Abstract:
A rapid exchange fluid jet thrombectomy device for removal of thrombus or unwanted tissue debris from a vein, artery or the like. The device includes a semi-rigid intermediate tube between a proximal and a distal exhaust tube which accommodates a guidewire tube exit located along the catheter at less than one-half the length of the catheter measured from the catheter most distal point. Such a location of the guidewire is convenient for maneuvering and longitudinal advancement of the guidewire, as well as maneuvering and longitudinal advancement of the catheter by one practitioner.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     This patent application is a continuation-in-part of Ser. No. 09/888,455 entitled “Single Operator Exchange Fluid Jet Thrombectomy Device” filed on Jun. 25, 2001, now U.S. Pat. No. 6,755,803, which is a continuation-in-part of Ser. No. 09/356,783 entitled “Rheolytic Thrombectomy Catheter and Method of Using Same” filed on Jul. 16, 1999, now abandon, which is a divisional of Ser. No. 09/019,728 entitled “Rheolytic Thrombectomy Catheter and Method of Using Same” filed on Feb. 6, 1998, now U.S. Pat. No. 5,989,210. 
     This patent application is also related to Ser. No. 09/417,395 entitled “Thrombectomy Catheter and System” (as amended) filed on Oct. 13, 1999, pending, which is a continuation-in-part of Ser. No. 08/349,665 entitled “Thrombectomy Method” filed on Dec. 5, 1994, under appeal, which is a divisional of Ser. No. 08/006,076 entitled “Thrombectomy Device” filed on Jan. 15, 1993, now U.S. Pat. No. 5,370,609, which is a continuation of Ser. No. 07/563,313 entitled “Thrombectomy Device and Method” filed on Aug. 6, 1990, abandoned. 
     This patent application is also related to Ser. No. 08/351,605 entitled “Thrombectomy and Tissue Removal Method and Device” filed on Dec. 8, 1994, pending, which is a divisional of Ser. No. 07/976,367 entitled “Thrombectomy and Tissue Removal Method and Device” filed on Nov. 13, 1992, abandoned, which is a continuation-in-part of Ser. No. 07/563,313 entitled “Thrombectomy Device and Method” filed on August 06, 1990, abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a rapid exchange catheter, such as a fluid jet material removal catheter and system, to a method of constructing same, and to a method of using same in diagnosis or treatment of a body vessel or other body cavity or tissue. 
     The present invention relates to apparatus for use in treatment of the human body. More particularly, the present invention relates to an elongated device which may be a single catheter assembly or a multiple component catheter assembly and which is suitable for use through percutaneous or other access, for endoscopic procedures, or for intraoperative use in either open or limited access surgical procedures. Still more particularly, the present invention relates to an elongated device in the form of a fluid jet thrombectomy catheter, being adapted for fragmentation and removal of thrombus or other unwanted material from blood vessels or body cavities by using high velocity saline (or other suitable fluid) jets to macerate the thrombus or other unwanted material. The elongated device bears certain similarities to known waterjet thrombectomy catheter devices and can be used as such, but differs therefrom in several material respects, with major differences being the construction of the device from simpler tubular components, utilization of a semi-rigid intermediate tube to facilitate transition between a guidewire-containing and a non-guidewire-containing portion, and enhanced utility of the device in rapid exchange methods with a single operator. The device is particularly advantageous in a cross stream configuration but can be adapted to other forms as well. The cross stream jets create a recirculation flow pattern optimized for clearing a large cross section of mural thrombus or other similar material. Further, the present invention also relates to a system constituted either by the combination of the elongated device with both pressurized fluid source means and exhaust regulation means or by the combination of the elongated device with only pressurized fluid source means. Other ancillary devices or features can be utilized or incorporated such as introduction devices, guiding devices, isolation or filtering devices, centering devices, imaging devices, infusion or withdrawal devices, dilatation devices, energy delivery devices, and so forth, to aid in diagnosis or treatment of a patient, without departing from the scope of the present invention. The use of a semi-rigid intermediate tube can be applied to other elongated devices such as intravascular catheters, balloon catheters, device delivery catheters, and so forth, and is not limited solely to fluid jet material removal catheters. 
     2. Description of the Prior Art 
     Procedures and apparatus have been developed for ease in removing tissue and various deposits. Several such devices employ a jet of saline as the working tool to help break up the tissue deposit and further provide a suction means to remove the deposit. U.S. Pat. No. 5,135,482 to Neracher describes a hydrodynamic device for removal of organic deposit from a human vessel. A supply of saline is delivered by a high pressure duct to the distal end of a catheter. The saline exits the duct as a jet that is directed generally forward and directly toward the tissue to be broken up. The duct is contained within and can move axially with respect to a hose that is positioned around the duct. A vacuum suction is applied to the hose to remove the debris that is created from the broken-up tissue. There is no guidewire lumen and no provision for rapid exchange of the device over a guidewire. 
     Another drainage catheter, described by Griep in U.S. Pat. No. 5,320,599, has a discharge channel and a pressure channel. The channels are formed into a single catheter tube such that the two tubes are fixed with respect to each other. This device does not have a guidewire lumen and cannot be used as a rapid-exchange wire-guided device. 
     Waterjet thrombectomy catheters have been described (including U.S. Pat. Nos. 5,370,609, 5,989,210, 6,096,001 and 6,224,570) in which a distal-to-proximal directed waterjet(s) flow(s) past a window, orifice or gap at the distal end of the catheter, re-entering the catheter and pushing flow through an evacuation lumen. When placed in a vessel containing thrombus and activated, the high velocity jet(s) will entrain surrounding fluid and thrombus into the window, orifice or gap region, where the high shear forces of the jet(s) will macerate the thrombus. The macerated particles will be removed from the body by the pressure generated on the distal end of the evacuation lumen by the impingement of the high velocity waterjet(s). 
     A limitation of these waterjet thrombectomy catheters has been the inability to remove organized, wall-adherent thrombus from large vessels. In accordance with the present invention, the rapid exchange fluid jet thrombectomy device described overcomes this limitation by utilizing cross stream jets to optimize the recirculation pattern at the tip of the device and increase the drag force exerted on the mural thrombus to break it free from the vessel wall and allow it to be removed by the device. 
     Prior art devices often required the use of more than one operator where one operator must stabilize the guidewire while the second operator introduces the catheter over the guidewire into the anatomy. Various approaches have been used to overcome this difficulty, with varying degrees of success. Bonzel U.S. Pat. No. 4,762,129, Yock U.S. Pat. No. 5,040,548, Keith U.S. Pat. No. 5,156,594, Keith et al. U.S. Pat. No. 5,370,616, Horzewski et al. U.S. Pat. No. 5,496,346, Enger U.S. Pat. No. 5,728,067, and Enger U.S. Pat. No. 5,980,486 disclose balloon catheters which include a short guidewire lumen near the distal end, to provide for rapid or single-operator exchange. The Bonzel patent discloses a balloon catheter which has a short guidewire lumen only passing through a distal balloon and alongside a balloon inflation lumen which terminates in the balloon; this approach is not appropriate for a cross stream type fluid jet catheter where internal pressure would cause a significant leakage from the exhaust lumen through the proximal opening of the guidewire lumen and into the vessel, and a side-by-side asymmetric configuration would cause the guidewire or guidewire lumen to interfere with access of the jets or the cross stream jets to the thrombus and would be stiffer, thereby not being able to track as well. The Yock patent discloses a balloon catheter with a guidewire lumen which extends some distance proximal to the balloon, with the proximal and distal inflation lumens and guidewire lumen being preferably of flexible plastic material; the Yock device lacks a semi-rigid intermediate tube which provides reliable geometry to ensure free guidewire movement in this region, and provides a more efficient yet controllable fabrication. As with the Bonzel and Yock devices, the Keith et al., Horzewski et al., and Enger devices are balloon catheters not adapted for fluid jet thrombectomy. The present invention provides a high-pressure supply lumen to supply the fluid jets, and an exhaust lumen for removal of thrombus or unwanted tissue debris, both extending along the length of the device, in addition to a shorter guidewire lumen extending only a portion of the length of the device. None of the prior art devices provides these three lumens to provide the form or function of the present invention. 
