Patent Publication Number: US-10314609-B2

Title: Enhanced cross stream mechanical thrombectomy catheter

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation Application of U.S. application Ser. No. 14/676,192, filed on Apr. 1, 2015, now U.S. Pat. No. 9,833,257, which is a Continuation Application of U.S. application Ser. No. 14/090,179, filed on Nov. 26, 2013, now U.S. Pat. No. 8,998,843, which is a divisional application of U.S. application Ser. No. 13/453,498, filed on Apr. 23, 2012, now U.S. Pat. No. 8,597,238, issued Dec. 3, 2013, which is a divisional of U.S. application Ser. No. 12/174,978, filed Jul. 17, 2008, now U.S. Pat. No. 8,162,877, issued Apr. 24, 2012, which is a divisional of U.S. application Ser. No. 11/009,720, filed on Dec. 10, 2004, which is abandoned, the contents of which are incorporated herein by reference. This application is related to U.S. application Ser. No. 10/455,096 filed Jun. 5, 2003, now U.S. Pat. No. 7,226,433, issued Jun. 5, 2007. 
    
    
     BACKGROUND 
     The present disclosure is for a thrombectomy catheter, and more particularly, relates to an enhanced cross stream mechanical thrombectomy catheter which accommodates interchanging of guidewires through rear loading of a guidewire, as well as loading of a guidewire in a conventional manner, and also provides for improved cross stream ablation at a thrombus site. The intended use of embodiments of this disclosure are for the detachment and removal of unwanted tissues, such as thrombus, from within biological conduits. 
     DESCRIPTION OF PRIOR ART 
     In current cross stream catheters, vessel damage by the multiple inflow/outflow cross stream catheters involves the vessel wall being sucked into the catheter at the side inlet orifice of the catheter. The high velocity fluid jets nick the vessel that is sucked into the catheter side inflow orifice. With the design described by the present disclosure, the vessel is pushed away by a single side outflow. The side of the catheter with no orifices is pushed against the vessel and consequently no damage results. This new mechanical thrombectomy design is referred to as the Enhanced Cross Stream Mechanical Thrombectomy Catheter with Backloading Manifold. The design employs one set of inflow and outflow orifices instead of the symmetrical multiple orifice configuration. Generally speaking, the cross sectional area of multiple sets of outflow/inflow orifices of prior art devices are newly combined into one set having a larger but equal cross sectional outflow/inflow orifice area to substantially increase and concentrate the cross stream action on one side of the device, thereby increasing the localized flow intensity considerably. In the present disclosure, all the flow is concentrated to one set of orifices and, in addition, the area for recirculation is maximized since it is designed to have a guidewire removed or pulled back out of the flow zone while using the device. Removing the guidewire from the orifice area of the catheter removes a substantial fluid restriction between the single side inflow orifice and the single side outflow orifice. In theory, removing this fluid restriction in all cross stream catheter designs should increase catheter performance. However, in the multiple orifice pair arrangements of the prior art, internal turbulent eddies consumed the area and an increase in performance often did not accompany the retraction of the guidewire. The single inflow orifice and outflow orifice arrangement of the present disclosure simplifies the internal fluid pathway, and as a result, marked flow increase associated with guidewire removal is consistent and dramatic. The guidewire does not need to be pulled out completely to achieve substantial improvements in efficacy. In fact, even with the guidewire in place, it is much more effective than similarly sized cross stream thrombectomy catheters. Furthermore, retracting the guidewire to free the orifice area of the catheter results in an even greater increase in catheter performance. This removal of the guidewire from the region of cross stream action (i.e., from the ID of the catheter) greatly increases the flow volume and reduces flow resistance in which recirculation can more readily occur, thereby enhancing function. Furthermore, in existing designs, a guidewire cannot be reliably retracted from the catheter without the potential of the guidewire exiting the inflow orifices when the physician pushes it back through the tip of the device. The orifices of existing designs can be made smaller, but then a greater number of orifices must be provided to maintain suitable flow, resulting in limiting cross stream action since the resistance though smaller orifices is greater. Therefore, a new arrangement was created to solve the problem. Specifically, the high pressure tube is placed in the center of the large inflow and outflow orifice effectively creating two smaller orifices with the least amount of resistance to flow with minimized manufacturing cost. The high pressure tube further directs the guidewire up and out of the tip of the distal portion of the catheter due to its geometry (i.e., rounded surface, thickness keeps wire away from wall, etc.). In summary, by utilizing one set of large inflow and outflow orifices with the ability to remove and replace the guidewire when desired, the cross stream ablation action can be concentrated and enhanced. Furthermore, the ability of removing and replacing the guidewire at the flexible tip or at the proximal end of the manifold leads to further enhancement. The user may replace the same guidewire or may utilize another guidewire of his choice (“guidewire swapping”). This ability is favorable to physicians since they want as many choices to perform their job to the best of their ability as possible (i.e., beneficial so they do not lose wire position, or that they may want a stiffer or more floppy guidewire to cross a tight stenosis or traverse tortuous anatomy). This enhancement is achieved through simple changes to the manifold, whereby an insert is included for guidewire routing. 
     There is yet another benefit to the asymmetrical design of the present disclosure at the catheter distal end where all of the jet stream outflow is directed from one side of the catheter distal end resulting in a powerful concentration of directed force and increased flow caused by removal or proximal retardation of the guidewire. Such benefit results in the distal portion of the catheter reactingly being directed and forced against the vessel wall opposite to the cross stream action. This movement beneficially keeps the inflow and outflow orifices away from the vessel wall. It has been shown that vessel contact with the inflow or outflow orifices (interior jets, suction, or a combination of both) can cause vessel damage in various degrees. Therefore, this “naked catheter” (i.e., there are other designs having cages or balloons which would keep the jet flow from contacting the walls, but this design uses active jet flow to position the device) design is very safe with respect to vessel wall damage. 
     Some alternatives of this design would use differently shaped orifices, such as slots, instead of holes, etc. Round, oval, elliptical, obround, tapered, slotted, rectangular, triangular, rounded corner, protruding, or multiple-radius configurations can be utilized for the inflow and/or outflow orifices, where the orifices could be shaped such as to direct the flow in a preferred direction. 
     The catheter body could also be shaped to maximize the effectiveness of the flow. Also, the body of the catheter at the distal end may include a 180.degree. reversal where the reversed distal end is utilized to aid in removing material from the vessel wall. The effectiveness of the catheter could also be increased by increasing the flow to the catheter tip, which would impart more energy to the system to do work. 
