title: Time-domain reconstruction for thermoacoustic tomography in a spherical geometry
abstract: Reconstruction-based microwave-induced thermoacoustic tomography in a spherical configuration is presented. Thermoacoustic waves from biological tissue samples excited by microwave pulses are measured by a wide-band unfocused ultrasonic transducer, which is set on a spherical surface enclosing the sample. Sufficient data are acquired from different directions to reconstruct the microwave absorption distribution. An exact reconstruction solution is derived and approximated to a modified backprojection algorithm. Experiments demonstrate that the reconstructed images agree well with the original samples. The spatial resolution of the system reaches 0.5 mm
keyphrases: time-domain reconstruction thermoacoustic tomography spherical geometry biological tissue samples wide-band unfocused ultrasonic transducer exact reconstruction solution modified backprojection algorithm reconstructed images 0.5 mm medical diagnostic imaging spherical surface enclosing sample system spatial resolution