     Co-pending application Ser. No. 09/888,455, assigned to the same assignee as the present invention, discloses a fluid jet thrombectomy catheter which is adapted for single operator exchange. That device provides an interchangeable system where one inner catheter assembly containing fluid jet orifices can be substituted for a different inner catheter assembly according to the particular requirements of the material removal procedure in the vasculature. However, that device requires two separate components, resulting in compatibility and alignment issues necessitating more complex designs with alignment stops and more expensive fabrication than the present design, and requires additional manipulations by the physician to utilize the device. When such interchangeable inner catheter assemblies are not required, the present invention provides a simpler unitary device with more straightforward operation. 
     The present invention overcomes complexities of the prior art by introducing a semi-rigid intermediate tube which connects a distal exhaust tube, a guidewire lumen, and a proximal exhaust tube in an efficient and easily fabricated configuration, and provides reliable operation over a guidewire and which is applicable for removal of unwanted deposits in the body, such as, but not limited to, thrombus in a blood vessel or cardiac chamber or extravascular space, renal or biliary deposits, hematomas in the brain or brain ventricles or elsewhere, material in the gastrointestinal tract, material in the respiratory tract or lungs, or material associated with a joint, for example. The present invention is particularly useful in a fluid jet thrombectomy device. 
     The present invention also includes a rapid exchange fluid jet system, and a semi-rigid intermediate tube, and a method of fabricating a multiple-lumen rapid exchange catheter, and a method of removing unwanted tissue from the body using a rapid exchange fluid jet catheter and system. 
     SUMMARY OF THE INVENTION 
     The present invention, a rapid exchange fluid jet thrombectomy device, is a medical device for removal of material such as thrombus from a vessel or other body cavity. As shown in one or more embodiments, the rapid exchange fluid jet thrombectomy device can function as a rheolytic thrombectomy catheter for removing tissue from a vessel or other body cavity. 
     A catheter according to the present invention has a high pressure lumen which carries pressurized working fluid such as saline solution from the proximal end to the distal end which has a jet emanator, where the working fluid exits to form one or more high velocity fluid jets. The jet(s) can be directed proximally, distally, with radial componency, or various directions; the jet(s) directed proximally are preferred. When the high velocity jets are operating, blood, thrombus, or other fluid or unwanted material is drawn in through inflow orifice(s) or other openings into a distal exhaust tube due to a low pressure zone created by the high velocity jets. Further, proximal to this low pressure zone, the distal exhaust tube thereby becomes somewhat pressurized, with the pressure being able to drive fluid and unwanted material proximally along the exhaust tube. Preferably, there is one or more outflow orifice(s) in the pressurized region of the distal exhaust tube, so that a portion of the fluid and unwanted material (which has been broken into small pieces by the high velocity jets) passes out from the distal exhaust tube into the body vessel or cavity in which the catheter has been placed, creating one or more “cross stream” jet(s) with radial componency. These cross stream jets act to break unwanted material off the surface of the body vessel or cavity and aid in creating a fluid recirculation pattern for more effective removal of unwanted material. The basic design of the rapid exchange fluid jet catheter could function without separate outflow orifice(s), but these outflow orifices being separate from inflow orifice(s) or openings provides a more efficient and effective removal of unwanted material. A separate guidewire tube inside the distal exhaust tube provides for passage of a guidewire through the most distal tip of the distal exhaust tube and out the proximal end of the distal exhaust tube. The distal end of the catheter may preferably be tapered to better approximate the diameter of the guidewire and provide better passage within the body vessel or cavity or past a tight stenosis or lesion. The proximal portion of the rapid exchange fluid jet catheter has a proximal exhaust tube but does not contain a guidewire lumen. At the proximal end of the catheter, there is a manifold which includes a high pressure connector and an exhaust connector or, alternatively, can be a continuous line from a waste bag to the exhaust tube or to the pump. The distal exhaust tube typically extends less than half the length of the catheter, and the proximal exhaust tube typically extends greater than half the length of the catheter. 
     Interposed between the proximal exhaust tube and the distal exhaust tube is a relatively short semi-rigid intermediate tube. The intermediate tube is round at its proximal end to fit snugly inside the distal end of the proximal exhaust tube. The intermediate tube is formed or otherwise constructed to have a truncated and rounded slot which is shallower towards the proximal end and deeper toward the distal end. This truncated and rounded slot is sized so that the guidewire tube will fit inside the truncated and rounded slot at the distal end, and the intermediate tube is formed so that it fits snugly inside the proximal end of the distal exhaust tube. The proximal end of the guidewire tube is located along the truncated and rounded slot of the semi-rigid intermediate tube, and preferably near the proximal end of the distal exhaust tube. The guidewire tube is positioned and sized so that a guidewire can pass through the distal end of the guidewire tube located at or near the distal tapered end of the catheter, through the length of the distal exhaust tube, and then exit through the proximal end of the distal exhaust tube located near the proximal end of the intermediate tube. The high pressure lumen connects to the high pressure connector or can run all the way to a pump at the proximal manifold, and passes within the proximal exhaust tube, the intermediate tube, and the distal exhaust tube. Adhesive sealant may be used to bond the various components to provide a fluid seal between components. Alternatively, thermal bonding or heat-shrinking can be used, or the components may be sized to form a tight, secure fit without additional bonding. 
     The present invention also includes a design of an intermediate tube for a rapid exchange catheter, which may be a fluid jet catheter, a balloon catheter, or other diagnostic or treatment catheter. 
     The present invention also includes a rapid exchange fluid jet catheter system incorporating a rapid exchange fluid jet catheter, a high pressure fluid source, and a collection system with optional exhaust regulation means, where a guidewire passes through only the distal portion of the rapid exchange fluid jet catheter. 
     The present invention also includes a method of fabricating such a rapid exchange catheter utilizing a semi-rigid intermediate tube. The method includes the steps of:
         a. providing a proximal exhaust tube, a distal exhaust tube, a guidewire tube, and a semi-rigid intermediate tube with a truncated and rounded slot which is deeper at the distal end than at the proximal end;   b. fitting the proximal exhaust tube to the proximal end of the semi-rigid intermediate tube and fitting the distal exhaust tube to the distal end of the semi-rigid intermediate tube; and,   c. positioning the guidewire tube so that it extends along the length of the distal exhaust tube and terminates at or near the distal end of the distal exhaust tube, and extends proximally to a point along the truncated and rounded slot of the semi-rigid intermediate tube, thereby providing communication for passage from the outside of the rapid exchange catheter at the distal end of the guidewire tube located at or near the distal tapered end of the catheter, through the length of the distal exhaust tube, i.e., through the guidewire tube, and then exiting through the proximal end of the distal exhaust tube at a location near the proximal end of the semi-rigid intermediate tube.       

