Abstract: The present disclosure relates to systems and methods for determining the renal glomerular filtration rate or assessing the renal function in a patient in need thereof. The system includes a computing device, a power supply, one or more sensors, and at least one tracer agent that fluoresces when exposed to electromagnetic radiation. The electromagnetic radiation is detected using the sensors, and the rate in which the fluorescence decreases in the patient is used to calculate the renal glomerular filtration rate in the patient.

Abstract: A method for determining a glomerular filtration rate (GFR) in a patient includes administering to said patient a compound of Formula I and transdermally measuring spectral energy emitted by the compound of Formula I over a measurement time window. The spectral energy is emitted by the compound of Formula I in response to electromagnetic radiation delivered to the compound of Formula I. The method also includes determining the GFR in said patient based on the measured spectral energy emitted by the compound of Formula I over the measurement time window by fitting an exponential function to the spectral energy as a function of time or a linear function to the log of the spectral energy as a function of time to calculate a rate constant associated with renal clearance over the measurement time window and directly related to the GFR normalized to a body size metric of the patient.

Abstract: The present disclosure relates to systems and methods for determining the renal glomerular filtration rate or assessing the renal function in a patient in need thereof. The system includes a computing device, a power supply, one or more sensors, and at least one tracer agent that fluoresces when exposed to electromagnetic radiation. The electromagnetic radiation is detected using the sensors, and the rate in which the fluorescence decreases in the patient is used to calculate the renal glomerular filtration rate in the patient.

Abstract: The present disclosure relates to systems and methods for determining the renal glomerular filtration rate or assessing the renal function in a patient in need thereof. The method includes administering a pyrazine compound of Formula I to a patient and monitoring the rate in which the kidneys of the patient eliminate the pyrazine from the systemic circulation of the patient. The pyrazine compound fluoresces when exposed to electromagnetic radiation which is detected using one or more sensors. The rate in which the fluorescence decreases in the patient is used to calculate the renal glomerular filtration rate in the patient.

Abstract: This invention provides, e.g., devices for detection of particle concentrations in a vessel in real time from outside the vessel. The device is attached to the vessel so that light from an optic fiber enters a media of the vessel, is scattered by the particles, and the scattered light received by a second optic fiber. The received light is transmitted to a detector, generating a signal to a processor for determination of a particle concentration.

Abstract: A sensor head is provided. In any of the various aspects of the invention, the sensor head has a housing enclosing at least two light sources configured to deliver light to a patient and comprising a blue LED first light source that delivers light at an excitatory wavelength and a green LED second light source, and at least one light detector configured to detect light at an emission wavelength from the patient. The sensor is useful for non-invasive monitoring of fluorescent tracers agents.

Abstract: This invention provides, e.g., devices for detection of particle concentrations in a vessel in real time from outside the vessel. The device is attached to the vessel so that light from an optic fiber enters a media of the vessel, is scattered by the particles, and the scattered light received by a second optic fiber. The received light is transmitted to a detector, generating a signal to a processor for determination of a particle concentration.

Abstract: This invention provides methods and devices to measure particle suspension concentrations in the presence of potential interferents. Particle back-scatter readings are taken at light wavelengths that are absorbed by the medium before interacting with surrounding objects. Source-detector spacings are minimized compared to the mean absorbance path length of light, thereby maximizing the range of sensitivity to particle concentration. Discrimination against potentially interfering particles, such as bubbles, is provided by mapping the signal distribution against the central signal value and/or by the use of statistical measures with reduced dependence on outliers. The methods and devices allow accurate particle concentration readings over a wide range of concentration in environments crowded with potentially interfering objects and in the presence of variable concentrations and sizes of potentially interfering particles.

Abstract: The present disclosure relates to systems and methods for determining the renal glomerular filtration rate or assessing the renal function in a patient in need thereof. The system includes a computing device, a power supply, one or more sensors, and at least one tracer agent that fluoresces when exposed to electromagnetic radiation. The electromagnetic radiation is detected using the sensors, and the rate in which the fluorescence decreases in the patient is used to calculate the renal glomerular filtration rate in the patient.

Abstract: This invention provides methods and devices to measure particle suspension concentrations in the presence of potential interferents. Particle back-scatter readings are taken at light wavelengths that are absorbed by the medium before interacting with surrounding objects. Source-detector spacings are minimized compared to the mean absorbance path length of light, thereby maximizing the range of sensitivity to particle concentration. Discrimination against potentially interfering particles, such as bubbles, is provided by mapping the signal distribution against the central signal value and/or by the use of statistical measures with reduced dependence on outliers. The methods and devices allow accurate particle concentration readings over a wide range of concentration in environments crowded with potentially interfering objects and in the presence of variable concentrations and sizes of potentially interfering particles.

Abstract: This invention provides methods and devices to measure particle suspension concentrations in the presence of potential interferents. Particle back-scatter readings are taken at light wavelengths that are absorbed by the medium before interacting with surrounding objects. Source-detector spacings are minimized compared to the mean absorbance path length of light, thereby maximizing the range of sensitivity to particle concentration. Discrimination against potentially interfering particles, such as bubbles, is provided by mapping the signal distribution against the central signal value and/or by the use of statistical measures with reduced dependence on outliers. The methods and devices allow accurate particle concentration readings over a wide range of concentration in environments crowded with potentially interfering objects and in the presence of variable concentrations and sizes of potentially interfering particles.

