Abstract:
A reagentless whole-blood analyte detection system (200, 400, 450, 1000, 1100) that is capable of being deployed near a patient has a source (220) capable of emitting a beam of radiation that includes a spectral band. The whole-blood system (200, 400, 450, 1000, 1100) also has at least one detector (250, 1152, 1154) in an optical path of the beam. The whole-blood system (200, 400, 450, 1000, 1100) also has a housing (402, 452) that is configured to house the source (220) and the detector(s) (250, 1152, 1154). The whole-blood system (200, 400, 450, 1000, 1100) also has a sample element (240, 305, 605, 805, 885, 905, 1040, 1205, 1305, 1355, 1405) that is situated in the optical path of the beam. The sample element (240, 305, 605, 805, 885, 905, 1040, 1205, 1305, 1355, 1405) has a sample cell (242, 310, 610, 810) and a sample cell wall (244, 330, 335) that does not eliminate transmittance of the beam of radiation in the spectral band.
Abstract:
A device and method are provided for use with a noninvasive optical measurement system, such as a thermal gradient spectrometer, for improved determination of analyte concentrations within living tissue. In one embodiment, a wearable window is secured to a patient's forearm thereby isolating a measurement site on the patient's skin for determination of blood glucose levels. The wearable window effectively replaces a window of the spectrometer, and thus forms an interface between the patient's skin and a thermal mass window of the spectrometer. When the spectrometer must be temporarily removed from the patient's skin, such as to allow the patient mobility, the wearable window is left secured to the forearm so as to maintain a consistent measurement site on the skin. When the spectrometer is later reattached to the patient, the wearable window will again form an interface between the spectrometer and the same location of skin as before.
Abstract:
A device and method for selecting and stabilizing proper sites for the measurement of the concentration of an analyte, for example glucose, within the tissue of a subject or patient are disclosed. One embodiment of the device immobilizes the subject's forearm and finger, thereby stabilizing measurement sites thereon for exposure to a noninvasive monitor which captures analyte concentration data within the subject's skin. The method involves the choice of a location on the subject's body at which to take the analyte measurement, preferably based on the amount of time that has elapsed since the last time the subject ate.
Abstract:
Described are embodiments including methods and devices for venting a handpiece of a medical device. These embodiments provide a vent for the handpiece. A porous membrane is positioned over an opening of the vent to allow gas, including steam, to enter and escape from the handpiece and prevent liquids from entering the handpiece. Other embodiments include methods and devices for holding an ultrasonic driver assembly within a handpiece and preventing the ultrasonic driver assembly from rotating within the handpiece. These embodiments include positioning the ultrasonic driver assembly such that the ultrasonic driver assembly is held in place at a node of the ultrasonic driver assembly and an anti-rotation mechanism is also located at the node.
Abstract:
A method determines an analyte concentration in a sample including the analyte and a substance. The method (100) includes providing an absorption spectrum of the sample (200). The absorption spectrum has an absorption baseline. The method further includes shifting the absorption spectrum (300) so that the absorption baseline equals a selected absorption value in a selected wavelength range. The method further includes subtracting a substance contribution (400) from the absorption spectrum. Thus, the method provides a corrected absorption spectrum substantially free of a contribution from the substance.
Abstract:
A method and apparatus for monitoring glucose, ethyl alcohol and other blood constituents in a noninvasive manner. The measurements are made by monitoring infrared absorption of the desired blood constituent in the long infrared wavelength range. The long wavelength infrared energy generated by source (400) is passed through a finger (406). To prevent the high energy source from burning or causing patient discomfort, shutter (404) and bandpass filters (410) cause only short bursts of energy to be sent through the finger with a very low duty cycle and low optical bandwidth. The bursts are further synchronized by shutter (404) with systole and diastole of the cardiac cycle so that only two pulses are sent per heart beat, one during diastole and one during systole. The detection signals measured at detectors (412) during application of these bursts of energy are used to calculate the concentration of blood constituents in accordance with a polynomial equation.
Abstract:
A noncontact infrared tympanic thermometer which does not require environmental stabilization or waveguide temperature control because it utilizes an optically stabilized infrared detector for detecting the infrared energy emitted by the tympanic membrane. This stability is accomplished by locating a neutral density filter (164) over half of the optical aperture (162) of the detector package (16) such that the neutral density filter (164) ''shadows'' only one of two thermopile channels (163) for detecting the infrared energy emitted by the tympanic membrane. The two thermopile channels (163) are connected in series opposition such that any optical signal equally present in both channels will yield a zero net output. Since the infrared energy emitted by the walls (161) of the detector package (16) reach each detector (163) equally, the effects of these emissions on the temperature measurement are eliminated.
Abstract:
A device and method are provided for use with a noninvasive optical measurement system, such as a thermal gradient spectrometer, for improved determination of analyte concentrations within living tissue. In one embodiment, a wearable window (100) is secured to a patient's forearm thereby isolating a measurement site on the patient's skin for determination of blood glucose levels. The wearable window (100) effectively replaces a window of the spectrometer, and thus forms an interface between the patient's skin and a thermal mass window of the spectrometer. When the spectrometer must be temporarily removed from the patient's skin, such as to allow the patient mobility, the wearable window (100) is left secured to the forearm so as to maintain a consistent measurement site on the skin. When the spectrometer is later reattached to the patient, the wearable window (100) will again form an interface between the spectrometer and the same location of skin as before.
Abstract:
Described are embodiments including methods and devices for venting a handpiece of a medical device. These embodiments provide a vent for the handpiece. A porous membrane is positioned over an opening of the vent to allow gas, including steam, to enter and escape from the handpiece and prevent liquids from entering the handpiece. Other embodiments include methods and devices for holding an ultrasonic driver assembly within a handpiece and preventing the ultrasonic driver assembly from rotating within the handpiece. These embodiments include positioning the ultrasonic driver assembly such that the ultrasonic driver assembly is held in place at a node of the ultrasonic driver assembly and an anti-rotation mechanism is also located at the node.
Abstract:
An analyte concentration monitoring system having network-based communication features (600) which provide a link between an analyte detection system (602) and a centralized computer (604). The analyte detection system has a processor (610) that calculates analyte concentration in accordance with software (612) executable by the processor. Under certain conditions, the software (612) needs to be updated. Accordingly, when the analyte detection system is connected to the centralized computer, the centralized computer determines whether a software update (614) is needed. If a software update is needed, then the centralized computer conveniently provides the software update to the analyte detection system without intervention from a user.