| Author | Li Dong, Philip Wijesinghe, James T. Dantuono, David D. Sampson, Peter R.T. Munro, Brendan F. Kennedy, and Assad A. Oberai |
|---|---|
| Title | Quantitative Optical Coherence Elastography as an Inverse Elasticity Problem |
| Year | 2016 |
| Journal | IEEE Journal of Selected Topics in Quantum Electronics |
| Volume | to appear |
| Abstract | Quantitative elasticity imaging retrieves maps of elastic moduli from tissue. Quantitative imaging is superior to qualitative imaging in producing images which are operator and system independent, and enable objective, longitudinal and multi-site diagnoses. Quantitative elasticity imaging has been demonstrated in optical elastography by assuming largely homogeneous samples. We present a more general approach to quantitative elasticity imaging using quasi-static compression optical coherence elastography, based upon the iterative solution of the inverse elasticity problem. We present a solution for the case of linear elastic, isotropic, incompressible solids, however, this method can be employed for arbitrarily complex mechanical models. The inverse elasticity problem is solved by finding the spatial distribution of shear modulus which results in close agreement between predicted and measured displacements. Key to the solution of the inverse elasticity problem is the use of the adjoint equations that allow the very efficient evaluation of the gradient of the objective function to be minimized with respect to the unknown values of shear modulus within the sample. We apply this method of shear modulus retrieval to one phantom and to one tissue sample. |