Abstract: An apparatus carries out measurements of blood glucose in a repeatable, non-invasive manner by measurement of the rate of regeneration of retinal visual pigments, such as cone visual pigments. The rate of regeneration of visual pigments is dependent upon the blood glucose concentration, and by measuring the visual pigment regeneration rate, blood glucose concentration can be accurately determined. This apparatus exposes the retina to light of selected wavelengths in selected distributions and subsequently analyzes the reflection (as color or darkness) from a selected portion of the exposed region of the retina, preferably from the fovea.

Abstract: An apparatus carries out measurements of blood glucose in a repeatable, non-invasive manner by measurement of the rate of regeneration of retinal visual pigments, such as cone visual pigments. The rate of regeneration of visual pigments is dependent upon the blood glucose concentration, and by measuring the visual pigment regeneration rate, blood glucose concentration can be accurately determined. This apparatus exposes the retina to light of selected wavelengths in selected distributions and subsequently analyzes the reflection (as color or darkness) from a selected portion of the exposed region of the retina, preferably from the fovea.

Abstract: An apparatus carries out measurements of blood glucose in a repeatable, non-invasive manner by measurement of the rate of regeneration of retinal visual pigments, such as cone visual pigments. The rate of regeneration of visual pigments is dependent upon the blood glucose concentration, and by measuring the visual pigment regeneration rate, blood glucose concentration can be accurately determined. This apparatus exposes the retina to light of selected wavelengths in selected distributions and subsequently analyzes the reflection (as color or darkness) from a selected portion of the exposed region of the retina, preferably from the fovea.

Abstract: An apparatus carries out measurements of blood glucose in a repeatable, non-invasive manner by measurement of the rate of regeneration of retinal visual pigments, such as cone visual pigments. The rate of regeneration of visual pigments is dependent upon the blood glucose concentration, and by measuring the visual pigment regeneration rate, blood glucose concentration can be accurately determined. This apparatus exposes the retina to light of selected wavelengths in selected distributions and subsequently analyzes the reflection (as color or darkness) from a selected portion of the exposed region of the retina, preferably from the fovea.

Abstract: Blood glucose concentrations are measured by non-invasive methods and apparatus using visual pigment bleaching in conjunction with psychophysical methodologies. Bleaching light of selected wavelengths is projected through the pupil of the eye of an observer onto the fundus to bleach visual pigments in the eye. The observer's psychophysical response to a visual stimulus is then measured to obtain information regarding the rate of regeneration of the visual pigments. From the rate of pigment regeneration, blood glucose concentrations are measured accurately. The psychophysical methodologies that may be used with the invention include visual acuity tests and color-matching tests.

Abstract: The determination of blood glucose in an individual is carried out by projecting illuminating light into an eye of the individual to illuminate the retina with the light having wavelengths that are absorbed by rhodopsin and with the intensity of the light varying in a prescribed temporal manner. The light reflected from the retina is detected to provide a signal corresponding to the intensity of the detected light, and the detected light signal is analyzed to determine the changes in form from that of the illuminating light. For a biased sinusoidal illumination, these changes can be expressed in terms of harmonic content of the detected light. The changes in form of the detected light are related to the ability of rhodopsin to absorb light and regenerate, which in turn is related to the concentration of blood glucose, allowing a determination of the relative concentration of blood glucose.

Abstract: The determination of blood glucose in an individual is carried out by projecting illuminating light into an eye of the individual to illuminate the retina with the light having wavelengths that are absorbed by rhodopsin and with the intensity of the light varying in a prescribed temporal manner. The light reflected from the retina is detected to provide a signal corresponding to the intensity of the detected light, and the detected light signal is analyzed to determine the changes in form from that of the illuminating light. For a biased sinusoidal illumination, these changes can be expressed in terms of harmonic content of the detected light. The changes in form of the detected light are related to the ability of rhodopsin to absorb light and regenerate, which in turn is related to the concentration of blood glucose, allowing a determination of the relative concentration of blood glucose.

Abstract: The determination of blood glucose in an individual is carried out by projecting illuminating light into an eye of the individual to illuminate the retina with the light having wavelengths that are absorbed by rhodopsin and with the intensity of the light varying in a prescribed temporal manner. The light reflected from the retina is detected to provide a signal corresponding to the intensity of the detected light, and the detected light signal is analyzed to determine the changes in form from that of the illuminating light. For a biased sinusoidal illumination, these changes can be expressed in terms of harmonic content of the detected light. The changes in form of the detected light are related to the ability of rhodopsin to absorb light and regenerate, which in turn is related to the concentration of blood glucose, allowing a determination of the relative concentration of blood glucose.

Abstract: A protective cover for medical imaging devices of the type having a probe with an optical system at a distal end includes a sheath of plastic material formed to enclose at least a portion of the probe and a transparent head secured to the sheath at a distal end of the cover. The transparent head provides a transparent window at the distal end of the probe to allow light to enter the probe and be imaged in a normal manner. Indicia are formed on the transparent head and are imaged by the medical imaging device. The image is then analyzed to determine if the indicia as shown in the image correspond to a preselected pattern, which may be one of a group of patterns which provide indications concerning the nature of the cover. If a pattern is recognized, the information corresponding to that pattern can be provided to an operator; if no pattern is recognized or if the pattern corresponds to an improper cover for the particular imaging device, a warning can be provided to the operator or the device disabled.

Abstract: Illuminating light of selected wavelengths in the visible or infrared range is projected through the pupil of the eye onto the fundus, and the light reflected back and out through the pupil is detected and analyzed, preferably using the area of the optic disk for analyzing the retinal vessels overlying the optic disk. Specific wavelengths of illuminating light may be chosen for each blood component to be analyzed depending on the spectral characteristics of the substance being analyzed. The reflected image from the retina may be used to measure non-photoreactive blood components such as hemoglobin, and photoreactive components such as bilirubin. For the measurement of photoreactive components, images may be taken before and after, or during, illumination of the eye with light at wavelengths which will affect the photoreactive analyte, enabling measurements of the concentration of the analyte.

Abstract: Illuminating light of selected wavelengths in the visible or infrared range is projected through the pupil of the eye onto the fundus, and the light reflected back and out through the pupil is detected and analyzed, preferably using the area of the optic disk for analyzing the retinal vessels overlying the optic disk. Specific wavelengths of illuminating light may be chosen for each blood component to be analyzed depending on the spectral characteristics of the substance being analyzed. The reflected image from the retina may be used to measure non-photoreactive blood components such as hemoglobin, and photoreactive components such as bilirubin. For the measurement of photoreactive components, images may be taken before and after, or during, illumination of the eye with light at wavelengths which will affect the photoreactive analyte, enabling measurements of the concentration of the analyte.

Abstract: Illuminating light of selected wavelengths in the visible or infrared range is projected through the pupil of the eye onto the fundus, and the light reflected back and out through the pupil is detected and analyzed, preferably using the area of the optic disk for analyzing the retinal vessels overlying the optic disk. Specific wavelengths of illuminating light may be chosen for each blood component to be analyzed depending on the spectral characteristics of the substance being analyzed. The reflected image from the retina may be used to measure non-photoreactive blood components such as hemoglobin, and photoreactive components such as bilirubin. For the measurement of photoreactive components, images may be taken before and after, or during, illumination of the eye with light at wavelengths which will affect the photoreactive analyte, enabling measurements of the concentration of the analyte.