Abstract: A method is provided for establishing contact of a medical device against a tissue surface within a subject body, the method comprising determination of the geometrical configuration of the distal portion of the medical device, and using this together with known control variable information to determine and control the contact force of the distal tip of the medical device against the tissue surface.

Abstract: A method of controlling a remote navigation system that remotely orients the distal end of the medical device in order to navigate a medical device through a body lumen, the method comprising: displaying an exterior image of the body lumen; superimposing an indicator of the current position of the medical device in the body lumen; displaying a plurality of segment labels; receiving oral commands and recognizing one of the spoken displayed segment labels; and causing the remote navigation system to orient the distal end of the device in a preselected direction associated with the segment corresponding to the displayed segment label.

Abstract: A method of applying an electrode on the end of a flexible medical device to the surface of a body structure, the method including navigating the distal end of the device to the surface by orienting the distal end and advancing the device until the tip of the device contacts the surface and the portion of the device proximal to the end prolapses. Alternatively the pressure can be monitored with a pressure sensor, and used as an input in a feed back control to maintain contact pressure within a pre-determined range.

Abstract: A method of controlling a remote navigation system that remotely orients the distal end of the medical device in order to navigate a medical device through a body lumen includes displaying an endoluminal image of the portion of the body lumen through which the device is being navigated, including an image of the distal end of the medical device; displaying a plurality of directional controls associated with the displayed endoluminal image; and accepting inputs of a selected direction of change of orientation of the distal tip from the directional controls and in response operating the remote navigation system to change the direction of orientation of the distal end of the medical device in the selected direction. The distal end of the device may alternatively or additionally be oriented to point toward a point corresponding to a point that the user identifies on the displayed endoluminal image.

Abstract: An electrophysiology catheter includes a tube having a proximal end, a distal end, and a lumen therebetween. The tube is preferably comprised of multiple sections of different flexibility, arranged so that the flexibility of the catheter increases from the proximal end to the distal end. There is a first generally hollow electrode member at the distal end. At least one magnetically responsive element is disposed at least partially in the hollow electrode, for orienting the distal end of the catheter with an externally applied magnetic field. Multiple magnets can be distributed over the distal portion of the device. The end electrode can have openings for delivering irrigating fluid, and/or a sleeve can be provided around the tube to create an annular space for the delivering of irrigating fluid. A temperature sensor can be provided to control the operation of the catheter. A localization coil can also be included to sense the position and orientation of the catheter.

Abstract: A method of placing a pacing lead in the heart includes moving an electrode catheter successively to a plurality of possible placement sites. The viability of the tissue at each site is determined. If the tissue at the site is viable, a pacing signal is applied to the tissue at the site, and the effectiveness of the pacing from the site is measured. After the area has been mapped in this fashion, at least one pacing lead is placed from at least one of the sites which exceeded a predetermined level of pacing effectiveness.

Abstract: A method for determining a transformation of a three-dimensional pre-operative image data set to obtain a registration of the three-dimensional image data with an X-ray imaging system. In one aspect of the present invention, the method comprises the steps of the user identifying a center point and extreme contour points of the object from an X-ray image, obtaining a set of contour points for the image object in each of a plurality of section-planes, and selecting from a sampling of section-planes the points projecting nearest to the user-identified extreme points. The method then defines a grid having a predetermined number of intervals at a predetermined interval spacing with the grid center at the user-identified center of the pre-operative image, and performs a projection of the center point of the three-dimensional image data set onto each grid point for evaluation and selection of the grid point projecting nearest to the user-identified center.

Abstract: A method for obtaining registration of a three-dimensional image data set of an anatomical vessel with corresponding two-dimensional image data of the vessel in an X-ray imaging system, where the method comprise the user identifying two points on an anatomical vessel on at least two X-ray image planes, the user identifying two similar points on the surface of the corresponding three-dimensional anatomical image data, determining the orientation direction of the vessel from the two user identified image data surface points, determining the orientation direction of the vessel from the two points obtained from the X-ray image planes, and calculating a transformation of the three-dimensional image data to obtain a best fit registration of the direction derived from the image surface points with the direction derived from the X-ray image data points.

Abstract: A method for determining a translation of a three-dimensional pre-operative image data set to obtain a registration of the three-dimensional image data with a patient positioned in a projection imaging system. In one embodiment the user identifies an initial three-dimensional organ center from projections and extreme contour landmark points of the object on a set of projections. A set of contour points for the image object in each of a plurality of three-dimensional cross-section planes; is obtained and the points projecting nearest to the user-identified landmark points are selected. A three-dimensional grid having a predetermined number of intervals at a predetermined interval spacing centered at the user-identified organ center is defined. The three-dimensional image data contour points as centered onto each grid point are projected for evaluation and selection of the grid point leading to contour points projecting nearest to the user-identified landmark points.