     The above embodiment of the present invention also provides a method of removing thrombus or other unwanted material from a body vessel or cavity. The method includes the steps of:
         a. providing a guidewire and rapid exchange fluid jet catheter including a manifold, a proximal exhaust tube, a distal exhaust tube, a semi-rigid intermediate tube, a guidewire tube, a high pressure lumen, a proximal high pressure connector, and a distal jet emanator;   b. advancing the guidewire through the vasculature and past the vascular site containing thrombus or other unwanted material;   c. introducing the rapid exchange fluid jet catheter by passing the guidewire through the guidewire tube and advancing the rapid exchange fluid jet catheter along the guidewire to the site containing thrombus or other unwanted material; and,   d. providing a high pressure supply of saline or other fluid to the high pressure lumen via the proximal high pressure connector or direct connection to a pump, so as to cause at least one high velocity fluid jet to emanate from the jet emanator and to entrain thrombus or other unwanted material into the distal exhaust tube via an inflow orifice where the thrombus or other unwanted material is macerated and propelled proximally along the distal exhaust tube, semi-rigid intermediate tube, and proximal exhaust tube for removal from the body, while either maintaining a positive or negative fluid balance at the distal tip.       

     The method of removing thrombus or other unwanted material from a body vessel or cavity preferably includes providing a distal exhaust tube with outflow orifices, which create cross stream jets for enhanced removal of material. 
     According to one or more embodiments of the present invention, there is provided a rapid exchange fluid jet thrombectomy device, including a manifold including connector and other devices, a proximal exhaust tube extending distally from the manifold, a semi-rigid intermediate tube extending distally from the proximal exhaust tube, a truncated and rounded slot extending along a greater portion of the semi-rigid intermediate tube, a distal exhaust tube extending distally from the semi-rigid intermediate tube, an accessible guidewire tube accommodated by and extending along and from a portion of the truncated and rounded slot into and along the greater portion of the distal exhaust tube, a fluid jet emanator connected to a high pressure tube extending through the distal exhaust tube, the semi-rigid intermediate tube, and the proximal exhaust tube, and a plurality of inflow and outflow orifices located at the distal end of the distal exhaust tube. One or more alternative embodiments disclose a distal exhaust tube incorporating a bi-directional fluid jet emanator which emanates high velocity jet flow in a distal direction from a plurality of distally facing jet orifices for breakup and macerating of thrombotic deposits or lesions in coordination with pluralities of outflow orifices and inflow orifices, and which also emanates high velocity jet flow in a proximal direction from a proximally facing orifice in coordination with an inflow orifice to carry off macerated thrombotic deposits or lesions outwardly through the lumen of a distal exhaust tube. 
     One significant aspect and feature of the present invention is a rapid exchange fluid jet thrombectomy device which can be operated by one practitioner. 
     Another significant aspect and feature of the present invention is a rapid exchange fluid jet thrombectomy device having inflow orifices and outflow orifices to create cross stream jets. 
     Still another significant aspect and feature of the present invention is a guidewire tube for passage of a guidewire through the distal portion of the device. 
     Yet another significant aspect and feature of the present invention is a semi-rigid intermediate tube to provide connection between a proximal exhaust tube, a distal exhaust tube, and a guidewire tube. 
     A further significant aspect and feature of the present invention is an easier method of utilizing a fluid jet catheter due to a unitary design. 
     A still further significant aspect and feature of the present invention is the ability to incorporate various emanator shapes, styles and designs. 
     An additional significant aspect and feature of the present invention is the reduction of fabrication costs by eliminating complicated extruded shapes, minimizing the number of components, reducing the complexity of the components, and improving the quality of the components. 
     Another significant aspect and feature of the present invention is the inclusion of structural members which allow minimizing the outer diameter of the device while maximizing the inner diameter of the device. The outer diameter of the device is minimized to provide the least intrusive profile and the inside diameter of the device is maximized for higher free and less restrictive exhaust flow. 
     A yet further significant aspect and feature of the present invention is coating the device hydrophilically for improved movement along a guidewire, as well as improved trackability. 
     Another significant aspect and feature of the present invention is the incorporation of an exhaust tube support ring and of the structure of a fluid jet emanator in conjunction with marker bands to provide for stabilization of the inflow and outflow orifices when passed through tortuous vascular paths, as well as the ability to be suitably detected by fluoroscopic identifying measurement devices. 
     Another significant aspect and feature of the present invention is the ability to inject medicinal or detectable fluids into the body through the exhaust port of a manifold. 
     Another significant aspect and feature of the present invention is the ability to inject drugs through emanator jets via a saline supply bag. 
     Alternatively, another significant aspect and feature of the present invention is the use of a bi-directional fluid jet emanator for directing high velocity jet flows in both distal and proximal directions. 
     Alternatively, another significant aspect and feature of the present invention is the use of a dedicated set of inflow and outflow orifices and dedicated jet orifices for use in the breakup and maceration and re-maceration of lesions and thrombotic material. 
     Alternatively, another significant aspect and feature of the present invention is the use of a dedicated inflow orifice and dedicated jet orifice for use in the evacuation of macerated and re-macerated particles of lesions and thrombotic material through a distal exhaust tube. 
     Having thus described embodiments and significant aspects and features of the present invention, it is the principal object of the present invention to provide a rapid exchange fluid jet thrombectomy device and method of using same to remove thrombus or other unwanted material from a body vessel or other body cavity. 
     One object of the present invention is to provide a rapid exchange fluid jet thrombectomy device of such size, flexibility and construction as to enable it to pass readily through the tortuous pathways found in the fragile vessels of the heart, the brain or other body areas, including the more fragile veins. 
     Another object of the present invention is to provide a rapid exchange fluid jet thrombectomy device with means for producing one or more jets of saline and projecting them in a proximal direction to create a vacuum near the site of thrombus or other unwanted material while pressurizing the exhaust passage. 
     Yet another object of the present invention is to provide a rapid exchange fluid jet thrombectomy device with outflow orifice means for producing one or more cross stream jets for enhanced removal of thrombus or other unwanted material. 
     Still another object of the present invention is to provide an improved method of removing thrombus or other unwanted material from an obstructed body vessel. 
     A further object of the present invention is to provide a smaller diameter rapid exchange fluid jet thrombectomy device wherein the guidewire passes through only a portion of the device resulting in less pressure drop along the exhaust passage, which can also improve the flow of dye through the guide catheter, thereby increasing catheter performance and procedural performances. 
