Patent Description:
Intracerebral hemorrhage (ICH) is a sudden bleeding into brain tissue, which can have devastating results. It is the only major stroke subtype without a clearly effective treatment. ICH occurs in over <NUM>,<NUM> Americans yearly and is fatal in <NUM>-<NUM>% of all occurrences, while leaving the majority of survivors with significant motor and cognitive disabilities.

MISTIE (Minimally Invasive Surgery Plus rt-PA for Intracerebral Hemorrhage Evacuation) is a series of clinical trials conducted by neurosurgeons and neurologists to investigate the efficacy of treating ICH by quickly removing blood from the brain through minimally invasive surgery and intermittent dosing of the clot-busting drug, recombinant tissue plasminogen activator (rt-PA). The premise is that by dissolving and removing the clot faster, injury to the brain will be reduced and the patient's prognosis improved.

MISTIE-II, a phase II set of clinical trials for the same purpose, have shown that a blood clot in the brain, can be successfully removed quickly and safely. These early results also suggest that the MISTIE technique may reduce the rate of death, but more significantly, improves the patient's neurologic functioning and quality of life in the year following the occurrence of ICH.

MISTIE-III is an international, phase III <NUM>-patient clinical trial designed to confirm the preliminary findings in a larger number of patients, and has the primary goal of defining a successful treatment for ICH.

<FIG> illustrates a computed tomography (CT) scan slice of a normal brain <NUM>' that reveals no ICH, whereas <FIG> illustrates a CT scan slice of an abnormal brain <NUM> that reveals an ICH <NUM> residing in a ventricle <NUM> of the brain <NUM>'. The tools used in a MISTIE procedure to treat the ICH <NUM> are simplistic. In general, a conventional external ventricular drain (EVD) catheter <NUM> is placed through a standard burr-hole access <NUM> in the cranium <NUM> into the ventricle <NUM> at the site of the ICH <NUM>, as illustrated in <FIG>. Image guidance may be used Magnetic Resonance (MR)/Computed Tomography (CT), or external anatomical landmarks may be used via standardized methods without image guidance, to target the EVD catheter <NUM> into the ventricle <NUM> (using standard ventricular access routes in the case of an intraventricular hemorrhage) at the site of the ICH <NUM>, although the EVD catheter <NUM> may be targeted to a location outside of the ventricle <NUM> in the case of an extra-ventricular hemorrhage. In either case, Magnetic Resonance MR/CT imaging is used to confirm correct placement at the site of the ICH <NUM>.

Once correct placement of the EVD catheter <NUM> is confirmed, an initial bolus of rt-PA is infused in the ventricle <NUM> at site of the ICH <NUM> via the EVD catheter <NUM>, and allowed to remain in place for approximately <NUM>-<NUM> hours to dissolve the clot, while the EVD catheter <NUM> remains open and may be allowed to drain, as illustrated in <FIG>. Afterwards, remaining fluid (including the rt-PA and dissolved clot) at the site of the ICH <NUM> is aspirated via the same EVD catheter <NUM>, as illustrated in <FIG>. This infusion and aspiration process may be repeated at the physician's discretion. The MISTIE procedure, although reasonably effective in treating an ICH, has limitations that are imposed by the simple design of the conventional EVD catheter <NUM>, which was not designed for the purpose of treating an ICH. In particular, the flow of fluid within the conventional EVD catheter <NUM> can only occur in one direction at a time (either infusion or aspiration, but not both), and furthermore, the rt-PA can only be infused from the EVD catheter <NUM> in a direction perpendicular to a single straight axis, thereby limiting the administration volume and increasing the diffusive resistance of the rt-PA to reach the entire clot mass. As a result, the time to treat the ICH may be unduly increased.

<CIT> discloses an infusion/aspiration catheter comprising an elongate catheter member having a proximal end, a distal end, an infusion lumen and an aspiration lumen extending between the proximal end and the distal end; a distal end tube having a proximal end affixed together at the distal end of elongate catheter body, a lumen in fluid communication with the infusion lumen, and at least one fluid port in fluid communication with the lumen of the distal end tube; an infusion connector affixed to the proximal end of the elongate catheter member in fluid communication with the infusion lumen; and an aspiration connector affixed to the proximal end of the elongate catheter member in fluid communication with the at least one aspiration lumen. That infusion/aspiration catheter is however specifically designed for hemodialysis, hemofiltration and apheresis, and shows thereby limitations with regard to the distribution of the infusion/aspiration functions in cavities.

<CIT> discloses an infusion/aspiration system according to the preamble of claim <NUM>. That system is however specifically directed to tissue treatment.

The invention has for objective to overcome at least one drawback of the above-mentioned prior art.

The invention is directed to an infusion/aspiration system according to claim <NUM>.

Other and further aspects and features of embodiments of the disclosed inventions will become apparent from the ensuing detailed description in view of the accompanying figures.

The drawings illustrate the design and utility of examples and preferred embodiments of the disclosed inventions, in which similar elements are referred to by common reference numerals. It should be noted that the figures are not drawn to scale and that elements of similar structures or functions are represented by like reference numerals throughout the figures. They are not intended as an exhaustive description or limitation of the scope of the disclosed inventions, which is defined only by the appended claims. In order to better appreciate how the above-recited and other advantages and objects of the disclosed inventions are obtained, a more particular description of the disclosed inventions briefly described above will be rendered by reference to specific embodiments thereof, which are illustrated in the accompanying drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered limiting of its scope, and the disclosed inventions are described and explained with additional specificity and detail through the use of the accompanying drawings, in which:.

Referring first to <FIG>, an infusion/aspiration system <NUM> will now be described. The infusion/aspiration system <NUM> generally comprises an introducer sheath <NUM> (which could be the primary access channel and placed separately prior to introduction of subsequent devices, or could be just a transfer sheath used to transfer other devices into a previously placed ancillary sheath), an infusion/aspiration catheter <NUM>, a fluid source <NUM>, and a vacuum source <NUM>.