Abstract: This invention provides methods and devices to measure particle suspension concentrations in the presence of potential interferents. Particle back-scatter readings are taken at light wavelengths that are absorbed by the medium before interacting with surrounding objects. Source-detector spacings are minimized compared to the mean absorbance path length of light, thereby maximizing the range of sensitivity to particle concentration. Discrimination against potentially interfering particles, such as bubbles, is provided by mapping the signal distribution against the central signal value and/or by the use of statistical measures with reduced dependence on outliers. The methods and devices allow accurate particle concentration readings over a wide range of concentration in environments crowded with potentially interfering objects and in the presence of variable concentrations and sizes of potentially interfering particles.

Abstract: This invention provides methods and devices to measure particle suspension concentrations in the presence of potential interferents. Particle back-scatter readings are taken at light wavelengths that are absorbed by the medium before interacting with surrounding objects. Source-detector spacings are minimized compared to the mean absorbance path length of light, thereby maximizing the range of sensitivity to particle concentration. Discrimination against potentially interfering particles, such as bubbles, is provided by mapping the signal distribution against the central signal value and/or by the use of statistical measures with reduced dependence on outliers. The methods and devices allow accurate particle concentration readings over a wide range of concentration in environments crowded with potentially interfering objects and in the presence of variable concentrations and sizes of potentially interfering particles.

Abstract: This invention provides methods and devices to measure particle suspension concentrations in the presence of potential interferents. Particle back-scatter readings are taken at light wavelengths that are absorbed by the medium before interacting with surrounding objects. Source-detector spacings are minimized compared to the mean absorbance path length of light, thereby maximizing the range of sensitivity to particle concentration. Discrimination against potentially interfering particles, such as bubbles, is provided by mapping the signal distribution against the central signal value and/or by the use of statistical measures with reduced dependence on outliers. The methods and devices allow accurate particle concentration readings over a wide range of concentration in environments crowded with potentially interfering objects and in the presence of variable concentrations and sizes of potentially interfering particles.

Abstract: Systems, methods, and devices for obtaining consistently reproducible diagnostic measurements with a photoplethysmographic sensor are provided. In one embodiment, a method for obtaining such a diagnostic measurement includes applying a pressure between a photoplethysmographic sensor and a patient, increasing the pressure until the photoplethysmographic sensor outputs a plethysmographic waveform of minimal amplitude, decreasing the pressure by a predetermined fraction, and obtaining a diagnostic measurement using the photoplethysmographic sensor. The pressure may be applied using a pressure device that includes, for example, a clip, a wrap, an inflatable balloon or bladder, or an inflatable cuff, or any combination thereof.

Abstract: The present invention comprises methods and systems/devices for non-invasively measuring birefringent tissues (e.g. collagen) and changes during treatment of tissue, e.g., denaturation by the application of RF energy, through linear dichroism, circular dichroism, or birefringence. The invention optionally uses polarization sensitive optical measurements to discriminate between denaturation of unidirectionally oriented strands of collagen, such as a ligament or tendon, and denaturation of planar collagen surfaces, such as the dermal layer of the skin or collagen in joint capsules.

Abstract: The present invention comprises methods and systems/devices for non-invasively measuring and/or altering collagen structures before, during and after treatment, e.g., by the application of RF energy, of tissues that comprise such collagen structures.

Abstract: This invention provides a novel methods and devices for measurement of particle concentration or changes in particle concentration over a wide linear range. The invention comprises one or more radiation sources and one or more detectors contained in a housing which is interfaced to a medium containing particulate matter. The one or more radiation sources are directed into the medium, scattered or transmitted by the particulate matter, and then some portion of the radiation is detected by the one or more detectors. Methods for confining the measurement to a specific volume within the medium are described. Algorithms are provided for combining the signals generated by multiple source-detector pairs in a manner that results in a wide linear range of response to changes in particle concentration. In one embodiment the sensor provides non-invasive measurements of biomass in a bioreactor. In another embodiment an immersible probe design is described, which may be suited for one-time use.

Abstract: Systems, methods, and devices for obtaining consistently reproducible diagnostic measurements with a photoplethysmographic sensor are provided. In one embodiment, a method for obtaining such a diagnostic measurement includes applying a pressure between a photoplethysmographic sensor and a patient, increasing the pressure until the photoplethysmographic sensor outputs a plethysmographic waveform of minimal amplitude, decreasing the pressure by a predetermined fraction, and obtaining a diagnostic measurement using the photoplethysmographic sensor. The pressure may be applied using a pressure device that includes, for example, a clip, a wrap, an inflatable balloon or bladder, or an inflatable cuff, or any combination thereof.

Abstract: Devices and methods for measuring body fluid-related metric using spectrophotometry that may be used to facilitate diagnosis and therapeutic interventions aimed at restoring body fluid balance. In one embodiment, the present invention provides a device for measuring a body-tissue water content metric as a fraction of the fat-free tissue content of a patient using optical spectrophotometry. The device includes a probe housing configured to be placed near a tissue location which is being monitored; light emission optics connected to the housing and configured to direct radiation at the tissue location; light detection optics connected to the housing and configured to receive radiation from the tissue location; and a processing device configured to process radiation from the light emission optics and the light detection optics to compute the metric where the metric includes a ratio of the water content of a portion of patient's tissue in relation to the lean or fat-free content of a portion of patient's tissue.