     A still further object of the present invention is to provide an efficient, reliable, and less costly method of fabricating a rapid exchange catheter by utilizing a semi-rigid intermediate tube formed with a truncated and rounded slot. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other objects of the present invention and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein: 
         FIG. 1  illustrates a plan view of the visible components of a rapid exchange fluid jet thrombectomy device, the present invention, including a manifold with a strain relief and a catheter extending distally from the strain relief; 
         FIG. 2  illustrates a plan view of the rapid exchange fluid jet thrombectomy device, the present invention, indicating high pressure fluid source and collection chamber connections to the manifold; 
         FIG. 3  illustrates an exploded and foreshortened isometric view of the components of the catheter of the rapid exchange fluid jet thrombectomy device distal to the strain relief; 
         FIG. 4  illustrates an isometric view of the one-piece semi-rigid intermediate tube; 
         FIG. 5  illustrates a cross section view of the catheter along line  5 — 5  of  FIG. 1 ; 
         FIG. 6  illustrates an end view of the one-piece semi-rigid intermediate tube of  FIG. 4 ; 
         FIG. 7  illustrates a cross section of the catheter along line  7 — 7  of  FIG. 5 ; 
         FIG. 8  illustrates a cross section of the catheter along line  8 — 8  of  FIG. 5 ; 
         FIG. 9  illustrates an exploded isometric view depicting the fluid jet emanator, the exhaust tube support ring, and the high pressure tube in relationship to one another; 
         FIG. 10  illustrates a side view in partial cross section of the components illustrated in  FIG. 9  in assembled condition; 
         FIG. 11  illustrates a proximal end view of the fluid jet emanator; 
         FIG. 12  illustrates a cross sectional view of the distal portion of the distal exhaust tube along line  12 — 12  of  FIG. 1 ; 
         FIG. 13  illustrates the rapid exchange fluid jet thrombectomy device connected to ancillary devices; 
         FIG. 14  illustrates a cross section view in partial cutaway of the rapid exchange fluid jet thrombectomy device in the performance of the method of use thereof; 
         FIG. 15 , an alternate embodiment, illustrates an exploded and foreshortened isometric view of the components of an alternative catheter, including a bi-directional fluid jet emanator, of the rapid exchange fluid jet thrombectomy device distal to the strain; 
         FIG. 16  illustrates an exploded isometric view depicting the bi-directional fluid jet emanator, the exhaust tube support ring, and the high pressure tube in relationship to one another; 
         FIG. 17  illustrates a side view in partial cross section of the components illustrated in  FIG. 16  in assembled condition; 
         FIG. 18  illustrates a cross sectional view of the distal portion of the distal exhaust tube of the alternate embodiment; and, 
         FIG. 19  illustrates a cross section view in partial cutaway of the rapid exchange fluid jet thrombectomy device incorporating the bi-directional fluid jet emanator in the performance of the method of use thereof. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  illustrates a plan view of the visible components of a rapid exchange fluid jet thrombectomy device  10 , the present invention, including a manifold  12  and a catheter  14 . The manifold  12  includes a distally located Luer fitting  16  and strain relief  18 , an exhaust branch  20  and threaded branch end  22 , a proximally located Luer fitting  24 , and threaded high pressure connection port  26 . The catheter  14 , a unitary elongated structure, extends distally from the strain relief  18  and includes multiple components comprising, but not limited to, a one-piece proximal exhaust tube  28 , a one-piece semi-rigid intermediate tube  30 , and a one-piece distal exhaust tube  32  connected in series fashion, a guidewire tube  46  (FIG.  3 ), and other features and components as described herein. The proximal exhaust tube  28  and the distal exhaust tube  32  are fashioned of braided polyimide to provide for minimal wall thickness for improved free exhaust and dye flow characteristics, while still maintaining pushability through the vasculature, but still maintaining not overly stiff properties. 
     The proximal end  34  of the one-piece proximal exhaust tube  28  secures to the manifold  12  by the use of the Luer fitting  16  and extends distally through the strain relief  18  to a location where the distal end  36  terminates around and about the proximally located tubular portion  38  ( FIG. 3 ) of the semi-rigid intermediate tube  30 . The proximal end  40  of the one-piece distal exhaust tube  32  aligns over and about part of the distally located tubular portion  42  ( FIG. 3 ) of the semi-rigid intermediate tube  30  and extends distally to a tapered tip  44  which can be flexible in design. 
       FIG. 2  illustrates a plan view of the rapid exchange fluid jet thrombectomy device  10 , the present invention, indicating high pressure fluid source and collection chamber connections to the manifold  12 . 
       FIG. 3  illustrates an exploded isometric view of the components of catheter  14  distal to the strain relief  18 , the components being foreshortened with respect to length for the purpose of illustration and clarity. The outwardly visible length of the catheter  14  is comprised of outwardly visible joined components including the proximal exhaust tube  28 , the semi-rigid intermediate tube  30 , the distal exhaust tube  32 , and a small portion of a guidewire tube  46 . Other components are housed within, around and about the catheter  14 . 
     A high pressure tube  48  with a lumen  78  ( FIG. 5 ) extends from the manifold  12  as previously described through a lumen  50  in the proximal exhaust tube  28 , through a lumen  52  in the semi-rigid intermediate tube  30 , and through a lumen  54  ( FIG. 12 ) of the distal exhaust tube  32  and connectively terminates at a fluid jet emanator  56 . The high pressure tube  48  also extends through and is attached to an exhaust tube support ring  58  such as by welding or other suitable means. The fluid jet emanator  56  as well as the distal end  60  of the high pressure tube  48  locate distally in the lumen  54  of the distal exhaust tube  32 , as shown in  FIG. 12. A  radiopaque marker band  70  aligns over and about the distal region of the distal exhaust tube  32  and is forcibly secured thereto in captured alignment and in transmitted frictional engagement with the fluid jet emanator  56 , as shown in FIG.  12 . The exhaust tube support ring  58  locates in lumen  54  of the distal exhaust tube  32  in alignment with a radiopaque marker band  72  which forcibly secures over and about the distal exhaust tube  32  in transmitted frictional engagement, as shown in FIG.  12 . The guidewire tube  46 , having a lumen  62 , extends distally from the semi-rigid intermediate tube  30 , through the exhaust tube support ring  58 , through a passageway  64  in the fluid jet emanator  56 , through the lumen  54  of the distal exhaust tube  32  where the distal end  65  terminates securely at the distal end of the tapered tip  44 . Heat can be applied to form a tapered tip  44  of increasingly flexible shape, in a distal direction, at the end of the distal exhaust tube  32 , as well as to engagingly secure the distal end of the guidewire tube  46  centrally within the tapered tip  44 . The tapered tip  44  may also be formed through a cold draw down process or may be physically attached through adhesives or polymer reintegration. The tapered tip  44  and the guidewire tube  46  are continuous. The proximal end  66  of the guidewire tube  46  is securely accommodated by a truncated and rounded slot  68  of the semi-rigid intermediate tube  30  described with reference to  FIG. 4. A  plurality of outflow orifices  74   a - 74   n  and a plurality of inflow orifices  76   a - 76   n  spaced distal to the outflow orifices  74   a - 74   n  are included around and about the distal region of the distal exhaust tube  32 . 
       FIG. 4  illustrates an isometric view of the one-piece semi-rigid intermediate tube  30 , which could alternatively be rigid, and which can be formed, molded, machined, extruded or otherwise fashioned of metal, plastic or other suitable materials. The one-piece semi-rigid intermediate tube  30  includes a proximally located tubular portion  38  of lesser diameter than the greater length distally located tubular portion  42 . The semi-rigid intermediate tube  30  includes geometry in the form of a truncated and rounded slot  68  of decreasing depth, in a proximal direction, which accommodates a guidewire tube  46  ( FIG. 5 ) extending along a greater portion of the length of the distally located tubular portion  42 . The truncated and rounded slot  68  is substantially formed in the shape of a nearly full semi-circular arc at the extreme distal end of the distally located tubular portion  42 . The arc, while the radius remains constant, is decreased progressing proximally from the extreme distal end of the distally located tubular portion  42  to provide for angled transitional accommodation of the guidewire tube  46  shown in FIG.  5 . Lumen  52  interior to the semi-rigid intermediate tube  30  accommodates the high pressure tube  48  and also functions as part of the overall effluent exhaust path formed with lumens  50  and  54 . 
