Abstract: Apparatus and methods for tissue excision. In certain aspects, the apparatus and methods include an annular converging laser beam. The annular converging laser beam can be directed to a surface of a tissue and displace a portion of the tissue in a single or multiple laser pulses. In particular aspects, the dosimetry of the laser beam (e.g. the beam shape, pulse energy and pulse duration) can be controlled to eject the portion of the tissue in a manner to reduce damage to the displaced tissue and the surrounding tissue.

Abstract: A fiber-optic probe for multi-modal characterization of a tissue. The fiber optic probe may comprise a first group of fibers associated with a first modality of light. The first group of fibers may comprise a first light delivery fiber and a first light collection fiber. The fiber optic probe may also comprise a second group of fibers associated with at least a second modality of light, the second group of fibers comprising a second light delivery fiber and a second light collection fiber; The fiber optic probe may also comprise a longpass filter positioned distal to the first group of fibers and a lens positioned distal to the filter. The fiber optic probe may also comprise. The fiber optic probe may include the second group of fibers bypassing the filter. The second group of fibers may bypass the filter.

Abstract: Systems comprising an optical fiber switch connected to a light source and an optical fiber probe, the optical fiber probe comprising a first optical fiber connected to the optical fiber switch and a second optical fiber connected to a spectrophotometer. Methods for determining one or more tissue parameters comprising: emitting light from a first optical fiber into a tissue; collecting the light reemitted from the tissue with a second optical fiber; generating a spectra of the light reemitted from the tissue with a spectrophotometer; and utilizing a look-up table based algorithm to determine one or more tissue parameters, wherein the lookup-table based algorithm comprises the steps of: generating a look-up table by measuring the functional form of a reflectance measured by the spectrophotometer using one or more calibration standards with known optical properties; and implementing an iterative fitting routine based on the lookup-table.

Abstract: An imaging apparatus comprises a first optical fiber configured to deliver a source beam of light generated by a light source and a polarizing beam splitter configured to polarize the source beam of light and direct diffusely reflected light toward a collection fiber optically coupled to an optical detector. The imaging apparatus also comprises a mirror configured to reflect the polarized beam of light onto the lens and direct reflected light away from a lens. The lens is configured to focus the polarized source beam of light onto an area of sample material and focus diffusely reflected light from the sample material into a reflection beam. The imaging apparatus also comprises a plano-convex curvature matching window disposed at a focal plane of the lens, wherein a convex surface of the curvature matching window is substantially matched to the focal plane curvature of the imaging lens.

Abstract: Systems comprising an optical fiber switch connected to a light source and an optical fiber probe, the optical fiber probe comprising a first optical fiber connected to the optical fiber switch and a second optical fiber connected to a spectrophotometer. Methods for determining one or more tissue parameters comprising: emitting light from a first optical fiber into a tissue; collecting the light reemitted from the tissue with a second optical fiber; generating a spectra of the light reemitted from the tissue with a spectrophotometer; and utilizing a look-up table based algorithm to determine one or more tissue parameters, wherein the lookup-table based algorithm comprises the steps of: generating a look-up table by measuring the functional form of a reflectance measured by the spectrophotometer using one or more calibration standards with known optical properties; and implementing an iterative fitting routine based on the lookup-table.

Abstract: Devices and methods are provided for image identification of contrast agents comprising nanopartiles. The imaging devices and methods may also be configured to identify target tissues from surrounding tissues such as disease conditions (e.g. cancer tumors) through narrow-band imaging of tissue. Contrast agents such as near-infrared absorbing nanoparticles may be introduced to an organism to distinguish target cells, tissues, or structures from normal tissue. The contrast agent is allowed to preferentially accumulate in the target cells, tissues or structures. As the contrast agents are adapted to preferentially absorb one or more wavelengths of light, the reflection of one wavelength or band of wavelengths by the contrast agents is compared to a separate wavelength or band of wavelengths to identify the target cells, tissues, or structures. In this way, the comparisons identify the presence of the preferential accumulation of the contrast agent in the target cells, tissues or structures.

Abstract: A non-invasive method to measure metal nanoparticle concentrations in bulk tissue is provided. A simple diagnostic assay to detect nanoparticle concentration in bulk tissue has been developed herein. One such provided method comprises: applying diffuse optical spectroscopy to a tissue having nanoparticles disposed therein; and applying an inverse algorithm to the light reflected from the nanoparticles. Another such method comprises: exposing tissue that comprises nanoparticles to a light source; collecting light from the tissue using an optical fiber probe; and measuring the concentration of nanoparticles in the tissue. A system is provided comprising: a tissue comprising nanoparticles; a light source arranged to illuminate a portion of the tissue; an optical fiber probe to collect light reflected from the tissue; and a spectrometer to measure the light reflected from the nanoparticles and operably connected to a computer having one or more processors and a memory.