Abstract: A method to measure spatial fluid flow components and their velocity profiles in a number of locations in a cross-sectional area of a lumen or other body cavity by using ultrasound in which the cross-sectional area is interrogated by a plurality of ultrasonic beams; the estimation of the spatial flow components is obtained from a combination of estimations of axial, lateral and total flow; the estimation of one or more flow components is obtained through any combination of time-shift and decorrelation analysis of two or more beam-signals of the interrogating ultrasound transducer; and the estimation accuracy is further improved by the use of a reference decorrelation curve obtained from experiments or beam-theory or both.

Abstract: A method for forming a balloon for a dilation catheter is provided herein. The method includes the steps of: (i) positioning a tube in a preconditioned mold; (ii) expanding the tube in a preconditioned mold to form a parison; (iii) positioning the parison in a balloon mold; and (iv) expanding the parison within the balloon mold to form the balloon. Thus, the tube is initially expanded into a parison in the preconditioned mold. Subsequently, the parison is expanded into a balloon in the balloon mold. Because of this unique manufacturing process, polyester block copolymers can be formed into balloons. Some of these polyester block copolymers could not be formed into a balloon using prior art blow molding processes. The resulting balloon exhibits superior characteristics, including relatively thin and consistent walls, soft texture, low uninflated crossing profile, expansion in a predictable fashion, and good tensile strength.

Abstract: A delivery device and method for delivering a dosage of radiation from a radiation source to a treatment site of a vessel is provided herein. The delivery device includes a catheter and a delivery area. The catheter is suitable for being inserted into a vessel lumen of the vessel and includes a delivery lumen for receiving the radiation source. The delivery area also receives the radiation source. The delivery area includes an attenuator section for attenuating a portion of the radiation emitting from the radioactive area so that the delivery area emits an eccentric radiation profile. The delivery device can also include a catheter supporter which inhibits rotational deformation in the catheter between a catheter distal end and a catheter proximal end. This allows the delivery area to be precisely rotated to properly position the attenuator section within the vessel lumen.

Abstract: Several methods for fabricating an ultrasound transducer assembly having a flexible circuit are provided. Preferably, the method comprises attaching an ultrasound transducer array and integrated circuitry to the flexible circuit during fabrication of the ultrasound transducer assembly while the flexible circuit is in a:substantially flat shape. The contacts of the transducer elements are positioned on substantially the same plane such that electrical contact with signal and ground lines on the flexible circuit is established without the need for conductive bridges to physically remote electrodes.

Abstract: A signal conditioning device is disclosed that interfaces a variety of sensor devices, such as guide wire-mounted pressure sensors, to physiology monitors. The signal conditioning device includes a processor for controlling sensor excitation and signal conditioning circuitry within the signal conditioning device. The processor also supplies signals to an output stage on the signal conditioning device representative of processed sensor signals received by a sensor interface of the signal conditioning device. Power for the signal conditioning device processor is supplied by an excitation signal received from a physiology monitor that drives the output stage. In addition, a temperature compensating current source provides an adjustment current to at least one of a pair of resistive sensor elements to compensate for differences between temperature change upon the pair of resistive sensor elements, thereby facilitating nullifying temperature effects upon the resistive sensor elements.

Abstract: A catheter (200) includes a spear shaped tip (130). In one embodiment, the spear shaped tip (130) is part of a spear shaped tip assembly (100) that includes a swivel assembly. The swivel assembly provides for improved trackability of the catheter (200) over a guide wire. The spear shaped tip catheter of the present invention can be designed in numerous configurations including over-the-wire and rapid exchange versions.

Abstract: A guide wire having pressure sensing capabilities for measuring the pressure of liquid in a vessel comprising a flexible elongate member and having proximal and distal extremities and having an outside diameter of 0.018″ or less. The distal extremity of said flexible elongate member is adapted to be disposed in the liquid in said vessel. A housing is carried by the flexible elongate member and has a diameter substantially the same as the diameter of the flexible elongate member. The housing has a space therein with a pressure sensor mounted in the space in the housing. The pressure sensor has a diaphragm that is sensitive to changes of pressure in the liquid in the vessel. The diaphragm is rectangular in shape and is bordered by a rim surrounding the well. A backing plate is formed of an insulating material bonded to the crystal and serves to reinforce the rim of the crystal of semiconductor material.

Abstract: A guide wire having pressure sensing capabilities for measuring the pressure of liquid in a vessel comprising a flexible elongate member and having proximal and distal extremities and having an outside diameter of 0.018″ or less. The distal extremity of said flexible elongate member is adapted to be disposed in the liquid in said vessel. A housing is carried by the flexible elongate member and has a diameter substantially the same as the diameter of the flexible elongate member. The housing has a space therein with a pressure sensor mounted in the space in the housing. The pressure sensor has a diaphragm that is sensitive to changes of pressure in the liquid in the vessel. The diaphragm is rectangular in shape and is bordered by a rim surrounding the well. A backing plate is formed of an insulating material bonded to the crystal and serves to reinforce the rim of the crystal of semiconductor material.

Abstract: An ultrasound transducer array (408) includes at least one transducer element (412) having a first (604) and second (606) portions separated by an acoustical discontinuity (520). The first portion (604) has the desired length to form a half-wave k31 resonance, while the second portion (606) has a resonant length for an undesired very low frequency out-of-band k31 resonance. The thickness of the transducer element (412) is designed for k33 half-resonance. Given the design, the transducer element (412) can operate and provide for both forward-looking (514) and side looking (512) elevation apertures. A method is also disclosed for using the disclosed ultrasound transducer (412) in ultrasound imaging.

Abstract: A method for providing intravascular brachytherapy includes the step of positioning a radiation source within a target area to be radiation and orienting the attenuator found on the catheter. Once the attenuator or shield is properly oriented, a reference or normalization point or marker (508) is selected. This reference marker (508) can placed, as one example, on the external elastic lamina closest to catheter (100) and can serve as a reference point for the brachytherapy treatment. Several other points of interest can be is selected (504, 506, 510) on the image (500) or images that have been gathered of the treatment site, with dosage levels (512, 522, 520 and 518) being display automatically on the display (406) close to the IVUS image (500).

Abstract: An ultrasound transducer array (408) includes at least one transducer element (412) having a first (604) and second (606) portions separated by an acoustical discontinuity (520). The first portion (604) has the desired length to form a half-wave k31 resonance, while the second portion (606) has a resonant length for an undesired very low frequency out-of-band k31 resonance. The thickness of the transducer element (412) is designed for k33 half-resonance. Given the design, the transducer element (412) can operate and provide for both forward-looking (514) and side looking (512) elevation apertures. A method is also disclosed for using the disclosed ultrasound transducer (412) in ultrasound imaging.

Abstract: A device and method for precisely delivering dosage of radiation from a radiation source to a treatment site of a vessel is provided herein. In one embodiment, the device includes a catheter which inserts into a vessel lumen of the body. The catheter includes an adjuster section for altering a portion of the radiation emitting radially from the radiation source so that the radiation source delivers an asymmetrical radiation profile to the vessel. The device can also include a catheter supporter which inhibits rotational deformation in the catheter between a catheter distal end and a catheter proximal end. This allows the delivery section to be precisely rotated to properly position the adjuster section within the vessel lumen.