Abstract:
A confocal scanning microscope system (10) using cross polarization effects and an enhancement agent (acetic acid) to enhance confocal microscope reflectance images of the nuclei of BCCs (basal cell carcinomas) and SCCs (squamous call carcinomas) in the confocal reflectance images of excised tumor slices. The confocal scanning microscope system having a laser (11) for generating an illumination beam (12), a polygon mirror (18) for scanning the beam to a tissue sample (22) and for receiving a return beam from the tissue sample and detector (28) for detecting the returned beam to form an image. The system further includes a half-waveplate (13) having a rotatable stage (14) and a quarter-wave plate (21) having a rotatable stage (20) disposed in the optical path of the illumination beam and at least a linear polarizer (24) having a rotatable stage (25) disposed in the optical path of the returned beam from the tissue sample.
Abstract:
A confocal microscope is provided including a confocal imaging system having an objective lens, and a device which can be an attachment to the confocal imaging system, or a part thereof. The device has a housing with an interior cavity and two opposite ends, where one end of the housing receives the objective lens, and at the other end of the housing which is attached to, or is a part of, the housing which forms that other end. The chamber has first and second plates presenting two opposing sides of the chamber, where the first plate lies adjacent the tissue to be treated, and the second plate is attached to the housing. The interior cavity of the housing has a window defining a first volume between the window and the objective lens, and a second volume between the window and the chamber. The first volume has an immersion liquid optically matched to the objective lens, and the second volume is approximately evacuated. The confocal imaging system, via the device, focuses light into the tissue and collects returned light from the tissue to produce images representing one or more sections of the tissue. To freeze the tissue, the chamber receives a cryogenic fluid, such as liquid nitrogen, thereby cryosurgically treating the tissue below the chamber which includes the imaged tissue. The chamber has an input port to receive the cryogenic fluid and an output port to vent the cryogenic fluid. The confocal microscope can provide images of the tissue before, during and after cryosurgical treatment.
Abstract:
A cassette for retaining a specimen of surgically exposed tissue from a patient in an orientation that facilitates optical sectioning of the tissue by a confocal microscopic or other optical imaging microscope. The cassette includes a base member having a rigid optically transparent window upon which a tissue specimen is situated, a pliable membrane locatable over a substantial portion of the base member including the window, and an upper member, having an aperture therethrough, which can cover the base member to provide an enclosed cavity between the membrane and the window sealing the tissue specimen therein. With the tissue specimen in the enclosed cavity of the cassette, the edges of the tissue specimen may be positioned planar against the window and retained in that position by bonds formed between the membrane and window at multiple points or locations around the tissue specimen. The specimen retained in the cavity is viewable through the aperture of the upper member and imagible by a confocal microscope, or other optical imaging microscope, through the window of the base member. The base member has an injection port through which fluid may be inserted and removed from the cavity of the cassette in which the tissue specimen is retained. Such fluids can facilitate imaging of the specimen by an optical imaging microscope, or can be used to place the specimen in a preservative for archival purposes. A label with indicia identifying the tissue specimen may be applied to the cassette. The cassette may be part of a confocal imaging system to produce microscopic images of sections of the tissue specimen useful for Mohs surgery.
Abstract:
A hand held microsurgical instrument for applying laser energy to selected locations (sites) in an area under the skin (or other exposed translucent tissue) to provide localized photothermolysis of underlying tissue at these sites, is described. The laser energy is focused into a spot within the tissue. This spot is of sufficiently small size so that the energy density is sufficient to provide surgical or treatment effects within the tissue without damaging the surface tissue. In dermatology, for example, the technique can be used to destroy endothelial cells in blood vessels which are desired to be removed, such spider veins (nevi) in the skin, hair follicles to prevent hair growth therefrom, or other microsurgical procedures. The area is visualized while the laser beam is steered, using a deflection system, in X and Y coordinates. A telecentric optical system, in which a mirror of the deflection system is located, directs the laser light essentially perpendicular to the area to be treated as the beam is scanned over the area. The optical system also focuses illumination light reflected from the area to a sensor matrix of a CCD video camera. The reflected illumination light is imaged essentially parallel to the optical axis in the object space thereby providing a precise, high resolution image corresponding to the area. The laser beam may be tracked as it is deflected over the area to the selected locations by visualization thereof on a display or monitor associated with the video camera. The locations are then apparent to the treating physician who can then effect an increase of the beam power or turn the beam on so as to treat the tissue in the selected locations.
