clinical study with the most robust data and greatest applicability. Analysis included 10 000 iterations simulating adult patients with incidental detections of UIAs 3 mm or smaller and no history of subarachnoid hemorrhage.

Interventions

The following 5 management strategies for tiny UIAs were evaluated: annual magnetic resonance angiography (MRA) screening, biennial MRA screening, MRA screening every 5 years, aneurysm coiling and follow-up, and no treatment or preventive follow-up.

Main Outcomes and Measures

A Markov decision model for lifetime rupture was constructed from a societal perspective per 10 000 patients with incidental, tiny UIAs. Outcomes were assessed in terms of quality-adjusted life-years. Probabilistic, 1-way, and 2-way sensitivity analyses were performed.

Results

In this analysis of 10 000 iterations simulating adult patients with a mean age of 50 years, the base-case calculation shows that the management strategy of no treatment or preventive follow-up has the highest health benefit (mean [SD] quality-adjusted life-years, 19.40 [0.31]). Among the management strategies that incorporate follow-up imaging, MRA every 5 years is the best strategy with the next highest effectiveness (mean [SD] quality-adjusted life-years, 18.05 [0.62]). The conclusion remains robust in probabilistic and 1-way sensitivity analyses. No routine follow-up remains the optimal strategy when the annual growth rate and risk of rupture of growing aneurysms are varied. When the annual risk of rupture of nongrowing UIAs is less than 1.7% (0.23% in base case scenario), no follow-up is the optimal strategy. If annual risk of rupture is more than 1.7%, coiling should be performed directly.

Conclusions and Relevance

Given the current literature, no preventive treatment or imaging follow-up is the most effective strategy in patients with aneurysms that are 3 mm or smaller, resulting in better health outcomes. More aggressive imaging surveillance for aneurysm growth or preventive treatment should be reserved for patients with a high risk of rupture. Given these findings, it is important to critically evaluate the appropriateness of current clinical practices, and potentially determine specific guidelines to reflect the most effective management strategy for patients with incidental, tiny UIAs.

MR Angiography Screening and Surveillance for Intracranial Aneurysms in Autosomal Dominant Polycystic Kidney Disease: A Cost-effectiveness Analysis

Background Autosomal dominant polycystic kidney disease (ADPKD) affects one in 400 to one in 1000 individuals; 10%-11% of these individuals have intracranial aneurysms. The frequency and patterns of screening for intracranial aneurysms have not been defined. Purpose To evaluate different MR angiography screening and surveillance strategies for unruptured intracranial aneurysms in patients with ADPKD. Materials and Methods A Markov decision-analytic model was constructed accounting for both costs and outcomes from a societal perspective. Five different management strategies were evaluated: (a) no screening for intracranial aneurysm, (b) one-time screening with annual MR angiography follow-up in patients with intracranial aneurysm, (c) MR angiographic screening every 5 years with endovascular treatment in detected intracranial aneurysm, (d) MR angiography screening every 5 years with annual MR angiography follow-up in patients with intracranial aneurysm, and (e) MR angiography screening every 5 years with biennial follow-up in patients with intracranial aneurysm. One-way, two-way, and probabilistic sensitivity analyses were performed. Results Base case calculation shows that MR angiography screening of patients with ADPKD every 5 years and annual follow-up in patients with detected intracranial aneurysm is the optimal strategy (cost, $19 839; utility, 25.86 quality-adjusted life years), which becomes more favorable as the life expectancy increases beyond 6 years. The conclusion remains robust in probabilistic and one-way sensitivity analyses. When the prevalence of intracranial aneurysms is greater than 10%, annual rupture risk is 0.35%-2.5%, and the rate of de novo aneurysm detection is lower than 1.8%, MR angiography screening every 5 years with annual MR angiography follow-up is the favorable strategy. Conclusion Screening for intracranial aneurysms with MR angiography in patients with autosomal dominant polycystic kidney disease is cost-effective. Repeat screening every 5 years should be performed after a negative initial study. Annual surveillance MR angiography is optimal in patients with detected, incidental intracranial aneurysm, and treatment may be considered in patients with growing, high-risk aneurysms. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Anzai in this issue.

Risk of Radiation-Induced Cancer From Computed Tomography Angiography Use in Imaging Surveillance for Unruptured Cerebral Aneurysms

Background and Purpose- Although computed tomography angiography (CTA) is an excellent, noninvasive imaging modality for surveillance of intracranial aneurysms, radiation concerns have been cited to restrict its use in surveillance imaging. The goal of this study was to estimate distributions of radiation-induced central nervous system cancer incidence from CTA surveillance for intracranial aneurysms, and the impact of frequency and duration of surveillance imaging using follow-up CTAs. Methods- Simulation-modeling approach was performed using data on CTA associated radiation risk. We used the Radiation Risk Assessment Tool, based on the data using the BEIR VII report (BEIR VII). Each CTA was assigned as a separate exposure event. Men and women, respectively, starting surveillance imaging at 30, 40, and 50 years and receiving annual CTAs were considered as separate subgroups. As a comparison, we also calculated the radiation-induced cancer risk in the same groups of patients but receiving CTAs every 2 and 5 years, respectively. Results- CTA-associated excess cancer risk per exposure increases relatively more rapidly with the first 10 exposures and plateaus after the 44th exposure. On average, per CTA incurs ≈0.0026% in excess lifetime cancer risk. Receiving CTA follow-up at a younger age, more frequent follow-up, longer surveillance period, and men are the major factors contributing to an elevated excess lifetime risk. In the highest risk group, male patient receiving annual CTA follow-ups from the age of 30 years, the excess lifetime risk is 0.115% at the age of 81 years. Conclusions- Radiation-induced brain cancer incidence associated with unruptured intracranial aneurysm surveillance strategies using CTA is low relative to the risk for aneurysmal rupture. Further cost-effectiveness/utility analyses might help assess this risk in the context of aneurysmal ruptures prevented by surveillance imaging.

