Abstract: The present invention is directed to an interconnect for an implantable medical device. The interconnect includes a first conductive layer, a second conductive layer introduced over the first conductive layer, and a third conductive layer introduced over the second conductive layer. One of the first conductive layer, the second conductive layer, and the third conductive layer comprises titanium-niobium (Ti—Nb).

Abstract: A miniaturized spectrometer is adapted for placement within a body near tissue to be characterized. The spectrometer includes a light source and a plurality of light detectors. The light source generates light to illuminate the tissue. The detectors detect optical signals from the illuminated tissue and convert these optical signals to electrical signals. The miniaturized spectrometer can be disposed at the distal end of an interventional device. Optical conduits, such as fiber optic cables or strands, extending the length of the interventional device are not required when the miniature spectrometer is employed.

Abstract: A system includes multiple slave devices implanted in a human body, wherein each slave device includes a communication module operable to receive transmitted communications and is associated with a permanent device identifier. The system further includes a master device including a communications module operable to address a first communication to a selected slave device using the permanent device identifier associated with the selected slave device, wherein the first communication includes a local identifier assigned to the selected slave device, the assigned local identifier does not match any other local identifier assigned to any other slave device implanted in the human body, and subsequent communications are addressed to the selected slave device using the assigned local identifier.

Abstract: There is provided a method for improving contrast and resolution of an optical image of an object obtained by time-resolved techniques such as Time Domain (TD) and Frequency Domain (FD). The method comprises obtaining a Temporal Point Spread Function (TPSF), and determining optical properties of volumes of interest (VOI), each volume being defined by an ensemble of equiprobable effective photon paths corresponding to a time point or time gate of the TPSF.

Abstract: An optical technique to improve the imaging of a target inside suspensions of scattering particles includes the illumination of the scattering particles with circularly polarized light. The backscattered light from the host medium preserves the helicity of incident light, while the backscattered light reflected from the target is predominated with light of opposite helicity. Based on the observed helicity difference in the emerging light that originated at the target and that backscattered from the medium, the present optical technique improves the image contrast using circular polarization. This approach makes use of polarization memory which leads to the reflected light from the target accompanied by weak diffusive backscattered light. Using the present technique, improved imaging of the artery wall is achieved and plaque composition can be assessed through a blood field associated with the artery.

Abstract: A system and method are provided for estimating blood oxygen saturation independent of optical sensor encapsulation due to placement in blood, where the blood includes a blood flow characteristic of: a relatively low, a stasis, a stagnant value. The method includes determining tissue overgrowth correction factor that includes optical properties of the tissue that cause scattering of the emitted light to a detector and relative amplitudes of the emitted light wavelengths. A corrected time interval measured for infrared light is based on an infrared signal and a corrected time interval for red light is determined by subtracting red light signal due to presence of tissue overgrowth. The red light signal due to tissue overgrowth is proportional to total infrared signal less nominal infrared signal. Oxygen saturation is estimated based on standard calibration factors and the ratio of the corrected infrared time interval and the corrected red time interval.

Abstract: A tube-like reflector insert for a sensor is located in a rigid, light-absorbing sleeve that is closed on one side, and forms a two-part reflector body with the sleeve. A nut is glued onto the open side of the sleeve to enclose the reflector insert. The intravasal part of the sensor is guided in a protective tube having connector threads glued on on both sides. This protective tube is screwed onto the Y connector piece and the reflector sleeve with the nuts. The tip of the sensor is inserted with slight play into the sensor cavity of the reflector insert. The play ensures that sterilization gas can reach all of the intravasal surfaces. The reflector is attached to the sensor via a screw connection outside of the intravasal region, which ensures that the intravasal sensor part is not exposed to clamping stress. Free access for sterilization gas is possible at all intravasal surfaces of the sensor.

Abstract: A system and method are provided for accurately estimating blood oxygen saturation independent of tissue encapsulation of the optical sensor. The method includes determining a tissue overgrowth correction factor that accounts for the optical properties of the tissue that cause scattering of the emitted light to a light detector and the relative amplitudes of the emitted light wavelengths. A corrected time interval measured for infrared light is based on an infrared signal returned from fluid with no tissue overgrowth. A corrected time interval for red light is determined by subtracting a red light signal attributed to the presence of tissue overgrowth. The amount of red light signal attributed to the presence of tissue overgrowth is proportional to the total infrared signal less the nominal infrared signal. Oxygen saturation is estimated based on standard calibration factors and the ratio of the corrected infrared time interval and the corrected red time interval.

Abstract: An implantable medical device comprises a housing having a proximal end and a distal end and a longitudinal axis. A first set of anchoring members are operatively connected to the proximal end of the housing. A second set of anchoring members are operatively connected to the distal end of the housing. The first set of anchoring members and the second set of anchoring members are movable between a collapsed position and a deployed position. The collapsed position is defined as a position whereby the first set of anchoring members and the second set of anchoring members are substantially parallel to the longitudinal axis of the housing. The deployed position is defined as a position whereby the first set of anchoring members and the second set of anchoring members are substantially perpendicular to the longitudinal axis of the housing.

Abstract: A method for implanting a medical device between tissue comprises the steps of providing a catheter having a body and a distal end thereof wherein the catheter includes an implantable device comprising a housing having a proximal end and a distal end and a longitudinal axis. The implantable device further includes a first set of anchoring members operatively connected to the proximal end of the housing and a second set of anchoring members operatively connected to the distal end of the housing. Both sets of anchoring members are movable between a collapsed position and a deployed position. Each set of anchoring members includes ring members connected to a housing of the device. Further steps of the method include inserting the distal end of the catheter into tissue and disposing the medical device at least partially from the distal end of the catheter.

Abstract: Methods are provided for in vivo detection of diseased tissue in a subject, such as tumor tissue located in a body opening, by administering to the subject a biologically compatible fluorescing targeting construct that binds to or is specifically taken up by the diseased tissue. The observer directly views fluorescence emanating from the fluorescing targeting construct bound to or taken up by the diseased tissue upon irradiation of the targeting construct with excitation light having at least one wavelength in the range from 401 nm to about 495 nm, but preferably lacking light having a wavelength above about 500 nm, so as to determine the location and/or surface area of the diseased tissue in the subject. Since excitation wavelength does not penetrate through tissue, as is the practice in near IR diagnostics, the diseased or abnormal tissue is exposed to the excitation light either surgically or by means of an endoscopic device.

Abstract: Disclosed is an access catheter for identifying and providing access through a tissue structure such as the fossa ovalis on the intraatrial septum. The access catheter comprises an elongate flexible tubular body having a proximal and a distal end, and a retractable piercing structure such as a needle carried by the distal end. A detector such as a red, green, and blue light detector is associated with the access catheter, such that placement of the distal end of the catheter against the fossa ovalis can be detected. The piercing structure is thereafter advanceable to provide access to the left atrium through the fossa ovalis.

Abstract: An oversampling pulse oximeter includes an analog to digital converter with a sampling rate sufficient to take multiple samples per source cycle. In one embodiment, a pulse oximeter (100) includes two mor more light sources (102) driven by light source drives (104) in response to drive signals from a digital signal processing unit (116). The source drives (104) may drive the sources (102) to produce a frequency division multiplex signal. The optical signals transmitted by the light sources (102) are transmitted through a patient's appendage (103) and impinge on a detector (106). The detector (106) provides an analog current signal representative of the received optical signals. An amplifier circuit (110) converts the analog current signal to an analog voltage signal in addition to performing a number of other functions. The amplifier circuit (110) outputs an analog voltage signal which is representative of the optical signals from the sources (102).