Diffuse optical tomography with a priori anatomical information.
Diffuse optical tomography (DOT) poses a typical ill-posed inverse problem with a limited number of measurements and inherently low spatial resolution. In this paper, we propose a hierarchical Bayesian approach to improve spatial resolution and quantitative accuracy by using a priori information provided by a secondary high resolution anatomical imaging modality, such as magnetic resonance (MR) or x-ray. In such a dual imaging approach, while the correlation between optical and anatomical images may be high, it is not perfect. For example, a tumour may be present in the optical image, but may not be discernable in the anatomical image. The proposed hierarchical Bayesian approach allows incorporation of partial a priori knowledge about the noise and unknown optical image models, thereby capturing the function-anatomy correlation effectively. We present a computationally efficient iterative algorithm to simultaneously estimate the optical image and the unknown a priori model parameters. Extensive numerical simulations demonstrate that the proposed method avoids undesirable bias towards anatomical prior information and leads to significantly improved spatial resolution and quantitative accuracy.
Guven
Murat
M
Electrical, Computer, and Systems Engineering Department, Rensselaer Polytechnic Institute, Troy, NY, USA.
Yazici
Birsen
B
Intes
Xavier
X
Chance
Britton
B
D000715:Anatomy; D001499:Bayes Theorem; D055590:Electromagnetic Phenomena; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D014054:Tomography / Q000379:methods*