Noninvasive Neuromonitoring: Current Utility in Subarachnoid Hemorrhage, Traumatic Brain Injury, and Stroke

Noninvasive neuromonitoring is increasingly being used to monitor the course of primary brain injury and limit secondary brain damage of patients in the neurocritical care unit. Proposed advantages over invasive neuromonitoring methods include a lower risk of infection and bleeding, no need for surgical installation, mobility and portability of some devices, and safety. The question, however, is whether noninvasive neuromonitoring is practical and trustworthy enough already. We searched the recent literature and reviewed English-language studies on noninvasive neuromonitoring in subarachnoid hemorrhage, traumatic brain injury, and ischemic and hemorrhagic stroke between the years 2010 and 2015. We found 88 studies that were eligible for review including the methods transcranial ultrasound, electroencephalography, evoked potentials, near-infrared spectroscopy, bispectral index, and pupillometry. Noninvasive neuromonitoring cannot yet completely replace invasive methods in most situations, but has great potential being complementarily integrated into multimodality monitoring, for guiding management, and for limiting the use of invasive devices and in-hospital transports for imaging.

Management of Small Unruptured Intracranial Aneurysms: A Survey of Neuroradiologists

BACKGROUND AND PURPOSE

The long-term history and management of unruptured intracranial aneurysms is not well understood. Our aim was to determine current practice patterns in the management of unruptured intracranial aneurysms, especially regarding imaging surveillance for conservatively managed aneurysms of this type.

MATERIALS AND METHODS

An on-line survey was designed to examine physician practice and preference regarding the management of small unruptured intracranial aneurysms (≤7 mm in diameter). The survey was circulated to members of the American Society of Neuroradiology. Participation was voluntary, and all responses were anonymous.

RESULTS

A total of 227 individual survey responses were obtained and included in the analysis with 54.6% (124/227) from diagnostic neuroradiologists (practicing >50% neuroradiology) and one-third (29%) from neurointerventional radiologists. One hundred seventy-three of 227 responded that routine, periodic imaging surveillance would be appropriate for conservatively managed unruptured intracranial aneurysms, and 84% of respondents recommended surveillance frequency of at least once a year. Fifty-nine percent favored indefinite, life-long follow-up for small unruptured intracranial aneurysms, and a similar number of respondents favored noncontrast MR angiography for aneurysm follow-up. Significant heterogeneity was found in size measurements used to assess aneurysms and criteria used to define growth on surveillance imaging.

CONCLUSIONS

The natural history of intracranial aneurysms is not well-understood. A large proportion of incidentally detected, unruptured aneurysms are small (<7 mm). The survey results show significant heterogeneity in practice even among neuroradiologists and underlies the need to standardize imaging practice. Further studies are needed to assess the optimal frequency and duration of surveillance imaging for unruptured intracranial aneurysms. The criteria used to measure aneurysms and define growth on imaging also need to be standardized.

Predicting delayed cerebral ischemia after subarachnoid hemorrhage using physiological time series data

To develop and validate a prediction model for delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) using a temporal unsupervised feature engineering approach, demonstrating improved precision over standard features. 488 consecutive SAH admissions from 2006 to 2014 to a tertiary care hospital were included. Models were trained on 80%, while 20% were set aside for validation testing. Baseline information and standard grading scales were evaluated: age, sex, Hunt Hess grade, modified Fisher Scale (mFS), and Glasgow Coma Scale (GCS). An unsupervised approach applying random kernels was used to extract features from physiological time series (systolic and diastolic blood pressure, heart rate, respiratory rate, and oxygen saturation). Classifiers (Partial Least Squares, linear and kernel Support Vector Machines) were trained on feature subsets of the derivation dataset. Models were applied to the validation dataset. The performances of the best classifiers on the validation dataset are reported by feature subset. Standard grading scale (mFS): AUC 0.58. Combined demographics and grading scales: AUC 0.60. Random kernel derived physiologic features: AUC 0.74. Combined baseline and physiologic features with redundant feature reduction: AUC 0.77. Current DCI prediction tools rely on admission imaging and are advantageously simple to employ. However, using an agnostic and computationally inexpensive learning approach for high-frequency physiologic time series data, we demonstrated that our models achieve higher classification accuracy.

Incorporating High-Frequency Physiologic Data Using Computational Dictionary Learning Improves Prediction of Delayed Cerebral Ischemia Compared to Existing Methods

Purpose

Accurate prediction of delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) can be critical for planning interventions to prevent poor neurological outcome. This paper presents a model using convolution dictionary learning to extract features from physiological data available from bedside monitors. We develop and validate a prediction model for DCI after SAH, demonstrating improved precision over standard methods alone.

Methods

488 consecutive SAH admissions from 2006 to 2014 to a tertiary care hospital were included. Models were trained on 80%, while 20% were set aside for validation testing. Modified Fisher Scale was considered the standard grading scale in clinical use; baseline features also analyzed included age, sex, Hunt-Hess, and Glasgow Coma Scales. An unsupervised approach using convolution dictionary learning was used to extract features from physiological time series (systolic blood pressure and diastolic blood pressure, heart rate, respiratory rate, and oxygen saturation). Classifiers (partial least squares and linear and kernel support vector machines) were trained on feature subsets of the derivation dataset. Models were applied to the validation dataset.

Results

The performances of the best classifiers on the validation dataset are reported by feature subset. Standard grading scale (mFS): AUC 0.54. Combined demographics and grading scales (baseline features): AUC 0.63. Kernel derived physiologic features: AUC 0.66. Combined baseline and physiologic features with redundant feature reduction: AUC 0.71 on derivation dataset and 0.78 on validation dataset.

