Systems and methods are disclosed herein that generally involve CED devices with various features for reducing or preventing backflow. In some embodiments, CED devices include a tissue-receiving space disposed proximal to a distal fluid outlet. Tissue can be compressed into or pinched/pinned by the tissue-receiving space as the device is inserted into a target region of a patient, thereby forming a seal that reduces or prevents proximal backflow of fluid ejected from the outlet beyond the tissue-receiving space. In some embodiments, CED devices include a bullet-shaped nose proximal to a distal fluid outlet. The bullet-shaped nose forms a good seal with surrounding tissue and helps reduce or prevent backflow of infused fluid.

The present invention provides methods of delivering a composition comprising nanoparticles that comprise a macrolide and an albumin by directly injecting the nanoparticle composition into the blood vessel wall or the tissue surrounding the blood vessel wall. The methods can be used for inhibiting negative remodeling or vascular fibrosis in the blood vessel and are useful for treating various diseases.

This document provides methods and materials for delivering agents to liver tissue. For example, methods and materials for using microbeads to deliver agents (e.g., chemotherapeutic agents) to liver tissue are provided.

Materials and methods of using the same to improve structural integrity of a wall of a mammalian luminal organ. In an exemplary method of method for reinforcing a wall of a luminal organ, the method comprises the steps of inserting at least part of a needle into a blood vessel of a patient, advancing a distal end of the needle within the blood vessel to a location adjacent to a wall of a luminal organ of interest, piercing the wall of the luminal organ using the needle so that a tip of the needle is present within the wall of the luminal organ, injecting a substance through the needle and out of a distal portion of the needle so that at least some of the substance is present outside of the needle and inside of the wall of the luminal organ to reinforce the wall of the luminal organ.

The present disclosure relates to a catheter device comprising a catheter hub in which a valve member is disposed, a needle fixed in a needle hub, the needle extending through the valve member in the catheter hub in a ready position, and a tubular receptacle in which the needle hub is displaceably guided and biased by a spring in a proximal direction relative to the receptacle, wherein the needle hub is releasably held in the ready position in the receptacle against the force of the spring by frictional force between needle circumference and catheter or catheter hub, which frictional force is reduced on retraction of the needle through the catheter hub such that the force of the spring prevails.

Multichannel systems for engaging a bodily tissue and methods of using the same. In at least one embodiment of an exemplary multichannel system for engaging a tissue of the present disclosure, the system comprises an engagement catheter comprising a proximal end, a distal end, and defining a first lumen and second lumen extending between the proximal end and the distal end, an inducer sheath having a proximal portion and a distal portion, and defining a lumen extending therethrough, the inducer sheath configured for insertion into the second lumen of the engagement catheter, and a dilator defining a first channel and a second channel extending therethrough and a tapered tip at the distal end of the dilator, the dilator sized and shaped for inserted into the lumen of the inducer sheath.

The present disclosure relates to a catheter device comprising a catheter hub in which a valve member is disposed, a needle fixed in a needle hub, the needle extending through the valve member in the catheter hub in a ready position, and a tubular receptacle in which the needle hub is displaceably guided and biased by a spring in a proximal direction relative to the receptacle, wherein the needle hub is releasably held in the ready position in the receptacle against the force of the spring by frictional force between needle circumference and catheter or catheter hub, which frictional force is reduced on retraction of the needle through the catheter hub such that the force of the spring prevails.

A safety needle device includes a housing including a passageway with a needle cannula extending therefrom. A shielding member is movable between a first position in which a puncture tip of the needle cannula is exposed therefrom and a second position in which the puncture tip of the needle cannula is encompassed therein. The shielding member is maintained in the first position against a biasing force which biases the shielding member toward the second position. A fluid and/or a temperature activation material is associated with the shielding member and is adapted to deform upon contact with a fluid medium and/or a certain temperature or temperature range. The fluid medium flowing through the needle cannula causes the fluid activation material to deform, such as through expansion, thereby releasing the shielding member from the first position and allowing a drive member to bias the shielding member toward the second position.

A percutaneous catheter system for use within the human body and an ablation catheter for ablating a selected tissue region within the body of a subject. The percutaneous catheter system can include two catheters that are operatively coupled to one another by magnetic coupling through a tissue structure. The ablation catheter can include electrodes positioned within a central portion. The ablation catheter is positioned such that the central portion of a flexible shaft at least partially surrounds the selected tissue region. Each electrode of the ablation catheter can be activated independently to apply ablative energy to the selected tissue region. The ablation catheter can employ high impedance structures to change the current density at specific points. Methods of puncturing through a tissue structure using the percutaneous catheter system are disclosed. Also disclosed are methods for ablating a selected tissue region using the ablation catheter.

An MR compatible injection catheter is provided. The MR compatible injection catheter includes an inner shaft; an outer shaft circumferentially surrounding the inner shaft; and a means for actively tracking the catheter in a patient within a MRI. The means for actively tracking the catheter includes two or more tracking coils in the outer shaft. The inner shaft is configured to move relative to the outer shaft and includes an inner tube circumferentially surrounded by an outer tube.