As best shown in <FIG>, the introducer sheath <NUM> generally comprises an elongated sheath body <NUM> having a proximal end <NUM>, a distal end <NUM>, and a lumen <NUM> extending therebetween. As will be described in further detail below, the infusion/aspiration catheter <NUM> is a purpose-built catheter that functions similarly to a conventional external ventricular drain (EVD) catheter, but has two major differences: (<NUM>) it can be delivered through the lumen <NUM> of the introducer sheath <NUM> (in the same manner as an EVD catheter) and deployed out the distal end <NUM> of the elongated sheath body <NUM> into an anatomical cavity (or clot mass) of interest, but has multiple lumens to allow simultaneous (or staged) infusion of the anatomical cavity of interest with a recombinant tissue plasminogen activator (rt-PA) and aspiration of the fluid, including the dissolved clot, from the anatomical cavity of interest; and (<NUM>) the distal portion of the infusion/aspiration catheter <NUM> expands within the anatomical cavity of interest to better distribute the infusion/aspiration functions via multiple fluid ports. Thus, the infusion/aspiration catheter <NUM> allows for a greater volume of clot to be treated with less diffusion resistance, thereby improving the rate of action of the procedure.

To this end, the infusion/aspiration catheter <NUM> generally comprises an elongate catheter body <NUM> having a proximal end <NUM> and a distal end <NUM>. The elongate catheter body <NUM> is preferably sized to be introduced into a patient in a minimally invasive manner, e.g., through a burr hole (less than one-half inch in diameter) in the cranium of a patient. The elongate catheter body <NUM> may be composed of suitable biocompatible metals, metal alloys, polymers, metal-polymer composites, and the like, or any other suitable biocompatible material. The infusion/aspiration catheter <NUM> further comprises a plurality of lumens <NUM> extending through the elongate catheter body <NUM> between the proximal end <NUM> and the distal end <NUM>. In the illustrated example, the lumens <NUM> are independent of each other. That is, the lumens <NUM> are not in fluid communication with each other at any point. As will be described in further detail below, each lumen <NUM> may be arbitrarily selected to infuse or aspirate fluid. For the purposes of this specification, "aspirate" or "aspiration" means that fluid flows from a higher pressure region to a lower pressure region. However, for the purposes of illustration, the lumens <NUM> are shown divided between a set of infusion lumens 34a and a set of aspiration lumens 34b.

In the illustrated example, the set of infusion lumens 34a comprises two infusion lumens 34a, and the set of aspiration lumens 34b comprises a single infusion lumen 34b. In alternative examples, the set of infusion lumens 34a may comprise a single infusion lumen 34a, and the set of aspiration lumens 34b comprises two infusion lumens 34b. In other alternative examples where the number of lumens <NUM> within the elongate catheter body <NUM> is greater than three, the set of infusion lumens 34a may comprise a plural number of infusion lumens 34a, and the set of aspiration lumens 34b may likewise comprise a plural number of aspiration lumens 34b, or where the number of lumens <NUM> within the elongate catheter body <NUM> is equal to two, the set of infusion lumens 34a may comprise a single infusion lumen 34a, and the set of aspiration lumens 34b may likewise comprise a single aspiration lumen 34b, as further described below with respect to <FIG>.

The infusion/aspiration catheter <NUM> further comprises a plurality of arms <NUM> respectively having proximal ends affixed together at the distal end <NUM> of the elongate catheter body <NUM>, and distal ends affixed together at a distal hub <NUM>. The arms <NUM> may form a unibody structure with the elongate catheter body <NUM>, and thus, may be composed of the same material. In the illustrated example, each of the arms <NUM> has a lumen <NUM> (shown in <FIG>) in fluid communication with a respective one of the lumens <NUM> of the elongate catheter body <NUM>, such that is a one-to-one correspondence between the lumens <NUM> of the elongate catheter body <NUM> and the arms <NUM>, i.e., each lumen <NUM> of the elongated catheter body <NUM> is dedicated to a respective one of the arms <NUM>. Thus, as with the lumens <NUM> in the elongate catheter body <NUM>, each arm <NUM> can be arbitrarily selected to perform a fluid infusion, aspiration, or draining function.

In alternative examples, the number of arms <NUM> may not equal the number of lumens <NUM> of the elongate catheter body <NUM>, in which case, there may not be a one-to-one correspondence between the between the lumens <NUM> of the elongate catheter body <NUM> and the arms <NUM>. For example, a single lumen <NUM> of the elongated catheter body <NUM> can be in fluid communication with more than one lumen <NUM> of the respective arms <NUM>, or multiple lumens <NUM> of the elongate catheter body <NUM> may be in fluid communication with a single lumen <NUM> of a respective arm <NUM>. It is only important that the set of infusion lumens 34a and the set of aspiration lumens 34b of the elongated catheter body <NUM> be independent of each other, such that simultaneous infusion and aspiration of fluid through the infusion/aspiration catheter <NUM> can occur, as described in further detail below.

Each of the arms <NUM> further has at least one fluid port <NUM> in fluid communication with the lumen <NUM> of the respective arm <NUM>. In the illustrated example, each of the arms <NUM> comprise a plurality of fluid ports <NUM> extending along both the outwardly facing side and the inwardly facing side of the respective arm <NUM>. This can be accomplished by perforating the entire thickness of the arm <NUM> to create two sets of aligned fluid ports <NUM> respectively extending along the opposite sides of the arm <NUM>. Alternatively, the fluid ports <NUM> extending along the outwardly facing side and inwardly facing side of each respective arm <NUM> may be offset from each other along the length of the respective arm <NUM>.

