Abstract: A device and method in accordance with the invention for determining the oxygen partial pressure (PO2) of a tissue by irradiating the tissue with optical radiation such that the light is emitted from the tissue, and by collecting the reflected or transmitted light from the tissue to form an optical spectrum. A spectral processor determines the PO2 level in tissue by processing this spectrum with a previously-constructed spectral calibration model. The tissue may, for example, be disposed underneath a covering tissue, such as skin, of a patient, and the tissue illuminated and light collected through the skin. Alternatively, direct tissue illumination and collection may be effected with a hand-held or endoscopic probe. A preferred system also determines pH from the same spectrum, and the processor may determine critical conditions and issue warnings based on parameter values.

Abstract: The present invention provides methods for non-invasive spectroscopic measurement of the concentration of an electrolyte, such as, sodium, potassium, or calcium ion, in a subject's blood. In one embodiment of a method according to the invention, calibration spectra are obtained from a group of subjects having variable blood electrolyte concentrations, and simultaneously blood is drawn from these subjects for measuring reference electrolyte concentrations. Standard multivariate calibration methods are employed to develop one or more calibration equations, based on the calibration spectra and the reference measurements. These calibration equations can be employed to analyze spectra obtained from a new subject to non-invasively determine the concentration of the electrolyte of interest.

Abstract: An optical probe structure for illuminating and collecting returned light from a region of tissue. The optical probe is configured with illumination and collection windows to controllably collect light from the region of tissue in vivo. The probe is designed to have a defined spacing between the fiber or fibers connected to the light source, and the fiber or fibers connected to the optical detector, so that light reaching the detector has passed through a localized region of tissue of a small and well-defined size or dimension. The probe can assay or detect tissue cell distribution, a tissue constituent such as hydrogen ions (pH), lactate, or an endogenous tissue component such as hemoglobin, myoglobin, or lipids in plaque. Measurements may indicate conditions such as metabolic state, stress, shock or ischemia in different tissues.

Abstract: A device and method in accordance with the invention for determining the oxygen partial pressure (PO2) of a tissue by irradiating the tissue with optical radiation such that the light is emitted from the tissue, and by collecting the reflected or transmitted light from the tissue to form an optical spectrum. A spectral processor determines the PO2 level in tissue by processing this spectrum with a previously-constructed spectral calibration model. The tissue may, for example, be disposed underneath a covering tissue, such as skin, of a patient, and the tissue illuminated and light collected through the skin. Alternatively, direct tissue illumination and collection may be effected with a hand-held or endoscopic probe. A preferred system also determines pH from the same spectrum, and the processor may determine critical conditions and issue warnings based on parameter values.

Abstract: A non-invasive spectral measurement for a target analyte present in a subject's tissue or blood derives spectral shapes corresponding to one or more human variability factors, such as, skin color, from spectra collected from a diverse calibration group of subjects. Another set of spectra are normalized based on the derived spectral shapes to generate a set of corrected spectra. The corrected spectra are then utilized to generate and/or enhance a calibration model for detecting and/or measuring the target analyte from one or more transderamlly obtained spectra of a subject.

Abstract: A non-invasive spectral measurement of a native, diagnostic or treatment component in blood or tissue, illuminates the back of the eye and collects return light that has passed through and been reflected from choroidal or retinal tissue. Spectral analysis detects a retinal tissue state, or detects the level of a blood or serum constituent, which may be a native constituent or a dye, marker or pharmacological agent. Time-resolved or spectral decay monitoring may be used to assess organ functioning, e.g., by administering a serum-carried indicator of uptake, clearance or binding rate for specific organs. Circulating cells or material diagnostic of different conditions may also be detected by spectral analysis, either directly, or by tagging with a suitable label.

Abstract: The present invention encompasses tools and a tool-holding retractor assembly. The retractor assembly spreads an incision and holds the incision open. At least one extension device, having a tool holder on one end, attaches to the assembly. The holder includes a selectively locking multi-axis adjustable mounting element adapted to grip a tool shaft. The mounting element acts as a universal mounting providing rotational and sliding movement of the tool shaft. The extension device adjusts to position the tool holder peripherally of the surgical field. Once the retractor is placed, the extension device provides full access to regions below the incision. The extension device allows the surgeon to chose the insertion point and insertion angle of the tool shaft.

Abstract: The invention provides an optical method and apparatus for non-invasively determining blood hematocrit. The method includes the step of first irradiating blood with optical radiation. Radiation reflected or transmitted from the blood is then collected to determine an optical spectrum. Hematocrit is then determined by comparing this spectrum to a mathmatical model relating optical properties to blood Hematocrit.

Abstract: The invention provides an optical method and apparatus for non-invasively determining blood hematocrit. The method includes the step of first irradiating blood with optical radiation. Radiation reflected or transmitted from the blood is then collected to determine an optical spectrum. Hematocrit is then determined by comparing this spectrum to a mathematical model relating optical properties to blood Hematocrit.

Abstract: The invention provides an optical method and apparatus for determining the pH of a tissue. The method includes the step of first irradiating the tissue with optical radiation. The radiation may first pass through skin covering the tissue of interest, or may irradiate the tissue directly. Radiation reflected from the tissue is then collected to determine a reflection spectrum. pH is then determined by comparing this spectrum to a mathematical model relating optical properties to pH of the tissue.

Abstract: A tissue retrieval bag has a wide mouth and folds for insertion through an incision to a body cavity to form a flat tray and receive excised tissue. The tissue is dropped onto the floor of the bag and the mouth of the bag is then drawn back through the incision, where it drapes the opening to provide a protected tunnel to the resected tissue still lying within the cavity. The bag is preferably transparent, and the enclosed tissue may be viewed endoscopically while a morcellizer is inserted through the tunnel and operated to aspirate the tissue, so that the bag is then readily withdrawn through the incision. Alternatively, an endoscope may be inserted through the tunnel directly into the bag to monitor and control morcellation. In a preferred embodiment the tissue is resected lung tissue and, a morcellizer blade is used to selectively morcellate only the parenchyma, leaving lymphatic tissue and the bronchial tree in the bag for histologic analysis.

Abstract: A fiber optic sensor for measurement of in vivo nitric oxide concentrations in a subject. The sensor contains a nitric oxide-sensing compound in a polymer matrix attached to an optical fiber. The sensor may be placed in any blood vessel, including one within the heart of a subject for continuous measurement of nitric oxide concentrations in blood.