Abstract: A method of detecting whether a localization element is within or outside of an introducer sheath generally includes obtaining a localization signal from the localization element and detecting the state of the localization element relative to the sheath based upon the quadrature component of the localization signal. A baseline quadrature component is typically established with the localization element outside of the sheath. When the quadrature component deviates from this baseline value, it is indicative of the localization element being within the sheath. Conversely, when the quadrature component remains relatively close to the baseline value, it is indicative of the localization element being outside of the sheath. In an electrophysiology study, the state information can be used to take corrective action with respect to the data being collected.

Abstract: A three dimensional physiological mapping system utilizing an intracardiac echo catheter capable of being located in six degrees of freedom by a visualization, navigation, or mapping system. An echocardiography image of the intracardiac echo catheter may be projected within a geometric model of the visualization, navigation, or mapping system where the location of the projected image is adjusted in response to user input identifying a structure present in the echocardiography image and the geometric model.

Abstract: A diagnostic device and method for assessing lesion formation by measuring temperature changes during endocardial ablation. Intracardiac echo catheter data is accurately mapped into a model maintained by a visualization, navigation, or mapping system using the position and orientation of the intracardiac echo catheter transducer within the model. For each point in the model, either a frequency shift or echo time shift is calculated from the intracardiac echo data to determine local temperature changes, and the local temperature changes are displayed within a rendering of the model for the user.

Abstract: A system and method for identifying a location of a physical structure in a body is provided. The system includes an electronic control unit configured to register a first image of a portion of the body in a three-dimensional coordinate system. The electronic control unit is further configured to identify the location of the physical structure in the three-dimensional coordinate system responsive to flow of a fluid shown in the image. The fluid may comprise blood. In one embodiment, the electronic control unit is further configured to generate a second image, such as a three dimensional model, incorporating a representation of the physical structure within a larger physical environment in the three-dimensional coordinate system.

Abstract: A three dimensional physiological mapping system utilizing an intracardiac echo catheter capable of being located in six degrees of freedom by a visualization, navigation, or mapping system. An echocardiography image of the intracardiac echo catheter may be projected within a geometric model of the visualization, navigation, or mapping system where the location of the projected image is adjusted in response to user input identifying a structure present in the echocardiography image and the geometric model.

Abstract: A diagnostic device and method for assessing lesion formation by measuring temperature changes during endocardial ablation. Intracardiac echo catheter data is accurately mapped into a model maintained by a visualization, navigation, or mapping system using the position and orientation of the intracardiac echo catheter transducer within the model. For each point in the model, either a frequency shift or echo time shift is calculated from the intracardiac echo data to determine local temperature changes, and the local temperature changes are displayed within a rendering of the model for the user.

Abstract: A sensing assembly for sensing contact with an object is disclosed. The contact sensing assembly may comprise an elongate tubular body. An electrode may be connected to the elongate tubular body. A vibration element is operatively connected with the electrode and configured to deliver a vibration-inducing signal to induce vibration of the electrode. A sensor is configured to monitor the electrode for a perturbation in the induced vibration. The perturbation results from contact between the electrode and the object.

Abstract: A method of detecting whether a localization element is within or outside of an introducer sheath generally includes obtaining a localization signal from the localization element and detecting the state of the localization element relative to the sheath based upon the quadrature component of the localization signal. A baseline quadrature component is typically established with the localization element outside of the sheath. When the quadrature component deviates from this baseline value, it is indicative of the localization element being within the sheath. Conversely, when the quadrature component remains relatively close to the baseline value, it is indicative of the localization element being outside of the sheath. In an electrophysiology study, the state information can be used to take corrective action with respect to the data being collected.

Abstract: An introducer sheath for a medical device is provided. The sheath includes a deformable, elongate body disposed about a longitudinal axis. The body has proximal and distal ends and defines a lumen extending between the proximal and distal ends and configured to allow passage of the medical device therethrough. The body is configured to allow an electric current to pass radially between a space outside of the body and the lumen such that the position of the medical device within a patient can be monitored and electrogram readings from body tissues can be measured while the device is in the sheath. In some embodiments of the invention, the body may include a one or more apertures extending from the radially outer surface of the body to the lumen or a portion of the body may be made from a conductive and/or fluid permeable material.

Abstract: A catheter includes a handle that advantageously limits the amount of torque that can be imparted to the body of the catheter. This advantageously reduces the likelihood of catheter failure, damage to tissue, or damage to medical devices introduced into the vasculature via the catheter. The catheter handle includes a grip portion that the practitioner manipulates in order to impart a torque and a torque transmitting portion operably coupled thereto that transmits the torque to the catheter body. A torque limiting mechanism decouples the torque transmitting portion from the grip portion, the body, and/or any pull wires when the torque imparted to the grip portion exceeds a torque threshold, thereby preventing excessive torques from being transmitted to the catheter body and/or pull wires. A practitioner may be able to adjust the torque threshold and may be able to disable the torque limiting mechanism.