In the infusion/aspiration catheter <NUM> illustrated in <FIG>, the number of arms <NUM> equals three, and are equi-distantly spaced from each other in a circumferential manner (in this case, spaced <NUM> degrees from each other), so that the entire anatomical cavity may be equally infused with fluid, although in alternative examples, the arms <NUM> may not be equi-distantly spaced from each other, e.g., to infuse fluid in a particular region or regions of the anatomical cavity in a more focused manner. Although in the infusion/aspiration catheter <NUM> illustrated in <FIG>, the number of arms <NUM> equals three, it should be appreciated that arms <NUM> can have any plural number, including two, as further described below with respect to <FIG>.

The arms <NUM> of the infusion/aspiration catheter <NUM> are pre-shaped to expand outward in the absence of an external force. For example, each of the arms <NUM> may be a shaped element or may comprise an embedded shape memory/superelastic forming element. Thus, as will be described in further detail below, when the infusion/aspiration catheter <NUM> is introduced through the lumen <NUM> of the introducer sheath <NUM>, the arms <NUM> will be compressed by the inward external force exerted by the elongated sheath body <NUM> onto the arms <NUM>, such that the arms <NUM> are straightened into a low-profile geometry, as best illustrated in <FIG>. In contrast, when the arms <NUM> are deployed out the distal end <NUM> of the elongated sheath body <NUM>, the arms <NUM> will outwardly expand in the absence of the external force, thereby placing the arms <NUM> in an expanded geometry to fill the anatomical cavity, as best illustrated in <FIG>.

Referring back to <FIG>, the infusion/aspiration catheter <NUM> further comprises connectors <NUM> (e.g., luer connectors) affixed to the proximal end <NUM> of the elongate catheter body <NUM> in fluid communication with the lumens <NUM> of the elongate catheter body <NUM>. In this example, the connectors <NUM> are separate and free-floating, although in alternative examples, the infusion/aspiration catheter <NUM> may comprise a unitary manifold (or handle) <NUM> comprising the connectors <NUM>, as illustrated in <FIG>. Irrespective of whether the connectors <NUM> are free-floating or integrated into a manifold <NUM>, in the illustrated example, the number of connectors <NUM> equals the number of lumens <NUM> of the elongated catheter body <NUM> (three, in the example illustrated in <FIG>), and are thus, fluidly coupled to the lumens <NUM> in a dedicated manner. Optionally, a valved switched manifold may be used as well, in which case, the lumens <NUM> of the elongate catheter body <NUM> may be switched to either the aspiration or infusion manifold, and therefore, only two connectors <NUM> are needed.

In the illustrated example, the connectors <NUM> are divided between two infusion connectors 56a, which corresponds to the two infusion lumens 34a, and a single aspiration connector 56b, which corresponds to the single aspiration lumen 34b. That is, the two infusion connectors 56a are respectively in fluid communication with the two infusion lumens 34a of the elongate catheter body <NUM>, and the aspiration connector 56b is in fluid communication with the aspiration lumen 34b of the elongate catheter body <NUM>. Of course, in the alternative example where two of the lumens <NUM> are aspiration lumens 34b, and the remaining lumen <NUM> is a single infusion lumen 34a, a single infusion connector 56a may be in fluid communication with the single infusion lumen 34a, and two aspiration connectors 56b may be respectively in fluid communication with the two aspiration lumens 34b.

The fluid source <NUM> may, e.g., take the form of a standard hospital saline bag, and the vacuum source <NUM> may take the form of a vacuum bottle, a syringe, a vacuum pump, or other suitable type of vacuum source. For the purposes of this specification, "vacuum" means a region of lower pressure relative to an inlet pressure. A conventional fluid control system (not shown), including a pump and valves, may be used to control the flow of fluid from the fluid source <NUM> into the infusion/aspiration catheter <NUM>, and the flow of fluid from the infusion/aspiration catheter <NUM> into the vacuum source <NUM>. Exemplary fluid control systems are described in <CIT>. The fluid source <NUM> is connected to the two infusion connectors 56a respectively leading to the two infusion lumens 34a within the elongate catheter body <NUM>, whereas the vacuum source <NUM> is connected to the aspiration connector 56b leading to the aspiration lumen 34b within the elongate catheter body <NUM>. Thus, the fluid source <NUM> is fluidly coupled to the lumens <NUM>, and thus the fluid ports <NUM>, of two of the arms <NUM>, whereas the vacuum source <NUM> is fluidly coupled to the lumen <NUM>, and thus the fluid ports <NUM>, of the remaining arm <NUM>. Extension tubing <NUM> may optionally be used to couple the fluid source <NUM> and vacuum source <NUM> to the respective infusion connectors 56a and aspiration connectors 56b.

It should be appreciated that, although the number of connectors <NUM> have been described as being equal to the number of lumens <NUM> of the elongate catheter body <NUM>, such that the connectors <NUM> can be in respective fluid communication with these lumens <NUM> in a dedicated manner, the number of connectors <NUM> may alternatively be less than the number of lumens <NUM> of the elongate catheter body <NUM>. For example, a single infusion connector 56a can be in fluid communication with the two infusion lumens 34a of the elongate catheter body <NUM>, and a single aspiration connector 56b can be in fluid communication with the aspiration lumen 34b of the elongate catheter body <NUM>.