       FIG. 5  illustrates a cross section view of the catheter  14  along line  5 — 5  of  FIG. 1 , where all numerals correspond to those elements previously described. Shown in particular is the semi-rigid intermediate tube  30  intimately engaging the proximal exhaust tube  28 , the distal exhaust tube  32 , and the proximal end  66  of the guidewire tube  46 . A low profile mating of the distal end  36  of the proximal exhaust tube  28  with the semi-rigid intermediate tube  30  is accomplished by engagement of the distal end  36  of the proximal exhaust tube  28  with the reduced radius proximally located tubular portion  38  of the semi-rigid intermediate tube  30 . Adhesives, welding, thermal bonding, heat shrinking, or other such suitable methods involving or not involving heat-generated bonding, can be incorporated to bond the distal end  36  of the proximal exhaust tube  28  with the reduced radius proximally located tubular portion  38  of the semi-rigid intermediate tube  30 . The proximal end  66  of the guidewire tube  46  is accommodated by the truncated and rounded slot  68  of the semi-rigid intermediate tube  30  and secured thereto by an adhesive, by welding or other such suitable method. The proximal end  66  of the guidewire tube  46  is of such length that the outer profile of the distal exhaust tube  32  or the outer profile of the proximal exhaust tube  28  is not exceeded to maintain the desired minimal catheter profile. The portion of the truncated and rounded slot  68  which is not occupied by the proximal end  66  of the guidewire tube  46  and which is proximal thereto can also be utilized to accommodate a guidewire without structure interference. The proximal end  40  of the distal exhaust tube  32  intimately engages a portion of the distally located tubular portion  42  of the semi-rigid intermediate tube  30  and can be bonded thereto by an adhesive, welding, thermal bonding, heat shrinking, or other such suitable method involving or not involving heat-generated bonding. Also illustrated is the high pressure tube  48 , having the lumen  78 , passing through the lumens  50 ,  52  and  54 . Lumen  50  of the proximal exhaust tube  28 , lumen  52  of the semi-rigid intermediate tube  30 , and lumen  54  of the distal exhaust tube  32  are connected to function as an exhaust route extending the length of the catheter  14 . 
       FIG. 6  illustrates an end view of the one-piece semi-rigid intermediate tube  30  of  FIG. 4 , where all numerals correspond to those elements previously described. Illustrated in particular is the extreme distal end of the truncated and rounded slot  68  having a maximum arc. 
       FIG. 7  illustrates a cross section of the catheter  14  along line  7 — 7  of  FIG. 5 , where all numerals correspond to those elements previously described. Illustrated in particular is the lumen  50  of the proximal exhaust tube  28  which functions as an exhaust route with minimal obstructions or restrictions therein. 
       FIG. 8  illustrates a cross section of the catheter  14  along line  8 — 8  of  FIG. 5 , where all numerals correspond to those elements previously described. Illustrated in particular is the alignment and accommodation of the guidewire tube  46  in the truncated and rounded slot  68  of the semi-rigid intermediate tube  30 . Also illustrated are the lumens  50 ,  52  and  54  in alignment to function as an exhaust route through the catheter  14 . 
       FIG. 9  illustrates an exploded isometric view depicting the fluid jet emanator  56 , the exhaust tube support ring  58 , and the high pressure tube  48  in relationship to one another. The exhaust tube support ring  58  secures such as by a weld  80  or other suitable attachment method to the lower surface of the high pressure tube  48  thereby fixing the exhaust tube support ring  58  at a suitable position along the interior (lumen  54 ) of the distal exhaust tube  32  for engagement with the distal exhaust tube  32  by compressional frictional engagement of the radiopaque marker band  72  over and about the distal exhaust tube  32 . 
     The high pressure tube  48  is reduced in diameter at the high pressure tube distal end  60  to engage the fluid jet emanator  56 . The fluid jet emanator  56  is described with reference to  FIGS. 9 ,  10  and  11 . The fluid jet emanator  56  is built as a structure outwardly resembling the general shape of a spool. The fluid jet emanator  56  includes a cylindrical main body  82 , an annular manifold groove  83  in the form of a circular groove at the proximal end of the cylindrical main body  82 , a centrally located tubular extension  85  extending proximally from the proximal end of the main body  82  and being coaxial with the annular manifold groove  83 , and a manifold plate  86  aligned to the annular manifold groove  83  and to the planar annular surfaces adjacent to the annular manifold groove  83  and having a plurality of jet orifices  88   a - 88   n , a centrally located hole  90 , and an offset hole  94 . The centrally located hole  90  is aligned to and accommodated by the tubular extension  85 . The manifold plate  86  is also aligned substantially to the distal end of the main body  82  during the mating of the centrally located hole  90  and the tubular extension  85 . A passageway  64  aligns to the longitudinal axis of the main body  82 , the center of the tubular extension  85 , the center of the hole  90  of the manifold plate  86 , and the center of an annular groove  96  about the main body  82 . As shown in  FIG. 10 , an annular manifold  84  is formed when the manifold plate  86  is mated over and about the annular manifold groove  83  and adjacent planar annular surfaces of the fluid jet emanator  56  at which time the plurality of jet orifices  88   a - 88   n  and the offset hole  94  are brought into close communicational alignment with the annular manifold groove  83  and annular manifold  84 . 
     High pressure fluid  98  such as saline or other suitable solution is delivered through the lumen  78  of the high pressure tube  48  to the fluid jet emanator  56  and distributed through the annular manifold  84  to the plurality of jet orifices  88   a - 88   n  whereby high velocity jet flow  100  emanates proximally, as described later in detail. 
     The radiopaque marker band  70  and the annular groove  96  in the main body  82  of the fluid jet emanator  56  are utilized to fix the fluid jet emanator  56  and associated components and structures at the proper position within the distal end of the distal exhaust tube  32 , as illustrated in FIG.  12 . The radiopaque marker band  70  positions over and about the distal end of the distal exhaust tube  32  for engagement with the distal exhaust tube  32  by compressional frictional engagement of the radiopaque marker band  70  over and about distal exhaust tube  32  in the co-located region of the annular groove  96  and the distal exhaust tube  32 . 
       FIG. 10  illustrates a side view in partial cross section of the components illustrated in  FIG. 9  in assembled condition. Illustrated in particular is the connective relationship of the lumen  78  of the high pressure tube  48  to the annular manifold  84 . High pressure fluid  98  is delivered to the annular manifold  84  through the lumen  78  and is emanated outwardly and proximally through the jet orifices  88   a - 88   n  in the form of high velocity jet flow  100  in multiple jet streams. Integrity of the annular manifold  84  is ensured by an annular weld  101  joining the common mated peripheries of the manifold plate  86  and adjacent main body  82  of the fluid jet emanator  56  and by another annular weld  103  joining the junction of the tubular extension  85  and the manifold plate  86 . An annular weld  105  securingly seals the distal end  60  of the high pressure tube  48  within the offset hole  94 , thereby ensuring the integrity of the connection of the lumen  78  with the annular manifold  84 . 
       FIG. 11  illustrates a proximal end view of the fluid jet emanator  56 , where all numerals correspond to those elements previously described. Illustrated in particular is the distribution and alignment of the jet orifices  88   a - 88   n  about the annular manifold  84  through which high velocity jet flow  100  emanates proximally. 
