Abstract: A system and method for determining volume-related parameters of a biological tissue, such as ocular tissue, include a light source for projecting light towards the biological tissue, a receiver for receiving light reflected from the biological tissue at two spectral wavelengths, and an image acquisition system in communication with the receiver for forming an image from the reflected light at each wavelength. A processor applies a mathematical model to the image which compares the absorption of light by the biological tissue at a selected image point at each of the two spectral wavelengths to determine the volume-related parameters, such as the relative thickness and material properties, of the biological tissue at that location.

Abstract: A sensor system for determining glucose concentration in a tear fluid sample includes a working electrode including an immobilized glucose oxidase enzyme portion for reacting with glucose in the tear fluid sample, and a selectivity portion for enhancing the selectivity for glucose over electroactive interferent species in the tear fluid sample. Alternatively, a vessel for receiving the tear fluid sample may include the enzyme portion on an inner wall thereof. A reference electrode is disposed adjacent the working electrode, wherein the electrochemical reaction of the enzyme portion with glucose in the tear fluid sample generates a current related to the glucose concentration in the tear fluid sample.

Abstract: A sensor system for determining glucose concentration in a tear fluid sample includes a working electrode including an immobilized glucose oxidase enzyme portion for reacting with glucose in the tear fluid sample, and a selectivity portion for enhancing the selectivity for glucose over electroactive interferent species in the tear fluid sample. Alternatively, a vessel for receiving the tear fluid sample may include the enzyme portion on an inner wall thereof. A reference electrode is disposed adjacent the working electrode, wherein the electrochemical reaction of the enzyme portion with glucose in the tear fluid sample generates a current related to the glucose concentration in the tear fluid sample.

Abstract: A system and method for determining volume-related parameters of a biological tissue, such as ocular tissue, include a light source for projecting light towards the biological tissue, a receiver for receiving light reflected from the biological tissue at two spectral wavelengths, and an image acquisition system in communication with the receiver for forming an image from the reflected light at each wavelength. A processor applies a mathematical model to the image which compares the absorption of light by the biological tissue at a selected image point at each of the two spectral wavelengths to determine the volume-related parameters, such as the relative thickness and material properties, of the biological tissue at that location.

Abstract: An apparatus and method for the self-measurement of intraocular pressure utilize a tonometer disposed within a housing and having a tonometer tip. The apparatus further includes an adjustment mechanism in communication with the tonometer for positioning the tonometer tip in contact with a test eye of the user, and an illuminator mounted within the housing adjacent the tonometer tip. A receiver is aligned with the tonometer tip for receiving an applanation pattern created by contact of the tonometer tip with the test eye, and a display is provided in communication with the receiver for displaying the applanation pattern to an observing eye of the user. The intraocular pressure of the test eye is determined from a force applied by the tonometer tip upon observation of a selected applanation pattern by the observing eye.

Abstract: An apparatus and method for the self-measurement of intraocular pressure utilize a tonometer disposed within a housing and having a tonometer tip. The apparatus further includes an adjustment mechanism in communication with the tonometer for positioning the tonometer tip in contact with a test eye of the user, and an illuminator mounted within the housing adjacent the tonometer tip. A receiver is aligned with the tonometer tip for receiving an applanation pattern created by contact of the tonometer tip with the test eye, and a display is provided in communication with the receiver for displaying the applanation pattern to an observing eye of the user. The intraocular pressure of the test eye is determined from a force applied by the tonometer tip upon observation of a selected applanation pattern by the observing eye.

Abstract: A method and apparatus for non-invasively determining the concentration of a substance in blood, such as glucose, include a sample portion arranged for contacting an eye region of a user to obtain a tear fluid sample, a sensor in communication with the sample portion for generating a signal related to the tear substance concentration, and a processor in communication with the sensor for determining a blood substance concentration corresponding to the tear substance concentration.

Abstract: A method and apparatus for non-invasively determining the concentration of a substance in blood, such as glucose, include a sample portion arranged for contacting an eye region of a user to obtain a tear fluid sample, a sensor in communication with the sample portion for generating a signal related to the tear substance concentration, and a processor in communication with the sensor for determining a blood substance concentration corresponding to the tear substance concentration.

Abstract: A method and apparatus for non-invasively determining the concentration of a substance in blood, such as glucose, include a sample portion arranged for contacting an eye region of a user to obtain a tear fluid sample, a sensor in communication with the sample portion for generating a signal related to the tear substance concentration, and a processor in communication with the sensor for determining a blood substance concentration corresponding to the tear substance concentration.