It should also be appreciated that the designation of any particular connector <NUM> as an infusion connector 56a or an aspiration connector 56b, and thus the designation of any particular lumen (or lumens) <NUM> of the elongate catheter body <NUM> as either an infusion lumen (or lumens) 34a or an aspiration lumen (or lumens) 34b, may be arbitrary in that it depends on whether the fluid source <NUM> or the aspiration pump <NUM> is connected to that particular connector <NUM>. That is, if the fluid source <NUM> is connected to a particular connector <NUM>, that connector <NUM> will be an infusion connector 56a, and the lumen (or lumens) <NUM> of the elongate catheter body <NUM> in fluid communication with that connector 56a will be an infusion lumen (or lumens) 34a. Likewise, if the vacuum source <NUM> is connected to a particular connector <NUM>, that connector <NUM> will be an aspiration connector 56b, and the lumen (or lumens) <NUM> of the elongate catheter body <NUM> in fluid communication with that connector 56b will be an aspiration lumen (or lumens) 34b.

It should also be appreciated that, by not connecting the fluid source <NUM> or the vacuum source <NUM> to any of the particular connectors <NUM>, each of these connectors <NUM> can function as a drainage connector, and thus, any of the lumen (or lumens) <NUM> of the elongated catheter body <NUM> in fluid communication with that connector <NUM> can function as a drainage lumen. As such, the infusion/aspiration catheter <NUM>, at any particular time, can also serve as a drainage catheter, with the expanded arms <NUM> associated with such drainage lumen(s) <NUM> advantageously providing more drainage locations, in addition to more infusion and aspiration locations for the infusion/aspiration functions.

Having described the structure and operation of the infusion/aspiration system <NUM>, one method <NUM> of operating it to treat an anatomical cavity <NUM> of a patient will now be described with respect to <FIG>, as well as <FIG>. In this exemplary method, the anatomical cavity <NUM> is a ventricle within the cranium <NUM> of the patient, and the patient <NUM> has suffered a hemorrhagic stroke of the brain <NUM> (i.e., an ICH), resulting in a clot <NUM> within the ventricle <NUM>, such that the treatment of the patient involves infusing fluid comprising rt-PA into the ventricle <NUM> to dissolve the clot <NUM>, and the rt-PA fluid, along with the dissolved clot <NUM>, is aspirated out from the ventricle <NUM>.

To this end, the method <NUM> comprises introducing the introducer sheath <NUM> into the ventricle <NUM> via a bore hole <NUM> conventionally formed through the cranium <NUM> (step <NUM>) (see <FIG>). The introducer sheath <NUM> may be tracked over an image-guide access probe along a pre-determined non-linear path to minimize potential damage to eloquent tissue. Next, the infusion/aspiration catheter <NUM> is introduced into the lumen <NUM> of the introducer sheath <NUM>, such that the introducer sheath <NUM> applies an external force to the arms <NUM> of the infusion/aspiration catheter <NUM> (shown partially in phantom), thereby straightening the arms <NUM> out into a low-profile geometry (step <NUM>) (see <FIG>).

Next, the arms <NUM> of the infusion/aspiration catheter <NUM> are deployed from the distal end <NUM> of the introducer sheath <NUM> into the ventricle <NUM>, such that the external force is released from the arms <NUM>, thereby allowing the arms <NUM> to expand outward into an expanded geometry (step <NUM>) (see <FIG>). This can be accomplished by, e.g., pushing the infusion/aspiration catheter <NUM> in the distal direction while maintaining the same position of the introducer sheath <NUM>, or pulling the introducer sheath <NUM> in the proximal direction while maintaining the same position of the infusion/aspiration catheter <NUM>. Next, the fluid source <NUM> and the vacuum source <NUM> are connected to the respective infusion connector(s) 56a and aspiration connector(s) 56b of the infusion/aspiration catheter <NUM> (step <NUM>). Although this step is illustrated as occurring after deployment of the arms <NUM> into the ventricle <NUM>, this step can occur any time prior to the infusion/aspiration process, including prior to introduction of the introducer sheath <NUM> into the ventricle <NUM>.

Fluid comprising rt-PA is then simultaneously infused into and aspirated from the ventricle <NUM> (step <NUM>) (see <FIG>). That is, rt-PA fluid will flow from the fluid source <NUM> into the infusion connector(s) 56a, through the two infusion lumens 34a within the elongate catheter body <NUM>, through the lumens <NUM>, and out the fluid ports <NUM>, of two of the arms <NUM>, thereby dissolving the clot <NUM>, and simultaneously, the rt-PA fluid and any dissolved clot <NUM>, will flow into the fluid ports <NUM>, and through the lumen <NUM>, of the remaining arm <NUM>, through the aspiration lumen 34b within the elongate catheter body <NUM>, out of the aspiration connector(s) 56b, and into the vacuum source <NUM>. Alternatively, other forms of treatment, which include the administration of rt-PA, may be administered via the lumens <NUM> of the elongated catheter body <NUM>. Such alternative treatments can, e.g., include saline lavage, which removes unwanted potentially toxic substances, which may arise due to the presence of the clot, and could be the primary cause of tissue damage; introduction of hyperosmotic solution to help reduce local edema; introduction of some unknown therapeutic agent that "fixes brain," etc..

The method <NUM> may optionally comprise draining the fluid by disconnecting one or both of the fluid source <NUM> and aspiration pump <NUM> from one or more of the connectors <NUM>. That is, fluid will drain into the fluid ports <NUM>, and through the lumen(s) <NUM>, of the arm(s) <NUM>, through the lumen(s) <NUM> within the elongate catheter body <NUM>, out of the connector(s) <NUM>, and into a basin under atmospheric pressure. Optionally, an automated system may be used to infuse, aspirate, and/or drain according to a predetermined schedule or in response to a measured input, such as the patient intracranial pressure (ICP) or the static pressure measured from the catheter body <NUM> (which may be a direct measure of the ICP).

