Two-photon fluorescence and second-harmonic generation imaging of collagen in human tissue based on multiphoton microscopy.

Multiphoton microscopic imaging of collagen plays an important role in noninvasive diagnoses of human tissue. In this study, two-photon fluorescence and second-harmonic generation (SHG) imaging of collagen in human skin dermis and submucosa of colon and stomach tissues were investigated based on multiphoton microscopy (MPM). Our results show that multiphoton microscopic image of collagen bundles exhibits apparently different pattern in human tissues.

Characteristics of scar margin dynamic with time based on multiphoton microscopy.

Scar margins dynamic with time were quantitatively characterized using multiphoton microscopy (MPM). 2D large-area and 3D focused images of elastin and collagen at scar margins were obtained to extract quantitative parameters. An obvious boundary was observed at the scar margin, showing altered morphological patterns of elastin and collagen on both sides.

Power calculation of wavelength tunable Yb3+:LSO laser.

A theoretical model is presented describing continuous-wave operation about wavelength tunable Yb(3+):LSO (Yb(3+):Lu(2)SiO(5)) laser. In LSO host, Yb(3+) ion occupies two different Lu(3+) sites and the spectrum exhibits the inhomogeneously broadened property. Working as a computable model, it takes into account the pump absorption saturation, the re-absorption of laser, and the full spectral information of the laser transition.

Multiphoton microscopic imaging of normal human rectum tissue.

In this paper, multiphoton microscopy (MPM), based on two-photon excited fluorescence and second harmonic generation signals, was used to image microstructures of human rectal mucosa and submucosa. The morphology and distribution of the main components in mucosa layer, goblet cells, intestinal glands, and a little collagen fibers have been clearly monitored, and the content and distribution of collagen, elastic fibers, and blood vessels in submucosa layer have also been distinctly obtained. The variation of these components is very relevant to the pathology in gastrointestinal system, especially early rectal cancer.

Stromal optical properties: differentiating normal and cancerous stroma.

This work reports on the measurement of optical properties from nine normal and cancerous human esophageal stroma pairs using reflectance-based confocal microscopy. It was found that the scattering coefficient of cancerous stroma is significantly lower than that of normal stroma. The results suggest that the decreased scattering in cancerous stroma may provide a possible indicator for differentiating normal and cancerous stroma.

[Spectral characteristics of normal breast samples in the 350-850 nm wavelength range].

Spectral characteristics of normal female breast samples in the 350-850 nm wavelength range were measured using a UV/Vis/NIR spectrophotometer system with integrating sphere attachment for measuring the diffuse reflectance and transmittance. The optical properties of normal breast tissue in vitro were obtained by the inverse adding doubling method. And then the optical penetration depths in this spectral range were analyzed based on the principle of tissue optics.

Multiphoton laser scanning microscopy of localized scleroderma.

Background/purpose: A real-time, non-invasive method will confer a benefit for the diagnosis and treatment of localized scleroderma (LS) in the clinic. The aim of this work was to demonstrate the potential of multiphoton laser scanning microscopy (MPLSM) for diagnosing LS and monitoring the treatment response in vivo.

Methods: Three sclerodermatous skin specimens and two normal skin specimens were investigated using MPLSM based on two-photon excitation fluorescence (TPEF) and second harmonic generation (SHG).

Quantified characterization of human cutaneous normal scar using multiphoton microscopy.

The morphological alterations of human cutaneous normal scar were quantitatively analyzed using multiphoton microscopy (MPM) based on two-photon excited fluorescence and second harmonic generation. High-contrast, high-resolution images of normal scar and uninjured skin were obtained for comparison. In addition, some quantitative parameters have been extracted to quantitatively discriminate between normal scar and uninjured skin.

Detecting early breast tumour by finite element thermal analysis.

Thermography has been proved to be an effective technique for indicating breast disease abnormalities or risks. However, the abnormalities might not express clearly due to various factors, such as when a small tumour is located in a deep region, or environmental influences that make breast disease difficult to find. This study aims to solve these problems for early detection of breast tumour.

Nonlinear optical microscopy of the bronchus.

Because of frequent exposure to carcinogens, the bronchus is prone to early pathologic alterations. The assessment of these early changes is of key significance in physiological studies and disease diagnosis of the bronchus. We utilize nonlinear optical microscopy (NLOM) to image mouse bronchial tissue based on intrinsic nonlinear optical contrast.

Differences in optical transport properties between human meridian and non-meridian.

This study is to present a new scheme for the detection of human meridian system non-invasively. The optical transport properties along the pericardium meridian and a non-meridian path about 1 cm away from the meridian were measured non- invasively on 20 healthy people in vivo. 633 nm, 658 nm and 785 nm red lasers were used for irradiation, and the diffuse light emittances at different points on meridian and non-meridian directions were collected respectively and compared.

Appearance of human meridian-like structure and acupoints and its time correlation by infrared thermal imaging.

The meridians and acupoints of human bodies at natural condition are investigated among 30 healthy volunteers by infrared thermal imaging technique. The results give clear evidence of the existence of infrared radiant tracks along human meridian courses. The time dependent evolution of the infrared radiant track is observed for the first time.

[Fluorescence spectroscopy and imaging for optical biopsy].

In the past few years extensive attention has turned toward optical biopsy, because of its ability to perform noninvasive, real time and accurate diagnosis of tissue pathologies, especially precancer. Fluorescence spectroscopy is one of a series of techniques widely developed for optical biopsy, and can be generally divided into two categories: fluorescence spectroscopy and imaging. This paper reviews the applications of autofluorescence and exogenous fluorescence to optical biopsy, and the principle and advantages as well as the clinic applications of various steady-state and time-resolved fluorescence spectroscopy and imaging techniques.

Autofluorescence excitation-emission matrices for diagnosis of colonic cancer.

Aim: To investigate the autofluorescence spectroscopic differences in normal and adenomatous colonic tissues and to determine the optimal excitation wavelengths for subsequent study and clinical application.

Methods: Normal and adenomatous colonic tissues were obtained from patients during surgery. A FL/FS920 combined TCSPC spectrofluorimeter and a lifetime spectrometer system were used for fluorescence measurement.