     There is an alternative design that is similar in principle to the first embodiments of the present disclosure but which uses a physical barrier to deflect the flow out the side outflow orifice. In the current cross stream designs, a static or slow moving column of fluid captures the energy from the high velocity fluid jets resulting in a recovered pressure near the side outflow orifices. This recovered pressure drives fluid out the side outflow orifices. The general principle is that the velocity fluid jets entrain surrounding fluid which enters the catheter from the side inlet orifices. This excess fluid must exit the catheter since the outflow rate of the catheter is balanced to equal the infused flow rate from a suction source, such as a pump. As a result, higher recovered pressure near the side outflow orifices, which generates the recirculating flow pattern at the catheter tip, is seen. There are a number of fluid mechanical inefficiencies associated with such a design. Primarily, the strong high velocity fluid jets end up traveling down past the side outflow orifices and eventually break up into large turbulent eddies. Guiding the flow out a side outflow orifice can preserve some of this energy rather than having it consumed by turbulence inside the catheter. Another alternative design is incorporated to implement waste flow removal by orienting most of the high velocity fluid jets forward and then deflecting them out the distal end of the catheter where a small number of proximal-facing high velocity fluid jets are utilized to drive outflow from the catheter. The other alternative is to apply a roller pump driven waste line to the guide catheter itself and use the roller pump negative pressure to evacuate the waste flow while the deflecting catheter is infusing flow into the patient. 
     SUMMARY 
     The general purpose of the present disclosure is to provide an enhanced cross stream mechanical thrombectomy catheter with backloading manifold. The enhanced cross stream mechanical thrombectomy catheter with backloading manifold is capable of traditional loading over the proximal end of a guidewire or accommodational backloading of the distal end of a guidewire, such as would be useful during an exchange of guidewires whether during or prior to a thrombectomy procedure. Loading of a guidewire through the proximal end of the backloading manifold is accommodated and facilitated by a self-sealing arrangement including a hemostatic nut and a seal at the proximal end of the backloading manifold and by a tubular insert centrally located along the interior of the tubular central body of the backloading manifold. The insert includes a proximally-facing beveled surface entrance leading to an integral and distally located central passageway which extends along the greater portion of the length of the insert where such proximally-facing beveled surface entrance is useful for directing and loading a guidewire (i.e., a proximally loaded and distally directed guidewire) which is first directed in a central direction by the proximally-facing beveled surface entrance followed by passage through the central passageway. The distal and truncated portion of the insert central passageway connects to the proximal end of a catheter tube composed of a braided catheter tube successively connected to a plastic smooth catheter tube leading to an integral flexible and tapered distal tip at the distal portion of the smooth catheter tube. The geometry of a fluid jet emanator and related structure near the distal tip of the smooth catheter tube assists and promotes passage of a guidewire passing in either direction through the fluid jet emanator and related structure. 
     Cross stream flow at the distal portion of the smooth catheter tube as produced by a fluid jet emanator is enhanced by the use of one outflow orifice and one inflow orifice, thereby allowing concentration and intensity of the cross stream flow to provide only one localized region of thrombus ablation. Such ablation flow creates forces urging the distal portion of the plastic catheter tube away from the ablation area (i.e., away from the cross stream flow) in order that the vascular walls are not blockingly engaged by the inflow orifice. Such distancing is also helpful in keeping the cross stream flow from being dangerously close to the vascular wall, thereby minimizing the possibility of vascular wall damage. 
     According to one or more embodiments of the present disclosure, there is provided an enhanced cross stream mechanical thrombectomy catheter with backloading manifold, including a backloading manifold having an exhaust branch and a high pressure connection branch extending from a tubular central body of the backloading manifold, a hemostatic nut threadingly secured to the proximal portion of a proximal cavity body of the backloading manifold, a tubular insert located in an insert cavity of the backloading manifold, a strain relief extending distally from a distal manifold extension of the backloading manifold, a catheter tube formed in part of a braided catheter tube being connected to the insert and extending through the strain relief and in part of a plastic smooth catheter tube successively connected to the braided catheter tube, an inflow and an outflow orifice spaced longitudinally along one side of and located near the proximal end of the plastic smooth catheter tube, an integral flexible tip at the distal end of the plastic smooth catheter tube, and a high pressure tube extending through the high pressure connection branch, through portions of the backloading manifold, partially through the insert, and through the catheter tube composed of the braided catheter tube and plastic smooth catheter tube to terminate as a fluid jet emanator near the distal portion of the plastic smooth catheter tube where such termination is distal of the inflow and the outflow orifices, as well as other components described herein. 
     One significant aspect and feature of embodiments of the present disclosure include an enhanced cross stream mechanical thrombectomy catheter with backloading manifold with enhanced efficacy due to concentration of all the flow to one set of inflow and outflow orifices with a guidewire in place. 
     Another significant aspect and feature of embodiments of the present disclosure include an enhanced cross stream mechanical thrombectomy catheter with backloading manifold with even greater enhanced efficacy due to concentration of all the flow to one set of inflow and outflow orifices with the removal, retarding or other positioning of a guidewire. 
     Yet another significant aspect and feature of embodiments of the present disclosure include an enhanced cross stream mechanical thrombectomy catheter with backloading manifold that utilizes the position of the high pressure tube in relation to the outflow and inflow orifices to enable a guidewire to move freely in and out of the catheter tube without going out one of the orifices. 
     Still another significant aspect and feature of embodiments of the present disclosure include an enhanced cross stream mechanical thrombectomy catheter with backloading manifold that has a specially designed insert that allows a guidewire to be completely removed and replaced or exchanged for another desired guidewire. 
     Another significant aspect and feature of embodiments of the present disclosure include an enhanced cross stream mechanical thrombectomy catheter with backloading manifold that can be safer than other cross stream designs since the outflow orifice flow pushes the distal catheter end containing the inflow orifice and the outflow orifice away from the vessel wall (the region were damage can occur), thereby minimizing the possibility of blood vessel wall ingestion by the inflow orifice. 
     Another significant aspect and feature of embodiments of the present disclosure include an enhanced cross stream mechanical thrombectomy catheter with backloading manifold that employs many of the above significant aspects and features plus additionally including a catheter having a reversed distal end incorporated to intimately contact and remove grumous material from a vessel wall by direct abrading contact and by cross stream flow ablation. 
     Another significant aspect and feature of embodiments of the present disclosure include an enhanced cross stream mechanical thrombectomy catheter with backloading manifold that employs many of the above significant aspects and features and has inflow and outflow orifices shaped or sized to give optimal flow direction or performance. 
     Another significant aspect and feature of embodiments of the present disclosure include an enhanced cross stream mechanical thrombectomy catheter with backloading manifold that employs many of the above significant aspects and features and wherein the efficacy can be increased by increasing flow to the jet orifices (i.e., currently 60 cc of fluid delivered per minute . . . increased to 100 cc/min). 
