Presence Of Unruptured Intracranial Aneurysms Research Articles

Role of aneurysmal hemodynamic changes in pathogenesis of headaches associated with unruptured cerebral aneurysms.

One symptom commonly associated with the presence of unruptured intracranial aneurysms is headache. In this study, the authors aimed to analyze factors associated with headaches among patients with intracranial aneurysms, with special consideration of hemodynamic parameters. The authors prospectively included 96 patients with 122 unruptured intracranial aneurysms. The authors obtained detailed medical history including current diseases and medications, as well as blood pressure values taken during hospitalization from the patients' medical records. The short-form McGill Pain Questionnaire was administered to each patient at admission and 3-6 months after the procedure to assess type and severity of headache. Based on imaging data, the authors obtained 3D reconstruction of each patients' aneurysm dome with feeding artery. The authors performed computational fluid dynamics analysis of blood flow through prepared models using OpenFOAM. Blood was modeled as Newtonian fluid, using the incompressible transient solver. Patient-specific internal carotid artery (ICA) blood velocity waves obtained with Doppler ultrasound were set as inlet boundary conditions. After performing simulation, the authors calculated the hemodynamic parameters of the aneurysm dome. A total of 30 patients (31.25%) reported having headaches. In multivariate logistic regression analysis, female sex (OR 2.81, 95% CI 2.51-4.86; p < 0.01), ICA aneurysm location (OR 7.93, 95% CI 5.51-8.52; p < 0.01), multiple aneurysms (OR 6.05, 95% CI 1.83-11.83; p = 0.02), mean dome blood velocity (OR 3.10, 95% CI 2.01-3.30; p < 0.01) and time-averaged wall shear stress (OR 1.18, 95% CI 1.47-2.72; p = 0.04) were independently associated with the presence of headache. Additionally, 17 patients (56.67%) reported complete relief of symptoms after the procedure. In multivariate logistic regression analysis, the mean blood flow in the ICA was independently associated with complete resolution of headaches after aneurysm treatment (OR 2.32, 95% CI 1.57-3.28; p < 0.01). Hemodynamic parameters of intracranial aneurysms might be associated with headaches and their relief after aneurysm treatment.

Performance of a Diagnostic Model for the Presence of Unruptured Intracranial Aneurysms in the General Population

Plain Language SummaryA burst of a blood vessel in the brain, also known as a ruptured intracranial aneurysm, causes a severe and often fatal type of stroke (aneurysmal subarachnoid hemorrhage). When such an aneurysm has not ruptured yet, it is called an unruptured intracranial aneurysm (UIA). Approximately 3% of persons in the general population have a UIA. We developed models to help identify persons in the general population at high risk of having a UIA. These models show which person characteristics predict the risk of having a UIA. We developed a model for the whole general population and for men and women separately. We found that in the whole general population, female sex, higher age, high blood pressure, and smoking increased the risk of having a UIA, while diabetes decreased this risk. For men separately, only higher age, high blood pressure, and smoking increased the risk of having a UIA. For women separately, only smoking increased the risk of having a UIA. However, the models had insufficient performance to help identify persons at high risk of having a UIA from other persons in the general population. Rather, they provide insight into risk factors contributing to UIA risk and show that these may be in part sex-specific.

Rupture pressure values of cerebral arteries in the presence of unruptured intracranial aneurysm

Cerebral arteries (CAs) are prone to the saccular aneurysm formation. Since aneurysms may be considered as balloon-like dilations of the locally weakened arterial wall, it should be determined whether the presence of intracranial aneurysm is related to the generalized weakening of CAs. Among 184 consecutive forensic autopsies, eight brains with a single unruptured saccular aneurysm were identified. Aneurysms with adjacent CAs and specific CA segments were excised, namely: the anterior communicating artery complex, and bifurcations of the basilar artery, internal carotid arteries, and middle cerebral arteries. Then, aneurysm and CA specimens were subjected to pressure-inflation tests until rupture occurred at the arterial bifurcation or at the wall of the CA or aneurysm. The same protocol was applied to the control group composed of CAs excised from eight brains without aneurysm. No significant differences were noted between the experimental and control groups, depending on the mean rupture pressure (1054 vs. 1048 mmHg) and rupture site (bifurcation vs. wall) of the analyzed specimens. These findings indicate that the presence of unruptured saccular aneurysm is not related to generalized weakening of CAs among autopsy subjects. Moreover, the CA bifurcations do not represent regions of decreased wall strength.

Low Carotid Flow Pulsatility Index Correlates With the Presence of Unruptured Intracranial Aneurysms.

