P-029 Longitudinal Monitoring of Flow-diverting Stent Tissue Coverage after Implant Using Neurovascular High Frequency Optical Coherence Tomography

Introduction High frequency optical coherence tomography (HF-OCT) is an intra-vascular imaging modality designed for cerebrovascular anatomy. With a spatial resolution approaching 10 µm, HF-OCT can visualize the interaction between the vessel wall and neurovascular devices in great detail.1, 2 In this study, we sought to evaluate its use to monitor tissue growth over flow diverter stents (FDS) in an arterial bifurcation rabbit model. Materials and methods Six FDS (Pipeline Embolization devices) were deployed in 6 animals, covering the iliac bifurcation. Four animals were treated with double antiplatelet therapy (10 mg/kg aspirin and clopidogrel), 1 with aspirin (10 mg/kg) and 1 was not given any treatment. HF-OCT data were obtained at three different time points per each animal (at implant for all animals then 14 and 60 or 7 and 30 days). For each ostium section, manual segmentation was performed to quantify the percentage of the ostium surface covered by metal and tissue (figure 1A). Results Good quality HF-OCT data sets were successfully acquired in all cases. An average of 35 sections (with a spacing between sections of approximately 70 µm) were analyzed per ostium for each time point. Between 0 and 30 days after implant, HF-OCT analysis showed a significantly higher ostium coverage when DAPT was not given. After 30 days, similar growth rates were found in the DAPT and in the aspirin group (Figure 1B). At 60 days a high 90% coverage rate was reached in both groups. Conclusions HF-OCT enables an accurate visualization of tissue growth over time on FDS struts. HF-OCT imaging can contribute in the pre-clinical evaluation of novel neurovascular devices and, in the near-future, it could potentially contribute to a personalized care, helping the physicians in determining and modulating the ideal antiplatelet regimen for each patient. References Chen C-J, Kumar JS, Chen SH, et al. Optical coherence tomography: future applications in cerebrovascular imaging. Stroke 2018. Gounis MJ, Ughi GJ, Marősfoi M, et al. Intravascular optical coherence tomography for neurointerventional surgery. Stroke 2018. Disclosures J. Caroff: None. G. J. Ughi: 4; C; Gentuity LLC. 5; C; Employee of Gentuity LLC. R. King: None. M. Marosfoi: None. E. Langan: None. M. Gounis: None.