Abstract: A vibro-acoustography imaging system that generates a map of the mechanical response of a target to an acoustic radiation force, usually in low kHz range by a confocal geometry. The system generates two focused sinusoidal beams to produce a stress field at the beat frequency, which is a function of vibration and acoustic emissions field in terms of mechanical properties. A highly sensitive hydrophone is then used for detection of the acoustic emissions field, the amplitude of which may be correlated to the mechanical properties of the target tissue.

Abstract: Systems, methods and apparatuses for performing wound analysis using THz imaging are provided. Due to the large complex component of water's dielectric constant in the THz regime, and the relative frequency invariance of non-aqueous tissue constituents, this modality is highly sensitive to the water content of tissue. It has been found that using THz imaging turns the presence of edema into a contrast mechanism, and allows for the use of the spatial distributions of edema to assess wound status immediately. Apparatus and methods enable earlier diagnosis of wound status which could result in accelerated treatment and shorter overall hospital stays.

Abstract: Methods and apparatus for corneal imaging and sensing are provided. Apparatus capable of utilizing single or multiple frequency emissions at terahertz (THz) wavelengths to create reflectivity maps of the cornea in either a contact or non-contact modes are also provided. Methods of obtaining data from THz imaging and sensing apparatus about the corneal tissue-aqueous humor system, including information about the corneal tissue water content (CTWC) and/or the central corneal thickness (CCT) are likewise provided. Methodologies may use multiple transfer functions (frequencies) in obtaining simultaneous data about CTWC and CCT. Methods using frequency sweeping to allow for determination of CTWC and CCT may also be utilized. Methods may also be used to assess CTWC using multiple bandwidths at the same frequency, or multiple frequencies at the same bandwidth. Methods may use data from CTWC measurements to aid in the diagnosis of various corneal and brain disorders.

Abstract: Methods and systems for single beam scanning capable of imaging the surface of a spherical body of arbitrary radius of curvature are provided. The spherical imaging methods and systems utilize one or more off-axis parabolic (OAP) mirror to perform a geometrical transformation of the spherical surface to a flat rectilinear imaging coordinate grid such that the single scanning beam maintains a normal incidence across the curved field of view of the spherical body. The imaging methods and systems project the spherical surface to a Cartesian plane and then the remapped surface is rapidly imaged by raster-scanning an illumination beam in the rectangular coordinate such that the OAP mirror produces a rectilinear image of the target. The imaging of the spherical surface is accomplished while maintaining the target, illumination source, and detector in a stationary position. The imaging systems and methods may utilize a single source and a single detector, and may incorporate a THz illumination source.

Abstract: A vibro-acoustography imaging system that that generates a map of the mechanical response of a target to an acoustic radiation force, usually in low kHz range by a confocal geometry. The system generates two focused sinusoidal beams to produce a stress field at the beat frequency, which is a function of vibration and acoustic emissions field in terms of mechanical properties. A highly sensitive hydrophone is then used for detection of the acoustic emissions field, the amplitude of which may be correlated to the mechanical properties of the target tissue.

Abstract: Methods and apparatus for corneal imaging and sensing are provided. Apparatus capable of utilizing single or multiple frequency emissions at terahertz (THz) wavelengths to create reflectivity maps of the cornea in either a contact or non-contact modes are also provided. Methods of obtaining data from THz imaging and sensing apparatus about the corneal tissue-aqueous humor system, including information about the corneal tissue water content (CTWC) and/or the central corneal thickness (CCT) are likewise provided. Methodologies may use multiple transfer functions (frequencies) in obtaining simultaneous data about CTWC and CCT. Methods using frequency sweeping to allow for determination of CTWC and CCT may also be utilized. Methods may also be used to assess CTWC using multiple bandwidths at the same frequency, or multiple frequencies at the same bandwidth. Methods may use data from CTWC measurements to aid in the diagnosis of various corneal and brain disorders.