Conclusion

Current DCI prediction tools rely on admission imaging and are advantageously simple to employ. However, using an agnostic and computationally inexpensive learning approach for high-frequency physiologic time series data, we demonstrated that we could incorporate individual physiologic data to achieve higher classification accuracy.

Heart Rate Variability for the Early Detection of Delayed Cerebral Ischemia

Delayed cerebral ischemia is considered the leading cause of death or major disability in subarachnoid hemorrhage after the impact of the initial event and rebleeding. Waiting to treat patients until they exhibit clinical symptoms of ischemia is too late to prevent cerebral infarction for more than 60% of patients, and transcranial Doppler ultrasonography has not proven to be a reliable screening tool to identify high-risk patients. Continuous heart rate variability monitoring may provide an alternative screening strategy to identify patients at high risk for delayed cerebral ischemia. Heart rate variability is a composite reflection of autonomic outflow, neuroendocrine influences, and autonomic responsiveness. Most importantly, heart rate variability is responsive to changes in systemic inflammation, which evidence suggests is important to the causal pathway of delayed cerebral ischemia. The clinical application of continuous heart rate variability monitoring in critical care is relatively recent despite its existence for more than 50 years. Initial studies suggest promise for heart rate variability monitoring as a delayed cerebral ischemia screening tool, but significant research is still required before this approach may achieve clinical applicability and bring benefit to patients.

Growth of Untreated Unruptured Small-sized Aneurysms (≺7mm): Incidence and Related Factors

PURPOSE

The need to treat small (<7 mm) unruptured aneurysms is still controversial, despite data collected through several large cohort studies. Such lesions typically are incidental findings, usually followed for potential growth through serial imaging. For this study, growth estimates for untreated unruptured small-sized aneurysms were generated, examining incidence and related risk factors.

METHODS

A cohort of 135 consecutive patients harboring 173 untreated unruptured small-sized aneurysms (<7 mm) was subjected to extended monitoring (mean, 73.1 ± 30.0 months). Growth was defined as a 1-mm increase at minimum in one or more aneurysmal dimensions or as a significant change in shape. Medical records and radiological data were reviewed. Cumulative growth rate and related risk factors were analyzed via Cox proportional hazards regression and Kaplan-Meier product-limit estimator.

RESULTS

A total of 28 aneurysms (16.2%) displayed growth during continued surveillance (1054.1 aneurysm-years). The annual growth rate was 2.65% per aneurysm-year, with 15 surfacing within 60 months and 13 after 60 months. Multivariate analysis indicated that bifurcation type was the sole significant risk factor (hazard ratio HR = 7.64; p < 0.001) in terms of growth. Cumulative survival rates without growth were significantly lower in subjects with bifurcation aneurysms than with side-wall aneurysms (p < 0.001). During the follow-up period, one patient suffered a subarachnoid hemorrhage and then aneurysm growth was detected.

CONCLUSION

Most (83.8%) untreated unruptured small-sized aneurysms (<7 mm) remained stable and devoid of growth in long-term follow-up. Because bifurcation aneurysms were prone to eventual growth, careful long-term monitoring at regular intervals is advised if left untreated.

RNF213 Is Associated with Intracranial Aneurysms in the French-Canadian Population

Intracranial aneurysms (IAs) are the result of focal weakness in the artery wall and have a complex genetic makeup. To date, genome-wide association and sequencing studies have had limited success in identifying IA risk factors. Distinct populations, such as the French-Canadian (FC) population, have increased IA prevalence. In our study, we used exome sequencing to prioritize risk variants in a discovery cohort of six FC families affected by IA, and the analysis revealed an increased variation burden for ring finger protein 213 (RNF213). We resequenced RNF213 in a larger FC validation cohort, and association tests on further identified variants supported our findings (SKAT-O, p = 0.006). RNF213 belongs to the AAA+ protein family, and two variants (p.Arg2438Cys and p.Ala2826Thr) unique to affected FC individuals were found to have increased ATPase activity, which could lead to increased risk of IA by elevating angiogenic activities. Common SNPs in RNF213 were also extracted from the NeuroX SNP-chip genotype data, comprising 257 FC IA-affected and 1,988 control individuals. We discovered that the non-ancestral allele of rs6565666 was significantly associated with the affected individuals (p = 0.03), and it appeared as though the frequency of the risk allele had changed through genetic drift. Although RNF213 is a risk factor for moyamoya disease in East Asians, we demonstrated that it might also be a risk factor for IA in the FC population. It therefore appears that the function of RNF213 can be differently altered to predispose distinct populations to dissimilar neurovascular conditions, highlighting the importance of a population's background in genetic studies of heterogeneous disease.

Prediction of Delayed Cerebral Ischemia After Subarachnoid Hemorrhage Using Cerebral Blood Flow Velocities and Cerebral Autoregulation Assessment

BACKGROUND

The risk of delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) is associated with large cerebral artery vasospasm, but vasospasm is not a strong predictor for DCI. Assessment of cerebral autoregulation with transcranial Doppler (TCD) may improve the prediction of DCI. The aim of this prospective study was to assess the value of TCD-derived variables to be used alone or in combination for prediction of DCI.

METHODS

We included consecutive patients with low-grade aneurysmal SAH within 4 days of aneurysm rupture. Cerebral autoregulation was evaluated using the moving correlation coefficient Mx calculated from spontaneous fluctuations of cerebral blood flow velocities and arterial blood pressure. Transcranial color-coded sonography was performed to assess large artery vasospasm.

RESULTS

Thirty patients (19 women and 11 men; mean age ± SD 44.7 ± 12.1 years) were included. Twenty (66.7%) patients had vasospasm. DCI occurred in six (20%) patients after a median delay of 10 days (range 8-13 days). Cerebral autoregulation was impaired at baseline and at day 7 and then returned to normal at day 14. Neither cerebral autoregulation impairment nor large artery vasospasm alone was associated with DCI. In contrast, the combination of large artery vasospasm with worsening impairment of cerebral autoregulation from baseline to day 7 was significantly correlated to subsequent DCI (p = 0.007).

