Abstract: An optical sampling interface system is disclosed that minimizes and compensates for errors that result from sampling variations and measurement site state fluctuations. Embodiments of the invention use a guide that does at least one of, induce the formation of a tissue meniscus, minimize interference due to surface irregularities, control variation in the volume of tissue sampled, use a two-part guide system, use a guide that controls rotation of a sample probe and allows z-axis movement of the probe, use a separate base module and sample module in conjunction with a guide, and use a guide that controls rotation. Optional components include an occlusive element and a coupling fluid.

Abstract: A method and apparatus for calibrating noninvasive or implantable glucose analyzers uses either alternative invasive glucose determinations or noninvasive glucose determinations for calibrating noninvasive or implantable glucose analyzers. Use of an alternative invasive or noninvasive glucose determination in the calibration allows minimization of errors due to sampling methodology, and spatial and temporal variations that are built into the calibration model. An additional embodiment uses statistical correlations between noninvasive and alternative invasive glucose determinations and traditional invasive glucose determinations to adjust noninvasive or alternative invasive glucose concentrations to traditional invasive glucose concentrations. The invention provides a means for calibrating on the basis of glucose determinations that reflect the matrix observed and the variable measured by the analyzer more closely.

Abstract: The invention relates to the extraction and/or presentation of glucose concentrations estimated as a function of time into a format that facilitates conveyance of the underlying information. More particularly, short term actions, such as exercise, diabetes drug treatment, and/or food intake, are correlated to glucose response profiles. Optionally, glucose concentration responses are back correlated to parameters, such as time, exercise, diabetes drug treatment and/or food intake. The resulting correlated data are output to the user in a time compressed format, in video format, and/or as a cluster allowing diagnosis and treatment information to be more readily determined and used. These information presentations are useful for both the medical professional and the end user. The information presentation is preferably used with a noninvasive, implantable, semi-continuous, and/or continuous analyte analyzer, such as a glucose concentration analyzer.

Abstract: The invention provides for transformation of a section of a data block independently of the transformation of separate or overlapping data blocks to determine a property related to the original matrix, where each of the separate or overlapping data blocks are derived from an original data matrix. The transformation enhances parameters of a first data block over a given region of an axis of the data matrix, such as signal-to-noise, without affecting analysis of a second data block derived from the data matrix. This allows for enhancement of analysis of an analyte property, such as concentration, represented within the original data matrix. In a first embodiment of the invention, a separate decomposition and factor selection for each selected data matrix is performed with subsequent score matrix concatenization. The combined score matrix is used to generate a model that is subsequently used to estimate a property, such as concentration represented in the original data matrix.

Abstract: The invention relates to a noninvasive analyzer and a method of using information determined at least in part from in-vitro spectra of tissue phantoms or analyte solutions to aid in the development of a noninvasive glucose concentration analyzer and/or in the analysis of noninvasive spectra resulting in glucose concentration estimations in the body. The preferred apparatus is a spectrometer that includes a base module and a sample module that is semi-continuously in contact with a human subject and that collects spectral measurements which are used to determine a biological parameter in the sampled tissue, such as glucose concentration. Collection of in-vitro samples is, optionally, performed on a separate instrument from the production model allowing the measurement technology to be developed on a research grade instrument and used or transferred to a target product platform or production analyzer for noninvasive glucose concentration estimation.

Abstract: A near-infrared spectrometer-based analyzer attaches continuously or semi-continuously to a human subject and is used to collect spectral measurements of a tissue sample. The spectral readings are used to estimate a biological parameter in the sampled tissue noninvasively, such as glucose concentration. The preferred apparatus is a near-infrared analyzer that includes a base module and a sample module connected together with a communication bundle. The base module contains the bulk of the analyzer, such as a spectrograph and a central processing unit with an algorithm used for converting the optical signal into a glucose concentration. The sample module is typically in a smaller module that interfaces to a tissue sample. The sample module is preferably handheld and provides minimal sampling distortion due to heat or pressure.

Abstract: An optical sampling interface system minimizes and compensates error resulting from sampling variations and measurement site state fluctuations. Components include: An optical probe placement guide having an aperture wherein the optical probe is received, facilitates repeatable placement accuracy on surface of a tissue measurement site with minimal, repeatable disturbance to surface tissue. The aperture creates a tissue meniscus that minimizes interference due to surface irregularities and controls variation in tissue volume sampled; an occlusive element placed over the tissue meniscus isolates the meniscus from environmental fluctuations, stabilizing hydration at the site and thus, surface tension; an optical coupling medium eliminates air gaps between skin surface and optical probe; a bias correction element applies a bias correction to spectral measurements, and associated analyte measurements. When the guide is replaced, a new bias correction is determined for measurements done with the new placement.

Abstract: A near IR spectrometer-based analyzer attaches continuously or semi-continuously to a human subject and collects spectral measurements for determining a biological parameter in the sampled tissue, such as glucose concentration. The analyzer includes an optical system optimized to target the cutaneous layer of the sampled tissue so that interference from the adipose layer is minimized. The optical system includes at least one optical probe. Spacing between optical paths and detection fibers of each probe and between probes is optimized to minimize sampling of the adipose subcutaneous layer and to maximize collection of light backscattered from the cutaneous layer. Penetration depth is optimized by limiting range of distances between paths and detection fibers. Minimizing sampling of the adipose layer greatly reduces interference contributed by the fat band in the sample spectrum, increasing signal-to-noise ratio.

Abstract: A method and apparatus for easing the use of an optically based noninvasive analyzer is presented. More particularly, a simplified algorithm is used that removes the daily requirement of collecting and using a noninvasive spectrum to update a calibration model. In another embodiment, a guide is used to substantially reduce variation in sample probe placement in relation to a skin tissue sampling site, resulting in the ability to maintain calibration performance with the use of a reference analyte concentration, with or without the use of a reference spectrum collected nearby in time.

Abstract: The invention involves the monitoring of a biological parameter through a compact analyzer. The preferred apparatus is a spectrometer based system that is attached continuously or semi-continuously to a human subject and collects spectral measurements that are used to determine a biological parameter in the sampled tissue. The preferred target analyze is glucose. The preferred analyzer is a near-IR based glucose analyzer for determining the glucose concentration in the body.