55 results about "Artery walls" patented technology

Methods and apparatuses for positioning medical devices onto (or close to) a desired portion of the interior wall of an internal channel, such as for scan imaging, for photodynamic therapy and/or for optical temperature measurement. In one embodiment, a catheter assembly has a distal portion that can be changed from a configuration suitable for traversing the internal channel to another configuration suitable for scan at least a spiral section of the interior wall of an internal channel, such as an artery. In one example, the distal portion spirals into gentle contact with (or close to) a spiral section of the artery wall for Optical Coherence Tomography (OCT) scanning. The spiral radius may be changed through the use of a guidewire, a tendon, a spiral balloon, a tube, or other ways.

The present invention is an atherectomy catheter with a hollow head. The head has a window with at least one internal bladed edge, a plunger, and an adjustable angle nose. The angle of the nose can be manipulated by the operator to apply pressure to an artery wall, thereby forcing the window and the window cutting edge up against a plaque target on the opposite side of the artery wall. The position of the plunger can be manipulated by the operator to open or close the window, thereby exposing or not exposing the bladed window edge, and optionally also pinching off dangling plaque fragments. Cut plaque enters the hollow catheter head through the open window, and is stored inside the catheter for removal from the body and subsequent analysis. In some embodiments, the catheter head may have optional sensors, or the plunger may also serve as a rotary cutter.

A method and apparatus for automatically detecting stent struts in an image is disclosed whereby the inner boundary, or lumen, of an artery wall is first detected automatically and intensity profiles along rays in the image are determined. In one embodiment, detection of the lumen boundary may be accomplished, for example, by evolving a geometric shape, such as an ellipse, using a region-based algorithm technique, a geodesic boundary-based algorithm technique or a combination of the two techniques. Once the lumen boundary has been determined, in another embodiment, the stent struts are detected using a ray shooting algorithm whereby a ray is projected outward in the OCT image starting from the position in the image of the OCT sensor. The intensities of the pixels along the ray are used to detect the presence of a stent strut in the image.

Device for carrying out and monitoring an atherectomy, with which a cutting knife driven in a rotating manner by an external unit and set back to project into an opening in the tip of the catheter can be pressed onto the artery wall by means of an inflatable balloon arranged on the side of the catheter casing opposite the window opening, an atherectomy catheter being connected to an OCT catheter to form an integrated unit.

An artery blockage removal system including a hollow plastic tube with IR optical fibers extending longitudinally between its inner and outer walls, the end of the tube having a metal clad tip ring preferably of gold abutting against the end of the IR optical fibers, and the outer surface of the hollow plastic tube having curved arterial guards molded into its outer circumference to hold the inner walls of the artery away from the hollow plastic tube and metal clad tip ring to avoid physical and thermal damage to the inner artery walls, whereby arterial blockage is removed through application of the metal clad tip ring heated by the IR optical fibers and a vacuum applied through the center of the hollow tubing.

An apparatus and method for determining the apparent intima-media thickness (IMT) of arteries through acquisition and analysis of ultrasound images comprising an array of pixel intensities. A datum, or datums, may be established across multiple columns of pixels bounding the portion of the image containing either the lumen/intima boundary, the media/adventitia boundary, or both. The datums may be approximate the shape of one more of the lumen, intima, media, and adventitia. Within a bounded portion of the image, a method may search for intensity gradients having characteristics indicating the gradients represent probable locations of the lumen/intima and media/adventitia boundaries. An IMT measurement is calculated based on the location of the lumen/intima and media/adventitia boundaries. An IMT measurement may be adjusted for sloping or tapering of an artery wall.

The present invention relates to systems and methods used in the measurement of arterial tissue. Optical probes in accordance with the invention use optical fibers to deliver and collect light using a sidelooking catheter. Diffused white light and fluorescence scattering is collected and processed to provide for improved artery wall diagnosis.

There is disclosed a miniature blood rheology measurement device and a blood rheology measurement method which are capable of performing measurement of a portion such as a wrist or a fingertip with a high precision and which are simple without requiring measurement of a blood pressure. The method: detects an artery blood flow rate, a pulsatile displacement, an artery diameter, an artery wall thickness, a heartbeat frequency, and a phase difference or an amplitude ratio of the blood flow rate and the pulsatile displacement, which change with elapse of time, by use of a sensor including ultrasonic wave transmitting and receiving elements for transmitting and receiving ultrasonic waves between the surface of a living body and an artery blood flow in the living body; and calculates a blood kinematic viscosity by use of one of the phase difference and the amplitude ratio, the blood vessel diameter, and the heartbeat frequency to obtain an index value of a blood rheology.

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. The scattering from the particles, such as red blood cells, in the blood is reduced due to polarization memory. The present invention can be also applied to other biomedical application, as well as image targets through adverse environmental conditions, such as fog, clouds, smoke, murky water, etc.

The invention relates to an ultrasonic viewing system, for displaying images of an artery using a curved array of transducer elements, comprising means for acquiring (51) of an ultrasonic image sequence and a Doppler color sequence of a segment of artery explored along its longitudinal axis and having walls moving in relation with the cardiac cycle; and comprising processing means for: estimating the velocity and motion amplitude (53, 54, 55) of the artery walls along Doppler color ultrasound scanning lines; estimating the motion amplitude (58) of the artery walls along lines perpendicular to the artery global axis; and further comprising: display means for displaying (60) curves of this last artery wall amplitude on a dedicated display on which the user may have interaction. The invention further relates to an image processing method having steps to be carried out using this system.

The invention relates to an ultrasonic image processing system, for processing images in an image sequence representing a segment of artery explored along its longitudinal axis, said artery segment showing moving walls; this system comprising: acquisition means (21) for acquiring an ultrasonic image sequence of a segment of artery explored along its longitudinal axis and having walls moving in relation with the cardiac cycle; semi-automatic detection means (22) for detecting the artery walls in an image of the sequence; automatic rigid tracking means (23) for tracking the corresponding artery walls in other images of the sequence; evaluation means (24) for evaluating the artery wall motion and distensibility; and viewing means (154) for visualizing images. The invention further relates to an ultrasound examination apparatus having a curved array of transducer elements and coupled to this system, having viewing means to visualize the images.

An aortic artery measuring probe, device and a method of measuring the diameter of the aortic artery are provided. The aortic artery measuring device includes the aortic artery measuring probe and a signal processing module electrically connected to the aortic artery measuring probe. The aortic artery measuring probe includes a flexible substrate and a sensor array disposed thereon, wherein the sensor array includes M×N ultra-wideband sensors. The ultra-wideband sensors is positioned on a subject and the flexible substrate is deformed to a profile conforming to the profile of the subject. The ultra-wideband sensors transmit a radio wave into the subject and then the radio wave is reflected by a tissue interface of the artery wall of the aortic artery to form a reflected signal. The ultra-wideband sensors receive the reflected signal and the signal processing module analyzes the reflected signal to define the diameter of the aortic artery.

A computer 12 of an image processing apparatus 11 acquires ultrasound B-mode images of consecutive frames to estimate a carotid artery wall at a carotid artery minor axis cross section included in an ultrasound B-mode image of a predetermined frame. The computer 12 also uses, as a template image, the ultrasound B-mode image, which includes the estimated carotid artery wall and surrounding tissues of the carotid artery wall and estimates the size of the diameter of the carotid artery wall so as to minimize a margin of error between a transformed template image, which is created by transforming the template image, and the acquired ultrasound B-mode image of each frame, thereby acquiring the time change of the carotid artery wall.