Parallel, Rapid Diffuse Optical Tomography of Breast

Abstract

Abstract : During the last year we have experimentally and computationally investigated rapid acquisition and analysis of informationally dense diffuse optical data sets in the parallel plate compressed breast geometry. We have developed and tested a 3-dimensional image reconstruction algorithm for the diffusive wave inverse problem that runs on a parallel computer cluster. This code uses a finite difference method in the forward calculation, a novel Integro-Differential equation, previously developed by this group, in the reconstruction. There has been a significant improvement in our instrumentation and measurement capabilities. A hybrid RF/CW diffuse optical tomography (DOT) system measures limited number of frequency-domain reemission data and significantly larger continuous wave transmission data by a lens coupled CCD simultaneously. The wavelength of the light source is optically switched from 690, 750, 786 and 830 nm and then its position is switched among 45 different positions on the compression plate. The instrument and reconstruction algorithm performance have been tested using small silicone tissue phantoms as a tumor of various size and optical properties suspended into the liquid tissue phantom. The study of the effect of boundary between the matching fluid and breast has been initiated by building and taking measurements from tissue phantoms with breast shape, embedded with small objects with higher absorption or scattering.