CONCLUSIONS

Early deterioration of cerebral autoregulation was strongly predictive of DCI in patients with large artery vasospasm after low-grade SAH. Our results suggest that consideration to both cerebral blood flow velocities and cerebral autoregulation may improve the prediction of DCI.

Treatment outcomes of unruptured intracranial aneurysm; experience of 1,231 consecutive aneurysms

BACKGROUND

The aim of this study was to review our experience with surgical clipping and endovascular treatment (EVT) of unruptured intracranial aneurysms (UIAs), with a special focus on complications.

METHODS

We retrospectively analyzed clinical and radiological data from patients who underwent surgery or EVT. Surgery was performed by one neurosurgeon, and EVT was performed by two neurointerventionists according to one hybrid neurosurgeon's decision. Adverse events included the following: (1) decline of the modified Rankin Scale (mRS) score from 1 to 2 and (2) any unexpected neurological deficit or imaging finding affecting the prognosis and/or requiring additional procedures, medication, or prolonged hospital stay.

RESULTS

Of the 1231 UIAs in 1124 patients, 625 (50.7 %) aneurysms were treated with surgery, and 606 (49.3 %) aneurysms were treated with EVT. The overall complication rate of UIA treatment was 3.2 %. The rate of adverse events was 2.4 %, and the rates of morbidity and mortality were 0.6 and 0.2 %, respectively. The rates of adverse events, morbidity, and mortality were not significantly different between surgery and EVT. The rate of hospital use for EVT was stationary over the years of the study. Posterior circulation in surgery, large aneurysms (>15 mm) in EVT, and stent- or balloon-assisted procedures in EVT were associated with the occurrence of complications. Poor clinical outcome (mRS of 3-6) was 0.8 % at hospital discharge.

CONCLUSIONS

Both UIA treatment modalities decided by one hybrid neurosurgeon showed low complication rates and good clinical outcomes in this study. These results may serve as a point of reference for clinical decision-making for patients with UIA.

Guidelines for the Management of Patients With Unruptured Intracranial Aneurysms: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

PURPOSE

The aim of this updated statement is to provide comprehensive and evidence-based recommendations for management of patients with unruptured intracranial aneurysms.

METHODS

Writing group members used systematic literature reviews from January 1977 up to June 2014. They also reviewed contemporary published evidence-based guidelines, personal files, and published expert opinion to summarize existing evidence, indicate gaps in current knowledge, and when appropriate, formulated recommendations using standard American Heart Association criteria. The guideline underwent extensive peer review, including review by the Stroke Council Leadership and Stroke Scientific Statement Oversight Committees, before consideration and approval by the American Heart Association Science Advisory and Coordinating Committee.

RESULTS

Evidence-based guidelines are presented for the care of patients presenting with unruptured intracranial aneurysms. The guidelines address presentation, natural history, epidemiology, risk factors, screening, diagnosis, imaging and outcomes from surgical and endovascular treatment.

Heart rate variability for preclinical detection of secondary complications after subarachnoid hemorrhage

BACKGROUND

We sought to determine if monitoring heart rate variability (HRV) would enable preclinical detection of secondary complications after subarachnoid hemorrhage (SAH).

METHODS

We studied 236 SAH patients admitted within the first 48 h of bleed onset, discharged after SAH day 5, and had continuous electrocardiogram records available. The diagnosis and date of onset of infections and DCI events were prospectively adjudicated and documented by the clinical team. Continuous ECG was collected at 240 Hz using a high-resolution data acquisition system. The Tompkins-Hamilton algorithm was used to identify R-R intervals excluding ectopic and abnormal beats. Time, frequency, and regularity domain calculations of HRV were generated over the first 48 h of ICU admission and 24 h prior to the onset of each patient's first complication, or SAH day 6 for control patients. Clinical prediction rules to identify infection and DCI events were developed using bootstrap aggregation and cost-sensitive meta-classifiers.

RESULTS

The combined infection and DCI model predicted events 24 h prior to clinical onset with high sensitivity (87 %) and moderate specificity (66 %), and was more sensitive than models that predicted either infection or DCI. Models including clinical and HRV variables together substantially improved diagnostic accuracy (AUC 0.83) compared to models with only HRV variables (AUC 0.61).

CONCLUSIONS

Changes in HRV after SAH reflect both delayed ischemic and infectious complications. Incorporation of concurrent disease severity measures substantially improves prediction compared to using HRV alone. Further research is needed to refine and prospectively evaluate real-time bedside HRV monitoring after SAH.

Withdrawal of technological life support following subarachnoid hemorrhage

BACKGROUND

Prognostication of mortality or severe disability often prompts withdrawal of technological life support in patients following aneurysmal subarachnoid hemorrhage (aSAH). We assessed admission factors impacting decisions to withdraw treatment after aSAH.

METHODS

Prospectively collected data of aSAH patients admitted to our institution between 1991 and 2009 were reviewed. Patients given comfort care measures were identified, including early withdrawal of treatment (<72 h after admission). Independent predictors of treatment withdrawal were assessed with multivariable analysis.

