PhD Defence Lisa Rutten | Optical coherence tomography and computational fluid dynamics for peripheral arterial disease

Optical coherence tomography and computational fluid dynamics for peripheral arterial disease

Lisa Rutten is a PhD student in the department Multi-Modality Medical Imaging. (Co)Promotors are prof.dr. M.M.P.J. Reijnen; prof.dr. M. Versluis and dr. K.Jain from the faculty of Sciences & Technology (TNW), University of Twente.

This thesis aimed to improve the treatment of peripheral arterial disease (PAD) in the femoropopliteal tract by investigating advances in treatment planning and by enhancing the understanding and prediction of restenosis after endovascular treatment.

The application of intravascular imaging (Chapter 2) and spectral computed tomography angiography (CTA) based image reconstructions (Chapter 3) for improved visualization of the (stented) femoropopliteal tract were investigated. Differences in intravascular optical coherence tomography (OCT) and CTA-based stenotic and stented geometries (Chapter 4), and differences in one-dimensional Doppler ultrasound (DUS) and two-dimensional contrast-enhanced ultrasound particle image velocimetry (echoPIV) based inlet boundary conditions (IBC) (Chapter 5) were quantified and their effect on CFD-based hemodynamic parameters evaluated. Finally, the impact of OCT imaging on the angiography based pre and post initial treatment plan was investigated in 25 patients with PAD in the femoropopliteal tract (Chapter 6). Intravascular OCT and IVUS were feasible in the femoropopliteal tract and changed the angiography-based treatment plan.

Spectral CTA-based image reconstructions did not reduce stent-induced blooming artifacts. The CTA and OCT-based geometries showed major differences that affected CFD-calculated hemodynamic parameters and restenosis prediction. DUS and echoPIV-derived IBCs differed in inlet velocity profiles and flow rates, but the impact on CFD-calculated hemodynamic parameters was minimal in regions of interest far enough from the inlet and using IBC-specific cut-off values. In conclusion, this thesis demonstrated the impact of intravascular imaging on treatment planning of PAD in the femoropopliteal tract and evaluated the effect of uncertainty in the vessel geometry and flow IBC on CFD-calculated hemodynamic parameters for ISR prediction. These findings have the potential to improve treatment planning and advance the understanding and prediction of restenosis formation, ultimately contributing to improved treatment of PAD in the femoropopliteal tract.