Filtered backprojection for thermoacoustic computed tomography in spherical geometry
نویسندگان
چکیده
Thermoacoustic computed tomography (TCT) is a novel imaging technique for non-destructive evaluation and medical imaging. It uses electromagnetic energy as input and the induced thermoacoustic pressure eld as measurement output. The determination of the unknown energy deposition function is based on the integral geometric problem of reconstructing a function from its integrals over certain spheres. We apply the method of approximate inverse to derive ltered backprojection type reconstruction algorithms in spherical scanning geometry. Numerical results are presented and show the validity of the resulting algorithms. Copyright ? 2005 John Wiley & Sons, Ltd.
منابع مشابه
Microwave-induced thermoacoustic scanning CT for high-contrast and noninvasive breast cancer imaging.
A fast thermoacoustic computed tomography system with a multielement linear transducer array was developed to image biological tissues with circular scanning. The spatial resolution of the imaging system and the spectra of the thermoacoustic signals were analyzed. A modified integration backprojection algorithm using velocity potential was employed to recover the direct energy deposition distri...
متن کاملThermoacoustic Tomography - Implementation of Exact Backprojection Formulas
The problem of image reconstruction in thermoacoustic tomography requires inversion of a generalized Radon transform, which integrates the unknown function over circles in 2D or spheres in 3D. The paper investigates implementation of the recently discovered backprojection type inversion formulas for the case of spherical acquisition in 3D. A numerical simulation of the data acquisition with sub...
متن کاملA Family of Inversion Formulas in Thermoacoustic Tomography
We present a family of closed form inversion formulas in thermoacoustic tomography in the case of a constant sound speed. The formulas are presented in both time-domain and frequency-domain versions. As special cases, they imply most of the previously known filtered backprojection type formulas.
متن کاملPulsed-microwave-induced thermoacoustic tomography: filtered backprojection in a circular measurement configuration.
Our study on pulsed-microwave-induced thermoacoustic tomography in biological tissues is presented. A filtered backprojection algorithm based on rigorous theory is used to reconstruct the cross-sectional image from a thermoacoustic measurement in a circular configuration that encloses the sample under study. Specific details describing the measurement of thermoacoustic waves and the implementat...
متن کاملThermoacoustic tomography with detectors on an open curve
Practical applications of thermoacoustic tomography require numerical inversion of the spherical mean Radon transform with the centers of integration spheres occupying an open surface. A solution of this problem is needed (both in 2D and in 3D) because frequently the region of interest cannot be completely surrounded by the detectors, as happens, for example, in breast imaging. We present an ef...
متن کامل