RESULTS

The study included 1,134 patients, of whom 72 % were female, 58 % white, and 38 % black or African-American. Mean age was 52.5 ± 14.0 years. In-hospital mortality was 18.3 %. Of the 207 patients who died, treatment was withdrawn in 72 (35 %) and comfort measures instituted early in 31 (15 %). Among patients who died, WOLST was associated with older age (63.6 ± 14.2 years, WOLST vs. 55.6 ± 13.7 years, no WOLST, p < 0.001); GCS score <8 (62 % of WOLST vs. 44 % with no WOLST, p = 0.010); HH >3 (72 % of WOLST vs. 53 % with no WOLST, p = 0.008); and hydrocephalus (81 % of WOLST vs. 63 % with no WOLST, p = 0.009). Independent predictors of WOLST were poorer Hunt and Hess grade (AOR 1.520, 95 % CI 1.160-1.992, p = 0.002) and older age (AOR 1.045, 95 % CI 1.022-1.068, p < 0.001) with the latter also impacting early WOLST decisions.

CONCLUSIONS

Older age and poor clinical grade on presentation predicted WOLST, and age predicted decisions to withdraw treatment earlier following aSAH. While based on prognosis, and in some cases patient wishes, this may also constitute a self-fulfilling prophecy in others.

Genealogy of Training in Vascular Neurosurgery

Remarkable advances and changes in the landscape of neurovascular disease have occurred recently. Concurrently, a paradigm shift in training and resident education is underway. This crossroad of unique opportunities and pressures necessitates creative change in the training of future vascular neurosurgeons to allow incorporation of surgical advances, new technology, and supplementary treatment modalities in a setting of reduced work hours and increased public scrutiny. This article discusses the changing landscape in neurovascular disease treatment, followed by the recent changes in resident training, and concludes with our view of the future of training in vascular neurosurgery.

Factors affecting formation and rupture of intracranial saccular aneurysms

Unruptured intracranial aneurysms represent a decisional challenge. Treatment risks have to be balanced against an unknown probability of rupture. A better understanding of the physiopathology is the basis for a better prediction of the natural history of an individual patient. Knowledge about the possible determining factors arises from a careful comparison between ruptured versus unruptured aneurysms and from the prospective observation and analysis of unbiased series with untreated, unruptured aneurysms. The key point is the correct identification of the determining variables for the fate of a specific aneurysm in a given individual. Thus, the increased knowledge of mechanisms of formation and eventual rupture of aneurysms should provide significant clues to the identification of rupture-prone aneurysms. Factors like structural vessel wall defects, local hemodynamic stress determined also by peculiar geometric configurations, and inflammation as trigger of a wall remodeling are crucial. In this sense the study of genetic modifiers of inflammatory responses together with the computational study of the vessel tree might contribute to identify aneurysms prone to rupture. The aim of this article is to underline the value of a unifying hypothesis that merges the role of geometry, with that of hemodynamics and of genetics as concerns vessel wall structure and inflammatory pathways.

Nontraumatic subarachnoid hemorrhage in maintenance dialysis hospitalizations: trends and outcomes

BACKGROUND AND PURPOSE

Subarachnoid hemorrhage (SAH) is associated with high mortality, and patients on maintenance dialysis have been shown to be at higher risk for stroke including SAH. However, the outcomes of patients on maintenance dialysis with SAH are not well known. This study was designed to look at incidence and outcomes of SAH in those on maintenance dialysis.

METHODS

Using the Nationwide Inpatient Sample Database, hospitalizations with nontraumatic SAH were identified. Age-adjusted incidence rates were calculated by direct standardization to the 2000 US standard population. Logistic regression was used to assess the risk factors for mortality.

RESULTS

Of an estimated 149,091 hospitalizations with SAH, 1631 patients (10.9%) were on maintenance dialysis. Unadjusted incidence of SAH hospitalizations was higher in maintenance dialysis than in the general population (73.5 versus 11.2 per 100,000 population), and similar results were seen on age-adjusted analysis. The unadjusted all-cause inpatient mortality rate for SAH admissions was higher in maintenance dialysis versus the general population (38.4% versus 21.9%; P<0.001). Maintenance dialysis was an independent predictor of mortality (odds ratio, 2.48; 95% confidence interval, 1.85-3.34), although other significant predictors of mortality were similar in both subgroups. Incidence of SAH hospitalizations has been relatively stable during the study period, but mortality seems to be decreasing.

CONCLUSIONS

SAH hospitalizations are more common and associated with higher mortality in patients on maintenance dialysis than in the general population. Although being on maintenance dialysis is an independent predictor for mortality in patients with SAH, other predictors of mortality evaluated in this study are not necessarily different between the 2 groups.

Endovascular methods for the treatment of intracranial cerebral aneurysms

This article briefly discusses the clinical features, natural history, and epidemiology of intracranial cerebral aneurysms, along with current diagnostic imaging techniques for their detection. The main focus is on the basic techniques used in endovascular coiling of ruptured and nonruptured saccular intracranial cerebral aneurysms. After a discussion of each technique, a short review of the results of each form of treatment is given, concentrating on reported large case series. Specific complications related to the endovascular treatment of saccular intracranial aneurysms are then discussed.

Long-term excess mortality of patients with treated and untreated unruptured intracranial aneurysms

BACKGROUND AND AIM

Subarachnoid haemorrhage (SAH) patients have an excess mortality proportion in long-term outcome studies because of the high rate of cerebrovascular and cardiovascular deaths. The aim of the present study was to assess the excess long-term mortality among patients with unruptured aneurysms with no previous SAH and to compare excess mortality after coiling, clipping and without treatment.

METHODS

Between 1989 and 1999, a total of 1294 patients with intracranial aneurysms were admitted to our hospital. Of these, 1154 had previous SAH and were excluded leaving 140 patients with 178 intracranial unruptured aneurysms as the study population. The patients were followed up until death or by the end of April 2011. Causes of death were determined. Relative survival ratios (RSRs) were calculated and compared with the matched general population.

RESULTS

Mean follow-up time was 13 years (range 1-19). During the follow-up period, 36% of patients died. Death was caused by cerebrovascular event in half of the cases. There were 12% excess mortality at 15 years in men and 35% excess mortality in women compared with general population. Excess mortality among women over 50 years was significantly higher than that among men (p=0.018).

