WEB Device Shape Changes in Elastase-Induced Aneurysms in Rabbits.

BACKGROUND AND PURPOSE: While WEB devices have been shown to be safe and effective for aneurysm treatment, WEB-shape modification compression has been associated with incomplete aneurysm occlusion. We explored the relationship between occlusion rates and WEB-shape modification in different WEB device types in an experimental aneurysm model. MATERIALS AND METHODS: Elastase-induced aneurysms were created in rabbits and treated with dual-layer (n = 12), single-layer (n = 12), or single-layer sphere (n = 12) WEB devices. Aneurysms were followed up either at 3 or 12 months. Angiographic occlusion was graded using the WEB Occlusion Scale: grade I, complete; grade II, complete but recess filling; grade III, residual neck; or grade IV, residual aneurysm. WEB-shape modification and histologic features were also analyzed. RESULTS: Grade I or II occlusion was seen in 16 (44%) aneurysms, and grade I, II, or III ("adequate") occlusion was observed in 22 (61.1%) aneurysms at follow-up. WEB-shape modification was observed in 22 (61.1%) aneurysms. WEB-shape modification was higher in single-layer (9/12) and dual-layer (10/12) devices compared with single-layer sphere devices (3/12). Aneurysms with WEB-shape modification had a higher level of thrombus organization in the dome compared with those without WEB-shape modification (68% [15/22] versus 50% [7/14]). WEB-shape modification was not correlated with angiographic or histologic outcomes but was significantly correlated with levels of fibrosis and smooth muscle cells in the aneurysm. CONCLUSIONS: WEB-shape modification is not associated with incomplete aneurysm occlusion of WEB devices in the rabbit model but may be related to connective tissue formation and the healing response to WEB device implantation.

Evolving Use of fMRI in Medicare Beneficiaries.

Using the Medicare Physician-Supplier Procedure Summary Master File, we evaluated the evolving use of fMRI in Medicare fee-for-service beneficiaries from 2007 through 2017. Annual use rates (per 1,000,000 enrollees) increased from 17.7 to 32.8 through 2014 and have remained static since. Radiologists have remained the dominant specialty group from 2007 to 2017 (86.4% and 88.6% of all services, respectively), and the outpatient setting has remained the dominant place of service (65.4% and 65.4%, respectively).

Efficacy and Safety of the Woven EndoBridge (WEB) Device for the Treatment of Intracranial Aneurysms: A Systematic Review and Meta-Analysis.

BACKGROUND AND PURPOSE: Intrasaccular flow diverters are increasingly being used in the treatment of wide-neck and bifurcation aneurysms. We performed a systematic review and meta-analysis of existing literature on the Woven EndoBridge device in the treatment of intracranial aneurysms. MATERIALS AND METHODS: A comprehensive literature search was performed through October 1, 2015. We extracted information on baseline aneurysm and patient characteristics. Outcomes studied included immediate and midterm (>3 month) angiographic outcomes (complete occlusion as well as adequate occlusion, defined as complete occlusion or neck remnant), aneurysm retreatment, intraoperative rupture, perioperative morbidity and mortality, thromboembolic complications, and treatment failure. Meta-analysis was performed by using the random-effects model. RESULTS: Fifteen uncontrolled series were included in this analysis, including 565 patients with 588 aneurysms, of which 127 were ruptured. Initial complete and adequate occlusion rates were 27% (95% CI, 15%-39%) and 59% (95% CI, 39%-78%), respectively. Midterm complete and adequate occlusion rates after a median of 7 months were 39% (95% CI, 26%-52%) and 85% (95% CI, 78%-91%), respectively. Perioperative morbidity and mortality rates were 4% (95% CI, 1%-8%) and 1% (95% CI, 0%-2%), respectively. Midterm adequate occlusion rates for ruptured aneurysms were 85% (95% CI, 67%-98%), compared with 84% (95% CI, 72%-94%) for unruptured aneurysms (P = .89). Patients with ruptured aneurysm had similar rates of perioperative morbidity to patients with unruptured aneurysm (2%; 95% CI, 0%-26% versus 2%; 95% CI, 0%-6%, respectively; P = .35). CONCLUSIONS: Early evidence derived from uncontrolled studies suggests that Woven EndoBridge treatment has a good safety profile and promising rates of adequate occlusion, especially given the complexity of aneurysms treated. Further prospective clinical trials are needed to confirm these results and better define the risks and benefits of use of the Woven EndoBridge device in treating wide-neck and wide-neck bifurcation aneurysms.