     Another significant aspect and feature of embodiments of the present disclosure include an enhanced cross stream mechanical thrombectomy catheter with backloading manifold that employs deflection for concentrating and redirecting high velocity fluid jets to form cross stream jets with or without exhaust as an alternative design. 
     Another significant aspect and feature of embodiments of the present disclosure include an enhanced cross stream mechanical thrombectomy catheter with backloading manifold that can operate in a pressure range of 100 to 20,000 psi. 
     Yet another significant aspect and feature of embodiments of the present disclosure are the use of additional outflow orifices and inflow orifices in angular off-center opposition to the main outflow orifice and the inflow orifice. 
     Having thus described embodiments of the present disclosure and set forth significant aspects and features of embodiments of the present disclosure, it is the principal object of the present disclosure to provide an enhanced cross stream mechanical thrombectomy catheter with backloading manifold. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other objects of the present disclosure and many of the attendant advantages of embodiments of the present disclosure 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  is an isometric view of an enhanced cross stream mechanical thrombectomy catheter with backloading manifold, the present disclosure; 
         FIG. 2  is an isometric exploded view of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold; 
         FIG. 3  is an exploded cross section side view of the components of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold; 
         FIG. 4  is an isometric view of the insert showing an elongated slot extending through the main body; 
         FIG. 5  is a cross section view of the assembled elements of  FIG. 3 ; 
         FIG. 6  is a cross section view of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold along line  6 - 6  of  FIG. 5 ; 
         FIG. 7  is a bottom view of the distal end of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold showing the smooth catheter tube, the outflow orifice, and the inflow orifice, as well as the high pressure tube visible through the outflow orifice and the inflow orifice; 
         FIG. 8  is an isometric view of the fluid jet emanator; 
         FIG. 9  is a side view in cross section along line  9 - 9  of  FIG. 8  of the fluid jet emanator; 
         FIG. 10  is a side view in cross section illustrating the elements of  FIG. 9  secured in the distal portion of the smooth catheter tube by a radiopaque marker band, as well as showing the cross stream flow; 
         FIG. 11  is a side view of the distal region of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold showing the distal end of a smooth catheter tube assembly positioned in a blood vessel (shown in cross section) at a site of a thrombotic deposit or lesion; 
         FIG. 12  is a side view in cross section illustrating the introduction of a guidewire into the enhanced cross stream mechanical thrombectomy catheter with backloading manifold; 
         FIG. 13 , a first alternative embodiment, is an isometric view of an enhanced cross stream mechanical thrombectomy catheter with backloading manifold; 
         FIG. 14  is a partially exploded isometric view of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold illustrated in  FIG. 13 ; 
         FIG. 15  is a cross section side view of the components of the distal region of the smooth catheter tube assembly along line  15 - 15  of  FIG. 13 ; 
         FIG. 16  is a magnified cross section view along line  16 - 16  of  FIG. 15 ; 
         FIG. 17  is a cross section view of the smooth catheter tube assembly along line  17 - 17  of  FIG. 16 ; 
         FIG. 18  illustrates the distal portion of the smooth catheter tube assembly of the first alternative embodiment in cross section; 
         FIG. 19  is a side view of the distal region of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold constituting the first alternative embodiment showing the distal end of the smooth catheter tube assembly positioned in a blood vessel (shown in cross section) at a site of a thrombotic deposit or lesion; 
         FIG. 20 , a second alternative embodiment, is an isometric view of an enhanced cross stream mechanical thrombectomy catheter with backloading manifold; 
         FIG. 21  is a partially exploded isometric view of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold illustrated in  FIG. 20 ; 
         FIG. 22  is a cross section side view of the components of the distal region of the smooth catheter tube assembly along line  22 - 22  of  FIG. 20 ; 
         FIG. 23  is a magnified cross section view along line  23 - 23  of  FIG. 22 ; 
         FIG. 24  is a cross section view of the smooth catheter tube assembly along line  24 - 24  of  FIG. 23 ; 
         FIG. 25  illustrates the distal portion of the smooth catheter tube assembly of the second alternative embodiment in cross section; 
         FIG. 26  is a side view of the distal region of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold constituting the second alternative embodiment showing the distal end of the smooth catheter tube assembly positioned in a blood vessel (shown in cross section) at a site of a thrombotic deposit or lesion; 
         FIG. 27 , a third alternative embodiment, is an isometric view of an enhanced cross stream mechanical thrombectomy catheter with backloading manifold including a smooth catheter tube which is curved; 
         FIG. 28  is a partially exploded isometric view of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold illustrated in  FIG. 27 ; 
         FIG. 29  is a cross section side view of the components of the distal region of the smooth catheter tube assembly along line  29 - 29  of  FIG. 27 ; 
         FIG. 30  is a side view of the distal region of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold constituting the third alternative embodiment at a thrombus site; 
         FIG. 31  is a cross section view along line  31 - 31  of  FIG. 30 ; 
         FIG. 32 , a fourth alternative embodiment, is a side view of a smooth catheter tube having an alternate shape outflow orifice; 
         FIG. 33 , a fifth alternative embodiment, is a view of the distal portion of an alternatively provided smooth catheter tube assembly incorporating the components of the smooth catheter tube assembly shown in the first embodiment and including additional outflow orifices and inflow orifices in angular off-center opposition to the main outflow orifice and the main inflow orifice; 
         FIGS. 34 a  and 34 b    are cross section views through the outflow orifices and inflow orifices of the smooth catheter tube assembly along lines  34   a - 34   a  and  34   b - 34   b  of  FIG. 33  showing cross stream jet flow regions; 
         FIG. 35  is a side view in cross section like  FIG. 10  wherein the distal portion of the smooth catheter tube additionally includes an outflow orifice and an inflow orifice; and, 
         FIG. 36  is a side view of the distal region of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold constituting the fifth alternative embodiment showing the distal end of the smooth catheter tube assembly positioned in a blood vessel-shown in cross section at a site of a thrombotic deposit or lesion. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  is an isometric view of an enhanced cross stream mechanical thrombectomy catheter with backloading manifold  10 . Externally visible major components of an embodiment of the present disclosure include a centrally located backloading manifold  12 , a hemostatic nut  14  threadingly secured to the backloading manifold  12 , an introducer  15 , a flexible and tapered strain relief  16  connected to and extending from the backloading manifold  12 , a catheter tube composed of a braided catheter tube  18  of flexible or semi-flexible material, preferably polyimide or other such suitable composition, connected to the backloading manifold  12  and extending through the tapered and flexible strain relief  16  and a smooth catheter tube assembly  19  having a smooth catheter tube  20  of plastic composition connected to and extending distally from the braided catheter tube  18 , and an outflow orifice  22  and an inflow orifice  24  located in longitudinal alignment along an imaginary line at the distal portion of the smooth catheter tube  20  near a flexible tapered tip  26  located distally at the end of the smooth catheter tube  20 . The components of the smooth catheter tube assembly  19  are depicted fully in  FIGS. 2 and 3 . For illustration purposes, the outflow orifice  22  and the inflow orifice  24 , which extend through the smooth catheter tube  20 , are shown on the side of the smooth catheter tube  20 , but can be located along any imaginary line extending longitudinally along a distal surface of the smooth catheter tube  20 , such as is shown in  FIGS. 3, 7, 10 and 11 . Normally, the catheter tube  18  is formed as a braided construction for strength, as shown, but it can be effectively formed in other ways: for example, by using reinforcing components such as fibers, wound strands, rings, wraps, or combinations thereof. Other externally visible major components include a radiopaque marker band  28  located on the smooth catheter tube  20  in close proximity to and proximal to the outflow orifice  22 , a radiopaque marker band  30  located on the smooth catheter tube  20  in close proximity to and distal to the inflow orifice  24 , a high pressure connection branch  32  extending from the central body  34  of the backloading manifold  12 , an exhaust branch  36  extending from the junction of the central body  34  of the backloading manifold  12  and the high pressure connection branch  32 , and a high pressure connector  64  engaging with and extending from the high pressure connection branch  32  of the backloading manifold  12 . An orifice  65  located in the high pressure connection branch  32  allows for the introduction of adhesive  61  ( FIG. 5 ) to secure the high pressure connector  64  in the high pressure connection branch  32 . 
