The present invention relates to a catheter assembly suitable for computer tomography (CT) scanning and to fluid supply apparatus for such a catheter assembly.
In some CT scan procedures it is desirable to enhance the scanned images of a patient for diagnostic purposes. Enhanced CT scans of this type are typically achieved by injecting into the patient, at the site to be scanned, a contrast agent or dye, which in some instances is iodine based. The injection of such a contrast agent is usually achieved by means of a catheter inserted intraluminally into the patient. The catheter typically is provided with a plurality of lumens extending the entire length of the catheter, one or more of these lumens being used for the supply of the contrast agent, from a source outside the patient, to the distal end of the catheter, which is in use located at the site to be diagnosed. The catheter lumens may also provide for a guide wire for use during insertion of the catheter into the patient and for other known purposes.
For enhanced CT scan procedures, the amount of contrast medium injected and the rate of injection of the medium can often affect the quality of the scan. As a result of this, it is often necessary to inject contrast media through the catheter at a specific flow rate or at least above a minimum specified flow rate.
A problem occurs with existing systems in that the limited diameter of lumen of the catheter provided for the contrast medium limits the rate of flow of contrast media injected therethrough. Increasing the diameter of the lumen is not always possible when multiple lumens are required in the catheter and also when the outer dimensions of the catheter are restricted as a result of the medical application. Increasing the flow pressure can lead to distortion of the catheter as well as possible rupture thereof, of the catheter or failure of one or more of the components of the assembly.
The present invention seeks to provide an improved catheter assembly suitable for computer tomography (CT) scanning and to improved fluid supply apparatus for such a catheter assembly.
According to an aspect of the present invention, there is provided fluid supply apparatus for supplying fluid to a multi-lumen catheter including an inlet element for coupling to a supply of catheter fluid, a plurality of fluid outlet elements and a flow splitter arranged between the inlet element and the outlet elements and able to split or divert flow of fluid from the inlet to at least one of the plurality of outlets.
In practice, the fluid outlet elements are each coupled to one of a plurality of lumens of a catheter. Thus, instead of fluid being supplied to only one of the lumens of the catheter, fluid can be supplied to a plurality of these, and thus through an overall wider cross-sectional luminal area. In some instances, the device can be used to supply fluid through lumens used also for other purposes, such as for a guide wire.
In the preferred embodiment, the flow splitter is configurable so as to adjust the flow to the outlet elements and thus through a catheter attached thereto. For example, the flow splitter may be settable to direct fluid to only one of the outlet elements or to both. In this example, the flow splitter in one embodiment includes an adjustable fluid gate or flap therewithin.
In some embodiments, the flow splitter may include a nozzle for controlling fluid pressure into the outlet elements and thereby into the catheter lumen or lumens.
There may be provided a flow diffuser in one or more of the fluid outlet elements.
According to another aspect of the present invention, there is provided a catheter assembly including a multi-lumen catheter and fluid supply apparatus for supplying fluid to said multi-lumen catheter, the fluid supply apparatus including an inlet element for coupling to a supply of catheter fluid, a plurality of fluid outlet elements arranged to be each coupled to a respective lumen of the catheter and a flow splitter arranged between the inlet element and the outlet elements and able to split or divert flow of fluid from the inlet to at least one of the plurality of outlets.
Embodiments of the present invention are described below, by way of example only, with reference to the accompanying drawings, in which:
Referring to
The catheter assembly 10 of
The assembly 10 also includes a flow splitter or diverter unit 22 (hereinafter referred to as a flow splitter unit) for supplying fluid, such as contrast media, to the feed tubes 18, 20 and thus to a plurality of the lumens of the catheter 12.
The flow splitter unit 22 includes a splitter 24, described in further detail below, first and second fluid feed outlet tubes 26, 28, each coupled in fluid-tight manner to a respective one of the feed tubes 18, 20 of the catheter 16. A coiled extension tube 30 is coupled to the inlet of the splitter 24 and, at its proximal end, to a pressure injection unit 32, of any suitable nature known in the art, for supplying fluid to the assembly 12, 22. In this example, the injector 32 is filled with a contrast medium of any suitable type for enhancing CT scanning.
Referring now to
Referring now to
The ability to control the flow into the tubes 26, 28 and thus into the lumens 118, 120 of the catheter can provide several advantages, including increased flow rate when fluid is fed to both lumens and differential stiffening/deflection of the catheter by feeding fluid to one of the lumens 118, 120, to assist for example in positioning or trackability of the catheter during deployment. Flow through a single lumen 118,120 may also be desired when lower flow rates are required for a particular diagnostic procedure.
Referring now to
Although
The features of the gate 126 of