Methods of acoustical tomography of the third-order nonlinear parameter for the purpose of medical diagnostics are considered. Tomographic schemes based on noncollinear interaction of three coded waves, allowing to obtain numerical values of nonlinear parameter, are preferred.
43.60.Pt Signal processing techniques for acoustic inverse problems
43.60.Rw Remote sensing methods, acoustic tomography
43.60.Kx Matched field processing
Department of acoustics, Faculty of Physics, Lomonosov Moscow State University. Moscow 119991, Russia.