       FIG. 2  is an isometric exploded view of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  10 , and  FIG. 3  is an exploded cross section side view of the components of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  10 . 
     The backloading manifold  12  includes the central body  34  which is tubular and has on one end a proximally located cavity body  38  including an externally located threaded surface  40  and on the other end a distally located tubular manifold extension  42 , including an orifice  41  which is utilized to introduce adhesive  43  ( FIG. 5 ) to secure the proximal end of the braided catheter tube  18  to the distal manifold cavity  56 . A multi-radius insert cavity  44  is continuously co-located within the central body  34  and a portion of the adjacent cavity body  38 . The multi-radius insert cavity  44  is comprised of an elongated distal insert cavity portion  46  located coaxially within the central body  34  adjacent to and connecting to a proximal insert cavity portion  48  located coaxial to the cavity body  38  in continuous fashion. The insert cavity  44  accommodates an insert  50 . A proximal manifold cavity  52  is located coaxially within the cavity body  38  and is continuous with and proximal to the proximal insert cavity portion  48  and an annular cavity wall  54  and an annular and planar surface  55  located between the annular cavity wall  54  and the proximal insert cavity portion  48 . The manifold extension  42  extending distally from the distal end of the backloading manifold  12  includes an inwardly located distal manifold cavity  56  for passage of the proximal end of the braided catheter tube  18 . The exterior of the manifold extension  42  accommodates the strain relief  16 . The strain relief  16  is of flexible construction and includes a proximally located strain relief mounting cavity  58  connected to a passageway  60  both of which extend along the longitudinal axis of the strain relief  16 . The strain relief mounting cavity  58  accommodates the manifold extension  42 , which can be appropriately secured therein, such as by adhesive or mechanical interference. The high pressure connection branch  32  includes a high pressure connection branch passageway  62  intersecting and communicating with the distal insert cavity portion  46  of the insert cavity  44 , as well as offering accommodation of the threaded high pressure connector  64 . A ferrule  66  having a central bore  70  is accommodated by the lumen  67  of the high pressure connector  64 . One end of a high pressure tube  71  is accommodated by and sealingly secured to the central bore  70  of the ferrule  66 , such as by a weldment or mechanical interference. An exhaust branch passageway  72  central to the exhaust branch  36  communicates with the high pressure connection branch passageway  62  and with the distal insert cavity portion  46  of the insert cavity  44 . The exhaust branch  36  has a threaded surface  63  at its end for attaching to suction apparatus. The entire insert  50  is accommodated by the insert cavity  44  where the distal insert cavity portion  46  and the proximal insert cavity portion  48  fittingly accommodate separate geometric configurations of the insert  50 . 
     As also shown in the isometric view of  FIG. 4 , the insert  50  includes a tubular main body  74  having a proximally located shoulder  76  which can be tapered or of other suitable geometric configuration. The shoulder  76  engages an annular transition stop surface  78  ( FIG. 3 ) between the proximal insert cavity portion  48  and the distal insert cavity portion  46 . One end of a central passageway  80  truncatingly intersects an elongated slot  82 ; and such central passageway also intersects a bore  84  which is also truncated by intersecting the elongated slot  82 , i.e., the central passageway  80  adjoins bore  84  and each is truncated by intersection with the elongated slot  82 . The elongated slot  82  extends through the main body  74  to intersect and align to a portion of the longitudinal axis of the insert  50 . The elongated slot  82  accommodates passage of the high pressure tube  71 , as shown in  FIG. 5 . The central passageway  80  has a proximally located beveled surface entrance  86  resembling a cone. The beveled surface entrance  86  is utilized for guidance and alignment for backloading of a guidewire through the backloading manifold  12 , as later described in detail. 
     Beneficial to an embodiment of the present disclosure is the use of a self-sealing hemostatic valve  88 , flanking washers  90  and  92 , and an introducer  15  which are related to a patent application entitled “Thrombectomy Catheter Device Having a Self-Sealing Hemostatic Valve,” U.S. Pat. No. 7,226,433. The self-sealing hemostatic valve  88 , which is slightly oversized with respect to the proximal manifold cavity  52 , and the washers  90  and  92  are aligned in and housed in the proximal manifold cavity  52  at one end of the backloading manifold  12 . The hemostatic nut  14  includes a centrally located cylindrical boss  94 , a central passageway  96  having a beveled surface entrance  97  extending through and in part forming the cylindrical boss  94 , and internal threads  98 . The internal threads  98  of the hemostatic nut  14  can be made to engage the threaded surface  40  of the backloading manifold  12 , whereby the cylindrical boss  94  is brought to bear against the washer  90  to resultantly bring pressure to bear as required against the self-sealing hemostatic valve  88  and washer  92 . The washers  90  and  92  and the self-sealing hemostatic valve  88  are captured in the proximal manifold cavity  52  by threaded engagement of the hemostatic nut  14  to the cavity body  38  of the backloading manifold  12 . Also included in the hemostatic nut  14  is an annular lip  100  which can be utilized for snap engagement of particular styles or types of introducers, as required, such as introducer  15  provided to aid in accommodation of a guidewire in either direction and to provide for venting for the interior of the backloading manifold  12 . The introducer  15  includes a centrally located shaft  102  with a central passageway  103  having a beveled surface entrance  105 , an actuating handle  104 , and rings  106  and  108  about the shaft  102 . Also shown in  FIG. 3  is a lumen  110  central to the braided catheter tube  18  which joiningly connects to and communicates with a lumen  112  central to the smooth catheter tube  20 . A circular support ring  114  is suitably attached to the high pressure tube  71 , such as by a weldment, and is located within the smooth catheter tube  20  in supporting alignment with the radiopaque marker band  28 . A fluid jet emanator  116  including terminated loop  117  at the distal end of the high pressure tube  71  and a circular support ring  124  is located distal of the inflow orifice  24  within the distal end of the smooth catheter tube  20  in alignment with the radiopaque marker band  30 , as later shown in detail in  FIG. 10 . The circular support rings  114  and  124  together with the respective associated radiopaque marker bands  28  and  30  constitute means for retaining the high pressure tube  71  in alignment with the catheter tube composed of braided catheter tube  18  and the smooth catheter tube  20 . 
