Background and Purpose-The natural history of unruptured intracranial aneurysms remains unclear, and management strategy is not well defined. Methods-From January 2003 to December 2012, we enrolled patients with aneurysm in our institution. In total, 2252 patients with 2897 aneurysms were eligible for analysis, and 1960 eligible aneurysms were conservatively managed. Precise 3-dimensional evaluation was conducted using computed tomography angiography, digital subtraction angiography, or magnetic resonance angiography. We then assessed the risk of aneurysm rupture, mortality, and morbidity associated with aneurysm characteristics, demographics, and known health/lifestyle risk factors. Results-The mean follow-up duration was 7388 aneurysm-years. During observation, 56 aneurysms ruptured, resulting in an overall rupture rate per year of 0.76% (95% confidence interval, 0.58-0.98). The mean initial visit to rupture interval was 547 days. Aneurysm size, location, daughter sac, and history of subarachnoid hemorrhage were significant independent predictors for aneurysm rupture. Aneurysms that were ≥5 mm were associated with a significantly increased risk of rupture when compared with 2-to 4-mm aneurysms (unadjusted hazard ratio, 12.24; 95% confidence interval, 7.15-20.93). Of 56 patients who experienced hemorrhage, 29 (52 %) died or were rendered severely disabled. Of the patients who had large or giant aneurysms, none recovered without deficits, and the mortality rate after rupture was 69%. For aneurysms sized <5 mm, the mortality rate was 18%. Conclusions-Larger

Backgrounds and Purpose-The authors evaluated the incidence of rupture of unruptured intracranial saccular aneurysm during observation. Methods-Between January 2003 and December 2006, a total of 419 patients with 529 unruptured intracranial saccular aneurysms were observed without treatment. The mean follow-up duration was 905.3 days. Aneurysm size was measured by 3-dimensional CT angiography. Clinical and 3-dimensional CT angiography follow-up were obtained every 6 months. Results-Nineteen aneurysms ruptured during observation resulting in a 1.4% rupture rate per year. A history of subarachnoid hemorrhage (hazard ratio, 7.3; 95% CI, 2.5 to 21.2), posterior circulation aneurysm (hazard ratio, 2.9; 95% CI, 1.1 to 8), and large size were significant independent predictors for aneurysm rupture. Conclusions Clinical Materials and MethodsFrom January 2003 through December 2006, a total of 419 patients with 529 UIAs were referred to our institution. Patient information and clinical presentation is summarized in Table 1.Size of the UIAs was measured by 3-dimensional CT angiography (Sensation16, Siemens, Germany). Based on the findings of 3-dimensional CT angiography, all UIAs were classified into the following categories: small (S; 0 to 4.9 mm in diameter), medium/ small (MS; 5 to 9.9 mm in diameter with small neck (0 to 3.9 mm), medium/wide (MW; 5 to 9.9 mm in diameter) with a wide neck (Ͼ4 mm), large (L; Ͼ10 mm), and giant (G; Ͼ25 mm). These aneurysms were followed by 3-dimensional CT angiography every 6 months.Data were analyzed using the biomedical data package statistical program (Version 7.0; BMDP Statistical Software, Inc, University of California, Los Angeles, Calif). Categorical variables were compared using the Fisher exact 2-tailed test, the Pearson 2 test, or the test for determining linear trend. Continuous variables were compared among groups by using the Mann-Whitney U test or the Student t test. For life-table analysis and Cox proportional hazards regression model, each patient was followed to the time of subarachnoid hemorrhage (SAH), death due to causes other than SAH, or to the last possible follow-up contact. The average annual incidence of SAH was calculated by determining the number of first-event SAH divided by the number of person-years of follow-up. Cumulative rates of SAH were estimated using the Kaplan-Meier product-limit method. ResultsNineteen aneurysms ruptured during the follow-up period. The annual incidence of SAH was 1.4% during observation. Incidence of rupture was strongly correlated with aneurysm size. The annual rupture rate by size classification was 0.8% (S), 1.2% (M), 7.1% (L), and 43.1% (G), respectively. Details of ruptured aneurysms under conservative observation are summarized in Table 2.In patients with a history of SAH, the hazard ratio (HR) was 7.3 (95% CI, 2.5 to 21.2, PϽ0.001). Particularly in S-sized UIAs, 2 of 8 (25%) were associated with a history of SAH. The risk of rupture in S-sized UIAs with a history of SAH was 5.5 (95% CI, 0.9 to 32.4) compared with patients ...

