In Vivo Imaging of Novel Tungsten Nanoparticle and Polymer-infused Resorbable Inferior Vena Cava Filters in Porcine Model

Wednesday, March 8, 2023

3:18 PM – 3:27 PM

Location: Phoenix Convention Center, 225AB

Abstract Speaker(s)

Erin Marie San Valentin (she/her/hers)

Graduate Student
Department of Interventional Radiology at The University of Texas MD Anderson Cancer Center

Disclosure(s): No financial relationships to disclose

Author/Co-author(s)

JD

Jossana Damasco, n/a

Postdoctoral Fellow
Department of Interventional Radiology at The University of Texas MD Anderson Cancer Center
MB

Marvin Bernardino, n/a

Research Investigator
Department of Interventional Radiology at The University of Texas MD Anderson Cancer Center
Sarah Honegger

Undergraduate
University of Notre Dame
KC

Karem Court, n/a

Postdoctoral Fellow
Houston Methodist Research Institute
BG

Biana Godin, n/a

Assistant Professor
Houston Methodist Research Institute
GC

Gino Canlas, n/a

Instructor
Lamar University
GC

Gouthami Chintalapani, PhD

Senior Staff Scientist
Siemens Healthineers
WN

William Norton, DVM

Associate Professor
Department of Veterinary Medicine at The University of Texas MD Anderson Cancer Center
Stephen R. Chen, MD

Associate Professor
MD Anderson Cancer Center
NF

Natalie Fowlkes, DVM, PhD

Assistant Professor
Department of Veterinary Medicine at The University of Texas MD Anderson Cancer Center
Steven Y. Huang, MD

Professor
Department of Interventional Radiology at The University of Texas MD Anderson Cancer Center
Marites P. Melancon, PhD

Associate Professor
Department of Interventional Radiology at The University of Texas MD Anderson Cancer Center

Disclosure(s):

Erin Marie San Valentin: No financial relationships to disclose

Sarah Honegger: No financial relationships to disclose

Stephen R. Chen, MD: Balt USA: Advisory Committee or Review Panel Member (Ongoing); Boston Scientific / Biocompatibles BTG: Advisory Committee or Review Panel Member (Terminated, December 21, 2021); PENUMBRA INC: Speaking and Teaching (Terminated, December 3, 2022)

Steven Y. Huang, MD: No financial relationships to disclose

Marites P. Melancon, PhD: No financial relationships to disclose

Purpose: Placement of inferior vena cava filters (IVCFs) are recommended for patients suffering from deep vein thrombosis or pulmonary embolism but with contraindications to anticoagulation. As non-retrieval of IVCFs pose risks of IVCF migration, embolization, and thrombosis, absorbable IVCFs constructed with poly-p-dioxanone (PPDO) was developed {1}. However, in order to monitor these absorbable IVCFs, nanoparticles (NPs) are added to improve radiolucency. In this study, we incorporated tungsten (W) NPs with absorbable polymers as coating materials for PPDO and tested their in vivo imaging efficacy.

Materials and Methods: WNPs were synthesized by thermal decomposition and were characterized in terms of size, morphology and radiopacity. WNPs were coated by wet-dipping onto PPDO with polyhydroxybutyrate (PHB) only (W-P) or with polymer blends (W-PB) consisting of PHB, polycaprolactone, and polyvinylpyrrolidone. IVCFs containing W-P or W-PB were deployed in pigs and then autologous thrombus was introduced. CT images were taken weekly for 12 weeks.

Results: Synthesized WNPs (16.31 ± 3.73 nm) with polymers were successfully coated onto PPDO IVCFs. Table 1 shows the physicochemical properties of the PPDO with and without WNP coating. Incorporation of W-P and W-PB coating onto PPDO enhanced filter visualization in vitro and in vivo during fluoroscopy-guided deployment in pigs. At the time of deployment, W-PB filter had two-fold higher HU intensity (838.64 ± 44.64 HU) compared to W-P (404.49 ± 52.39 HU). Furthermore, initial in vivo CT monitoring showed 11-fold signal enhancement of W-PB (763.07 ± 330.9 HU) compared to the background (muscle, 69.7 ± 13.00 HU), while W-P was only 8-fold higher (469.80 ± 220.00 HU) than the background (muscle, 57.22 ± 8.00 HU). Maximum HU values showed decreasing CT intensities throughout the 12 weeks for both W-P only and W-PB.

Conclusion: Bioresorbable IVCFs coated with W-P or W-PB can be fully visualized with fluoroscopy and CT for real-time image-guided deployment and monitoring of IVCF in pigs. Further in vitro release and in vivo immunohistological analyses are ongoing to assess the biocompatibility and potential toxicity of the WNP-infused IVCF with the different polymer blends.