✓ The purpose of this study was to determine the symptoms at presentation and the incidence of intracranial hemorrhage (ICrH) caused by intracranial vascular malformations (IVMs) in a defined population. The authors used the Mayo Clinic medical records linkage system to detect all cases of IVM among residents of Olmsted County, Minnesota, during the period 1965 through 1992. Forty-eight IVMs were detected over the 27-year period. Twenty-nine of the 48 patients were symptomatic at presentation. The most common presenting symptom was ICrH, which was present in 20 patients, 69% of all symptomatic cases. Sixty-five percent of arteriovenous malformations (AVMs) presented with ICrH. The most common subtype of ICrH was intracerebral hemorrhage, which was found in nine of 20 patients; the second most common subtype was subarachnoid hemorrhage. The peak occurrence of hemorrhage was during the fifth decade of life. The age- and gender-adjusted occurrence of a first ICrH from an IVM among residents of Olmsted County, Minnesota was 0.82 per 100,000 person years (95% confidence interval 0.46–1.19). There was no increase in the detection of IVM-related ICrH throughout the study period. The 30-day mortality rate following ICrH was 17.6% for patients with an AVM and 25% for all patients with IVMs. This study provides unique data on symptoms at presentation and the incidence of ICrH and hemorrhage subtypes from IVMs on a population basis.
Robert D. Brown Jr., David O. Wiebers, James C. Torner and W. Michael O'Fallon
Kelly B. Mahaney, Robert D. Brown Jr., Irene Meissner, David G. Piepgras, John Huston III, Jie Zhang and James C. Torner
The aim of this study was to determine age-related differences in short-term (1-year) outcomes in patients with unruptured intracranial aneurysms (UIAs).
Four thousand fifty-nine patients prospectively enrolled in the International Study of Unruptured Intracranial Aneurysms were categorized into 3 groups by age at enrollment: < 50, 50–65, and > 65 years old. Outcomes assessed at 1 year included aneurysm rupture rates, combined morbidity and mortality from aneurysm procedure or hemorrhage, and all-cause mortality. Periprocedural morbidity, in-hospital morbidity, and poor neurological outcome on discharge (Rankin scale score of 3 or greater) were assessed in surgically and endovascularly treated groups. Univariate and multivariate associations of each outcome with age were tested.
The risk of aneurysmal hemorrhage did not increase significantly with age. Procedural and in-hospital morbidity and mortality increased with age in patients treated with surgery, but remained relatively constant with increasing age with endovascular treatment. Poor neurological outcome from aneurysm- or procedure-related morbidity and mortality did not differ between management groups for patients 65 years old and younger, but was significantly higher in the surgical group for patients older than 65 years: 19.0% (95% confidence interval [CI] 13.9%–24.4%), compared with 8.0% (95% CI 2.3%–13.6%) in the endovascular group and 4.2% (95% CI 2.3%–6.2%) in the observation group. All-cause mortality increased steadily with increasing age, but differed between treatment groups only in patients < 50 years of age, with the surgical group showing a survival advantage at 1 year.
Surgical treatment of UIAs appears to be safe, prevents 1-year hemorrhage, and may confer a survival benefit in patients < 50 years of age. However, surgery poses a significant risk of morbidity and death in patients > 65 years of age. Risk of endovascular treatment does not appear to increase with age. Risks and benefits of treatment in older patients should be carefully considered, and if treatment is deemed necessary for patients older than 65 years, endovascular treatment may be the best option.
Yasunori Nagahama, Lauren Allan, Daichi Nakagawa, Mario Zanaty, Robert M. Starke, Nohra Chalouhi, Pascal Jabbour, Robert D. Brown Jr., Colin P. Derdeyn, Enrique C. Leira, Joseph Broderick, Marc Chimowitz, James C. Torner and David Hasan
Clinical vasospasm and delayed cerebral ischemia (DCI) are devastating complications of aneurysmal subarachnoid hemorrhage (aSAH). Several theories involving platelet activation have been postulated as potential explanations of the development of clinical vasospasm and DCI. However, the effects of dual antiplatelet therapy (DAPT; aspirin and clopidogrel) on clinical vasospasm and DCI have not been previously investigated. The objective of this study was to evaluate the effects of DAPT on clinical vasospasm and DCI in aSAH patients.
