Dental optical coherence tomography.

This review paper describes the applications of dental optical coherence tomography (OCT) in oral tissue images, caries, periodontal disease and oral cancer. The background of OCT, including basic theory, system setup, light sources, spatial resolution and system limitations, is provided. The comparisons between OCT and other clinical oral diagnostic methods are also discussed.

Characterization of tooth structure and the dentin-enamel zone based on the Stokes-Mueller calculation.

This is the first study of dentin-enamel zone (DEZ) identification with tooth structure characterization based on the optical Stokes-Mueller measurement. Stokes vectors of a cross-sectional tooth slice were measured using various polarization inputs. The direction of the DEZ is different in enamel and dentin structures; therefore, the Stokes profiles can specifically characterize the structures based on the DEZ.

Brain structure and spatial sensitivity profile assessing by near-infrared spectroscopy modeling based on 3D MRI data.

The goal of this study is to prove that the light propagation in the head by used the 3-D optical model from in vivo MRI data set can also provide significant characteristics on the spatial sensitivity of cerebral cortex folding geometry based on Monte Carlo simulation. Thus, we proposed a MRI based approach for 3-D brain modeling of near-infrared spectroscopy (NIRS). In the results, the spatial sensitivity profile of the cerebral cortex folding geometry and the arrangement of source-detector separation have being necessarily considered for applications of functional NIRS.

Patient-oriented simulation based on Monte Carlo algorithm by using MRI data.

Background: Although Monte Carlo simulations of light propagation in full segmented three-dimensional MRI based anatomical models of the human head have been reported in many articles. To our knowledge, there is no patient-oriented simulation for individualized calibration with NIRS measurement. Thus, we offer an approach for brain modeling based on image segmentation process with in vivo MRI T1 three-dimensional image to investigate the individualized calibration for NIRS measurement with Monte Carlo simulation.

Diffuser-aided diffuse optical imaging for breast tumor: a feasibility study based on time-resolved three-dimensional Monte Carlo modeling.

This study proposed diffuser-aided diffuse optical imaging (DADOI) as a new approach to improve the performance of the conventional diffuse optical tomography (DOT) approach for breast imaging. The 3-D breast model for Monte Carlo simulation is remodeled from clinical MRI image. The modified Beer-Lambert's law is adopted with the DADOI approach to substitute the complex algorithms of inverse problem for mapping of spatial distribution, and the depth information is obtained based on the time-of-flight estimation.

Aorta fluorescence imaging by using confocal microscopy.

The activated leukocyte attacked the vascular endothelium and the associated increase in VEcadherin number was observed in experiments. The confocal microscopic system with a prism-based wavelength filter was used for multiwavelength fluorescence measurement. Multiwavelength fluorescence imaging based on the VEcadherin within the aorta segment of a rat was achieved.

The utility of far-infrared illumination in oxygenation dynamics as measured with near-infrared spectroscopy.

Near-infrared spectroscopy (NIRS) is a noninvasive method for measuring the oxygenation in muscle and other tissues in vivo. For quantitative NIRS measurement of oxygenation dynamics, the vessel-occlusion test was usually applied as physiological intervention. There are several drawbacks of the vessel-occlusion method that include skin contact, uncomfortable and microcirculation block of patients.

Subgingival calculus imaging based on swept-source optical coherence tomography.

We characterized and imaged dental calculus using swept-source optical coherence tomography (SS-OCT). The refractive indices of enamel, dentin, cementum, and calculus were measured as 1.625 ± 0.

Diffuse optical multipatch technique for tissue oxygenation monitoring: clinical study in intensive care unit.

Diffuse optical multipatch technique is used to assess spatial variations in absorption and scattering in biological tissue, by monitoring changes in the concentration of oxyhemoglobin and deoxyhemoglobin. In our preliminary study, the temporal tracings of tissue oxygenation are measured using diffuse optical multipatch measurement and a venous occlusion test, employing normal subjects and ICU patients suffering from sepsis and heart failure. In experiments, obvious differences in tissue oxygenation signals were observed among all three groups.