After the procedure is completed (i.e., the clot <NUM> has been completely (or sufficiently) evacuated from the ventricle <NUM>), the arms <NUM> of the infusion/aspiration catheter <NUM> can be proximally withdrawn into the introducer sheath <NUM> or the introducer sheath <NUM> can be distally displaced to re-sheath the arms <NUM>, such that the introducer sheath <NUM> again applies an external force to the arms <NUM> of the infusion/aspiration catheter <NUM>, thereby straightening the arms <NUM> back out into a low-profile geometry (step <NUM>). The introducer sheath <NUM>, along with the infusion/aspiration catheter <NUM>, can then be removed from the patient (step <NUM>).

Referring now to <FIG>, an infusion/aspiration system <NUM>' constructed in accordance with another example will now be described. As best shown in <FIG>, the infusion/aspiration system <NUM>' is similar to the infusion/aspiration system <NUM> illustrated in <FIG>, with the exception that it comprises an infusion/aspiration catheter <NUM>' that comprises only two arms <NUM>. In this example, the two arms <NUM> are circumferentially spaced from each other by one hundred eighty degrees, although the two arms <NUM> may be spaced from each other at an angle different from one hundred eight degrees, e.g., to focus infusion of the fluid in only one region of the anatomical cavity.

In this example, the set of infusion lumens 34a comprises a single infusion lumen 34a, and the set of aspiration lumens 34b likewise comprises a single infusion lumen 34b. In the illustrated example, the lumen <NUM> of each of the arms <NUM> in fluid communication with a respective one of the lumens <NUM> of the elongate catheter body <NUM>, such that is a one-to-one correspondence between the lumens <NUM> of the elongate catheter body <NUM> and the arms <NUM>, i.e., each lumen <NUM> of the elongated catheter body <NUM> is dedicated to a respective one of the arms <NUM>.

In alternative examples, the number of arms <NUM> may not equal the number of lumens <NUM> of the elongate catheter body <NUM>, in which case, there may not be a one-to-one correspondence between the between the lumens <NUM> of the elongate catheter body <NUM> and the arms <NUM>. For example, multiple lumens <NUM> of the elongate catheter body <NUM> may be in fluid communication with a single lumen <NUM> of a respective arm <NUM>. Again, it is only important that the set of infusion lumens 34a and the set of aspiration lumens 34b of the elongated catheter body <NUM> be independent of each other, such that simultaneous infusion and aspiration of fluid through the infusion/aspiration catheter <NUM> can occur, as described in further detail below.

A single infusion connector 56a and a single aspiration connector 56b are affixed to the proximal end <NUM> of the elongate catheter body <NUM> in fluid communication with the respective infusion lumen 34a and aspiration lumen 34b of the elongate catheter body <NUM>. In the example illustrated in <FIG>, the connectors <NUM> are separate and free-floating, although in alternative examples, the infusion/aspiration catheter <NUM>' may comprise a unitary manifold (similar to the manifold <NUM> illustrated in <FIG>) comprising the connectors <NUM>. Irrespective of whether the connectors <NUM> are free-floating or integrated into a manifold, the fluid source <NUM> is connected to the infusion connector 56a leading to the infusion lumen 34a within the elongate catheter body <NUM>, whereas the vacuum source <NUM> is connected to the aspiration connector 56b leading to the aspiration lumen 34b within the elongate catheter body <NUM>. Thus, the fluid source <NUM> is fluidly coupled to the lumens <NUM>, and thus the fluid ports <NUM>, of one arm <NUM>, whereas the vacuum source <NUM> is fluidly coupled to the lumen <NUM>, and thus the fluid ports <NUM>, of the remaining arm <NUM>.

In the infusion/aspiration catheter <NUM>' illustrated in <FIG>, instead of, or in addition to, pre-shaping the arms <NUM> to expand outward in the absence of an external force, the infusion/aspiration catheter <NUM>' further comprises an actuation wire <NUM> slidably disposed within an additional lumen (not shown) within the elongated catheter body <NUM>, as best shown in <FIG>. The actuation wire <NUM> (best shown in <FIG>) has a distal end affixed to the distal hub <NUM> of the elongated catheter body <NUM> and a proximal end extending out of the proximal end <NUM> of the elongated catheter body <NUM> for manipulation by a physician to alternately place the arms <NUM> between a low-profile geometry and an expanded geometry. That is, by proximally displacing the actuation wire <NUM> within the lumen (not shown) relative to the elongate catheter body <NUM>, the arms <NUM> will expand outward into the expanded geometry (see <FIG>), and by distally displacing the actuation wire <NUM> within the lumen relative to the elongate catheter body <NUM>, the arms <NUM> will straighten back out into the low-profile geometry (see <FIG>).

Having described the structure and operation of the infusion/aspiration system <NUM>', another method <NUM>' of operating it to treat the anatomical cavity <NUM> of a patient <NUM> will now be described with respect to <FIG>, as well as <FIG>. As with the previous exemplary method <NUM>, in this method <NUM>', the anatomical cavity <NUM> is a ventricle within the cranium <NUM> of the patient <NUM>, and the patient <NUM> has suffered a hemorrhagic stroke, resulting in a clot <NUM> within the ventricle <NUM>, such that the treatment of the patient <NUM> involves infusing fluid comprising rt-PA, into the ventricle <NUM> to dissolve the clot <NUM>, and the rt-PA fluid, along with the dissolved clot <NUM>, is aspirated out from the ventricle <NUM>.