       FIG. 12  illustrates a cross section view of the distal portion of the distal exhaust tube  32  along line  12 — 12  of FIG.  1 . Shown in the illustration is the positioning of the radiopaque marker bands  70  and  72  around and about the distal portion of the distal exhaust tube  32 . The distally located radiopaque marker band  70  is forcibly applied over and about the distal exhaust tube  32  to cause frictional annular engagement of a portion of the distal exhaust tube  32  with all or part of the annular groove  96  of the fluid jet emanator  56 . Such frictional engagement is sufficient to place the outer radius surface of the radiopaque marker band  70  in a position lesser than the general and greater outer radial surface of the distal exhaust tube  32  thereby providing in part a distal exhaust tube  32  having no elements protruding beyond the general outer radial surface thereof for unimpeded and smooth distal or proximal transition of the catheter  14  within a vein, artery or the like. The frictional engagement of the radiopaque marker band  70  over and about the distal exhaust tube  32  is not abrupt in nature with respect to the smooth surface of the distal exhaust tube  32  wherein opposed curved annular surfaces  102  and  104  are formed adjacent to the edges of the radiopaque marker band  70 . The curved annular surfaces  102  and  104  being generally smooth in nature also aid in unimpeded and smooth distal or proximal transition of the catheter  14  within a vein, artery or the like. The proximally located radiopaque marker band  72  is also forcibly applied over and about the distal exhaust tube  32  to cause frictional annular engagement of a portion of the distal exhaust tube  32  with the exhaust tube support ring  58  much in the same manner as the radiopaque marker band  70 . Such frictional engagement is sufficient to place the outer radius surface of the radiopaque marker band  72  in a position lesser than the general and greater outer radial surface of the distal exhaust tube  32  thereby providing in part a distal exhaust tube  32  having no elements protruding beyond the general outer radial surface thereof for unimpeded and smooth distal or proximal transition of the catheter  14  within a vein, artery or the like. The curved annular surfaces  106  and  108  being generally smooth in nature also aid in unimpeded and smooth distal or proximal transition of the catheter  14 . 
     Structure is provided to nurture and aid introduction of and passage of the distal portion of the distal exhaust tube  32  through blood vessels, arteries and the like to the site of thrombotic deposits or lesions. The tapered tip  44 , as opposed to a rounded but nontapered tip, can part and can more easily penetrate thrombotic deposits or lesions during insertional travel in a distal direction instead of advancing or pushing such thrombotic deposits or lesions distally. The decreasing diameter in a distal direction of the tapered tip  44  also allows for increasing flexibility to negotiate and pass through tortuous paths. The portion of the distal exhaust tube  32  which immediately follows the tapered tip  44  on a tortuous negotiation and passage is influenced by supportive structure which offers reinforcement of the distal exhaust tube  32  against bending or collapsing due to negative pressures, especially in the regions in close proximity to or including the inflow orifices  76   a - 76   n  and the outflow orifices  74   a - 74   n . The exhaust tube support ring  58  and the fluid jet emanator  56  are examples of structures offering support or reinforcement along the distal exhaust tube  32  in the regions of the inflow and outflow orifices  76   a - 76   n  and  74   a - 74   n , respectively. The exhaust tube support ring  58  and the fluid jet emanator  56  also serve as forms and contribute to maintaining the diameter of the distal exhaust tube  32 . Such support allows the use of thinner wall dimension for the distal tube  32  to allow for a larger and more effective and efficient sized lumen  54 , as well as contributing to a lesser sized outer diameter. Such support also contributes to supportively maintaining the diameter and overall shape of the distal exhaust tube  32  when the catheter  14  is pushed or advanced along a vein or vessel, as well as providing torsional support. 
     MODE OF OPERATION 
       FIGS. 13 and 14  illustrate the mode of operation where  FIG. 13  illustrates the rapid exchange fluid jet thrombectomy device  10  connected to ancillary devices, and where  FIG. 14  illustrates a cross section view in partial cutaway of the rapid exchange fluid jet thrombectomy device  10  in the performance of the method of use thereof. The mode of operation is best understood by referring to  FIGS. 13 and 14 , as well as previously described figures. 
     In  FIG. 13 , the rapid exchange fluid jet thrombectomy device  10  is shown engaged over and about a guidewire  110  where the guidewire  110  (previously engaged into a vein or artery) first engages the lumen  62  of the guidewire tube  46  at the tapered tip  44  of the distal exhaust tube  32  followed by exiting of the guidewire  110  from the lumen  62  at the proximal end  66  of the guidewire tube  46  at the semi-rigid intermediate tube  30 . A high pressure fluid source  112  and a high pressure fluid pump  114  connect as shown to the manifold  12  via the threaded high pressure connection port  26  by a threaded nut  116  or optionally by a direct connection. An optional exhaust regulator  118  and a collection chamber  120  connect to the threaded branch end  22  of the exhaust branch  20  of the manifold  12  by a Luer fitting  122  as shown. 
       FIG. 14  illustrates a cross section view in partial cutaway of the rapid exchange fluid jet thrombectomy device  10  in the performance of the method of use thereof, with particular attention given to the distal portion of the distal exhaust tube  32  including the flexible tapered tip  44  positioned in a blood vessel  124 , artery or the like at the site of a thrombotic deposit or lesion  126 . Multiple jet streams of high velocity jet flow  100  of saline (or other suitable fluid) are shown being emitted in a proximal direction from the jet emanator  56  to impinge upon and carry away thrombotic deposits or lesions  126 . Other jet emanators can be incorporated within the distal portion of the distal exhaust tube  32  as an alternative to the jet emanator  56  illustrated in this figure to emanate or emit one or more high velocity jet flow(s)  100  distally along or near the longitudinal axis of the distal exhaust tube  32  to accomplish the same purpose as that described for the jet emanator  56 . The high velocity jet flow(s)  100  of saline pass outwardly through the outflow orifice(s)  74   a - 74   n  in a radial direction creating crossflow jet(s)  128  (lower velocity jet(s)) directed outwardly toward the wall of the blood vessel  124  and are influenced by the low pressure at the inflow orifice(s)  76   a - 76   n  to cause the crossflow jet(s)  128  to flow circumferentially and distally to impinge on, provide drag forces on, and break up thrombotic deposits or lesions  126  and to, by entrainment, urge and carry along the particles of thrombotic deposits or lesions  126  through the inflow orifice(s)  76   a - 76   n , a relatively low pressure region, into the high velocity jet flows  100  where the thrombus is further macerated into microscopic particles, and into the distal exhaust tube lumen  54  (FIG.  12 ). A certain portion of this macerated debris which is mixed with fresh saline is removed through the exhaust tube lumen  54  and a certain portion flows back out the outflow orifices  74   a - 74   n  and recirculates to break up more debris which is returned to the inflow orifices  76   a - 76   n . In this way, much more flow circulates through the system than is injected through the jet orifices  88   a - 88   n . For purposes of illustration and example, three to ten times more flow circulates through the system than is delivered by the jet orifices  88   a - 88   n . The entrainment through the inflow orifice(s)  76   a - 76   n  is based on entrainment by the high velocity jet flow(s)  100 . The outflow is driven by internal pressure which is created by the high velocity jet flow(s)  100  and the fluid entrained through the inflow orifice(s)  76   a - 76   n . Enhanced clot removal is attainable because of the recirculation pattern established between inflow and outflow orifices  76   a - 76   n  and  74   a - 74   n , which creates a flow field that maximizes drag force on wall-adhered thrombus. Since the entrained thrombus is macerated into microscopic particles, those particles that exit the outflow orifices  74   a - 74   n  are not of sufficient size to significantly block the distal circulation, and will be re-entrained into the inflow orifices  76   a - 76   n  at a high rate. In a no flow situation or when flow is stopped with another device such as an occlusion balloon, then material can be recirculated and rediluted until all that remains is saline and all particles are removed. 
