Medical delivery devices, such as catheters, and their methods of use and manufacture. The medical delivery devices are adapted to facilitate the delivery of an agent into a patient. The medical delivery devices may have one or more deformable lumens, each of which has a collapsed configuration and an open configuration. The medical delivery devices may include one or more agent delivery ports, any one of which may be proximal or distal to an expandable device, such as a balloon.

Examples of catheter devices, removable needle devices and kits are disclosed. Also methods for accessing a hollow organ are disclosed. The catheter devices include a body extending longitudinally from a proximal end to a distal end, wherein the body includes an elongated channel along a longitudinal length of the body extending from the proximal end to the distal end of the body, wherein the elongated channel is configured to receive an elongated needle of the removable needle device, and the body includes one or more cutting edges extending in a proximal direction from the distal end of the body. The body of the catheter devices includes one or more recesses adapted to mate with one or more catches of the removable needle device for coupling the needle device to the catheter device. Methods of using the catheters, removable needle devices and the kits are also disclosed.

A guidewire introducible into a bodily lumen having an obstruction therein is provided. An introducer needle is advanced through tissue and into the bodily lumen. A guidewire is advanced through the introducer and into the lumen. The guidewire is advanced further through the lumen until an atraumatic distal tip of the guidewire encounters an obstruction the distal tip cannot pass in a straight forward manner. The distal tip is pressed against the obstruction such that a flexible segment proximal of the distal tip forms a loop distal of the distal tip. The guidewire is advanced further through the lumen such that the loop of the flexible segment is pushed past the obstruction and the distal tip is pulled distally past the obstruction. A greater diameter guidewire extension can be coupled to the back end of the guidewire, providing function as a larger diameter guidewire.

Guidewires useful for cooperating with catheters may be actively steered and/or provide adjustable stiffness. Angle or curvature of a guidewire, and/or flexural modulus of a guidewire, may be adjusted at one or more locations between ends thereof. Variable stiffness segments may include electrically operated compressible and/or extensible materials. Multiple tensile elements may terminate at different body elements to adjust angle or curvature at multiple locations. Multiple circumferentially and/or radially contractible fiber regions may be provided and distributed over a length of a guidewire. Adjustable flexure elements arranged in or along a guidewire may be electrically operated. A flexible core member may be centrally arranged in a tubular body. A flexible guide wire or track may cooperate with electrically operable motor units.

Guidewires useful for cooperating with catheters may be actively steered and/or provide adjustable stiffness. Angle or curvature of a guidewire, and/or flexural modulus of a guidewire, may be adjusted at one or more locations between ends thereof. Variable stiffness segments may include electrically operated compressible and/or extensible materials. Multiple tensile elements may terminate at different body elements to adjust angle or curvature at multiple locations. Multiple circumferentially and/or radially contractible fiber regions may be provided and distributed over a length of a guidewire. Adjustable flexure elements arranged in or along a guidewire may be electrically operated. A flexible core member may be centrally arranged in a tubular body. A flexible guide wire or track may cooperate with electrically operable motor units.

A guide wire gripping device is provided that includes: a sheath; an advanceable and retractable part extending along the longitudinal axis of the sheath; an operation control that moves the advanceable and retractable part along the longitudinal axis; a grasping portion having a contact surface having a peripheral edge surrounded by a distal end, a proximal end, and a pair of side ends; and a support part connected to the advanceable and retractable part and fixed to one of the pair of side ends.

Disclosed catheter insertion systems enable the user to identify the location of the needle based on the electrical properties of subcutaneous tissue relative the electrical properties of other fluids such as blood or air. Disclosed systems can include one or more of the following features: 1) the catheter assembly is modular (e.g., the catheter can be connected and disconnected from the detection unit at will); 2) the detection unit employs an electrical circuit that allows for the discernment between subcutaneous tissue and blood; 3) the system assists the end user with catheter advancement. Some embodiments can be used to insert catheters into a spaces where the needle passes first through subcutaneous fat and muscle before entering fluid or air.

In various aspects, the present disclosure pertains to methods of treating or preventing bleeding at a tissue site comprising applying a chitosan powder composition to the tissue site. In various aspects, the present disclosure pertains to chitosan powder compositions for application to a tissue site, where the powder compositions comprise a chitosan salt, a crosslinked chitosan, a derivatized chitosan, or a combination thereof. In various aspects, the disclosure pertains to catheter assemblies, which are preloaded with a chitosan powder composition and which are configured to deliver the chitosan powder composition a tissue site.

The disclosed image acquisition medical device and medical system make it possible to easily grasp an orientation of a distal end portion of the medical device based on an angiographic image and a tomographic image. The image acquisition medical device includes a flexible body portion that extends in an axial direction; an image sensor that is disposed in the body portion and that is configured to acquire an image of a hollow organ; and a contrast unit that protrudes toward a distal end side of the body portion and that makes an orientation of a distal end portion of the body portion visually recognizable in an angiographic image. Relative positions of the image sensor and the contrast unit in an axial rotation direction are fixed.

A guide wire of the present disclosure includes a core shaft having a distal end portion decreasing in cross-sectional area, a coil body wound to cover the distal end portion, and a distal end fixing portion fixing the core shaft and the coil body to each other. The distal end portion includes a small cross-sectional area portion, a large cross-sectional area portion, and a tapered portion between the small cross-sectional area portion and the large cross-sectional area portion. The core shaft and the coil body are fixed at a portion excluding the tapered portion. A first bending rigidity FR1 of the large cross-sectional area portion, a second bending rigidity FR2 of the small cross-sectional area portion, and a length L of the tapered portion satisfy the following expressions (1) and (2). In the following expressions (1) and (2), the unit of L is mm (millimeter).
(FR1/FR2).sup.0.25/L≥0.83  (1)
1≤L≤3  (2)