       FIG. 4  is an isometric view of the insert  50  showing the elongated slot  82  extending through the main body  74  in intersection with the central passageway  80  and the bore  84 . The elongated slot  82  is beneficial for accommodation of the high pressure tube  71 , as well as for communication between the combined lumens  110  and  112  of the braided catheter tube  18  and the smooth catheter tube  20 , respectively, and the high pressure connection branch passageway  62  and the exhaust branch passageway  72 , as shown in  FIG. 5 . 
       FIG. 5  is a cross section view of the assembled elements of  FIG. 3 . Particularly shown is the relationship of the high pressure tube  71 , the insert  50 , the lumen  110  of the braided catheter tube  18 , and the proximal end of the braided catheter tube  18 . The proximal portion of the high pressure tube  71  extends distally from the ferrule  66  through the high pressure connection branch passageway  62 , through the elongated slot  82  of the insert  50  while traversing the distal portion of the central passageway  80  en route to and into the lumen  110  of the braided catheter tube  18 , and thence along the lumen  110  and into the lumen  112  of the smooth catheter tube  20  to terminate as part of the fluid jet emanator  116  shown adjacent to the flexible tapered tip  26  at the distal end of the smooth catheter tube  20 . In addition to providing a passage for the high pressure tube  71 , the elongated slot  82  allows communication between the lumen  110  of the braided catheter tube  18  and the lumen  112  of the smooth catheter tube  20 , collectively, and the high pressure connection branch passageway  62  and the exhaust branch passageway  72  for evacuation of effluence therefrom. Also shown is the junction  118  between the smooth catheter tube  20  and the braided catheter tube  18 , such junction being suitably effected to provide for a smooth and continuous coupling of the smooth catheter tube  20  and the braided catheter tube  18 . 
       FIG. 6  is a cross section view of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  10  along line  6 - 6  of  FIG. 5 . Shown in particular is the elongated slot  82  through which the high pressure tube  71  passes (passage of high pressure tube  71  not shown) and through which communication takes place between the lumen  110  of the braided catheter tube  18  and the high pressure connection branch passageway  62  and the exhaust branch passageway  72 . Also shown is a lumen  120  central to the high pressure tube  71 . 
       FIG. 7  is a bottom view of the distal end of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  10  showing the smooth catheter tube  20  and the outflow orifice  22  and the inflow orifice  24 , as well as the high pressure tube  71  visible through the outflow orifice  22  and the inflow orifice  24 . 
       FIG. 8  is an isometric view and  FIG. 9  is a side view in cross section along line  9 - 9  of  FIG. 8  of the fluid jet emanator  116 . The fluid jet emanator  116  includes a terminated loop  117  at the distal end of the high pressure tube  71  and includes the support ring  124 . The terminated loop  117  includes a plurality of proximally directed jet orifices  122   a - 122   n . The support ring  124  suitably secures to the distal surface of the terminated loop  117  such as by a weldment. A center void  126  of the terminated loop  117  allows for passage of a guidewire or other suitable devices. The support ring  124 , a tubular device, includes a central passageway  128  corresponding in use to that of the center void  126  of the terminated loop  117  for passage of a guidewire or other suitable devices. A distally located annular shoulder  130  on the support ring  124  allows for the inclusion of a beveled annular surface  132  juxtaposing the central passageway  128  to aid in the guided accommodation of a guidewire or other suitable device at the distal portion of the central passageway  128 . A wide annular groove  134  is formed between the annular shoulder  130  and the distally facing surface of the terminated loop  117  and the smaller radiused body of the support ring  124 . The wide annular groove  134  is utilized to secure the fluid jet emanator  116  at a suitable location in the distal portion of the smooth catheter tube  20 , as shown in  FIG. 10 . 
     Mode of Operation 
     The mode of operation of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  10  is explained with reference to  FIGS. 10, 11 and 12 .  FIG. 10  illustrates the elements of  FIG. 9  secured in the distal portion of the smooth catheter tube  20  by the radiopaque marker band  30  which forces an annular portion of the smooth catheter tube  20  into the wide annular groove  134  formed by the support ring  124  and the terminated loop  117  of the fluid jet emanator  116 . High velocity fluid jets  136   a - 136   n  are shown emanating proximally from the plurality of jet orifices  122   a - 122   n  into the lumen  112  of the smooth catheter tube  20  for subsequent creation of and culminating in cross stream jets  140   a - 140   n , as depicted by heavy lines, which flow from the outflow orifice  22  and return through the inflow orifice  24  for ablative action with thrombus material and for maceration of foreign material in concert with the high velocity fluid jets  136   a - 136   n  and or for exhausting proximally with the flow within the distal portion of the smooth catheter tube  20 . A guidewire  141  is also shown in see-through depiction, including alternate guidewire end positions  141   a  and  141   b  designated by dashed lines, where the guidewire  141  extends along the lumen  112  of the smooth catheter tube  20 , through the center void  126  of the terminated loop  117 , and through the central passageway  128  of the support ring  124  into the proximal portion of the flexible tapered tip  26 . Guidewire  141  can be advanced beyond the flexible tapered tip  26  of the smooth catheter tube  20  such as during positioning of the catheter within the blood vessel or other body cavity, and then withdrawn to alternate guidewire end positions  141   a  and  141   b , or other positions within the smooth catheter tube  20 , or withdrawn completely from the smooth catheter tube  20 . An advantage of an embodiment of the present disclosure is that the guidewire  141  can be introduced by a front loading approach or by a backloading approach and, therefore, can be removed and reintroduced or can be replaced by a different guidewire. 