Abstract: Systems, methods and apparatuses for performing wound analysis using THz imaging are provided. Due to the large complex component of water's dielectric constant in the THz regime, and the relative frequency invariance of non-aqueous tissue constituents, this modality is highly sensitive to the water content of tissue. It has been found that using THz imaging turns the presence of edema into a contrast mechanism, and allows for the use of the spatial distributions of edema to assess wound status immediately. Apparatus and methods enable earlier diagnosis of wound status which could result in accelerated treatment and shorter overall hospital stays.

Abstract: Systems and methods for biocompatible tissue characterization using Raman imaging are provided. The systems and methods utilize Raman systems tuned to monitor spectral wavelengths characteristic of target types of tissue to monitor constituents of that tissue in biological systems and samples. The Raman systems may be tuned to monitor the Raman signature for the formation of the chemical bonds that join phosphorous and oxygen (PO) atoms, such that the formation of hydroxyapatite may be monitored and used to determine the presence of bone formation in a sample, such as, for example, biological tissue.

Abstract: A time-resolved fluorescence imaging (TRFI) system that images a target medium without lifetime fitting. Instead of extracting the lifetime precisely, the system images the fluorophore distribution to allow for a simple and accurate method to obtain the fluorescence image without lifetime-extraction for time-resolved fluorescence imaging. An illumination source circuit for TRFI is also disclosed that shapes the excitation pulse. In one embodiment, the illumination source comprises an LED and stub line configured for generating a linear decay profile.

Abstract: Methods and systems for single beam scanning capable of imaging the surface of a spherical body of arbitrary radius of curvature are provided. The spherical imaging methods and systems utilize one or more off-axis parabolic (OAP) mirror to perform a geometrical transformation of the spherical surface to a flat rectilinear imaging coordinate grid such that the single scanning beam maintains a normal incidence across the curved field of view of the spherical body. The imaging methods and systems project the spherical surface to a Cartesian plane and then the remapped surface is rapidly imaged by raster-scanning an illumination beam in the rectangular coordinate such that the OAP mirror produces a rectilinear image of the target. The imaging of the spherical surface is accomplished while maintaining the target, illumination source, and detector in a stationary position. The imaging systems and methods may utilize a single source and a single detector, and may incorporate a THz illumination source.

Abstract: The properties inside a human tissue as well as how those properties vary over time can include information of great importance to a healthcare provider. In some cases, the tissue of interest may not be easily accessible, as a tissue that is under a cast or beneath a bandage, or may be beneath a layer of skin that makes it difficult to evaluate the tissue visually or in a non-invasive manner. The systems and methods described herein relate to monitoring tissue at a plurality of depths.

Abstract: A time-resolved fluorescence imaging (TRFI) system that images a target medium without lifetime fitting. Instead of extracting the lifetime precisely, the system images the fluorophore distribution to allow for a simple and accurate method to obtain the fluorescence image without lifetime-extraction for time-resolved fluorescence imaging. An illumination source circuit for TRFI is also disclosed that shapes the excitation pulse. In one embodiment, the illumination source comprises an LED and stub line configured for generating a linear decay profile.

Abstract: A corneal hydration sensing system includes an illumination system configured to provide an illumination beam of terahertz radiation, an optical system arranged in an optical path of the illumination system to relay and direct at least a portion of the illumination beam of terahertz radiation onto a cornea of a subject and to receive at least a portion of terahertz radiation reflected from the cornea to provide a return beam of terahertz radiation, and a detection system arranged in an optical path of the return beam of terahertz radiation. The detection system is configured to provide a detection signal from detecting at least a portion of the return beam of terahertz radiation. The corneal hydration sensing system also includes a signal processing system configured to communicate with the detection system to receive the detection signal. The signal processing system processes the detection signal to provide a measure of an amount of hydration sensed in the cornea of the subject.