CONCLUSIONS

Patients with untreated unruptured aneurysms have 50% excess long-term mortality compared with general population. Men with treated unruptured aneurysms have a survival proportion comparable with matched general population. Women, instead, have 28% excess mortality after surgical treatment and 23% excess mortality after endovascular treatment of unruptured aneurysms.

Antiepileptic drugs for the primary and secondary prevention of seizures after subarachnoid haemorrhage

BACKGROUND

Subarachnoid haemorrhage may result in seizures both acutely and in the longer term. The use of antiepileptic drugs (AEDs) in the primary and secondary prevention of seizures after subarachnoid haemorrhage is uncertain, and there is currently no consensus on treatment.

OBJECTIVES

To assess the effects of AEDs for the primary and secondary prevention of seizures after subarachnoid haemorrhage.

SEARCH METHODS

We searched the Cochrane Epilepsy Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 1) in The Cochrane Library, and MEDLINE (1946 to 12th March 2013). We checked the reference lists of articles retrieved from these searches.

SELECTION CRITERIA

We considered all randomised and quasi-randomised controlled trials in which patients were assigned to a treatment (one or more AEDs) or placebo.

DATA COLLECTION AND ANALYSIS

Two review authors (RM and JK) independently screened and assessed the methodological quality of the studies. If studies were included, one author extracted the data and the other checked it.

MAIN RESULTS

No relevant studies were found.

AUTHORS' CONCLUSIONS

There was no evidence to support or refute the use of antiepileptic drugs for the primary or secondary prevention of seizures related to subarachnoid haemorrhage. Well-designed randomised controlled trials are urgently needed to guide clinical practice.

Changes in hospital mortality for United States intensive care unit admissions from 1988 to 2012

Introduction

A decrease in disease-specific mortality over the last twenty years has been reported for patients admitted to United States (US) hospitals, but data for intensive care patients are lacking. The aim of this study was to describe changes in hospital mortality and case-mix using clinical data for patients admitted to multiple US ICUs over the last 24 years.

Methods

We carried out a retrospective time series analysis of hospital mortality using clinical data collected from 1988 to 2012. We also examined the impact of ICU admission diagnosis and other clinical characteristics on mortality over time. The potential impact of hospital discharge destination on mortality was also assessed using data from 2001 to 2012.

Results

For 482,601 ICU admissions there was a 35% relative decrease in mortality from 1988 to 2012 despite an increase in age and severity of illness. This decrease varied greatly by diagnosis. Mortality fell by >60% for patients with chronic obstructive pulmonary disease, seizures and surgery for aortic dissection and subarachnoid hemorrhage. Mortality fell by 51% to 59% for six diagnoses, 41% to 50% for seven diagnoses, and 10% to 40% for seven diagnoses. The decrease in mortality from 2001 to 2012 was accompanied by an increase in discharge to post-acute care facilities and a decrease in discharge to home.

Conclusions

Hospital mortality for patients admitted to US ICUs has decreased significantly over the past two decades despite an increase in the severity of illness. Decreases in mortality were diagnosis specific and appear attributable to improvements in the quality of care, but changes in discharge destination and other confounders may also be responsible.

Clinical management guidelines for subarachnoid haemorrhage. Diagnosis and treatment

OBJECTIVE

To update the Spanish Society of Neurology's guidelines for subarachnoid haemorrhage diagnosis and treatment.

MATERIAL AND METHODS

A review and analysis of the existing literature. Recommendations are given based on the level of evidence for each study reviewed.

RESULTS

The most common cause of spontaneous subarachnoid haemorrhage (SAH) is cerebral aneurysm rupture. Its estimated incidence in Spain is 9/100 000 inhabitants/year with a relative frequency of approximately 5% of all strokes. Hypertension and smoking are the main risk factors. Stroke patients require treatment in a specialised centre. Admission to a stroke unit should be considered for SAH patients whose initial clinical condition is good (Grades I or II on the Hunt and Hess scale). We recommend early exclusion of aneurysms from the circulation. The diagnostic study of choice for SAH is brain CT (computed tomography) without contrast. If the test is negative and SAH is still suspected, a lumbar puncture should then be performed. The diagnostic tests recommended in order to determine the source of the haemorrhage are MRI (magnetic resonance imaging) and angiography. Doppler ultrasonography studies are very useful for diagnosing and monitoring vasospasm. Nimodipine is recommended for preventing delayed cerebral ischaemia. Blood pressure treatment and neurovascular intervention may be considered in treating refractory vasospasm.

CONCLUSIONS

SAH is a severe and complex disease which must be managed in specialised centres by professionals with ample experience in relevant diagnostic and therapeutic processes.

Treatment strategies for complex intracranial aneurysms: review of a 12-year experience at the university of cincinnati

Complex intracranial aneurysms (CIAs) include those classified as giant, those located in brain regions of technically difficult access, or that involve arterial trunks/branches, and/or have complicated wall structure. We reviewed retrospectively our management of such lesions in a 12-year period. From 1997 to 2009, 192 patients were admitted with CIAs (133 females, 59 males; average age 55 years); 128 presented with subarachnoid hemorrhage (SAH) and 64 with unruptured, symptomatic CIAs. The SAH group had 73 anterior- and 55 posterior-circulation aneurysms. Most frequent location was middle cerebral artery. Treatment strategies included clipping (65.6%), coiling/stenting (28.1%), bypass (3.1%), no treatment (3.1%). Coiling/stenting was exclusively used for posterior-circulation aneurysms. Outcomes were good (modified Rankin Scale [mRS] 0 to 2) in 54 patients (42.2%), fair (mRS = 3 to 4) in 38 (29.7%), and poor (mRS = 5 to 6) in 36 (28.1%). Among unruptured CIAs, there were 47 anterior- and 17 posterior-circulation aneurysms. Most frequent location was ophthalmic. Thirty (46.9%) were clipped, 19 (29.7%) coiled, 6 (9.4%) by-passed, 2 (3.1%) wrapped, and 7 (10.9%) had no treatment. Outcomes were good in 57 patients (89%) and fair in 7 (11%). Good outcomes were obtained in unruptured CIAs using a multidisciplinary approach. Ruptured CIAs carry a significantly worse prognosis than overall SAH patients.

