title: Subject-specific non-linear biomechanical model of needle insertion into brain.
abstract: The previous models for predicting the forces acting on a needle during insertion into very soft organs (such as, e.g. brain) relied on oversimplifying assumptions of linear elasticity and specific experimentally derived functions for determining needle-tissue interactions. In this contribution, we propose a more general approach in which the needle forces are determined directly from the equations of continuum mechanics using fully non-linear finite element procedures that account for large deformations (geometric non-linearity) and non-linear stress-strain relationship (material non-linearity) of soft tissues. We applied these procedures to model needle insertion into a swine brain using the constitutive properties determined from the experiments on tissue samples obtained from the same brain (i.e. the subject-specific constitutive properties were used). We focused on the insertion phase preceding puncture of the brain meninges and obtained a very accurate prediction of the needle force. This demonstrates the utility of non-linear finite element procedures in patient-specific modelling of needle insertion into soft organs such as, e.g. brain.
authors.affiliation: Intelligent Systems for Medicine Laboratory, School of Mechanical Engineering, The University of Western Australia, Perth-Crawley, Western Australia, Australia. adwit@mech.uwa.edu.au
authors.forename: A
authors.initials: A
authors.lastname: Wittek
authors.forename: T
authors.initials: T
authors.lastname: Dutta-Roy
authors.forename: Z
authors.initials: Z
authors.lastname: Taylor
authors.forename: A
authors.initials: A
authors.lastname: Horton
authors.forename: T
authors.initials: T
authors.lastname: Washio
authors.forename: K
authors.initials: K
authors.lastname: Chinzei
authors.forename: K
authors.initials: K
authors.lastname: Miller
mesh_terms: D001696:Biomechanical Phenomena / Q000379:methods*; D001921:Brain / Q000502:physiology*; D003198:Computer Simulation; D004548:Elasticity; D006244:Hardness; D006801:Humans; D008954:Models, Biological; D009339:Needles; D019919:Prosthesis Implantation / Q000379:methods*; D011677:Punctures / Q000295:instrumentation* / Q000379:methods*; D013314:Stress, Mechanical; D014783:Viscosity