Disclosed herein are embodiments of segmented metallic guidewires that are suitable for MRI catheterization. Disclosed guidewires comprise a plurality of short conductive metallic segments that individually are short enough such that they do not resonate during MRI. The conductive segments are electrically insulated from each other and mechanically coupled together end-to-end via connectors, such as stiffness matched connectors, to provide a sufficiently long, strong, and flexible guidewire for catheterization that is non-resonant during MRI.

A contour of a cross-section perpendicular to a longitudinal direction of a wire 2 is a circle having a diameter of D. An imaginary circle 4 which is concentric with the circle of the contour of the wire 2 and has a diameter that is of the diameter D, is assumed. On the imaginary circle 4, a first measurement point M1, a second measurement point M2, a third measurement point M3, a fourth measurement point M4, a fifth measurement point M5, a sixth measurement point M6, a seventh measurement point M7, and an eighth measurement point M8 are assumed. A Vickers hardness (Hv) is measured at each of the eight measurement points. A standard deviation of the eight measurement values is not greater than 10. The average of the eight measurement values is preferably not less than 670 and preferably not greater than 770.

The present disclosure relates to core-wire joints for micro-fabricated medical devices, such as guidewires. A hybrid guidewire device includes a core (102) having a joint (105) between a proximal section (110) and a distal section (112) of the core and a tube structure (104) surrounding the joint. The proximal section of the core is made of or includes stainless steel and the distal section is made of or includes a superelastic material such as nitinol. Further, the terminal, distal portion of the proximal section of the core includes serrations (116), and a terminal, proximal portion of the distal section of the core includes complementary serrations (118) sized and shaped to interlock with serrations (116). The distal end of the proximal section mechanically interlocks with a proximal end the distal section to form the joint.

A guide wire-catheter assembly includes a catheter tube having a longitudinal channel, and a guide wire configured to be movable in the longitudinal channel. The catheter tube includes a bendable part near its distal end. The bendable part includes, in the circumferential direction of the catheter tube, a varying flexibility, such that exerting a longitudinal compression force in a proximal direction at a compression location distally of the distal end part results in bending of the bendable part. The guide wire includes an expandable part, where the expandable part is movable between a non-expanded position, in which a cross section of the expandable part is smaller than a smallest cross section of the longitudinal channel of the catheter tube and an expanded position. When the expandable part is in the non-expanded position, the guide wire can be moved completely in and out of the longitudinal channel of the catheter tube.

An access needle includes a hollow shaft having a lumen sized and shaped to slidably receive a guidewire therein and having a distal end including an angled surface extending proximally and transversely from a sharpened distal-most tip of the shaft to a beveled smoothed area of the shaft proximal and transverse to the sharpened tip. The beveled smoothed area is positioned to slidably engage a guidewire extended distally out the distal end of the needle so that, as the guidewire is retracted proximally into the needle, the beveled smoothed area slidably engages the guidewire to minimize abrasion to the guidewire.

The disclosure relates to methods of imaging a portion of a body vessel using magnetic resonance imaging (MRI), methods of performing interventional medical treatment under MRI, interventional medical devices, such as wire guides, useful in performing treatment under MRI, and methods of making interventional medical devices. A method of imaging a portion of a body vessel of a patient using MRI includes advancing through a body vessel an end of a wire guide comprising a continuous metal core member and a continuous jacket disposed over the entire core member through a body vessel and scanning the portion of the patient that is positioned within an MRI scanner and that includes a portion of the body vessel within which the end of the wire guide is disposed. A secondary medical device, such as a catheter, can be disposed over the wire guide and manipulated in the method.

The present disclosure relates to guidewire devices having shapeable tips and effective torquability. A guidewire device includes a core having a proximal section and a tapered distal section. A tube structure is coupled to the core such that the tapered distal section of the core extends into and distally beyond the tube structure. The portion of the core extending distally beyond the tube forms a shapeable tip. One or more coils also extend distally beyond the tube. The tip is configured to reduce the tendency of resilient forces from the tube structure to disrupt a customized shape of the tip.

In a medical guide wire having a connecting structure formed by three members: a tubular connector; a first core; and a second core, when a torsional rigidity of one member is lower than the torsional rigidity of the materials of both end portions, for example, the twist is unevenly generated between the members and the rotation transmission performance to the distal end side is significantly reduced. In such a case, there is a technical problem for improving the rotation transmission performance to the distal end side. In the connecting structure formed by three members, as a result of focusing on the torsional rigidity of the three members and considering the torsional rigidity ratios between the members, the technical problem for improving the rotation transmission performance to the distal end side can be solved when the torsional rigidity ratios satisfy a predetermined relation.

The disclosure provides a system and method for a programmable medical wire that can be preprogrammed, and controlled and reshaped upon command. The system can include a power supply, a controller, and a multilayered wire assembly. The wire assembly includes a core conductor, actuator conductors coupled to the core conductor, selective conductors formed adjacent the core conductor and the actuator conductors, and a protective biocompatible shield around the layers. The selective conductors can be energized to activate the actuator conductors and cause the actuator conductors to bend or twist in a preprogrammed manner. By selectively controlling the direction of movement of the actuator conductors, the wire assembly can be remotely guided through body passageways to the target. Auxiliary equipment such as sensors, micro cameras, detectors, cutters, and other equipment can also be coupled to the wire assembly, and controlled and communicated with through one or more of the selective conductors.

The present disclosure relates to guidewire devices having shapeable tips and effective torquability. A guidewire device includes a core having a proximal section and a tapered distal section. A tube structure is coupled to the core such that the tapered distal section of the core extends into and distally beyond the tube structure. The portion of the core extending distally beyond the tube forms a shapeable tip. One or more coils also extend distally beyond the tube. The tip is configured to reduce the tendency of resilient forces from the tube structure to disrupt a customized shape of the tip.