Abstract: An system and method for displaying a position of a medical device disposed within a region of interest in a body are provided. The system includes a position sensing system disposed outside of the body and configured to interact with a position sensor on the medical device upon generation of an electric and/or magnetic field. The sensor generates a position signal indicative of the position of the device within a coordinate system. The system further includes an electronic control unit comprising a registration module for registering a volumetric data set within the coordinate system. The unit further comprises a generation module for generating a volumetric rendering of the region of interest from the volumetric data set and a superimposition module for superimposing a representation of the medical device on the volumetric rendering responsive to the position signal.

Abstract: An intracardiac imaging system configured to display electrode visualization elements within an intracardiac echocardiography image where the electrode visualization elements represent intracardiac electrodes in close proximity to the plane of the image. The system further allows cross sections of tissue structures embodied in intracardiac echocardiography images to be modeled within a visualization, navigation, or mapping system when automatically segmented to generate shell elements for modifying the modeled tissue structures.

Abstract: A method of displaying the influence of an aspect of a model includes acquiring a two-dimensional echocardiogram having a variable intensity; relating the two-dimensional echocardiogram to a plurality of mapping points, the mapping points existing in a three-dimensional model space; determining a degree of influence value for a mapping point; and displaying the mapping point with a visual attribute that corresponds to the determined degree of influence value.

Abstract: A method of refining an anatomical model includes acquiring a two-dimensional echocardiogram that has a variable intensity, relating the two-dimensional echocardiogram to a plurality of mapping points that exist in three-dimensional space, and determining a confidence value for each of two or more mapping points that corresponds to an intensity at a point on the two-dimensional echocardiogram.

Abstract: An apparatus and method for identifying objects in an ultrasound image that includes acquiring ultrasound information from a catheter, locating the ultrasound information to a three-dimensional cardiac model having two or more distinct anatomic objects, displaying at least one of the distinct anatomic objects from the cardiac model within a visual representation of the ultrasound information, and identifying the at least one of the distinct anatomic objects within the visual representation of the ultrasound information using the identifier provided for that object in the three-dimensional cardiac model.

Abstract: A system and method for identifying a location of a physical structure in a body is provided. The system includes an electronic control unit configured to register a first image of a portion of the body in a three-dimensional coordinate system. The electronic control unit is further configured to identify the location of the physical structure in the three-dimensional coordinate system responsive to flow of a fluid shown in the image. The fluid may comprise blood. In one embodiment, the electronic control unit is further configured to generate a second image, such as a three dimensional model, incorporating a representation of the physical structure within a larger physical environment in the three-dimensional coordinate system.

Abstract: A catheter includes a handle that advantageously limits the amount of torque that can be imparted to the body of the catheter. This advantageously reduces the likelihood of catheter failure, damage to tissue, or damage to medical devices introduced into the vasculature via the catheter. The catheter handle includes a grip portion that the practitioner manipulates in order to impart a torque and a torque transmitting portion operably coupled thereto that transmits the torque to the catheter body. A torque limiting mechanism decouples the torque transmitting portion from the grip portion, the body, and/or any pull wires when the torque imparted to the grip portion exceeds a torque threshold, thereby preventing excessive torques from being transmitted to the catheter body and/or pull wires. A practitioner may be able to adjust the torque threshold and may be able to disable the torque limiting mechanism.

Abstract: A three dimensional physiological mapping system utilizing an intracardiac echo catheter capable of being located in six degrees of freedom by a visualization, navigation, or mapping system. An echocardiography image of the intracardiac echo catheter may be projected within a geometric model of the visualization, navigation, or mapping system where the location of the projected image is adjusted in response to user input identifying a structure present in the echocardiography image and the geometric model.

Abstract: An alloy composition suitable for use as a single crystal seed comprises nickel and, in the proportion of 5 to 50 weight %, a further metal selected from the Transition Series of elements in Period VI of the Periodic Table of Elements. The further metal may be tungsten or tantalum. The alloy composition contains no component which forms an oxide layer at elevated temperatures, and in particular contains no aluminium or titanium. The alloy composition is suitable for use as a seed alloy for the casting of single crystal components such as aerofoils for gas turbine engines.

Abstract: An alloy composition suitable for use as a single crystal seed comprises nickel and, in the proportion of 5 to 50 weight %, a further metal selected from the Transition Series of elements in Period VI of the Periodic Table of Elements. The further metal may be tungsten or tantalum. The alloy composition contains no component which forms an oxide layer at elevated temperatures, and in particular contains no aluminium or titanium. The alloy composition is suitable for use as a seed alloy for the casting of single crystal components such as aerofoils for gas turbine engines.