       FIG. 11  is a side view of the distal region of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  10  showing in particular the distal end of the smooth catheter tube assembly  19  positioned in a blood vessel  142  (shown in cross section) at a site of a thrombotic deposit or lesion  144 . While  FIG. 11  depicts the smooth catheter tube assembly  19  as being in a blood vessel in particular, it is to be understood that it is not limited to use in a blood vessel but has utility with respect to any body cavity in general. High velocity fluid jets  136   a - 136   n  (shown in  FIG. 10 ) of saline or other suitable solution are emanated or emitted in a proximal direction from the fluid jet emanator  116  into the smooth catheter tube  20  and pass through the outflow orifice  22  creating cross stream jets  140   a - 140   n  directed toward the wall of the blood vessel  142  having thrombotic deposits or lesions  144  and thence are influenced by the low pressure at the inflow orifice  24  to cause the cross stream jets  140   a - 140   n  to be directed distally substantially parallel to the central axis of the blood vessel  142  to impinge and break up thrombotic deposits or lesions  144  and to, by entrainment, urge and carry along the dislodged and ablated thrombotic particulates  146  of the thrombotic deposits or lesions  144  through the inflow orifice  24 , a relatively low pressure region, and into the lumen  112 , which functions as a recycling maceration lumen or chamber and also as an exhaust lumen. The entrainment through the inflow orifice  24  is based on entrainment by the high velocity fluid jets  136   a - 136   n . The outflow is driven by internal pressure which is created by the high velocity fluid jets  136   a - 136   n  and the fluid entrained through the inflow orifice  24 . The enhanced clot removal is enabled because of the recirculation pattern established between inflow and outflow orifices  22  and  24 , which creates a flow field that maximizes drag force on wall-adhered thrombus, and because of impingement of the cross stream jets  140   a - 140   n . The cross stream jets  140   a - 140   n , whilst being forcefully directed outwardly and toward the wall of the blood vessel  142 , by opposite reaction urge the distal portion of the smooth catheter tube  20  in the direction opposite the outward flow direction and away from the impingement area of the cross stream jets  140   a - 140   n  with the immediate thrombotic deposit or lesion  144  and/or the wall of the blood vessel  142 , thus distancing the highly concentrated high velocity cross stream jets  140   a - 140   n  from the immediate thrombotic deposit or lesion  144  and/or the wall of the blood vessel  142  and thereby minimizing potential blood vessel wall damage. The cross stream jets  140   a - 140   n  traversing between the outflow orifice  22  and the inflow orifice  24  combine to offer an enhanced broad cross section ablation area, such area having a breadth substantially larger and having more concentrated force than prior art devices using multiple inflow and outflow orifices where cross streams are of diminished force and breadth. Having a concentrated flow combining cross stream jets  140   a - 140   n  offers selective and directed ablation to take place. Prior art devices using multiple inflow and outflow orifices and having multiple flow areas generate cross streams which are equally weak in all directions, as the flow force is divided between the multiple flow streams, whereby ablation forces cannot be concentrated where desired. The distal end of the smooth catheter tube  20  can be rotated axially to direct the cross stream jets  140   a - 140   n  about a longitudinal axis to have 360.degree. coverage or can be rotated axially to offer coverage partially about the longitudinal axis, as required. 
     The placement of the guidewire  141  within or the removal of the guidewire  141  from the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  10  influences the operation of an embodiment of the present disclosure. Suitably strong and well directed ablation flow can take place with a guidewire  141  extending the full length of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  10  and/or additionally extending in a distal direction beyond the flexible tapered tip  26  and along the vasculature. Such ablation flow can be further improved, enhanced, modified or otherwise influenced by varying the location of or by full removal of the guidewire  141 . With reference to  FIG. 10 , the guidewire  141 , as shown, allows suitable transition of the high velocity fluid jets  136   a - 136   n  through the outflow orifice  22  to form cross stream jets  140   a - 140   n  which return via the inflow orifice  24 . If, for example, the guidewire  141  is urged proximally to a guidewire end position  141   a  between the inflow orifice  24  and the outflow orifice  22 , the inflow orifice  24  is totally unrestricted and has less flow resistance, thereby allowing greater and more forceful ingress of the cross stream jets  140   a - 140   n  laden with ablated thrombotic particulates  146 , whereas the flow through the outflow orifice  22  remains substantially constant. Urging the guidewire  141  further in a proximal direction to a guidewire end position  141   b  distal to the outflow orifice  22  causes the outflow orifice  22  and the inflow orifice  24  both to be totally unrestricted and both to have less flow resistance, thereby allowing greater and more forceful flow from the outflow orifice  22 , as well as resultantly increased ingress of the cross stream jets  140   a - 140   n  laden with ablated thrombotic particulates  146  through the inflow orifice  24 . Each of the examples given above where the guidewire  141  is not totally removed from the smooth catheter tube  20  or other proximally located regions promotes sustained maceration of the loitering entrained ablated thrombotic particulates  146  where the smaller ablated thrombotic particulates  146  are exhausted proximally through the smooth catheter tube  20 , the braided catheter tube  18 , and the associated and pertinent structure proximal thereto. In another example, urging of the guidewire  141  to a position proximal of the proximal end of the braided catheter tube  18  or total removal of the guidewire  141 , in addition to allowing total unrestricted flow through the outflow orifice  22  and the inflow orifice  24 , allows unrestricted flow of ablated thrombotic particulates  146  along the smooth catheter tube  20 , the braided catheter tube  18 , and the associated and pertinent structure proximal thereto. 
     The preferred embodiment comprises a single outflow orifice  22 , a corresponding cross stream jet which may be split in two by passage around high pressure tube  71 , and a single inflow orifice  24 . 
     Although the preferred embodiment as illustrated incorporates an inflow orifice  24  and an outflow orifice  22  aligned to the high pressure tube  71 , one or both of the inflow or outflow orifices may be located so that they do not align with the high pressure tube; in this case, other means for guiding a guidewire past the orifice(s) is provided to prevent the guidewire from inadvertently passing through the non-aligned orifice(s). 
     The present disclosure also includes methods of treating a body vessel according to the aforementioned mode of operation. 