BackgroundWe assessed cases of incidental unruptured intracranial aneurysm (UIA) discovered on screening magnetic resonance angiography to identify hemodynamic and atherosclerotic risk factors.Methods and ResultsThe data of 1376 healthy older subjects (age range, 31–91 years) without cerebro‐ or cardiovascular diseases who underwent brain magnetic resonance angiography as part of a medical checkup program at a health screening center were examined retrospectively. We looked for an increase in classical risk factors for UIAs (age, sex, hypertension, and smoking) and laboratory data related to lifestyle diseases among subjects with UIAs. Brachial‐ankle pulse wave velocity, central systolic blood pressure, radial augmentation index, and carotid flow pulsatility index were also compared between those with and without UIAs. We found UIAs in 79 (5.7%) of the subjects. Mean age was 67.1±9.0 years, and 55 (70%) were women. Of the 79 aneurysms, 75 (95%) were in the anterior circulation, with a mean diameter of 3.1 mm (range, 2.0–8.0 mm). Subjects with UIAs were significantly older and had more severe hypertension. The carotid flow pulsatility index was significantly lower in subjects with UIAs and negatively and independently correlated with UIAs. Tertile analysis stratified by carotid flow pulsatility index revealed that subjects with lower indices had higher levels of low‐density lipoprotein cholesterol.ConclusionsThe presence of UIAs correlated with lower carotid flow pulsatility index and elevated low‐density lipoprotein cholesterol in the data from a population of healthy older volunteers. A reduced carotid flow pulsatility index may affect low‐density lipoprotein cholesterol elevation by some molecular pathways and influence the development of cerebral aneurysms. This may guide aneurysm screening indications for institutions where magnetic resonance angiography is not routine.

Determinants of the Presence and Size of Intracranial Aneurysms in the General Population: The Rotterdam Study.

The prevalence of unruptured intracranial aneurysms (UIAs) in the adult population is ≈3%. Rupture of an intracranial aneurysm can have devastating consequences, which emphasizes the importance of identification of potentially modifiable determinants for the presence and size of UIAs. Our aim was to study the association of a broad spectrum of potential determinants with the presence and size of UIAs in a general adult population. Between 2005 and 2015, 5841 participants from the population-based Rotterdam Study (mean age, 64.4 years, 45.0% male) underwent brain magnetic resonance imaging (1.5T). These scans were evaluated for the presence of incidental UIAs. We determined number and volume of the UIAs. Using logistic and linear regression models, we assessed the association of cardiovascular, lifestyle and emerging inflammatory and hormonal determinants with the presence and volume of UIAs. In 134 (2.3%) participants, ≥1 UIAs were detected (149 UIAs in total), with a median volume of 61.1 mm3 (interquartile range, 33.2-134.0). In multivariable models, female sex (odds ratio, 1.92 [95% CI, 1.33-2.84]), hypertension (odds ratio, 1.73 [95% CI, 1.13-2.68]), and current smoking (odds ratio, 3.75 [95% CI, 2.27-6.33]) were associated with the presence of UIAs. We found no association of alcohol use, physical activity, or diet quality with UIA presence. Finally, we found white blood cell count to relate to larger aneurysm volume (difference in volume of 33.6 mm3 per 109/L increase in white blood cell [95% CI, 3.92-63.5]). In this population-based study, female sex, hypertension, and smoking, but no other lifestyle determinants, were associated with the presence of UIAs. White blood cell count is associated with size of UIAs. Preventive strategies should focus on treating hypertension and promoting cessation of smoking.

Can low cerebrospinal fluid S-100 protein concentration indicate the presence of unruptured intracranial aneurysm? – A preliminary study

Can low cerebrospinal fluid S-100 protein concentration indicate the presence of unruptured intracranial aneurysm? – A preliminary study

Safety of antithrombotic therapy for patients with acute ischemic stroke harboring unruptured intracranial aneurysm.

Background The safety of antithrombotic therapy for patients with acute ischemic stroke harboring unruptured intracranial aneurysms remains unclear. Aims This study was performed to determine whether treatment with antiplatelets, anticoagulants, or intravenous thrombolytic agents is safe for patients with acute ischemic stroke and unruptured intracranial aneurysms. Methods Among 9149 patients with acute ischemic stroke enrolled in the Fukuoka Stroke Registry from June 2007 to December 2014, 8857 patients with data on cerebrovascular imaging and three-month outcomes were included in this study. The frequency of adverse events, including intracranial hemorrhage, symptomatic intracranial hemorrhage, and in-hospital mortality, was compared between patients with and without unruptured intracranial aneurysms. The risk of a poor functional outcome (modified Rankin scale score of ≥3) at three months after stroke onset was estimated after adjusting for confounding factors by logistic regression analysis. Results Unruptured intracranial aneurysms were identified in 412 (4.7%) patients, and the mean diameter was 4.1 ± 3.2 mm. There was no significant difference in the frequency of any adverse events between patients with and without unruptured intracranial aneurysms among the overall patients or patients receiving antiplatelets, anticoagulants, or intravenous thrombolytic agents. The odds ratios of a poor functional outcome were not significantly higher in the presence of unruptured intracranial aneurysms, even in patients undergoing antiplatelet therapy, anticoagulation therapy, or intravenous thrombolysis. Conclusions These findings suggest that unruptured intracranial aneurysms are not associated with increased risks of adverse events or poor functional outcomes even after antithrombotic therapy for acute ischemic stroke. However, accumulation of cases is required to verify these findings.