To this end, the method <NUM>' comprises introducing the introducer sheath <NUM> into the ventricle <NUM> via a bore hole <NUM> conventionally formed through the cranium <NUM> (step <NUM>') (see <FIG>). The introducer sheath <NUM> may be tracked over an image-guide access probe along a pre-determined non-linear path to minimize potential damage to eloquent tissue. Next, the infusion/aspiration catheter <NUM> is introduced into the lumen <NUM> of the introducer sheath <NUM>, while the actuation wire <NUM> is displaced distally within the additional lumen (not shown) relative to the elongate catheter body <NUM> to straighten the arms <NUM> into the low-profile geometry (step <NUM>') (see <FIG>). Next, the arms <NUM> of the infusion/aspiration catheter <NUM> are deployed from the distal end <NUM> of the introducer sheath <NUM> into the ventricle <NUM>, and the actuation wire <NUM> is displaced proximally within the additional lumen relative to the elongate catheter body <NUM> to expand the arms <NUM> outward into the expanded geometry (step <NUM>') (see <FIG>). Next, the fluid source <NUM> and the vacuum source <NUM> are connected to the respective infusion connector 56a and aspiration connector 56b of the infusion/aspiration catheter <NUM> (step <NUM>').

Fluid comprising rt-PA is then simultaneously infused into and aspirated from the ventricle <NUM> (step <NUM>) (see <FIG>). That is, rt-PA fluid will flow from the fluid source <NUM> into the infusion connector 56a, through the single infusion lumen 34a within the elongate catheter body <NUM>, through the lumen <NUM>, and out the fluid ports <NUM>, of one of the arms <NUM>, thereby dissolving the clot <NUM>, and simultaneously, the rt-PA fluid and any dissolved clot <NUM>, will flow into the fluid ports <NUM>, and through the lumen <NUM>, of the remaining arm <NUM>, through the aspiration lumen 34b within the elongate catheter body <NUM>, out of the aspiration connector <NUM>, and into the vacuum source <NUM>.

The method <NUM>' may optionally comprise aspirating by draining the fluid by disconnecting one or both of the fluid source <NUM> and aspiration pump <NUM> from one or more of the connectors <NUM>. That is, fluid will drain into the fluid ports <NUM>, and through the lumen(s) <NUM>, of the arm(s) <NUM>, through the lumen(s) <NUM> within the elongate catheter body <NUM>, out of the connector(s) <NUM>, and into a basin under atmospheric pressure (or optionally using an automated system to infuse, aspirate, and/or drain).

After the procedure is completed, the actuation wire <NUM> is displaced distally within the additional lumen relative to the elongate catheter body <NUM> to straighten the arms <NUM> back out into the low-profile geometry (step <NUM>'), and the arms <NUM> of the infusion/aspiration catheter <NUM> can be proximally withdrawn into the introducer sheath <NUM> or the introducer sheath <NUM> can be distally displaced to re-sheath the arms <NUM>. Alternatively, the elongate catheter body <NUM> can be retracted directly into the introducer sheath <NUM>, with the actuation wire <NUM> left free to slide distally as the elongated catheter body <NUM> is resheathed into the introducer sheath <NUM>. The introducer sheath <NUM>, along with the infusion/aspiration catheter <NUM>, can then be removed from the patient (step <NUM>').

Referring now to <FIG>, an infusion/aspiration system <NUM>" constructed in accordance with an embodiment of the disclosed inventions will now be described. The infusion/aspiration system <NUM>" is similar to the infusion/aspiration system <NUM>' illustrated in <FIG>, with the exception that it comprises an infusion/aspiration catheter <NUM>" that has a central aspiration lumen 34b extending through the elongated catheter body <NUM> between the proximal end <NUM> and the distal end <NUM>, with the other three lumens 34a serving as infusion lumens that circumferentially surround the aspiration lumen 34b, as best illustrated in <FIG>. The aspiration lumen 34b terminates in a distal fluid port <NUM> at the distal end <NUM> of the elongate catheter body <NUM> between the proximal ends of the arms <NUM>. In the embodiment illustrated in <FIG>, the central aspiration lumen 34b has a cross-sectional area greater than the cross-section area of each of the surrounding infusion lumens 34a, thereby lending itself well to aspiration.

In the same manner described above with respect to the infusion/aspiration catheter <NUM>' in <FIG>, the connectors <NUM> are affixed to the proximal end <NUM> of the elongate catheter body <NUM> in fluid communication with the lumens <NUM> of the elongate catheter body <NUM>, and can be free-floating, as illustrated in <FIG>, or may be incorporated into a unitary manifold <NUM> in a similar manner illustrated in <FIG>. The number of connectors <NUM> equals the number of lumens <NUM> of the elongated catheter body <NUM> (four, in the embodiment illustrated in <FIG>), and are thus, fluidly coupled to the lumens <NUM> in a dedicated manner. Alternatively, a single connector <NUM> and a single lumen <NUM> of the elongated catheter body <NUM> may be fluidly coupled to the lumens <NUM> of the three arms <NUM>.

In the illustrated embodiment, the connectors <NUM> are divided between three infusion connectors 56a, which corresponds to the three surrounding infusion lumens 34a, and a single aspiration connector 56b, which corresponds to the single central aspiration lumen 34b. That is, the three infusion connectors 56a are respectively in fluid communication with the three infusion lumens 34a of the elongate catheter body <NUM>, and the aspiration connector 56b is in fluid communication with the aspiration lumen 34b of the elongate catheter body <NUM>. Of course, just as with the infusion/aspiration catheter <NUM> of <FIG>, the designation of any particular connector <NUM> as an infusion connector 56a or an aspiration connector 56b, and thus the designation of any particular lumen (or lumens) <NUM> of the elongate catheter body <NUM> as either an infusion lumen (or lumens) 34a or an aspiration lumen (or lumens) 34b, may be arbitrary in that it depends on whether the fluid source <NUM> or the aspiration pump <NUM> is connected to that particular connector <NUM>.

The fluid source <NUM> is connected to the three infusion connectors 56a respectively leading to the three infusion lumens 34a within the elongate catheter body <NUM> (or a single infusion connector leading to a single infusion lumen within the elongate catheter body <NUM>), whereas the vacuum source <NUM> is connected to the aspiration connector 56b leading to the aspiration lumen 34b within the elongate catheter body <NUM>. Thus, the fluid source <NUM> is fluidly coupled to the lumens <NUM>, and thus the fluid ports <NUM>, of the three arms <NUM>, whereas the vacuum source <NUM> is fluidly coupled to the lumen <NUM>, and thus the distal fluid port <NUM> between the proximal ends of the arms <NUM>.

