DSA-based rating of aneurysm opacification.

<p>Diagram shows receiver operating characteristic curves for classification of dichotomized neck coverage ratings based on early, intermediate and late phase DSA images. Intrasaccular stasis observed on late phase images had the highest area under the curve for discriminating favorable from unfavorable neck coverage.</p

Model fabrication.

<p>A, Digital subtraction angiography from a patient with a left-sided internal carotid artery aneurysm originating at the posterior communicating artery origin. B, Hollowed surface data after postprocessing, before manufacturing. C, Photograph of the model after manufacturing. D, A single frame from high-frequency digital subtraction angiography in the model, obtained with a MED framer device deployed in the aneurysm sac.</p

Neck coverage.

<p>Upper row shows volume reconstructions from VasoCT of two different MED configurations after implantation in the same aneurysm model (aneurysm 2), viewed from the direction of the aneurysm ostium. Incomplete neck coverage is appreciated in the first configuration (A, top), corresponding to moderate flow velocity reduction (41%) on high-frequency DSA (A, bottom). A different configuration showing better coverage of the neck by the MED petals (B, top) was accompanied by a higher degree of intra-aneurysmal flow velocity reduction (73%, B, bottom).</p

Aneurysm characteristics.

<p>Aneurysm characteristics.</p

Intra-aneurysmal flow disruption after implantation of the Medina^® Embolization Device depends on aneurysm neck coverage

<div><p>Background and purpose</p><p>Flow disruption achieved by braided intrasaccular implants is a novel treatment strategy for cerebrovascular aneurysms. We hypothesized that the degree of intra-aneurysmal flow disruption can be quantified in vitro and is influenced by device position across the aneurysm neck. We tested this hypothesis using the Medina^® Embolization Device (MED).</p><p>Methods</p><p>Ten different patient-specific elastic vascular models were manufactured. Models were connected to a pulsatile flow circuit, filled with a blood-mimicking fluid and treated by two operators using a single MED. Intra-aneurysmal flow velocity was measured using conventional and high-frequency digital subtraction angiography (HF-DSA) before and after each deployment. Aneurysm neck coverage by the implanted devices was assessed with flat detector computed tomography on a three-point Likert scale.</p><p>Results</p><p>A total of 80 individual MED deployments were performed by the two operators. The mean intra-aneurysmal flow velocity reduction after MED implantation was 33.6% (27.5–39.7%). No significant differences in neck coverage (p = 0.99) or flow disruption (p = 0.84) were observed between operators. The degree of flow disruption significantly correlated with neck coverage (ρ = 0.42, 95% CI: 0.21–0.59, p = 0.002) as well as with neck area (ρ = -0,35, 95% CI: -0.54 –-0.13, p = 0.024). On multiple regression analysis, both neck coverage and total neck area were independent predictors of flow disruption.</p><p>Conclusions</p><p>The degree of intra-aneurysmal flow disruption after MED implantation can be quantified in vitro and varies considerably between different aneurysms and different device configurations. Optimal device coverage across the aneurysm neck improves flow disruption and may thus contribute to aneurysm occlusion.</p></div