This newly developed robotic DSA system provides safe and precise treatment in the fields of endovascular treatment and neurosurgery.

Background and Purpose-Transcranial ultrasound (TUS) enhances thrombolysis and is expected to be useful for the treatment of ischemic stroke. However, neither its effectiveness in improving neurologic outcome nor its safety in living tissue has been fully established. We examined the efficacy and safety of low-frequency TUS under appropriate conditions of ultrasound for thrombolytic treatment in a rat middle cerebral artery stroke model. Methods-Sixty-five male Wistar rats were used. Rats with right middle cerebral artery stroke exhibiting left hemiparesis were blindly selected and randomly assigned to 1 of 3 groups: (1) control, no therapy; (2) tPA, intravenous administration of tissue plasminogen activator 3 hours after middle cerebral artery stroke, or (3) TUS, tPA administration and application of TUS (490 kHz, continuous wave, at an intensity of 0.8 W/cm 2 ). Twenty-four hours after the onset of stroke, neurologic improvement was evaluated and brains were then removed. Thrombolysis at the origin of the right middle cerebral artery was examined. Thrombolysis ratio, cerebral infarct ratio, and rate of histologic evidence of hemorrhage were compared in the 3 groups. Results-Significantly better neurologic improvement (Pϭ0.008), a higher thrombolysis ratio (Pϭ0.041), and a reduction of cerebral infarct volume (Pϭ0.047) were obtained in the TUS group compared with the tPA group, without an increase in hemorrhagic transformation. Conclusions-Our findings suggest that thrombolytic treatment with low-frequency TUS under appropriate conditions could be an effective and safe method of treatment for ischemic stroke.

The newly designed endovascular OR facilitates safe and systemic treatment of neurovascular disease.

DynaCT has the potential to be used as a powerful tool for endovascular and neurosurgical procedures and will open new possibilities for neurosurgical management.

Thromboembolic events was most important adverse event for coil embolization for intracerebral aneurysm. The present study investigated possible risk factors for thromboembolic events during coil embolization using diffusion-weighted imaging (DWI), comparing unruptured and ruptured lesions.

Modern imaging technologies, such as computed tomography (CT) angiography, magnetic resonance (MR) angiography, and digital subtraction (DS) angiography are widely used for pretreatment evaluation of cerebral aneurysms, but the relative accuracies of these modalities are unclear. This study compared the measurements of aneurysm neck and dome height and width on CT angiography, time-offlight (TOF)-MR angiography, and DS angiography using a three-dimensional workstation. An elastic model of a side-wall aneurysm was connected to an artificial heart pulsatile circuit system. The aneurysm model was prepared using a silicone membrane of 0.6-mm thickness under normal physiological circulation parameters. Using this aneurysm model, three-dimensional TOF-MR angiography, contrast-enhanced CT angiography, and DS angiography were performed. Source images were postprocessed on a dedicated workstation to calculate the aneurysm size. DS angiography measurements were found to be the most accurate. In contrast, aneurysm neck sizes measured on CT angiography were significantly wider than actual values (p º 0.05) and aneurysm heights measured using TOF-MR angiography were significantly lower than actual values (p º 0.01). In this in-vitro model, at least one aneurysm dimension measured with CT angiography and with TOF-MR angiography differed significantly from actual values. Aneurysm neck width markedly affects therapeutic planning, as a wide neck requires craniotomy or endovascular treatment using an adjunctive device, so inaccuracies should be considered when aneurysm treatment is planned using modern methods of visualization.