Estimation and Statistical Bounds for Three-Dimensional Polar Shapes in Diffuse Optical Tomography

Abstract--Voxel-based reconstructions in diffuse optical tomography (DOT) using a quadratic regularization functional tend to produce very smooth images due to the attenuation of high spatial frequencies. This then causes difficulty in estimating the spatial extent and contrast of anomalous regions such as tumors. Given an assumption that the target image is piecewise constant, we can employ a parametric model to estimate the boundaries and contrast of an inhomogeneity directly. In this paper, we describe a method to directly reconstruct such a shape boundary from diffuse optical measurements. We parameterized the object boundary using a spherical harmonic basis, and derived a method to compute sensitivities of measurements with respect to shape parameters. We introduced a centroid constraint to ensure uniqueness of the combined shape/center parameter estimate, and a projected Newton method was utilized to optimize the object center position and shape parameters simultaneously. Using t...

• Type: Journal
• Year: 2008
• Where: TMI
• Authors: Gregory Boverman, Eric L. Miller, Dana H. Brooks, David Isaacson, Qianqian Fang, David A. Boas
• Keywords: Measurement Noise, Measurements, Spherical Harmonic, TMI 2008