       FIG. 12  is a side view in cross section illustrating the introduction of the guidewire  141  into the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  10 . When it is desired to remove a guidewire, such as guidewire  141 , or exchange guidewires having different attributes, backloading is facilitated by the structure of the insert  50 . Loading can be accomplished, if necessary, using the introducer  15  to gain entry through the self-sealing hemostatic valve  88  where the introducer parts the sealing structure of the self-sealing hemostatic valve  88  to allow entry of the guidewire  141  therethrough. Otherwise the guidewire can pass unaided through the self-sealing hemostatic valve  88 . The tip of the guidewire may not be in proper alignment with the central passageway  80 , such as is shown by the guidewire  141  shown in dashed lines. In such case, impingement of the tip of the distally urged guidewire  141  with the conically-shaped beveled surface entrance  86  of central passageway  80  directs the tip of the guidewire  141  to align with and to be engaged within the central passageway  80  of the insert  50  and to be in alignment, as shown, within the central passageway  80  so as to align with and be subsequently engaged within the proximal portion of the braided catheter tube  18  for passage therethrough. Distal urging of the guidewire  141  also positions the tip of the guidewire  141  for passage through the distal region of the smooth catheter tube  20  where the geometry helpfully accommodates such passage by and along the outflow orifice  22  and the inflow orifice  24  and through the fluid jet emanator  116 , the support ring  124 , and the flexible tapered tip  26 . Preferably, the tip of the guidewire  141  is dome-shaped. Such a dome shape is easily guided by and accommodated by the proximally-facing rounded surface of the terminated loop  117  of the fluid jet emanator  116 . Use of the introducer  15  can also be utilized if front loading of a guidewire is required for passage through the self-sealing hemostatic valve  88 . Preferably, the guidewire  141  exhibits sufficient size, flexibility and other attributes to navigate the tortuous vascular paths, but exhibits sufficient rigidity not to kink, bend or otherwise be permanently deformed and to stay within the appropriate confines of the distal portion of the smooth catheter tube  20  and not stray through the outflow orifice  22  or the inflow orifice  24 . The cross sections of the outflow orifice  22  and the inflow orifice  24  are such that entry thereinto of the horizontally aligned guidewire of sufficient size and larger cross section profile is next to impossible. Notwithstanding, the use of one pair of inflow and outflow orifices further reduces the chance of inadvertent exiting of the guidewire tip through an orifice. 
     The present disclosure also includes methods of fabricating an enhanced cross stream mechanical thrombectomy catheter with backloading manifold including steps of providing components as disclosed herein and steps of aligning the provided components and steps of affixing the aligned provided components to retain the components in the aligned configuration as indicated in  FIGS. 5, 7 and 10 . 
       FIG. 13 , a first alternative embodiment, is an isometric view of an enhanced cross stream mechanical thrombectomy catheter with backloading manifold  210 , incorporating much of the structure previously described, but differing in the substitution of a smooth catheter tube assembly  212  and other components and structure housed in the smooth catheter tube assembly  212  for the smooth catheter tube assembly  19  and previously described components and structure housed in the smooth catheter tube assembly  19 . Also, previously described components are utilized including the components of or components attached to or associated with the centrally located backloading manifold  12  involving the hemostatic nut  14 , the introducer  15 , the flexible and tapered strain relief  16 , and the braided catheter tube  18 . The smooth catheter tube assembly  212  of multiple layer plastic composition is connected to and extends distally from the braided catheter tube  18  at a junction  118   a  and includes an outflow orifice  214 , an inflow orifice  216 , and additionally an evacuation orifice  218 , each located in longitudinal alignment along an imaginary line at the distal portion of the smooth catheter tube assembly  212  near a flexible tapered tip  220  located distally at the end of the smooth catheter tube assembly  212  and each extending through the wall of the smooth catheter tube  224 . For illustration purposes, the outflow orifice  214 , the inflow orifice  216 , and the evacuation orifice  218  are shown on the side of the smooth catheter tube assembly  212 , but they can be located along any imaginary line extending longitudinally along a distal surface of the smooth catheter tube assembly  212 , such as is shown in  FIGS. 15 and 18 . 
       FIG. 14  is a partially exploded isometric view of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  210 ;  FIG. 15  is a cross section side view of the components of the distal region of the smooth catheter tube assembly  212  along line  15 - 15  of  FIG. 13 ; and  FIG. 16  is a magnified cross section view along line  16 - 16  of  FIG. 15 . With reference to  FIGS. 14, 15 and 16 , the first alternative embodiment is now further described. 
     The smooth catheter tube assembly  212 , the components of which are depicted fully in  FIGS. 13 and 14 , includes a centrally located smooth catheter tube  224 , having lumens  222   a  and  222   b , about which or in which other components are located, including a guidewire tube  228  having a lumen  230  which aligns preferably in opposition to the outflow orifice  214 , the inflow orifice  216 , and the evacuation orifice  218  along the opposing outer surface of the smooth catheter tube  224  and which extends along the smooth catheter tube  224  from and including the flexible tapered tip  220  to enter and pass within the lumen  110  of the braided catheter tube  18  at or near the junction  118   a  to the interior of the backloading manifold  12 . A flexible plastic sheath  232 , part of the smooth catheter tube assembly  212 , encompasses the smooth catheter tube  224  and extends the length thereof from the flexible tapered tip  220  until reaching the junction  118   a . The proximal portion of the high pressure tube  71  extends distally and through the lumen  110  of the braided catheter tube  18 , and thence along the lumen  222   a  of and along the smooth catheter tube  224  to terminate as part of the fluid jet emanator  116  shown in  FIG. 15  adjacent to the flexible tapered tip  220  at the distal end of the lumen  222   b  of the smooth catheter tube assembly  212 . A deflector  234  in the form of a truncated solid structure and including a deflector face  236  suitably angled with respect to the longitudinal axis of the smooth catheter tube  224  is located between the lumens  222   a  and  222   b  of the smooth catheter tube  224  and defines the separation of the lumens  222   a  and  222   b  where lumen  222   a  extends proximally along the interior of the smooth catheter tube  224  from the deflector  234  in communication with the evacuation orifice  218  and where the lumen  222   b  extends distally from the deflector  234  in communication with the outflow orifice  214  and the inflow orifice  216  until terminating at the flexible tapered tip  220 . The deflector  234  is located in close proximity to the outflow orifice  214  and is oriented to cause the deflection of the highly pressurized fluid jets projected proximally from the fluid jet emanator  116  to be reflectingly and deflectingly directed through the outflow orifice  214 , as described later in detail. The deflector  234  aids in structural integrity of the distal portion of the smooth catheter tube  224  as does the structure of the fluid jet emanator  116 . Also shown in  FIG. 14  is the junction  118   a  between the smooth catheter tube assembly  212  and the braided catheter tube  18 , such junction being suitably effected to provide for a smooth and continuous coupling of the smooth catheter tube assembly  212  and the braided catheter tube  18 . 