Three-dimensional rotational angiography for craniotomy planning and postintervention evaluation of intracranial aneurysms

PURPOSE

The authors evaluated the usefulness of three-dimensional rotational angiography (3DRA) in surgical planning and postoperative evaluation of cerebral aneurysms.

MATERIALS AND METHODS

A total of 111 consecutive aneurysms in 100 patients (32 emergency referrals due to haemorrhage) were evaluated with 3DRA over a period of 3 years. The rotational study was always performed with a single injection of 20 cc of contrast agent in the afferent vessel after diagnostic cerebral angiography in the two orthogonal projections. Three-dimensional reconstructions were obtained for the pre- and postoperative assessment.

RESULTS

Three-dimensional RA provides a virtual view of the surgical field with the same orientation required for the surgical approach and, compared with surgical findings, reliably defined location, orientation, morphology and relationship with parent vessels of the aneurysm in all cases. Postoperatively, it allowed better assessment of any residual lesion and of the relationship between surgical clips and parent vessels, compared with standard 2D angiography.

CONCLUSIONS

3DRA is a reliable method for preliminary assessment of cerebral aneurysms undergoing surgery. It provides multiple projections with a preview of the surgical field and study of lesion characteristics, which can help achieve faster and safer surgery. Compared with 2D angiography, the 3D model, with its multiple views, allows better assessment of postoperative outcomes. The method also significantly reduces the number of angiographic projections and therefore radiation and contrast-medium dose to the patient.

Intracranial aneurysms: review of current treatment options and outcomes

Intracranial aneurysms are present in roughly 5% of the population, yet most are often asymptomatic and never detected. Development of an aneurysm typically occurs during adulthood, while formation and growth are associated with risk factors such as age, hypertension, pre-existing familial conditions, and smoking. Subarachnoid hemorrhage, the most common presentation due to aneurysm rupture, represents a serious medical condition often leading to severe neurological deficit or death. Recent technological advances in imaging modalities, along with increased understanding of natural history and prevalence of aneurysms, have increased detection of asymptomatic unruptured intracranial aneurysms (UIA). Studies reporting on the risk of rupture and outcomes have provided much insight, but the debate remains of how and when unruptured aneurysms should be managed. Treatment methods include two major intervention options: clipping of the aneurysm and endovascular methods such as coiling, stent-assisted coiling, and flow diversion stents. The studies reviewed here support the generalized notion that endovascular treatment of UIA provides a safe and effective alternative to surgical treatment. The risks associated with endovascular repair are lower and incur shorter hospital stays for appropriately selected patients. The endovascular treatment option should be considered based on factors such as aneurysm size, location, patient medical history, and operator experience.

Trends in incidence and in short term survival following a subarachnoid haemorrhage in Scotland, 1986-2005: a retrospective cohort study

Background

To examine age and sex specific incidence and 30 day case fatality for subarachnoid haemorrhage (SAH) in Scotland over a 20 year period.

Methods

A retrospective cohort study using routine hospital discharge data linked to death records.

Results

Between 1986 and 2005, 12,056 individuals experienced an incident SAH. Of these 10,113 (84%) survived to reach hospital. Overall age-standardised incidence rates were greater in women than men and remained relatively stable over the study period. In 2005, incidence in women was 12.8 (95% CI 11.5 to 14.2) and in men 7.9 (95% CI 6.9 to 9.1). 30 day case fatality in individuals hospitalised with SAH declined substantially, falling from 30.0% in men and 33.9% in women in 1986-1990 to 24.5% in men and 29.1% in women in 2001-2005. For both men and women, the largest reductions were observed in those aged between 40 to 59 years. After adjustment for age, socio-economic status and co-morbidity, the odds of death at 30 days in 2005 compared to odds of death in 1986 was 0.64 (0.54 to 0.76), p < 0.001 for those below 70 years, and 1.14 (0.83 to 1.56), p = 0.4 in those 70 years and above.

Conclusions

Incidence rates for SAH remained stable between 1986 and 2005 suggesting that a better understanding of SAH risk factors and their reduction is needed. 30 day case fatality rates have declined substantially, particularly in middle-age. However, they remain high and it is important to ensure that this is not due to under-diagnosis or under-treatment.

Impact of International Subarachnoid Aneurysm Trial results on treatment of ruptured intracranial aneurysms in the United States

Object

The utilization of endovascular treatment for ruptured intracranial aneurysms is expected to change since the publication of the International Subarachnoid Aneurysm Trial (ISAT) in 2002. The authors performed this analysis to determine the impact of ISAT results on treatment selection for ruptured intracranial aneurysms and associated in-hospital outcomes using nationally representative data.

Methods

We determined the national estimates of treatments used for ruptured intracranial aneurysms and associated in-hospital outcomes, length of stay, mortality, and cost incurred using the Nationwide Inpatient Survey (NIS) data. The NIS is the largest all-payer inpatient care database in the US and contains data from 986 hospitals approximating a 20% stratified sample of US hospitals. All the variables pertaining to hospitalization were compared between 2000–2002 and 2004–2006, and in-hospital outcomes were analyzed using multivariate analysis.