Abstract: A guide wire for magnetically navigating a medical device through in a subject's body comprising an elongate wire having a proximal and distal end, a portion adjacent the distal end that is more flexible than the more proximal portions of the elongate wire, and a first magnetically responsive element on the distal end of the elongate wire. The guide wire further comprises one or more magnetically responsive elements spaced apart from the first magnetically responsive element and disposed on the more flexible portion of the elongate wire. The guide wire provides for bending or deflecting the distal end of the stent, to provide easier navigation of the distal end of the guide wire and the stent through the vasculature of a subject body.

Abstract: A method for controlling a remote navigation system to navigate a medical device in an operating region in a subject is provided, comprising operating the remote navigation system to bring a sensor carried on a medical device successively into a plurality of locations in a predetermined pattern, and using the sensor to sense a physiological property of the subject in each location. At least once thereafter, the method operates the remote navigation system to bring a sensor carried on a medical device successively into a series of locations in a predetermined pattern relative to at least one location selected from the predetermined pattern in the immediately preceding step based upon the sensed physiological property value, and uses the sensor to sense the physiological property in each location.

Abstract: A method of screening subjects for medical procedures involving the remote navigation of a medical device through the vasculature in an operating region. The method includes processing the image data of the operating region to determine a measure of the complexity of at least a portion of the vasculature in the operating region; and generating a recommendation about at least one parameter of the procedure based at least in part upon a comparison between the determined measure of complexity and a predetermined value.

Abstract: A system for controlling a medical device in a patient. A display system displays an image of a volume of the patient in a virtual three-dimensional space. A stylus is controllable to actuate a virtual element in the virtual space. A navigation system controls the medical device in the patient volume based on a position of the actuated virtual element. This inherently three-dimensional interface allows a physician to actuate the medical device more intuitively than possible using a two-dimensional interface.

Abstract: A control and control method for a remote navigation system including an orientation controller that orients the distal end of a medical device in an operating region in a subject, and a length controller that extends and retracts the distal end of the medical device, to navigate the distal end of the medical device to a selected destination in response to user inputs. In accordance with the control method, the control interrupts operation of at least one of the orientation controller and the length controller when the user inputs would cause the orientation controller and the length controller to navigate the distal end of the medical device to one of a plurality of predetermined restricted locations (or alternatively when the user inputs would cause the orientation controller and length controller to navigate the distal end of the medical device other than to one of a plurality of predetermined target locations).

Abstract: A method of identifying an elongate medical device in a two-dimensional image of an operating region includes filtering pixels meeting a predetermined intensity requirement for linear scaling, dividing the filtered pixels into groups of contiguous pixels, and selecting from the groups a group corresponding to the medical device.

Abstract: The invented guidewire relates to improvements in a magnetically navigable medical guidewire to enable passage through an occluded or partially occluded vessel. The guidewire comprises an elongate wire having a proximal end and a distal end, wherein the distal end further comprises a magnetically responsive element and a helical thread formed on the tip. The distal end of the guidewire may be preferably aligned substantially in the direction of an applied magnetic field, after which the proximal end of the guidewire may be torqued to rotate the threaded tip while remaining aligned with the applied magnetic field and cause the tip to screw through the blockage in the occluded vessel.

Abstract: A system and method are provided for control of a navigation system for deploying a medical device within a subject, and for enhancement of a display image of anatomical features for viewing the projected location and movement of medical devices, and projected locations of a variety of anatomical features and other spatial markers in the operating region. The display of the X-ray imaging system information is augmented in a manner such that a physician can more easily become oriented in three dimensions with the use of a single-plane X-ray display. The projection of points and geometrical shapes within the subject body onto a known imaging plane can be obtained using associated imaging parameters and projective geometry.

Abstract: A method of operating a navigation system that can orient the distal end of a medical device in a selected direction to navigate the medical device through a network of body lumens in an operating region in a subject that includes identifying a path through the network of body lumens in the operating region; displaying a two-dimensional image of the operating region including the path through the body lumens; determining at least one location on the path; and operating the navigation system to orient the distal end of the medical device in a direction substantially aligned with the path at the at least one location and advancing the distal end of the medical device.

Abstract: A system for navigating a medical device through the lumens and cavities in an operating region in a subject, comprising an imaging system for displaying an image of the operating region, including a representation of the distal end of the medical device in the operating region. The system also includes a localization system for determining the position of the medical device in a frame of reference translatable to the displayed image. Finally, the system includes an algorithm for evaluating one or more rotation matrix using a cost function to determine an optimum rotation matrix for performing transformation of a vector in the local frame of the localization system to that of the reference frame of the navigation system. The rotation matrix can then provide a scale invariant transformation or “registration” of the coordinate systems of the localization system and the navigation system.

Abstract: An interface for remotely controlling a medical device in a patient's body provides a two dimensional display of a three dimensional rendering of the operating region, and allows the user to select the orientation or location of the distal end of the medical device on the display and then operate a navigation system to cause the distal end of the medical device to approximately assume the selected orientation or location.