Abstract: A corneal hydration sensing system includes an illumination system configured to provide an illumination beam of terahertz radiation, an optical system arranged in an optical path of the illumination system to relay and direct at least a portion of the illumination beam of terahertz radiation onto a cornea of a subject and to receive at least a portion of terahertz radiation reflected from the cornea to provide a return beam of terahertz radiation, and a detection system arranged in an optical path of the return beam of terahertz radiation. The detection system is configured to provide a detection signal from detecting at least a portion of the return beam of terahertz radiation. The corneal hydration sensing system also includes a signal processing system configured to communicate with the detection system to receive the detection signal. The signal processing system processes the detection signal to provide a measure of an amount of hydration sensed in the cornea of the subject.

Abstract: A device for removing compounds in tissue such as, for example, tattoo pigment compounds in skin tissue includes a detector for detecting the peak optical absorption of the compound, a laser source, wherein the wavelength is tuned or selected based on the peak optical absorption of the compound in the skin. The device further includes a delivery member for delivering radiation from the laser source to the tissue. Compounds such as tattoo pigment compounds are removed by detecting the peak optical absorption of the tattoo pigments or photofragments thereof in tissue with the detector. The wavelength of the laser source is adjusted based on the peak optical absorption of the compound in the tissue, and delivers radiation at the adjusted (or non-adjusted) wavelength from the laser source to the compound in the tissue with the delivery member.

Abstract: Methods and devices for Laser Induced Fluorescence Attenuation Laser Induced Fluorescence Attenuation Spectroscopy (LIFAS) Spectrocopy, including, in particular, methods and devices for the detection of ischemia and hypoxia in biological tissue.

Abstract: A method of analysis of organic matter, called Time-Resolved, Laser-Induced Fluorescence Spectroscopy (TR-LIFS), characterizes and discriminates certain matter, such as tissue, by investigating the fluoresence response of the protein and lipid fluorophore components in both the spectral domain and time domain. This method is more robust than prior methods as (1) can investigate the matter at muplitple wavelengths and even across an entire spectrum and (2) is more sensitive to picking up weaker fluorescence signals such as that from lipids. A detailed study of the use of TR-LIFs for the charaterization of arterial wall tisse is described. A system and instrumentation for practicing the novel method is also disclosed.

Abstract: A glucose monitor, and related method, determines the concentration of glucose in a sample with water, using a predictive regression model. The glucose monitor illuminates the sample with ultraviolet excitation light that induces the water and any glucose present in the sample to emit return light that includes raman scattered light and glucose emission or fluorescence light. The return light is monitored and processed using a predictive regression model to determine the concentration of glucose in the sample. The predictive regression model accounts for nonlinearities between the glucose concentration and intensity of return light within different wavelength bands at a predetermined excitation light energy or the intensity of return light within a predetermined wavelength band at different excitation energy levels. A fiber-optic waveguide is used to guide the excitation light from a laser excitation source to the sample and the return light from the sample to a sensor.

Abstract: The Laser Induced Fluorescence Attenuation Spectroscopy (LIFAS) method and apparatus preferably include a source adapted to emit radiation that is directed at a sample volume in a sample to produce return light from the sample, such return light including modulated return light resulting from modulation by the sample, a first sensor, displaced by a first distance from the sample volume for monitoring the return light and generating a first signal indicative of the intensity of return light, a second sensor, displaced by a second distance from the sample volume, for monitoring the return light and generating a second signal indicative of the intensity of return light, and a processor associated with the first sensor and the second sensor and adapted to process the first and second signals so as to determine the modulation of the sample.

Abstract: The Laser Induced Fluorescence Attenuation Spectroscopy (LIFAS) method and apparatus preferably include a source adapted to emit radiation that is directed at a sample volume in a sample to produce return light from the sample, such return light including modulated return light resulting from modulation by the sample, a first sensor, displaced by a first distance from the sample volume for monitoring the return light and generating a first signal indicative of the intensity of return light, a second sensor, displaced by a second distance from the sample volume, for monitoring the return light and generating a second signal indicative of the intensity of return light, and a processor associated with the first sensor and the second sensor and adapted to process the first and second signals so as to determine the modulation of the sample.