Evaluating the interaction of a tracheobronchial stent in an ovine in-vivo model

Donnacha J. McGrath, Anja Lena Thiebes, Christian G. Cornelissen, Barry O'Brien, Stefan Jockenhoevel, Mark Bruzzi, Peter E. McHugh*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

5 Citations (Web of Science)

Abstract

Tracheobronchial stents are used to restore patency to stenosed airways. However, these devices are associated with many complications such as stent migration, granulation tissue formation, mucous plugging and stent strut fracture. Of these, granulation tissue formation is the complication that most frequently requires costly secondary interventions. In this study a biomechanical lung modelling framework recently developed by the authors to capture the lung in-vivo stress state under physiological loading is employed in conjunction with ovine pre-clinical stenting results and device experimental data to evaluate the effect of stent interaction on granulation tissue formation. Stenting is simulated using a validated model of a prototype covered laser-cut tracheobronchial stent in a semi-specific biomechanical lung model, and physiological loading is performed. Two computational methods are then used to predict possible granulation tissue formation: the standard method which utilises the increase in maximum principal stress change, and a newly proposed method which compares the change in contact pressure over a respiratory cycle. These computational predictions of granulation tissue formation are then compared to pre-clinical stenting observations after a 6-week implantation period. Experimental results of the pre-clinical stent implantation showed signs of granulation tissue formation both proximally and distally, with a greater proximal reaction. The standard method failed to show a correlation with the experimental results. However, the contact change method showed an apparent correlation with granulation tissue formation. These results suggest that this new method could be used as a tool to improve future device designs.
Original languageEnglish
Pages (from-to)499-516
Number of pages18
JournalBiomechanics and modeling in mechanobiology
Volume17
Issue number2
DOIs
Publication statusPublished - 1 Apr 2018

Keywords

  • Biomechanical
  • Lung
  • Tracheobronchial
  • Nitinol
  • Stenting
  • Granulation
  • Finite element method
  • DEFORMABLE IMAGE REGISTRATION
  • METALLIC AIRWAY STENTS
  • SELF-EXPANDING STENT
  • LUNG MOTION
  • INTERVENTIONAL BRONCHOSCOPY
  • RADIAL FORCE
  • SIMULATION
  • ACCURACY
  • OUTCOMES
  • DESIGN

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