It should be appreciated that, although the number of connectors <NUM> have been described as being equal to the number of lumens <NUM> of the elongate catheter body <NUM>, such that the connectors <NUM> can be in respective fluid communication with these lumens <NUM> in a dedicated manner, the number of connectors <NUM> may alternatively be less than the number of lumens <NUM> of the elongate catheter body <NUM>. For example, a single infusion connector 56a can be in fluid communication with the three surrounding infusion lumens 34a of the elongate catheter body <NUM>, and a single aspiration connector 56b can be in fluid communication with the central aspiration lumen 34b of the elongate catheter body <NUM>.

It should also be appreciated that, just as with the embodiment illustrated in <FIG>, the designation of any particular connector <NUM> as an infusion connector 56a or an aspiration connector 56b, and thus the designation of any particular lumen (or lumens) <NUM> of the elongate catheter body <NUM> as either an infusion lumen (or lumens) 34a or an aspiration lumen (or lumens) 34b, may be arbitrary in that it depends on whether the fluid source <NUM> or the aspiration pump <NUM> is connected to that particular connector <NUM>. That is, if the fluid source <NUM> is connected to a particular connector <NUM>, that connector <NUM> will be an infusion connector 56a, and the lumen (or lumens) <NUM> of the elongate catheter body <NUM> in fluid communication with that connector 56a will be an infusion lumen (or lumens) 34a. Likewise, if the vacuum source <NUM> is connected to a particular connector <NUM> that connector <NUM> will be an aspiration connector 56b, and the lumen (or lumens) <NUM> of the elongate catheter body <NUM> in fluid communication with that connector 56b will be an aspiration lumen (or lumens) 34b.

Furthermore, in an alternative embodiment, the number of lumens <NUM> of the elongate catheter body <NUM> may not match the number of lumens <NUM> of the arms <NUM>. For example, it may be advantageous to have only one infusion lumen 34a that is in fluid communication with the three lumens <NUM> of the arms <NUM> via a coupling at the proximal ends or the distal ends of the arms <NUM>. In this manner, the cross-sectional size of the aspiration lumen 34b may be maximized. Furthermore, in an optional embodiment where the aspiration lumen 34b is large enough to be capable of ingesting large clot masses, and thus, also being capable to be clogged, the infusion/catheter <NUM>" may comprise a maceration tool (not shown), e.g., a rotary cutter/impeller, ultrasound probe, reciprocating wire, etc., that resides in the aspiration lumen 34b.

The method of operating the infusion/catheter system <NUM>" is similar to the operation of the infusion/catheter system <NUM> of <FIG> (see <FIG>), with the exception that the previously infused rt-PA fluid and dissolved clot <NUM> will flow into the distal fluid port <NUM> at the distal end <NUM> of the elongate catheter body <NUM> (instead of into the fluid ports <NUM> of the arm(s) <NUM>, through the central aspiration lumen 34b within the elongate catheter body <NUM>, out of the aspiration connector 56b, and into the vacuum source <NUM>.

Referring now to <FIG>, an infusion/aspiration system <NUM>‴ constructed in accordance with another embodiment of the disclosed inventions will now be described. The infusion/aspiration system <NUM>‴ is similar to the infusion/aspiration system <NUM>" illustrated in <FIG>, with the exception that the arms <NUM> of the infusion/aspiration catheter <NUM>‴ are made smaller to better serve as a filter to prevent, or at least minimize, aspiration of tissue into the distal fluid port <NUM> of the elongate catheter body <NUM>, as best illustrated in <FIG>. The infusion/aspiration catheter <NUM>‴ further optionally comprises a rigid stylet <NUM> removably disposed within the central aspiration lumen 34b of the elongate catheter body <NUM>. The distal hub <NUM> of the infusion/aspiration catheter <NUM>' comprises an aperture <NUM> through which the rigid stylet <NUM> is disposed to straighten the arms <NUM> out into a low-profile geometry. Thus, as it will be described in further detail below, the rigid stylet <NUM> may aid placement of the infusion/aspiration catheter <NUM>‴ within the anatomical cavity, with or without the use of the introducer sheath <NUM>. The rigid stylet <NUM> may be removed from the infusion/aspiration catheter <NUM>‴, so that the central aspiration lumen 34b may subsequently be used to aspirate fluid from the anatomical cavity.

Having described the structure and operation of the infusion/aspiration system <NUM>‴, one method <NUM>‴ of operating it to treat an anatomical cavity <NUM> of a patient <NUM> will now be described with respect to <FIG>, as well as <FIG>. As with the previous exemplary method <NUM>, in this method <NUM>‴, the anatomical cavity <NUM> is a ventricle within the cranium <NUM> of the patient <NUM>, and the patient <NUM> has suffered a hemorrhagic stroke, resulting in a clot <NUM> within the ventricle <NUM>, such that the treatment of the patient <NUM> involves infusing fluid comprising rt-PA, into the ventricle <NUM> to dissolve the clot <NUM>, and the rt-PA fluid, along with the dissolved clot <NUM>, is aspirated out from the ventricle <NUM>.