       FIG. 15 , an alternate embodiment, illustrates an exploded isometric view of the components of an alternate catheter  14   a  distal to the strain relief  18 , the components being foreshortened with respect to length for the purpose of illustration and clarity. Many of the components utilized in the catheter  14   a  are the same as those utilized in the catheter  14  but some are different, and therefore the catheter  14  has been redesignated as catheter  14   a . The fluid jet emanator  56  is redesignated as the bi-directional fluid jet emanator  130 , and the distal exhaust tube  32  is redesignated as the distal exhaust tube  132 . Other associated components may be utilized and may be relocated as shown herein. The outwardly visible length of the catheter  14   a  is comprised of outwardly visible joined components including the proximal exhaust tube  28 , the semi-rigid intermediate tube  30 , the distal exhaust tube  132 , and a small portion of the guidewire tube  46 . Other components or structures are housed within, around and about the catheter  14   a.    
     The high pressure tube  48  with a lumen  78  ( FIG. 5 ) extends from the manifold  12 , as previously described, through the lumen  50  in the proximal exhaust tube  28 , through the lumen  52  in the semi-rigid intermediate tube  30 , and through a lumen  134  ( FIG. 18 ) of the distal exhaust tube  132  and connectively terminates at the bi-directional fluid jet emanator  130 . The high pressure tube  48  also extends through and is attached to the exhaust tube support ring  58  such as by welding or other suitable means. The bi-directional fluid jet emanator  130  as well as the distal end  60  of the high pressure tube  48  locate distally in the lumen  134  of the distal exhaust tube  132 , as shown in  FIG. 18. A  radiopaque marker band  70  aligns over and about the distal region of the distal exhaust tube  132  and is forcibly secured thereto in captured alignment and in transmitted frictional engagement with the bi-directional fluid jet emanator  130 , as shown in FIG.  18 . The exhaust tube support ring  58  locates in lumen  134  of the distal exhaust tube  132  in alignment with a radiopaque marker band  72  which forcibly secures over and about the distal exhaust tube  132  in transmitted frictional engagement, as shown in FIG.  18 . The guidewire tube  46 , having the lumen  62 , extends distally from the semi-rigid intermediate tube  30 , through the exhaust tube support ring  58 , into the lumen  134  of the distal exhaust tube  132 , as shown in  FIG. 18 , through a passageway  172  in the bi-directional fluid jet emanator  130 , and continues through the lumen  134  of the distal exhaust tube  132  where the distal end  65  terminates securely at the distal end of the tip  136 . The proximal end  66  of the guidewire tube  46  is securely accommodated by the truncated and rounded slot  68  of the semi-rigid intermediate tube  30  described with reference to  FIG. 4. A  plurality of inflow orifices are located along and about the distal region of the distal exhaust tube  132 , including inflow orifices  138   a - 138   n  in distally near juxtaposition to the radiopaque marker band  70  and the bi-directional fluid jet emanator  130  (FIG.  18 ); and a plurality of outflow orifices  140   a - 140   n  are located along and about the distal region of the distal exhaust tube  132  distally from the radiopaque marker band  70  and the bi-directional fluid jet emanator  130 , as also shown in FIG.  18 . In addition, an inflow orifice  142  is located in proximally near juxtaposition to the radiopaque marker band  70 , as also shown in FIG.  18 . 
       FIG. 16  illustrates an exploded isometric view depicting the bi-directional fluid jet emanator  130 , the exhaust tube support ring  58 , and the high pressure tube  48  in relationship to one another. The exhaust tube support ring  58  secures such as by a weld  80  or other suitable attachment method to the lower surface of the high pressure tube  48  thereby fixing the exhaust tube support ring  58  at a suitable position along the interior (lumen  134 ) of the distal exhaust tube  132  for engagement with the distal exhaust tube  132  by compressional frictional engagement of the radiopaque marker band  72  over and about the distal exhaust tube  132 . 
     The high pressure tube  48  is reduced in diameter at the high pressure tube distal end  60  to engage the bi-directional fluid jet emanator  130 . The bi-directional fluid jet emanator  130 , being similar in many aspects to the fluid jet emanator  56 , is described with reference to  FIGS. 16 and 17 . The bi-directional fluid jet emanator  130  is built as a structure outwardly resembling the general shape of a spool. The bi-directional fluid jet emanator  130  includes a cylindrical main body  144 , an annular manifold groove  146  in the form of a circular groove at the proximal end of the cylindrical main body  144 , a centrally located tubular extension  148  extending proximally from the proximal end of the main body  144  and being coaxial with the annular manifold groove  146 , and a manifold plate  150  aligned to the annular manifold groove  146  and to the planar annular surfaces adjacent to the annular manifold groove  146  and having a jet orifice  152 , a centrally located hole  154 , and an offset hole  156 . The centrally located hole  154  is aligned to and accommodated by the tubular extension  148 . The manifold plate  150  is also aligned substantially to the distal end of the main body  144  during the mating of the centrally located hole  154  and the tubular extension  148 . As shown in  FIG. 17 , an annular manifold  158  is formed when the manifold plate  150  is mated over and about the annular manifold groove  146  and adjacent planar annular surfaces of the bi-directional fluid jet emanator  130  at which instance the jet orifice  152  and the offset hole  156  are brought into close communicational alignment with the annular manifold groove  146  and annular manifold  158 . The bi-directional fluid jet emanator  130  also includes another annular manifold  160  ( FIG. 17 ) opposite the annular manifold  158  which is formed in a like and similar fashion to the annular manifold  158  and which is located at the distal end of the bi-directional fluid jet emanator  130 . 
     With reference to  FIGS. 16 and 17 , the annular manifold  160  and other structure at the distal end of the bi-directional fluid jet emanator  130  is now described. The distal end of the bi-directional fluid jet emanator  130  includes an annular manifold groove  162  in the form of a circular groove at the distal end of the cylindrical main body  144 , a centrally located tubular extension  164  extending distally from the distal end of the main body  144  and being coaxial with the annular manifold groove  162 , and a manifold plate  166  aligned to the annular manifold groove  162  and the planar annular surfaces adjacent to the annular manifold groove  162  and having a plurality of jet orifices  168   a - 168   n  distributed about the manifold plate  166 , and a centrally located hole  170 . The centrally located hole  170  is aligned to and accommodated by the tubular extension  164 . The manifold plate  166  is also aligned substantially to the distal end of the main body  144  during the mating of the centrally located hole  170  and the tubular extension  164 . The annular manifold  160  is formed when the manifold plate  166  is mated over and about the annular manifold groove  162  and adjacent planar annular surfaces of the bi-directional fluid jet emanator  130  at which instance the jet orifices  168   a - 168   n  and the hole  170  are brought into close communicational alignment with the annular manifold groove  162  and annular manifold  160 . A passageway  172  aligns to the longitudinal axis of the main body  144 , the centers of the holes  154  and  170  of the manifold plates  150  and  166 , and the center of an annular groove  174  about the main body  144 . An additional passageway  178  communicatingly extends through the main body  144  between the proximally located annular manifold  158  and the distally located annular manifold  160 . 