Abstract TMP1: International Multicenter Study Demonstrating Safety of Intravenous Thrombolysis in Acute Ischemic Stroke Patients Harboring Unruptured Intracranial Aneurysms

Objective: We sought to determine the safety of intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) patients harboring unruptured intracranial aneurysm (UIA) in a prospective, multi-center study. Methods: We prospectively analyzed data from consecutive AIS treated with IVT during a 4-year period at four tertiary-care stroke centers. All patients routinely underwent CT or MR angiography during hospitalization. The presence of UIA was documented on the basis of neuroradiology reports. Symptomatic intracranial hemorrhage (sICH) was defined as imaging evidence of ICH combined with an increase in NIHSS-score of ≥4 points. Results: Our multicenter study evaluated a total of 1398 AIS patients treated with IVT with available neurovascular imaging data. The presence of concomitant UIAs was identified in 42 cases (3.0%, 95%CI by adjusted Wald method: 2.2%-4.1%) harboring a total of 48 IAs. Four of the forty-two (8%) AIS patients had multiple aneurysms. The mean maximum diameter of UIA was 4.3±2.7mm ranging between 2-15 mm. Nearly all UIA were saccular (45/48, 94%) and the majority were located in the anterior circulation (29/48; 61%). The maximum diameter was ≥7mm and ≥10mm in 6 (12.5%) and 3 (6.3%) cases respectively. The rates of symptomatic and asymptomatic ICH were 2.4% (95%CI by adjusted Wald method: 0%-12.6%) and 7.1% (95%CI by adjusted Wald method: 1.8%-19.7%) respectively. The single sICH reported in our multi-center study was not caused by aneurysmal rupture, since the incidental aneurysm was located in the posterior communicating artery in the hemisphere that was contralateral to the sICH. The rates of in-hospital mortality and favorable functional outcome at hospital discharge (defined as modified Rankin Scale score of 0-1) were 2.4% (95%CI by adjusted Wald method: 0%-12.6%) and 50.0% (95%CI by adjusted Wald method: 35.5%-64.5%) respectively. Conclusions: Our prospectively collected multi-center data indicate the potential safety of IVT in AIS patients with UIA.

Risk Factors Associated With the Presence of Unruptured Intracranial Aneurysms.

With the increased investigation of cerebral arteries using magnetic resonance angiography in the general population, the detection of unruptured intracranial aneurysms (UIAs) has increased. Understanding the distribution and factors associated with UIAs might be helpful for understanding the pathomechanism. Subjects who underwent magnetic resonance angiography with a health examination at the Health Screening and Promotion Center were enrolled. The incidence and risk factors of UIAs (age, sex, hypertension, diabetes mellitus, smoking, alcohol, and coronary artery disease) were investigated by comparing patients with and without UIAs. These risk factors were also investigated by the UIA location, distal internal carotid artery, anterior cerebral artery and middle cerebral artery (MCA), MCA bifurcation, anterior and posterior communicating artery, and posterior circulation. Among 187 166 subjects who received health examination, 18 954 underwent magnetic resonance angiography. Of them, 367 (1.93%) had UIAs. Age (odds ratio [OR], 1.02; P=0.003), women (OR, 2.00; P<0.001), hypertension (OR, 2.21; P<0.001), smoking (OR, 1.66; P=0.001), and coronary artery disease (OR, 0.23; P<0.001) were independently associated with the presence of UIAs. Hypertension was associated with most UIAs, except for those located at sidewalls (anterior cerebral artery and MCA). MCA aneurysms were associated with old age and smoking. Distal internal carotid artery, posterior communicating artery, and MCA-bifurcation aneurysms were associated with female sex. Anterior communicating artery aneurysms were associated with smoking and alcohol. Posterior circulation UIAs were only associated with hypertension. Coronary artery disease was negatively associated with anterior circulation aneurysms. The risk factors for UIAs differ by their location, compared with the control. Interestingly, the presence of coronary artery disease was protective against the presence of UIAs.

Successful Thrombolysis despite Having an Incidental Unruptured Cerebral Aneurysm.