This method <NUM>‴ does not require the use of an introducer sheath <NUM>, and therefore, such introducer sheath <NUM> is not introduced into the ventricle <NUM>. Instead, the rigid stylet <NUM> is inserted through the central aspiration lumen 34b of the infusion/aspiration catheter <NUM>‴, and then the distal end of the rigid stylet <NUM> is introduced through the aperture <NUM> of the distal hub <NUM> to straighten the arms <NUM> into the low-profile geometry (step <NUM>‴) (see <FIG>). Next, the infusion/aspiration catheter <NUM>‴, along with the rigid stylet <NUM>, is introduced into the ventricle <NUM> through the conventional bore hole <NUM> formed through the cranium <NUM> (step <NUM>‴) (see <FIG>). Next, the rigid stylet <NUM> is removed from the central aspiration lumen 34b of the infusion/aspiration catheter <NUM>‴, thereby allowing the arms <NUM> to expand outward into the expanded geometry (step <NUM>‴) (see <FIG>). Next, the fluid source <NUM> and the vacuum source <NUM> are connected to the respective infusion connector(s) 56a and aspiration connector 56b of the infusion/aspiration catheter <NUM> (step <NUM>‴).

Fluid comprising rt-PA (or other therapeutic solution) is then simultaneously infused into and aspirated from the ventricle <NUM> (step <NUM>‴) (see <FIG>). That is, rt-PA fluid will flow from the fluid source <NUM> into the infusion connector(s) 56a, through the three infusion lumens 34a within the elongate catheter body <NUM>, through the lumens <NUM>, and out the fluid ports <NUM>, of the three arms <NUM>, thereby dissolving the clot <NUM>, and simultaneously, the rt-PA fluid and any dissolved clot <NUM>, will flow into the distal fluid port <NUM>, through the central aspiration lumen 34b, within the elongate catheter body <NUM>, out of the aspiration connector 56b, and into the vacuum source <NUM>.

The method <NUM>‴ may optionally comprise aspirating by draining the fluid by disconnecting one or both of the fluid source <NUM> and aspiration pump <NUM> from one or more of the connectors <NUM>. That is, fluid will drain into the fluid ports <NUM>, and through the lumen(s) <NUM>, of the arm(s) <NUM>, and/or into the distal port <NUM>, through the lumen(s) <NUM> within the elongate catheter body <NUM>, out of the connector(s) <NUM>, and into a basin under atmospheric pressure (or optionally using an automated system to infuse, aspirate, and/or drain).

After the procedure is completed, the rigid stylet <NUM> is reinserted through the central aspiration lumen 34b of the infusion/aspiration catheter <NUM>‴ until the distal end of the rigid stylet <NUM>, and then the distal end of the rigid stylet <NUM> is introduced through the aperture <NUM> of the distal hub <NUM> to straighten the arms <NUM> into the low-profile geometry. The infusion/aspiration catheter <NUM> can then be removed from the patient.

Although the embodiments described herein lend themselves well to the simultaneous infusion and aspiration of fluid into and out of an anatomical cavity, it should be appreciated that in some circumstances, such simultaneous infusion and aspiration of fluid may not be needed. In this case, the infusion and aspiration of the fluid into and out of the anatomical cavity can be staged (i.e., performed serially). For example, with respect to the infusion/aspiration catheters <NUM>, <NUM>', and <NUM>", all three lumens <NUM> of the elongated catheter body <NUM> can be used as infusion lumens to deliver the rt-PA (or other therapeutic solution) into the anatomical cavity, and then all three lumens <NUM> of the elongated catheter body <NUM> can be used as aspiration lumens to aspirate the rt-PA (or other therapeutic solution) from the anatomical cavity. Thus, all of the lumens <NUM> may be configured for infusion at once, and likewise, all of the lumens <NUM> may be configured for aspiration at once. In this manner, infusion out of the lumens <NUM> of all three of the arms <NUM> will advantageously deliver the rt-PA to a larger more spread out region. The lumens <NUM> may also be switched between aspiration and infusion into any configuration at will or via an automated control system. In this case, a single connector <NUM> can be affixed to the proximal end <NUM> of the elongate catheter body <NUM> in fluid communication with the lumens <NUM> of the elongate catheter body <NUM>, such that the fluid source <NUM> can be connected to the single connector <NUM>, and after the infusion process is completed, the aspiration pump <NUM> can be connected to the same connector <NUM>.

Claim 1:
An infusion/aspiration system (<NUM>), comprising:
an infusion/aspiration catheter (<NUM>", <NUM>"'), comprising:
an elongate catheter body (<NUM>) having a proximal end (<NUM>), a distal end (<NUM>), at least one infusion lumen (34a) and an aspiration lumen (34b) extending between the proximal end (<NUM>) and the distal end (<NUM>), the aspiration lumen (34b) terminating in a distal fluid port (<NUM>) at the distal end (<NUM>) of the elongate catheter body (<NUM>);
a plurality of arms (<NUM>) respectively having proximal ends affixed together at the distal end (<NUM>) of the elongate catheter body (<NUM>), the distal fluid port (<NUM>) of the elongate catheter body (<NUM>) being between the proximal ends of the plurality of arms (<NUM>), the arms (<NUM>) having lumens (<NUM>) in fluid communication with the at least one infusion lumen (34a), each of the arms (<NUM>) having at least one fluid port (<NUM>) in fluid communication with the lumen (<NUM>) of the respective arm (<NUM>);
at least one infusion connector (56a) affixed to the proximal end (<NUM>) of the elongate catheter body (<NUM>) in fluid communication with the at least one infusion lumen (34a);
an aspiration connector (56b) affixed to the proximal end (<NUM>) of the elongate catheter body (<NUM>) in fluid communication with the at least one aspiration lumen (34b); and
a distal hub (<NUM>) at which distal ends of the arms (<NUM>) are affixed together, the plurality of arms (<NUM>) being pre-shaped to expand outward in the absence of an external force;
a vacuum source (<NUM>) or drain connected to the aspiration connector (56b);
characterized in that the infusion/aspiration system (<NUM>) further comprises:
a source of recombinant tissue plasminogen activator (rt-PA) (<NUM>) connected to the at least one infusion connector (56a).