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: 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. The sample includes the analyte and a substance. The method includes providing absorption data of the sample. The method further includes providing reference absorption data of the substance. The method further includes calculating a substance contribution of the absorption data. The method further includes subtracting the substance contribution from the absorption data, thereby providing corrected absorption data substantially free of a contribution from the substance.

Abstract: A method determines an analyte concentration in a sample. The sample includes the analyte and a substance. The method includes providing absorption data of the sample. The method further includes providing reference absorption data of the substance. The method further includes calculating a substance contribution of the absorption data. The method further includes subtracting the substance contribution from the absorption data, thereby providing corrected absorption data substantially free of a contribution from the substance.

Abstract: A method determines an analyte concentration in a sample. The sample includes the analyte and a substance. The method includes providing absorption data of the sample. The method further includes providing reference absorption data of the substance. The method further includes calculating a substance contribution of the absorption data. The method further includes subtracting the substance contribution from the absorption data, thereby providing corrected absorption data substantially free of a contribution from the substance.

Abstract: A method and infrared sensing device for determining the concentration of alveolar alcohol in a breath sample exhaled by a subject into an infrared sensing device. The presence of alcohol from the upper respiratory tract of the subject is detected by continuously monitoring alcohol and carbon dioxide, normalizing alcohol values with respect to carbon dioxide, calculating a difference between normalized alcohol concentration and carbon dioxide concentration over time, integrating (summing) the difference, and comparing the integrated difference with a threshold. This technique accurately and consistently detects the presence of mouth alcohol in the sample before the presence of carbon dioxide which originates in deep lung breath.

Abstract: A method determines an analyte concentration in a sample including the analyte and a substance. The method includes providing an absorption spectrum of the sample. The absorption spectrum has an absorption baseline. The method further includes shifting the absorption spectrum so that the absorption baseline approximately equals a selected absorption value in a selected absorption wavelength range. The method further includes subtracting a substance contribution from the absorption spectrum. Thus, the method provides a corrected absorption spectrum substantially free of a contribution from the substance.

Abstract: A reagentless whole-blood analyte detection system that is capable of being deployed near a patient has a source capable of emitting a beam of radiation that includes a spectral band. The whole-blood system also has a detector in an optical path of the beam. The whole-blood system also has a housing that is configured to house the source and the detector. The whole-blood system also has a sample element that is situated in the optical path of the beam. The sample element has a sample cell and a sample cell wall that does not eliminate transmittance of the beam of radiation in the spectral band.

Abstract: A method uses spectroscopy to determine an analyte concentration in a sample. The method includes producing an absorbance spectrum of the sample. The method further includes shifting the absorbance spectrum to zero in a wavelength region. The method further includes subtracting a water or other substance contribution from the absorbance spectrum.

Abstract: A method of determining the analyte concentration of a test sample is described. A temperature gradient is introduced in the test sample and infrared radiation detectors measure radiation at selected analyte absorbance peak and reference wavelengths. Reference and analytical signals are detected. In the presence of the selected analyte, parameter differences between reference and analytical signals are detectable. These parameter differences, having a relationship to analyte concentration, are measured, correlated, and processed to determine analyte concentration in the test sample. Accuracy is enhanced by inducing a periodically modulated temperature gradient in the test sample. The analytical and reference signals may be measured continuously and the parameter difference integrated over the measurement period to determine analyte concentration.

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 reagentless whole-blood analyte detection system that is capable of being deployed near a patient has a source capable of emitting a beam of radiation that includes a spectral band. The whole-blood system also has a detector in an optical path of the beam. The whole-blood system also has a housing that is configured to house the source and the detector. The whole-blood system also has a sample element that is situated in the optical path of the beam. The sample element has a sample cell and a sample cell wall that does not eliminate transmittance of the beam of radiation in the spectral band.

Abstract: A method and apparatus of determining the analyte concentration of a test sample is described. A temperature gradient is introduced into the test sample and infrared radiation detectors measure radiation at selected analyte absorbance peak and reference wavelengths. The modulation of the temperature gradient is controlled by a surface temperature modulation. A transfer function is determined that relates the surface temperature modulation to the modulation of the measured infrared radiation. Reference and analytical signals are detected. In the presence of the selected analyte, phase and magnitude differences in the transfer function are detected. These phase and magnitude differences, having a relationship to analyte concentration, are measured, correlated and processed to determine analyte concentration in the sample.

Abstract: An analyte concentration monitoring system having network-based communication features which provide a link between an analyte detection system and a centralized computer. The analyte detection system has a processor that calculates analyte concentration in accordance with software executable by the processor. Under certain conditions, the software needs to be updated. Accordingly, when the analyte detection system is connected to the centralized computer, the centralized computer determines whether a software update 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.

Abstract: A method determines an analyte concentration in a sample including the analyte and a substance. The method includes providing an absorption spectrum of the sample. The absorption spectrum has an absorption baseline. The method further includes shifting the absorption spectrum so that the absorption baseline approximately equals a selected absorption value in a selected absorption wavelength range. The method further includes subtracting a substance contribution from the absorption spectrum. Thus, the method provides a corrected absorption spectrum substantially free of a contribution from the substance.

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: An analyte concentration monitoring system having network-based communication features which provide a link between an analyte detection system and a centralized computer. The analyte detection system has a processor that calculates analyte concentration in accordance with software executable by the processor. Under certain conditions, the software needs to be updated. Accordingly, when the analyte detection system is connected to the centralized computer, the centralized computer determines whether a software update 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.

Abstract: A method and apparatus of determining the analyte concentration of a test sample is described. A temperature gradient is introduced into the test sample and infrared radiation detectors measure radiation at selected analyte absorbance peak and reference wavelengths. The modulation of the temperature gradient is controlled by a surface temperature modulation. A transfer function is determined that relates the surface temperature modulation to the modulation of the measured infrared radiation. Reference and analytical signals are detected. In the presence of the selected analyte, phase and magnitude differences in the transfer function are detected. These phase and magnitude differences, having a relationship to analyte concentration, are measured, correlated and processed to determine analyte concentration in the sample.

Abstract: A method of determining the analyte concentration of a test sample is described. A temperature gradient is introduced in the test sample and infrared radiation detectors measure radiation at selected analyte absorbance peak and reference wavelengths. Reference and analytical signals are detected. In the presence of the selected analyte, parameter differences between reference and analytical signals are detectable. These parameter differences, having a relationship to analyte concentration, are measured, correlated, and processed to determine analyte concentration in the test sample. Accuracy is enhanced by inducing a periodically modulated temperature gradient in the test sample. The analytical and reference signals may be measured continuously and the parameter difference integrated over the measurement period to determine analyte concentration.

Abstract: A method determines an analyte concentration in a sample including the analyte and a substance. The method includes providing an absorption spectrum of the sample. The absorption spectrum has an absorption baseline. The method further includes shifting the absorption spectrum so that the absorption baseline approximately equals a selected absorption value in a selected absorption wavelength range. The method further includes subtracting a substance contribution from the absorption spectrum. Thus, the method provides a corrected absorption spectrum substantially free of a contribution from the substance.