Abstract:
In order to permanently remove hair growing in subcutaneous (below the skin's surface) tissue and to do so permanently, the hair and its root structure is epilated (vaporized) in an ablation cavity of essentially the same size and shape as the volume occupied by the root structure which includes follicle, the follicle bulb and the dermal papilla. Optical energy is used which is of a wavelength and fluence sufficient to cause epilation in the cavity without relying upon selective photothermolysis thereby limiting damage to tissue outside of the hair root structure. To find and restrict the optical energy to the epilation cavity, an optical system, which may be constituted of a single lens, having a numerical aperture of F/5-5.8 is used. The beam is generated by a laser which may be operated in a pulse mode and contained in a hand piece having the optical system at the end thereof. In order to facilitate epilation, a medium such as a cold compress or a freezing agent, may be applied before application of the laser energy in order to cause the root structure and the hair to move to a location generally perpendicular to the surface of the skin. During application of the laser energy, the root structure and the hair, if present, is progressively ablated and vaporized until the bottom of the hair bulb is reached at which time the beam is turned off. Because of the shaping effect of the optical system, the beam is diffused so as to have insufficient fluence to damage the tissue below the bottom of the hair follicle bulb.
Abstract:
A multichannel optical head and data storage system employs an integrated-optical read channel. The read channel may be fabricated on a planar waveguide structure that separates the data signals of the multiple lasers. The read channel includes focus error sensors and track error sensors. The optical head may be used for amplitude recording systems such as phase-change erasable and write-once media, ablation media, dye-polymer media, and OD-ROM systems.
Abstract:
The objective lens of an optical disk drive has a suitable positioning and numerical aperture so that the light beam will be focused into a spot on the optical media of a first optical disk having a cover plate with a first thickness. When a second optical disk is utilized having a cover plate with a second thickness different from the first thickness, a liquid crystal compensator lens is actuated in the optical path between the light source and the objective lens for focusing the light beam into a spot on the optical media of the second optical disk. A correction signal may be applied to the liquid crystal in the compensator lens for altering a refractive index thereof. This substantially eliminates a wavefront aberration in the reflected light beam which would otherwise occur if the beam were focused onto the optical media of the second optical disk solely by use of the objective lens. The lower alignment film of the liquid crystal compensator lens has a cross-section which is approximately sinusoidal in order to complement three waves of aberration (measured from peak-to-valley) in the reflected wavefront.
Abstract:
A multiple beam optical system includes a housing which contains a pair of laser diodes and a pair of optical detectors. The lasers produce overlapping beams of light. The housing includes a beam directing and reflecting member which selectively focuses light from one of the lasers to a corresponding optical detector located in the housing and selectively focuses light from the other laser to its corresponding optical detector located within the housing. The individual power of each of the overlapping laser beams is thereby monitored by the separate detectors.
Abstract:
A cassette for retaining a specimen of surgically exposed tissue from a patient in an orientation that facilitates optical sectioning of the tissue by a confocal microscopic or other optical imaging microscope. The cassette includes a base member having a rigid optically transparent window upon which a tissue specimen is situated, a pliable membrane locatable over a substantial portion of the base member including the window, and an upper member, having an aperture therethrough, which can cover the base member to provide an enclosed cavity between the membrane and the window sealing the tissue specimen therein. The edges of the tissue specimen may be positioned planar against the window and retained in that position by bonds formed between the membrane and window at multiple points or locations around the tissue specimen. The specimen retained in the cavity is imagible a microscope through the window of the base member.
Abstract:
An improved system for confocal imaging within dermal tissue of a patient is provided which minimizes instability in confocal images by reducing the relative motion of the tissue with respect to the confocal imaging optics of the system. The system includes a mechanism for maintaining an area of skin tissue under stress by application of force at the edges of the area, and an imaging head coupled to this mechanism for imaging the stressed skin. The mechanism includes a mechanical structure, such as a platen, brace, or attachment, which both supports the imaging head of the system and applies stress to a limited surface area of the tissue to minimize skin motion during confocal imaging.