Enhancement of fluorescence molecular tomography with structural-prior-based diffuse optical tomography: combating optical background uncertainty

Abstract

The common approach in fluorescence molecular tomography (FMT) assumes homogeneous distributions of the optical properties and normally results in reconstructions of low sensitivity. A natural enhancement is to incorporate diffuse optical tomography (DOT) to FMT. However, the traditional voxel-based DOT has been a severely ill-posed inverse problem and cannot retrieve the optical property distributions accurately. We present a structural-prior-based DOT method to effectively acquire the heterogeneous optical background with the aid of some imperfect structural priors from x-ray computed tomography and/or magnetic resonance imaging anatomical imaging modalities, and quantitatively compare its hard- and soft-prior schemes for achieving an improved recovery of the fluorescence distribution. Numerical simulations are conducted on a region-labeled three-dimensional (3D) digital mouse model to investigate the performance of this method. Physical experiments on a cylindrical phantom are also conducted to assess this methodology. Our simulated and experimental reconstruction results indicate that the structural-prior-based DOT guided FMT approach can significantly improve the sensitivity of FMT reconstruction, as well as its imaging resolution and quantitative accuracy.

Reconstruction of an optical inhomogeneity map improves fluorescence diffuse optical tomography

“…Theses results confirm the importance to incorporate the optical heterogeneities into the forward model involved in FDOT reconstructions [30,31,37,38,62]. They are consistent with those showing that the nBorn method only partially compensate the fluorescence reconstruction errors due to the presence of optical heterogeneities, especially in the presence of scattering inclusions [17,18].…”

“…Therefore, it is highly desirable to recover the optical properties of the heterogeneities from optical measurements, which can be done by performing a diffuse optical tomography (DOT) reconstruction at the excitation wavelength [32][33][34][35][36][37][38]. However, continuous wave (CW) measurements at a single wavelength cannot resolve both absorption and scattering coefficients [39].…”

Recent methodology advances in fluorescence molecular tomography

“…The structure of imaging space prior information can usually be obtained by high-resolution structural imaging modalities such as computed tomography (CT), magnetic resonance imaging (MRI) [91][92][93][94][95][96]. The optical parameters of various organs and tissues can be obtained by other imaging techniques such as diffuse optical tomography (DOT) [97]. The imaging technique that combines imaging modalities to increase imaging prior information is also known as Multi-Modality imaging and is the focus of current medical imaging research [4].…”