Papers Published

1. Puzrin, A. and Skrinjar, O. and Ozan, C. and Sihyun Kim and Mukundan, S., Image guided constitutive modeling of the silicone brain phantom, Proc. SPIE - Int. Soc. Opt. Eng. (USA), vol. 5744 no. 1 (2005), pp. 157 - 64 [12.595689] .
   (last updated on 2007/04/15)

   Abstract:
   The goal of this work is to develop reliable constitutive models of the mechanical behavior of the in-vivo human brain tissue for applications in neurosurgery. We propose to define the mechanical properties of the brain tissue in-vivo, by taking the global MR or CT images of a brain response to ventriculostomy - the relief of the elevated intracranial pressure. 3D image analysis translates these images into displacement fields, which by using inverse analysis allow for the constitutive models of the brain tissue to be developed. We term this approach Image Guided Constitutive Modeling (IGCM). The presented paper demonstrates performance of the IGCM in the controlled environment: on the silicone brain phantoms closely simulating the in-vivo brain geometry, mechanical properties and boundary conditions. The phantom of the left hemisphere of human brain was cast using silicon gel. An inflatable rubber membrane was placed inside the phantom to model the lateral ventricle. The experiments were carried out in a specially designed setup in a CT scanner with submillimeter isotropic voxels. The non-communicative hydrocephalus and ventriculostomy were simulated by consequently inflating and deflating the internal rubber membrane. The obtained images were analyzed to derive displacement fields, meshed, and incorporated into ABAQUS. The subsequent Inverse Finite Element Analysis (based on Levenberg-Marquardt algorithm) allowed for optimization of the parameters of the Mooney-Rivlin non-linear elastic model for the phantom material. The calculated mechanical properties were consistent with those obtained from the element tests, providing justification for the future application of the IGCM to in-vivo brain tissue

   Keywords:
   biomechanics;biomedical MRI;boundary-value problems;brain;computerised tomography;finite element analysis;image registration;inverse problems;medical image processing;neurophysiology;optimisation;phantoms;physiological models;silicones;surgery;