Analysis of patients treated for aSAH during the period from July 2009 to April 2014 was performed in a single-institution retrospective study. Patients were divided into 2 groups: patients who underwent stent-assisted coiling or placement of flow diverters requiring DAPT (DAPT group) and patients who underwent coiling only without DAPT (control group). The frequency of symptomatic clinical vasospasm and DCI and of hemorrhagic complications was compared between the 2 groups, utilizing univariate and multivariate logistic regression.
Of 312 aSAH patients considered for this study, 161 met the criteria for inclusion and were included in the analysis (85 patients in the DAPT group and 76 patients in the control group). The risks of clinical vasospasm (OR 0.244, CI 95% 0.097–0.615, p = 0.003) and DCI (OR 0.056, CI 95% 0.01–0.318, p = 0.001) were significantly lower in patients receiving DAPT. The rates of hemorrhagic complications associated with placement of external ventricular drains and ventriculoperitoneal shunts were similar in both groups (4% vs 2%, p = 0.9).
The use of DAPT was associated with a lower risk of clinical vasospasm and DCI in patients treated for aSAH, without an increased risk of hemorrhagic complications.
Daichi Nakagawa, Yasunori Nagahama, Bruno A. Policeni, Madhavan L. Raghavan, Seth I. Dillard, Anna L. Schumacher, Srivats Sarathy, Brian J. Dlouhy, Saul Wilson, Lauren Allan, Henry H. Woo, John Huston III, Harry J. Cloft, Max Wintermark, James C. Torner, Robert D. Brown Jr. and David M. Hasan
Aneurysm growth is considered predictive of future rupture of intracranial aneurysms. However, how accurately neuroradiologists can reliably detect incremental aneurysm growth using clinical MRI is still unknown. The purpose of this study was to assess the agreement rate of detecting aneurysm enlargement employing generally used MRI modalities.
Three silicone flow phantom models, each with 8 aneurysms of various sizes at different sites, were used in this study. The aneurysm models were identical except for an incremental increase in the sizes of the 8 aneurysms, which ranged from 0.4 mm to 2 mm. The phantoms were imaged on 1.5-T and 3-T MRI units with both time-of-flight (TOF) and contrast-enhanced MR angiography. Three independent expert neuroradiologists measured the aneurysms in a blinded manner using different measurement approaches. The individual and agreement detection rates of aneurysm enlargement among the 3 experts were calculated.
The mean detection rate of any increase in any aneurysmal dimension was 95.7%. The detection rates of the 3 observers (observers A, B, and C) were 98.0%, 96.6%, and 92.7%, respectively (p = 0.22). The detection rates of each MRI modality were 91.3% using 1.5-T TOF, 97.2% using 1.5-T with Gd, 95.8% using 3.0-T TOF, and 97.2% using 3.0-T with Gd (p = 0.31). On the other hand, the mean detection rate for aneurysm enlargement was 54.8%. Specifically, the detection rates of observers A, B, and C were 49.0%, 46.1%, and 66.7%, respectively (p = 0.009). As the incremental enlargement value increased, the detection rate for aneurysm enlargement increased. The use of 1.5-T Gd improved the detection rate for small incremental enlargement (e.g., 0.4–1 mm) of the aneurysm (p = 0.04). The location of the aneurysm also affected the detection rate for aneurysm enlargement (p < 0.0001).
The detection rate and interobserver agreement were very high for aneurysm enlargement of 0.4–2 mm. The detection rate for at least 1 increase in any aneurysm dimension did not depend on the choice of MRI modality or measurement protocol. Use of Gd improved the accuracy of measurement. Aneurysm location may influence the accuracy of detecting enlargement.