Clinical Research & Publications

Purpose: During follow-up of patients treated with WEB devices, shape changes have been observed. The quantitative three-dimensional measurement of the WEB shape modification (WSM) would offer useful information to be studied in association with the anatomical results and try to better understand mechanisms implicated in this modification phenomenon.

ABSTRACT Purpose It is unclear how flow diverters (FDs) and vessels interact in the treatment of intracranial aneurysms. In this study, we examine the local changes in artery and device morphology caused by their mutual interaction. Methods Pre-treatment 3DRA and post-treatment XperCT or DynaCT images were collected retrospectively from 25 patients. Vessel anatomies and FD models were obtained by segmenting the corresponding images. Perpendicular cross-sections of vessels and FDs were extracted and described in terms of area, perimeter, and circularity. The geometrical parameters from each vessel were paired point-by-point with those from FDs. Results FD cross-sections are typically circular, regardless of the vessel’s morphology. The area and perimeter of FD cross-sections were smaller than those of the vessel in 66.8% of the data; however, they were larger in 30.1%, suggesting that the vessel is radially stretching to accommodate the FD expansion. In 3.1% of the slices, the FD area was larger than the vessel, but its perimeter was smaller, indicating a change in the shape of the artery. Conclusions Expansion of FD is generally restricted by the morphology of the vessel, but the vessel is also able to adapt to the device by changing its shape or stretching.

Flow diverters are widely extended in clinical practice for intracraneal aneurysms treatment. They are formed by a dense mesh of braided wires that partially occludes the aneurysm neck and restores the blood flow into the parent vessel. The occlusion degree is highly dependant on the distribution of the wires under the aneurysm, which is affected by the vessel geometry. Nowadays, there are no clinical indicators of the covering ratio once the flow diverter is deployed.

Flow diverter porosity directly influences the blood flow reduction at the aneurysm neck level and the anatomical result of the treatment. In this research, we present and compare three methodologies to determine the local porosity of deployed flow diverters.

Flow diverters (FDs) have revolutionized intracranial aneurysm (IA) treatment. Proper FD sizing is crucial for aneurysm occlusion and complication prevention. Ankyras (Mentice, Gothenburg, Sweden) is a device-specific sizing software. We evaluated Ankyras’ performance in predicting the final deployment of the Pipeline™ Vantage Embolization Device with Shield Technology™ (PVST) (Medtronic Neurovascular, Irvine, California, USA).

Background: Accurate device sizing is crucial for successful flow diverter (FD) therapy in intracranial aneurysms. This study assesses the accuracy and clinical utility of the Ankyras virtual simulation software (Mentice AB, Gothenburg, Sweden) in predicting FD length across multiple device types and manufacturers. Methods: We retrospectively analyzed 193 FDs (7 device types) deployed in 180 patients with 230 intracranial aneurysms. Simulation-based prediction of effective lengths (simulated length (SL)) and nominal manufacturer specifications (labeled length) were compared with measured in vivo lengths (measured length (ML)). Performance was evaluated using simulation accuracy (SA), absolute error (AE), relative error (RE), length ratio, and correlation analysis. Results: Virtual simulation demonstrated good clinical usability, achieving a mean absolute deviation of only -1.38 mm at the proximal landing zone compared with ML. Simulation-based predictions showed significantly superior accuracy compared with nominal manufacturer specifications (SA 89.6±11.3% vs 81.8±13.7%, P<0.001), with mean AE reduced by 58% (-1.38 mm vs -3.34 mm) and mean RE by 42% (10.5% vs 18.2%). Strong correlations between SL and ML (r=0.900) validated predictive reliability across all tested device types. Centerline correction technology further enhanced parameters such as SA to 94.8±9.5%. Conclusion: Virtual simulation-based prediction of effective FD length using the Ankyras software showed reliable and clinically meaningful results, enabling accurate estimations of the proximal landing zone and overall length. Ankyras, along with comparable simulation platforms, may provide considerable potential to facilitate FD selection and implementation, especially in anatomically complex cases.

