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Photo-acoustic tomography (PAT)
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Thermo-acoustic tomography (TAT)
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Mueller
optical-coherence tomography (M-OCT)
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Ultrasound-modulated (acousto-) optical tomography (UOT)
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Oblique-incidence reflectometry (OIR) and spectroscopy
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Photon
transport in biological tissues
We develop novel biophotonic tomography for
early-cancer detection and functional imaging using non-ionizing
electromagnetic and ultrasonic waves. Unlike ionizing x-ray radiation,
non-ionizing electromagnetic waves, such as optical and radio
waves, pose no health hazard and, at the same time, reveal new contrast
mechanisms. For example, our spectroscopic oblique-incidence
reflectometry can detect skin cancers accurately based on functional
hemoglobin parameters and cell nuclear size. Unfortunately,
electromagnetic waves in the non-ionizing spectral region do not
penetrate biological tissue in straight paths as x-rays do.
Consequently, high-resolution tomography based on non-ionizing
electromagnetic waves alone, as demonstrated by confocal microscopy and
two-photon microscopy as well as optical coherence tomography, is
limited to superficial imaging within about one optical transport mean
free path (~1 mm) of the surface of biological tissue. Ultrasonic
imaging, on the contrary, provides good image resolution but has strong
speckle artifacts as well as poor contrast in early-stage tumors.
We have developed ultrasound-mediated imaging modalities by
combining electromagnetic and ultrasonic waves synergistically to
overcome the above problems. The hybrid modalities yield
speckle-free images with high electromagnetic contrast at high
ultrasonic resolution in relatively large volumes of biological
tissue. Please visit the Research page for the specific technologies
that we develop. |
