gms | German Medical Science

72. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC)
Joint Meeting mit der Polnischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

06.06. - 09.06.2021

Validation of haemodynamic CFD-simulations of intracranial aneurysms using intraoperative optical coherence tomography

Validierung hämodynamischer CFD-Simulationen intrakranieller Aneurysmata mittels optischer Kohärenztomographie

Meeting Abstract

  • presenting/speaker Daniel Deuter - Universitätsklinikum Regensburg, Klinik und Poliklinik für Neurochirurgie, Regensburg, Deutschland
  • Alexander Brawanski - Universitätsklinikum Regensburg, Klinik und Poliklinik für Neurochirurgie, Regensburg, Deutschland
  • Andreas Pschierer - Universitätsklinikum Regensburg, Klinik und Poliklinik für Neurochirurgie, Regensburg, Deutschland
  • Thomas Wagner - Universitätsklinikum Regensburg, Klinik und Poliklinik für Neurochirurgie, Regensburg, Deutschland
  • Nils Ole Schmidt - Universitätsklinikum Regensburg, Klinik und Poliklinik für Neurochirurgie, Regensburg, Deutschland
  • Christian Doenitz - Universitätsklinikum Regensburg, Klinik und Poliklinik für Neurochirurgie, Regensburg, Deutschland

Deutsche Gesellschaft für Neurochirurgie. 72. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Polnischen Gesellschaft für Neurochirurgie. sine loco [digital], 06.-09.06.2021. Düsseldorf: German Medical Science GMS Publishing House; 2021. DocV302

doi: 10.3205/21dgnc286, urn:nbn:de:0183-21dgnc2860

Veröffentlicht: 4. Juni 2021

© 2021 Deuter et al.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe http://creativecommons.org/licenses/by/4.0/.


Gliederung

Text

Objective: Computation Fluid Dynamics (CFD) is a well established tool to investigate hemodynamics in vascular geometries. Various authors found correlations between specific CFD-parameters and intraoperatively thin-appearing aneurysm wall regions. Optical Coherence Tomography (OCT), providing tissue images of high local resolution, was already successfully used in cardiology for local intravascular analysis of vessel wall layer composition. The aim of our study was to assess feasibility of intraoperative OCT performed during aneurysm surgery for validation of local wall thicknesses predicted by hemodynamic patterns from CFD simulations.

Methods: We prospectively investigated a series of 4 patients electively undergoing aneurysm surgery. For CFD-simulations, we built patient-specific 3D-volume-meshes based on 3D rotational angiographies using AMIRA 5.6 (FEI Visualization Sciences, France), ANSYS ICEM and CFX (ANSYS Inc., USA). We assumed rigid walls, pulsatile flow and modelled blood as a non-Newtonian fluid with a shear-dependent dynamic viscosity following a Power Law model. Intraoperatively, OCT scans were performed with a ZEISS LUMERA 700 OCT microscope. For postprocessing, ImageJ (https://imagej.nih.gov/) and AMIRA were used. Comparison of local hemodynamic patterns, distribution of parameters like Wall Shear Stress (WSS) and local wall thicknesses were performed in overlay with the intraoperative situs using AVIZO Wind 7.1 (FEI Visualization Sciences).

Results: In all patients, good OCT results were obtained. Thin-appearing translucent areas correlated well with OCT scans. Hemodynamically, low WSS, high pressure and high OSI could be found in these areas. Quantitative measurement of wall thickness was possible and validated intraoperatively using pre-defined plastic sheets. We visualized walls as 3D thickness maps in overlay with the intraoperative view through the microscope. Operating neurosurgeons subjectively profited well from hemodynamic simulations of the individual cases.

Conclusion: We present a novel tool to validate predictions on the local biology of the aneurysm wall derived from hemodynamic CFD-simulations in vivo. CFD-simulations can provide valuable information regarding local thin-walled areas susceptible of rupture serving as a base for a reliable prediction tool for patient-specific aneurysm wall properties and rupture risk. The operating neurosurgeon could concretely benefit from these hemodynamic data to adopt individual dissection strategy to avoid intraoperative rupture.