Results

In the 3-year periods prior to and after the ISAT, there were 70,637 and 77,352 admissions for ruptured intracranial aneurysms, respectively. There was a significant increase in endovascular treatment after publication of the ISAT (trend test, p < 0.0001) The in-hospital mortality for ruptured intracranial aneurysm admissions decreased from 27% to 24% (odds ratio [OR] 0.89, 95% CI 0.83–0.96, p = 0.003) after the publication of the ISAT. The cost of hospitalization after adjusting for procedures practices was not significantly higher after the publication of the ISAT ($21,437 vs $22,817, p < 0.89), but cost of hospitalization was higher in the post-ISAT period for patients undergoing endovascular procedure.

Conclusions

The results of the ISAT have been associated with a prominent change in practice patterns related to the treatment of ruptured aneurysms. The cost of hospitalization has increased and the mortality has decreased, presumably due to a larger proportion of patients receiving any treatment and endovascular treatment.

Long-term MRI findings of patients with embolized cerebral aneurysms

BACKGROUND

Long-term follow-up studies after endovascular treatment for intracranial aneurysm are still rare and inconclusive. Parenchymal infarctions related to aneurysms have mostly been studied in patients with subarachnoidal hemorrhage (SAH) but infarction rates in patients with endovascularly treated unruptured aneurysms have been little studied.

PURPOSE

To determine the frequency of permanent parenchymal lesions as detected in magnetic resonance imaging (MRI) in patients treated with endovascular coiling and to assess aneurysm-related infarctions after the initial treatment period.

MATERIAL AND METHODS

A total of 64 patients (32 with primarily ruptured aneurysms) with 69 embolized aneurysms were examined neurologically and by MRI and magnetic resonance angiography (MRA) more than 9 years after the initial endovascular treatment.

RESULTS

A total of 14 out of 32 (44%) SAH patients and 11 (34%) patients with unruptured aneurysms had parenchymal lesions in MRI. Infarctions were detected in 10 (31%) SAH patients and the majority (9/10, 90%) of them were aneurysm-related. All aneurysm-related infarctions were detected at the acute hospitalization stage. A total of six (55%) out of 11 infarctions in patients with unruptured aneurysms were aneurysm-related and two of them appeared after the treatment period. Patients with infarction had poorer clinical outcome than patients with no ischemic lesions in MRI.

CONCLUSION

Nineteen percent of patients with unruptured and 41% with ruptured aneurysms had aneurysm-related parenchymal lesions in MRI. Most of these were detected during acute treatment period. Aneurysm-related infarctions after treatment period are uncommon.

Stroke incidence is decreasing in whites but not in blacks: a population-based estimate of temporal trends in stroke incidence from the Greater Cincinnati/Northern Kentucky Stroke Study

BACKGROUND AND PURPOSE

Although other studies (in largely white populations) have found that stroke incidence declined during the 1990s, we previously reported that stroke incidence in our population (18% of which was black) did not change during that decade and that incidence rates in blacks were significantly higher than in whites. We sought to update temporal trends in stroke incidence by adding new data obtained from our large, biracial population in 2005. The objective of this study was to examine temporal trends in stroke incidence and case-fatality within a large biracial population over time by comparing stroke incidence rates from 1993 to 1994, 1999, and 2005.

METHODS

Within the Greater Cincinnati/Northern Kentucky population of 1.3 million, all strokes among area residents were ascertained at all local hospitals during July 1993 to June 19/94 and calendar years 1999 and 2005. A sampling scheme was used to ascertain cases in the out-of-hospital setting. Only first-ever strokes were included in this analysis. Race-specific incidence rates, standardized to the 2000 US Census population, and case-fatality rates were calculated.

RESULTS

The number of physician-confirmed first-ever strokes in patients >or=20 years of age was 1942 in 1993 to 1994, 2041 in 1999, and 1921 in 2005. In all study periods, blacks had higher stroke incidence than whites, and case-fatality rates were similar between races. In contrast to previous study periods, we found a significant decrease in overall stroke incidence in 2005. When stratified by race and stroke subtype, this change was driven by a decrease in ischemic stroke incidence among whites, whereas ischemic stroke incidence in blacks was unchanged. Hemorrhagic stroke incidence was unchanged in both races.

CONCLUSIONS

For the first time, we report a significant decrease in stroke incidence within our population, which is consistent with other reports in the literature. This decrease was found only among whites, which suggests a worsening of the racial disparity in stroke incidence.

Hospital mortality and complications of electively clipped or coiled unruptured intracranial aneurysm

BACKGROUND AND PURPOSE

To determine the hospital mortality rates associated with elective surgical clipping and endovascular coiling of unruptured intracranial aneurysms.

METHODS

We identified a cohort of patients electively admitted to US hospitals with the diagnosis of unruptured intracranial aneurysm from the National Inpatient Sample database for the years 2000 through 2006. Patient demographics, hospital-associated complications, and in-hospital mortality were compared among the treatment groups. A multivariate logistic regression analysis was used to identify independent variables associated with hospital mortality. Cochrane-Armitage test was used to assess the trend of hospital use of these procedures.

RESULTS

After data cleansing, 3738 (34.3%) patients had aneurysm clipping and 3498 (32.1%) had endovascular coiling. The basic demographics including age, race, and comorbidity indices were similar between the groups. The length of hospital stay was longer in the clipped population (median 4 versus 1 day; P<0.0001), incurring a higher hospital charge in the coiled population (median $42 070 versus $38 166; P<0.0001). Hospital mortality was higher in the clipped population: 60 (1.6%) versus 20 (0.57%; adjusted odds ratio 3.63; 95% CI, 1.57, 8.42). Perioperative intracerebral hemorrhage and acute ischemic stroke were higher in the clipped population. The rate of hospital use of the endovascular coiling has increased over the years included in this study (<0.0001).

CONCLUSIONS

Elective coiling of unruptured intracranial aneurysms is associated with fewer deaths and perioperative complications compared with elective clipping. The trend of hospital use of the coiling procedures has increased during recent years.