From patient specific aneurysm data to model for computational fluid dynamics

In a study on patient-specific modeling of blood flow in cerebral aneurysms, Novitom played a key role by providing high-resolution synchrotron X-ray microtomography of in vitro aneurysm models treated with endovascular coils.

Using monochromatic radiation at the European Synchrotron Radiation Facility (ESRF), Novitom acquired and segmented 3D datasets at micrometer resolution, free of beam-hardening artifacts. These coil-resolved images enabled researchers to accurately quantify porosity distributions, compute permeability and inertial factors, and validate a new “porous crowns” computational model for aneurysm hemodynamics. Novitom’s imaging expertise was thus central in supplying the reference data needed to bridge clinical imaging limitations and advanced modeling.

A study lead by Alberto Aliseda, University of Washington: Modeling Flow in Cerebral Aneurysm After Coils Embolization Treatment: A Realistic Patient-Specific Porous Model Approach | Cardiovascular Engineering and Technology

Context of the Study : improvement of computational fluid dynamics

The research aimed to improve computational fluid dynamics (CFD) models of blood flow in cerebral aneurysms treated with endovascular coils. A key challenge is that the coil geometry cannot be reconstructed from clinical CT or MRI due to resolution limits and imaging artifacts. To overcome this, the team used synchrotron X-ray microtomography of in vitro patient-specific aneurysm models with real coil deployments. These high-resolution datasets allowed the authors to:

  • Quantify the porosity distribution inside the coiled aneurysms.
  • Calculate permeability and inertial factors needed for porous media modeling.
  • Develop and validate a new “porous crowns” model that better accounts for porosity heterogeneity and improves the accuracy of CFD predictions.

 

Specific Contribution of Novitom : X-ray tomography and segmentation

  • Performed the tomography scans: Novitom conducted synchrotron tomography of the two aneurysm models at the European Synchrotron Radiation Facility ESRF (beamline ID19).

  • Provided high-resolution 3D images: delivery of the datasets with a voxel resolution of 12.92 μm (patient A) and 15.58 μm (patient B), using monochromatic radiation to avoid beam-hardening artifacts.

  • Handled segmentation: Novitom provided the segmented images of the coil geometries. These were later validated by comparing coil volumes from imaging with manufacturer specifications.

  • Enabled the core modeling work: The coil-resolved geometries obtained thanks to Novitom’s tomography were essential as the reference standard against which all porous models (including the new crowns model) were validated.

The research project:

  1. Tomography of patient’s aneurysm with a medical scanner
  2. Footprint in a silicone block : aneurysm model
  3. Insertion of coil / stent within the aneurysm model
  4. Synchrotron tomography and 3D segmentation of porosity
  5. Feed numerical simulations with the coil-reseolved geometries
  6. Surgery of patients

As an independent lab, Novitom enables organisations to access synchrotron micro and nano-tomography :

  • Regular access to instruments at synchrotron facilities
  • Know-how in experimental design for real-time microtomography
  • Expertise in extracting information and physical parameters from raw data and in combination with ancillary techniques

Further reading

Why choose X-ray tomography or microCT?

Why choose X-ray tomography or microCT?

X-ray tomography is now a reference method for non-destructive…