Improving mesoscopic fluorescence molecular tomography via preconditioning and regularization


YANG F. , Yao R., Ozturk M., Faulkner D., QU Q., Intes X.

BIOMEDICAL OPTICS EXPRESS, vol.9, no.6, pp.2765-2778, 2018 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 9 Issue: 6
  • Publication Date: 2018
  • Doi Number: 10.1364/boe.9.002765
  • Title of Journal : BIOMEDICAL OPTICS EXPRESS
  • Page Numbers: pp.2765-2778

Abstract

Mesoscopic fluorescence molecular tomography (MFMT) is a novel imaging technique capable of obtaining 3-D distribution of molecular probes inside biological tissues at depths of a few millimeters with a resolution up to similar to 100 mu m. However, the ill-conditioned nature of the MFMT inverse problem severely deteriorates its reconstruction performances. Furthermore, dense spatial sampling and fine discretization of the imaging volume required for high resolution reconstructions make the sensitivity matrix (Jacobian) highly correlated, which prevents even advanced algorithms from achieving optimal solutions. In this work, we propose two computational methods to respectively increase the incoherence of the sensitivity matrix and improve the convergence rate of the inverse solver. We first apply a compressed sensing (CS) based preconditioner on either the whole sensitivity matrix or sub sensitivity matrices to reduce the coherence between columns of the sensitivity matrix. Then we employed a regularization method based on the weight iterative improvement method (WIIM) to mitigate the ill-condition of the sensitivity matrix and to drive the iterative optimization process towards convergence at a faster rate. We performed numerical simulations and phantom experiments to validate the effectiveness of the proposed strategies. In both in silico and in vitro cases, we were able to improve the quality of MFMT reconstructions significantly. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement