Abstract:
A method for scaling the impedance measured during the course of an electrophysiology study accounts for impedance drifts. By scaling the impedance there is greater assurance that previously recorded positional information can be used to accurately relocate an electrode at a prior visited position. The scale factor may be based upon a mean value across several sensing electrodes. Alternatively, the scale factor may be calculated specifically with respect to an orientation of a dipole pair of driven electrodes.
Abstract:
A system and method are provided for determining characteristics of a device electrode disposed on a medical device within a body. A plurality of measurement electrodes are coupled to an external surface of the body and establish transmission paths for current through the body. An electronic control unit (ECU) is configured to cause transmission of current between a pair of active electrodes selected from the measurement electrodes and thereby generate a voltage on the device electrode. The ECU receives impedance signals from a plurality of passive electrodes among the measurement electrodes other than the active electrodes. The ECU establishes a virtual reference electrode at a reference position within the body responsive to the impedance signals and computes a position of the device responsive to the voltage on the device electrode and the reference position of the reference electrode. The ECU may also compute impedances at the device and measurement electrodes.
Abstract:
The present invention provides a differential pressure body suit with external support against body suit migration. In its preferred embodiment, such body suit may comprise a close-fitting, multi-layered suit sealed against a mammal's skin to contain the differential pressure, or a looser-fitting suit that bends at the mammal's joints with minimal force. External support means include either fixed or movable mechanical supports attached to the body suit, extraordinary air pressure levels for making the body suit rigid, or exoskeletons attached to the body suit. A cyclic control system can turn the differential pressure condition within the body suit on and off on a selective basis to accommodate the movement of the legs of the mammal.
Abstract:
A method of navigating a medical device through a body of a patient includes providing a topography of at least a portion of the body, accepting user input defining a navigation path, robotically navigating the medical device to a starting point on the path, and robotically navigating the medical device along the navigation path to an endpoint. Waypoints defining the navigation path may be input on a graphical representation of the topography using a user interface such as a pointing device or touchscreen. The navigation path may also be defined by tracing a substantially continuous path on the graphical representation. A therapy may be administered while robotically navigating the medical device along the navigation path, either forward or in reverse, or while navigating the medical device along a return path defined by a plurality of virtual breadcrumbs generated as the medical device traverses the navigation path.
Abstract:
A system for determining a position of a medical device within a body is provided that reduces positional error by establishing a reference origin closer to the device and/or simplifies the system by integrating components and functions. In one embodiment, a pair of drive electrodes are affixed to opposed surfaces of the body and create a pathway for transmission of current through a position sensor related to the medical device. A pair of reference electrodes proximate the drive electrodes are coupled to a common reference node outputting a reference signal establishing the reference origin. An electronic control unit determines the position of the medical device responsive to the position signal and the reference signal. In another embodiment, a patch affixed to an external surface of the body has a base layer and multiple devices supported on the base layer, electrically isolated from one another, and configured to perform different functions.
Abstract:
A robotic catheter rotatable device cartridge may include a housing member attachable to a drive mechanism for rotating the cartridge and a catheter attached to the cartridge along an axial direction of the catheter. A slider block may be generally slidable relative to the housing and engaged with one or more steering wires for controlling movement of the catheter in a transverse direction relative to the axial direction. The catheter may include the steering wire(s) engaged therewith and movable in the transverse direction when the slider block is linearly driven in a predetermined direction.
Abstract:
An apparatus for determining a length of a portion of a steering wire disposed within a bendable medical device includes an electrical contact slidably coupled with a steering wire, an electrical source configured to transmit an electrical signal through a portion of the steering wire, and a processor configured to monitor a parameter of the electrical signal at or about the electrical contact and configured to determine a length of a portion of the steering wire using the monitored parameter.
Abstract:
A method of generating a three-dimensional model of at least a portion of a heart includes inserting an electrode within the portion of a heart, robotically moving the electrode therein, periodically detecting position information of the electrode to generate a plurality of location points defining a space occupied by the portion of the heart, and generating a three-dimensional model of the portion of the heart including position information for at least some of the plurality of location points within the portion of the heart. The plurality of location points includes at least some location points on the surface of the heart and at least some location points interior thereto. The model is generated by utilizing a surface construction algorithm such as a shrink-wrap algorithm to identify the surface points and isolate or eliminate the interior points.
Abstract:
A system for mapping a tissue surface includes a probe for mapping a tissue surface, a localization system to measure a location data point indicative of the probe's location, a memory in which to store the location data point, a servo mechanism to move the probe along at least a portion of the tissue surface, a controller to move the probe to a plurality of locations and to record in the memory a plurality of location data points, and a contact-sensing processor to analyze the plurality of location data points and to identify a subset thereof on the tissue surface. A modeling processor generates a model of the tissue surface using the subset of location data points. The contact-sensing processor utilizes probe velocity, or a rate of change in the distance moved by the probe, to determine contact between the probe and the tissue surface.
Abstract:
A method for scaling the impedance measured during the course of an electrophysiology study accounts for impedance drifts. By scaling the impedance there is greater assurance that previously recorded positional information can be used to accurately relocate an electrode at a prior visited position. The scale factor may be based upon a mean value across several sensing electrodes. Alternatively, the scale factor may be calculated specifically with respect to an orientation of a dipole pair of driven electrodes.