Background: Accurate flow diverter (FD) sizing is critical for successful intracranial aneurysm (IA) treatment. We evaluated the predictive performance of the Ankyras FD simulation platform within a standardized simulation based clinical workflow using three-dimensional (3D) DynaCTA centerline analysis as an advanced validation reference standard. Methods: A retrospective analysis of a prospectively maintained institutional database of Ankyras guided IA treatments between April 2024 and October 2025 was performed. 3D rotational angiography data generated Ankyras simulations for treatment planning, device selection, and intraoperative guidance. Simulated length (SL) and proximal landing zone (PLZ) were compared with post-deployment length (DL) from DynaCTA centerline measurements (3D Slicer). Accuracy was assessed using correlation coefficients, mean absolute error (MAE), and Bland-Altman analysis. Results: 54 consecutive patients (48 women, mean age 54.2 years) with 63 IAs underwent 57 pipeline embolization device (PED) treatments. All achieved procedural success without intraoperative complications; two required adjunctive stent placement for malapposition. Mean SL was 21.44±3.53 mm and DL was 21.49±3.52 mm (n=46), with a strong SL-DL correlation (r=0.91), minimal bias (-0.05 mm), and 1.24 mm MAE. PLZ demonstrated a strong correlation (r=0.94), low bias (0.14 mm), and minimal MAE (1.34 mm) between Ankyras and the deployed values (n=45). Bland-Altman analysis showed narrow agreement limits without evidence of proportional error. Conclusions: Using a robust 3D DynaCTA centerline based validation, Ankyras demonstrated high accuracy for PED deployment length and landing zone prediction within a standardized clinical treatment workflow of pre-procedural planning, intraoperative guidance, and post-deployment assessment.

An important issue in the deployment of braided stents, such as flow diverters, is the change in length, also known as foreshortening, underwent by the device when is released from the catheter into a blood vessel. The position of the distal end is controlled by the interventionist, but knowing a priori the position of the proximal end of the device is not trivial.

Intra-saccular devices (ID) are novel braided devices used for complex intracranial aneurysms treatment. Treatment success is associated with correct device size selection. A technique that predicts the ID size within the aneurysm before intervention will provide a powerful computational tool to aid the interventionist during device selection.

Flow-Diverter (FD) porosity has been pointed as a critical factor in the occlusion of cerebral aneurysms after treatment. Objective: Verification and Validation of computational models in terms of predictive capacity, relating FD porosity and occlusion after cerebral aneurysms treatment.

Intra-saccular devices (ID), developed for the treatment of bifurcation aneurysms, offer new alternatives for treating complex terminal and bifurcation aneurysms. In this work, a complete workflow going from medical images to post-treatment CFD analysis is described and used in the assessment of a concrete clinical problem.

Validate the use of a software-based simulation for pre-assessment of braided self-expanding stents in the treatment of wide-necked intracranial aneurysms

Sizing of flow diverters (FDs) stent in the treatment of intracranial aneurysms is a challenging task due to the change of stent length after implantation

Flow diverter (FD) devices show severe shortening during deployment in dependency of the vessel geometry. Valid information regarding the geometry of the targeted vessel is therefore mandatory for correct device selection, and to avoid complications. But the geometry of diseased tortuous intracranial vessels cannot be measured accurately with standard methods. The goal of this study is to prove the accuracy of a novel virtual stenting method in prediction of the behavior of a FD in an individual vessel geometry.

Intrasaccular devices, like Woven EndoBridge (WEB), are novel braided devices employed for the treatment of aneurysms with a complex shape and location, mostly terminal aneurysms. Such aneurysms are often challenging or impossible to treat with other endovascular techniques such as coils, stents, flow diverter stents.

Different computational methods have been recently proposed to simulate the virtual deployment of a braided stent inside a patient vasculature. Those methods are primarily based on the segmentation of the region of interest to obtain the local vessel morphology descriptors. The goal of this work is to evaluate the influence of the segmentation quality on the method named "Braided Device Foreshortening" (BDF).

Flow diverters are widely extended in clinical practice for intracraneal aneurysms treatment. They are formed by a dense mesh of braided wires that partially occludes the aneurysm neck and restores the blood flow into the parent vessel. The occlusion degree is highly dependant on the distribution of the wires under the aneurysm, which is affected by the vessel geometry. Nowadays, there are no clinical indicators of the covering ratio once the flow diverter is deployed. We propose a novel method for the simulation of the flow diverter local porosity before its deployment into the parent vessel. We validate the method on curved silicon models, obtaining a correlation of 0.9 between the simulated values and the measured porosity on the deployed flow diverter.