Purpose. To report a case of successful thrombolysis performed in a patient with an incidental unruptured intracranial aneurysm and review the literature. Case Report. Patient admitted for ischemic stroke due to left posterior cerebral artery occlusion, with an incidental right middle cerebral artery aneurysm, who underwent treatment with tissue plasminogen activator (rtPA) resulting in clinical improvement without complications. Conclusion. The presence of unruptured intracranial aneurysms is considered as a contraindication to thrombolysis, due to a potentially higher hemorrhagic risk of aneurysm rupture. Patients, otherwise, eligible for thrombolysis are usually excluded from receiving this emergent treatment, despite its potential benefits. A reevaluation of the strict exclusion criteria for thrombolysis in acute stroke patients should be considered.

Safety of Intravenous Thrombolysis in Acute Ischemic Stroke Patients with Saccular Intracranial Aneurysms

It is not known if the presence of unruptured intracranial aneurysms can increase the risk of hemorrhage after thrombolysis for acute ischemic stroke. The goal of our study was to evaluate the risk of hemorrhage after intravenous tissue plasminogen activator in acute stroke patients with intracranial aneurysms. This is a retrospective analysis of consecutive cases of patients with acute ischemic stroke who were treated with intravenous tissue plasminogen activator at Mayo Clinic between March 2002 and June 2011 and who were evaluated with invasive or noninvasive intracranial angiography. Univariate analyses were performed with the t, Chi-square, and Fisher exact tests where appropriate. Intracranial angiograms were performed in 105 patients (85 magnetic resonance angiography, 19 computed tomography angiography, and 1 catheter arteriography). The mean age of the patients was 69 ± 14 years. The mean National Institutes of Health Stroke Scale score at admission was 8 ± 5. A total of 12 incidental saccular aneurysms were found in 10 (9.5%) patients, and all 10 of these patients were white. There were no subarachnoid hemorrhages during the hospital stay in any patient with or without intracranial aneurysm. The rates of symptomatic intracranial hemorrhage and 3-month clinical outcomes were similar in patients with or without intracranial aneurysms. Intravenous thrombolysis was safe among our patients with acute ischemic stroke and incidental intracranial saccular aneurysm.

The Natural History and Treatment Options for Unruptured Intracranial Aneurysms

Recent advances in angiographic technique have raised our awareness of the presence of unruptured intracranial aneurysms (UIAs). However, the appropriate management for these lesions remains controversial. To optimize patient outcomes, the physician must weigh aneurysmal rupture risk associated with observation against the complication risks associated with intervention. In the case that treatment is chosen, the two available options are surgical clipping and endovascular coiling. Our paper summarizes the current body of literature in regards to the natural history of UIAs, the evolution of the lesion if it progresses uninterrupted, as well as the safety and efficacy of both treatment options. The risks and benefits of treatment and conservative management need to be evaluated on an individual basis and are greatly effected by both patient-specific and aneurysm-specific factors, which are presented in this paper. Ultimately, this body of data has led to multiple sets of treatment guidelines, which we have summated and presented in this paper.

Magnitude and Role of Wall Shear Stress on Cerebral Aneurysm. Computational Fluid Dynamic Study of 20 Middle Cerebral Artery Aneurysms

Magnitude and Role of Wall Shear Stress on Cerebral Aneurysm. Computational Fluid Dynamic Study of 20 Middle Cerebral Artery Aneurysms

Abstracts of literature

Abstracts of literature

Initial and follow-up screening for aneurysms in families with familial subarachnoid hemorrhage.

In families with two or more relatives with subarachnoid hemorrhage (SAH), other first-degree relatives have an increased risk of SAH. We studied the presence of unruptured intracranial aneurysms in 125 members of 23 families with familial SAH, defined as two or more affected first-degree relatives, in a cross-sectional design. MR angiography was performed in 116 relatives; CT angiography was performed in the remaining 9 relatives because they had been treated for intracranial aneurysms in the past. Overall, we found 16 aneurysms in 10 of 125 relatives (8%; 95% CI, 4 to 14%). Of the nine patients with previous surgery for ruptured or unruptured intracranial aneurysms, three had new aneurysms. Two factors were associated with a significantly higher risk of intracranial aneurysms: 1) a history of treatment for ruptured or unruptured intracranial aneurysms (relative risk 5.5; 95% CI, 1.7 to 17.8) and 2) having three or more affected relatives (relative risk 3.3; 95% CI, 1.0 to 10.6). Siblings tended to have a higher risk of intracranial aneurysms than did children of SAH patients, although the difference was not significant. Because the yield is high, screening is recommended in first-degree members of families with familial SAH. Repeated screening should be considered in relatives who have been treated for familial intracranial aneurysms.