Apparatus for use in dialyzing a patient, the apparatus comprising: a hemodialysis catheter comprising: an elongated body having a proximal end and a distal end, wherein the distal end terminates in a substantially planar distal end surface; first and second lumens extending from the proximal end of the elongated body to the distal end of the elongated body, wherein the first and second lumens terminate on the substantially planar distal end surface in first and second mouths, respectively, arranged in side-by-side configuration, and further wherein the first and second lumens are separated by a septum; and first and second longitudinal slots formed in the distal end of the elongated body and communicating with the interiors of the first and second lumens, respectively, the first and second longitudinal slots opening on the substantially planar distal end surface; wherein the first and second longitudinal slots each has a length and a width, relative to the dimensions of the first and second lumens and the rate of blood flow to be passed through the hemodialysis catheter, such that (i) when a given lumen is to be used for a return function, the primary blood flow will exit the mouth of that lumen, and (ii) when a given lumen is to be used for a suction function, the primary blood flow will enter the proximal end of the longitudinal slot associated with that lumen, whereby to minimize undesirable recirculation of dialyzed blood.

A method for determining the force applied to a tip of a medical instrument includes receiving inputs from a medical instrument having at least one elongated actuation element used to manipulate a position of the instrument while in a patient's body. The method also includes applying the inputs to a lumped model of the instrument and determining a force on a tip of the instrument based on both the inputs and the lumped model.

According to aspects of the present disclosure, a system for visualizing a target area may include an elongate shaft. The elongate shaft may include a distal portion, a lumen that extends longitudinally through the distal portion, and an opening at the distal end of the distal portion. The opening may be in communication with the lumen. The system also may include a visualization assembly housed within the distal portion of the elongate shaft. The visualization assembly may include a transducer array having a field of view in which the transducer array transceives sound waves. The field of view of the transducer array may cover at least part of the distal portion of the elongate shaft and the target area to facilitate visualization of the part of the distal portion of the elongate shaft and the target area.

A method for delivering fluid to the brain of a subject using an intraparenchymal catheter, the method comprising the step of inserting the catheter 5 into the brain using a posterior to anterior approach and methods of treating neurodegenerative disorders using this delivery method, as well as methods for delivering fluid to an elongate structure of the brain using an intraparenchymal catheter, the method comprising the step of inserting a catheter into the brain along an insertion axis that is substantially aligned with a long axis of the elongate structure.

An intravascular sensor delivery device for measuring a physiological parameter of a patient, such as blood pressure, within a vascular structure or passage. In some embodiments, the device can be used to measure the pressure gradient across a stenotic lesion or heart valve. For example, such a device may be used to measure fractional flow reserve (FFR) across a stenotic lesion in order to assess the severity of the lesion. The sensor delivery device has a distal sleeve configured to pass or slide over a standard medical guidewire. Some distance back from the sensor and distal sleeve, the device separates from the guidewire to permit independent control of the sensor delivery device and the guidewire. The sensor delivery device can be sized to pass over different sizes of guidewires to enable usage in coronary and peripheral arteries, for example.

An electrophysiologic catheter with a distal electrode assembly carrying very closely-spaced bipole microelectrodes on a plurality of divergent spines that can flexibly spread over tissue surface area minimized detection of undesirable noise, including far-field signals. Each spine has a flexible microelectrode panel having a substrate, at least one pair of microelectrodes, a trace for each microelectrode, and a soldering pad. Adjacent microelectrodes of a bipole pair are separated by a space gap distance ranging between about 50-300 microns. Each microelectrode may have a width of about 200 or 300 microns.

A catheter device to visually identify a blood vessel may include a cannula. The cannula may include a distal tip, an elongated tubular shaft, and an inner lumen formed by the elongated tubular shaft. The cannula may also include an optical fiber, which may be disposed within the inner lumen of the cannula. The optical fiber may include a distal end and a proximal end. The optical fiber may be configured to emit light from the distal end.

A fluid dispensing catheter including an elongate body having a proximal portion and a distal portion and defining a passage between the proximal and distal portions, and a plug having a proximal section positioned within the passage in the distal portion of the elongate body to partially occlude the passage, the plug being substantially cylindrical and having a flat parallel to and offset from a longitudinal axis of the plug, the flat defining a gap with the elongate body.

An introducer used to provide a route through which a catheter or other medical device is inserted so as to gain access to a subcutaneous vessel of a patient is disclosed. The introducer is configured so as to minimize the amount of force needed to enter and dilate a vessel, thus reducing trauma to the vessel and the patient. In one embodiment, an introducer is disclosed, comprising a sheath and a dilator. The sheath includes a tubular portion that defines a lumen. The dilator includes an elongate body and a tapered distal tip and is configured to be removably disposed within the lumen of the tubular portion of the sheath. The dilator elongate body defines a cylindrical recess proximally extending from the tapered distal tip. The cylindrical recess configured to receive therein the tubular portion of the sheath when the dilator is disposed within the tubular portion of the sheath.

A catheter assembly for navigation including a flexible catheter having a proximal portion adjacent a proximal end and a distal portion adjacent a distal end and defining a longitudinal axis, the flexible catheter defining a lumen extending therethrough along a longitudinal axis and configured to enable translation of an instrument from the proximal end to the distal end. The flexible catheter defines a compound curve formed on the distal portion, wherein the compound curve includes an elbow bend and a radially curved portion. The elbow bend deflecting the distal portion of the flexible catheter from the longitudinal axis, while the radially curved portion extends from the elbow bend farther deflecting the distal portion about a center point. The catheter guide assembly for navigation includes a control handle disposed at the proximal end of the flexible catheter and is configured to advance and rotate the flexible catheter within a luminal structure.