     The radiopaque marker band  70  and the annular groove  174  located about the main body  144  of the bi-directional fluid jet emanator  130  are utilized to fix the bi-directional fluid jet emanator  130  and associated components and structures at the proper position within the distal end of the distal exhaust tube  132 , as illustrated in FIG.  18 . The radiopaque marker band  70  positions over and about the distal end of the distal exhaust tube  132  for engagement with the distal exhaust tube  132  by compressional frictional engagement of the radiopaque marker band  70  over and about distal exhaust tube  132  in the co-located region of the annular groove  174  and the distal exhaust tube  132 . 
       FIG. 17  illustrates a side view in partial cross section of the assembled components illustrated in  FIG. 16  in assembled condition. Illustrated in particular is the connective relationship of the lumen  78  of the high pressure tube  48  to the annular manifold  158 , to the passageway  178 , and to the annular manifold  160 . High pressure fluid  176  delivered to the annular manifold  158  through the lumen  78  is emanated outwardly and proximally through the jet orifice  152  in the form of high velocity jet flow  180  in a jet stream. High pressure fluid  176  delivered to the annular manifold  158  through the lumen  78  communicates with annular manifold  160  via the interconnecting passageway  178  and is emanated outwardly and distally through the jet orifices  168   a - 168   n  in the form of high velocity jet flow  182  in jet streams. Integrity of the annular manifold  158  is ensured by an annular weld  184  joining the common mated peripheries of the manifold plate  150  and adjacent main body  144  of the bi-directional fluid jet emanator  130  and by another annular weld  186  joining the junction of the tubular extension  148  and the manifold plate  150 . In a similar fashion, integrity of the annular manifold  160  is ensured by an annular weld  188  joining the common mated peripheries of the manifold plate  166  and adjacent main body  144  of the bi-directional fluid jet emanator  130  and by another annular weld  190  joining the junction of the tubular extension  164  and the manifold plate  166 . An annular weld  192  securingly seals the distal end  60  of the high pressure tube  48  within the offset hole  156 , thereby ensuring the integrity of the connection of the lumen  78  with the annular manifold  158 . 
       FIG. 18  illustrates a cross section view of the distal portion of the distal exhaust tube  132  in a fashion such as incorporated along line  12 — 12  of  FIG. 1  showing the relationship of the bi-directional fluid jet emanator  130  to the distally located inflow orifices  138   a - 138   n  and outflow orifices  140   a - 140   n  and to the proximally located inflow orifice  142 . Shown in the illustration is the positioning of the radiopaque marker bands  70  and  72  around and about the distal portion of the distal exhaust tube  132  which also form curved annular surfaces  102 ,  104 ,  106  and  108 , as previously described. The distally located radiopaque marker band  70  is forcibly applied over and about the distal exhaust tube  132  to cause frictional annular engagement of a portion of the distal exhaust tube  132  with all or part of the annular groove  174  of the bi-directional fluid jet emanator  130 . Such frictional engagement is sufficient to place the outer radius surface of the radiopaque marker band  70  in a position lesser than, the general and greater outer radial surface of the distal exhaust tube  132 , thereby providing, in part, a distal exhaust tube  132  having no elements protruding beyond the general outer radial surface thereof for unimpeded and smooth distal or proximal transition of the catheter  14   a  within a vein, artery or the like in a manner and fashion such as previously described. 
     MODE OF OPERATION 
     The mode of operation of the rapid exchange fluid jet thrombectomy device  10  incorporating the catheter  14   a  including the bi-directional fluid jet emanator  130  and the alternative distal exhaust tube  132  and associated components and structures is best understood by referring particularly to  FIG. 19  which illustrates a cross section view in partial cutaway of the distal region of the catheter  14   a  of the rapid exchange fluid jet thrombectomy device  10  in the performance of the method of use thereof. The distal exhaust tube  132  is configured and connected in a manner and fashion such as described in relation to  FIG. 3  but where the distal exhaust tube  132  is substituted for the distal exhaust tube  32 . 
       FIG. 19  shows in particular the distal portion of the distal exhaust tube  132  including the tip  136  positioned in a blood vessel  124 , artery or the like at the site of a thrombotic deposit or lesion  126 . High velocity jet flow occurs in opposing directions from the bi-directional fluid jet emanator  130 . High velocity jet flow  182  emanating distally from the bi-directional fluid jet emanator  130  serves to provide for breaking up and macerating or re-macerating of thrombotic deposits or lesions  126 , and high velocity jet flow  180  emanating proximally from the bi-directional fluid jet emanator  130  serves to provide for removal of macerated or re-macerated thrombotic deposits or lesions  126  through the lumen  134  of the distal exhaust tube  132 . 
     With respect to distally directed jet streams, multiple jet streams of high velocity jet flow  182  of saline (or other suitable fluid), such as also viewed in  FIG. 17 , are shown being emanated in a distal direction from the bi-directional fluid jet emanator  130  to impinge upon and carry away thrombotic deposits or lesions  126 . The high velocity jet flow(s)  182  of saline pass outwardly through the outflow orifice(s)  140   a - 140   n  in a radial direction creating crossflow jet(s)  194  (lower velocity jet(s)) directed outwardly toward the wall of the blood vessel  124  and are influenced by the low pressure at the inflow orifice(s)  138   a - 138   n  to cause the crossflow jet(s)  194  to flow circumferentially and proximally to impinge on, provide drag forces on, and break up thrombotic deposits or lesions  126  and to, by entrainment, urge and carry along the particles of thrombotic deposits or lesions  126  through the inflow orifice(s)  138   a - 138   n , a relatively low pressure region, and thence into the high velocity jet flows  182  once again where the thrombus is further macerated into microscopic particles. A certain portion of this macerated debris which is mixed with fresh saline is removed through the inflow orifice  142 , as later described, through the distal exhaust tube lumen  134 , and a certain portion flows into the inflow orifices  138   a - 138   n  and back out the outflow orifices  140   a - 140   n  and recirculates to break up more debris which is returned to the inflow orifices  138   a - 138   n . In this way, much more flow circulates through the system than is injected through the jet orifices  168   a - 168   n . For purposes of illustration and example, three to ten times more flow circulates through the system than is delivered by the jet orifices  168   a - 168   n . The entrainment through the inflow orifice(s)  138   a - 138   n  is based on entrainment by the high velocity jet flow(s)  182 . Enhanced clot removal is attainable because of the recirculation pattern established between inflow and outflow orifices  138   a - 138   n  and  140   a - 140   n , which creates a flow field that maximizes drag force on wall-adhered thrombus. Since the entrained thrombus is macerated into microscopic particles, those particles that exit the outflow orifices  140   a - 140   n  are not of sufficient size to significantly block the distal circulation, and will be re-entrained into the inflow orifices  138   a - 138   n  at a high rate or exhausted through the inflow orifice  142 . 
     With respect to the proximally directed jet stream, a jet stream of high velocity jet flow  180  of saline (or other suitable fluid), such as also viewed in  FIG. 17 , is shown being emitted in a proximal direction from the bi-directional fluid jet emanator  130  by the proximally facing jet orifice  152  to create a relatively low pressure at the inflow orifice  142  to induct and carry away macerated or re-macerated thrombotic deposits or lesions  126  suspended in saline fluid. Although only one jet orifice  152  is shown in the preceding illustrations, one or more proximally facing orifices could be incorporated. The macerated or re-macerated thrombotic deposits or lesions  126  suspended in saline fluid are carried through the lumen  134  of the distal exhaust tube  132  to be collected as previously described. 
     In a no flow situation or when flow is stopped with another device such as an occlusion balloon, then material can be recirculated and rediluted until all that remains is saline and all particles are removed. 
     Various modifications can be made to the ion without departing from the apparent scope hereof.