       FIG. 17  is a cross section view of the smooth catheter tube assembly  212  along line  17 - 17  of  FIG. 16 . Shown in particular is an elongated slot  238  extending longitudinally through the upper surface of the deflector  234  through which the high pressure tube  71  passes and secures such as by welding or other suitable means. Also shown is the sheath  232  surroundingly encompassing the smooth catheter tube  224  and the guidewire tube  228 , thereby securing the guidewire tube  228  to the smooth catheter tube  224 . 
     Mode of Operation 
     The mode of operation of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  210  is explained with reference to  FIGS. 18 and 19 .  FIG. 18  illustrates the distal portion of the smooth catheter tube assembly  212  in cross section and the use of a vacuum source, such as a vacuum pump or roller pump  239 , which connects through the lumen  222   a  of the smooth catheter tube  224  to the exhaust branch  36  of the backloading manifold  12 . High velocity fluid jets  240   a - 240   n  are shown emanating proximally from the plurality of jet orifices  122   a - 122   n  of the terminated loop  117  of the fluid jet emanator  116  into the lumen  222   b  of the smooth catheter tube  224  for subsequent creation of and culminating in cross stream jets  242   a - 242   n , shown by heavy lines, where the high velocity fluid jets  240   a - 240   n  are concentratingly deflected and redirected by the deflector face  236  of the deflector  234  to flow as cross stream jets  242   a - 242   n  from the outflow orifice  214  and return through the inflow orifice  216  while accomplishing ablative action with adhered blood vessel thrombus foreign material and for maceration of foreign material in concert with the high velocity fluid jets  240   a - 240   n . A great preponderance of foreign material is introduced through the inflow orifice  216  and into the lumen  222   b  after dislodging from a blood vessel wall for macerating impingement by the high velocity fluid jets  240   a - 240   n . Macerated small mass foreign material, i.e., thrombotic particulate, contained in the cross stream jets  242   a - 242   n , especially that foreign material near the outflow orifice  214 , is drawn from the flow of the cross stream jets  242   a - 242   n  by the relatively low pressure area presented at the evacuation orifice  218  along an additional and proximally directed flow  244  from the outflow orifice  214  to the evacuation orifice  218  and thence proximally through and within the lumen  222   a  of the smooth catheter tube  224 , as also depicted by heavy lines. A previously placed guidewire (not shown) is incorporated to load the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  210  within the vasculature by first utilizing the distal end of the lumen  230  of the guidewire tube  228  followed by subsequent advancement by the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  210  along the guidewire in close proximity to a thrombus site. In the alternative, the first guidewire can be withdrawn completely from the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  210  and swapped by backloading with another guidewire of other properties and attributes if required. An advantage of an embodiment of the present disclosure is that the guidewire can be introduced by a front loading approach or by a backloading approach and, therefore, the guidewire can be removed and reintroduced or can be replaced by a different guidewire. 
       FIG. 19  is a side view of the distal region of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  210  showing in particular the distal end of the smooth catheter tube assembly  212  positioned in a blood vessel  142  (shown in cross section) at a site of a thrombotic deposit or lesion  144 . While  FIG. 19  depicts the smooth catheter tube assembly  212  as being in a blood vessel in particular, it is to be understood that it is not limited to use in a blood vessel, but has utility with respect to any body cavity in general. High velocity fluid jets  240   a - 240   n  (shown in  FIG. 18 ) of saline or other suitable solution are emanated or emitted in a proximal direction from the fluid jet emanator  116  into the smooth catheter tube  224  and pass through the outflow orifice  214  creating cross stream jets  242   a - 242   n  directed toward the wall of the blood vessel  142  having thrombotic deposits or lesions  144  and thence are influenced by the low pressure at the inflow orifice  216  to cause the cross stream jets  242   a - 242   n  to be directed distally substantially parallel to the central axis of the blood vessel  142  to impinge and break up thrombotic deposits or lesions  144  and to, by entrainment, urge and carry along the dislodged and ablated thrombotic particulate  146  of the thrombotic deposits or lesions  144  through the inflow orifice  216 , a relatively low pressure region, and into the lumen  222   b , which functions as a recycling maceration lumen or chamber or some thrombotic particulate  146  may enter the evacuation orifice  218 . The entrainment through the inflow orifice  216  is facilitated by a low pressure source presented by the high velocity fluid jets  240   a - 240   n . The outflow is driven in part by internal pressure which is created by the high velocity fluid jets  240   a - 240   n , but more generally, outflow drive is caused by the suction (low pressure region) at the evacuation orifice  218  and proximally along lumen  222   a  as provided by the vacuum pump or roller pump  239 . The enhanced clot removal is enabled by of the recirculation pattern established between inflow and outflow orifices  216  and  214 , which creates a flow field that maximizes drag force on wall-adhered thrombus, and because of impingement of the cross stream jets  242   a - 242   n . The cross stream jets  242   a - 242   n , while being forcefully directed outwardly and toward the wall of the blood vessel  142  by opposite reaction, urge the distal portion of the smooth catheter tube  224  in the direction opposite the outward flow direction and away from the impingement area of the cross stream jets  242   a - 242   n  with the immediate thrombotic deposit or lesion  144  and/or the wall of the blood vessel  142 , thus distancing the highly concentrated cross stream jets  242   a - 242   n  from the immediate thrombotic deposit or lesion  144  and/or the wall of the blood vessel  142 , and thereby minimizing potential blood vessel-wall damage. Such distancing also removes the inflow orifice  216  from close proximity with and away from the opposed wall of the blood vessel  142 , thereby minimizing the chance of ingestion of the blood vessel  142  wall structure by the inflow orifice  216 . 
     The cross stream jets  242   a - 242   n  traversing between the outflow orifice  214  and the inflow orifice  216  combine to offer an enhanced broad cross section ablation area, such area having a breadth substantially larger and having more concentrated force than prior art devices using multiple inflow and outflow orifices where cross streams are of diminished force and breadth. Having a concentrated flow combining cross stream jets  242   a - 242   n  offers selective and directed ablation to take place. Prior art devices using multiple inflow and outflow orifices and having multiple flow areas generate cross streams which are equally weak in all directions, as the flow force is divided between the multiple flow streams, whereby ablation forces cannot be concentrated where desired. The distal end of the smooth catheter tube  224  can be rotated axially to direct the cross stream jets  242   a - 242   n  about a longitudinal axis to have 360.degree. coverage or can be rotated axially to offer coverage partially about the longitudinal axis or can be operated to and fro, as required. 
       FIG. 20 , a second alternative embodiment, is an isometric view of an enhanced cross stream mechanical thrombectomy catheter with backloading manifold  310  incorporating much of the structure previously described, especially that of the first alternative embodiment, but differing from the preferred embodiment, as does the first alternative embodiment, by the substitution of, for example, a smooth catheter tube assembly  312  and other components and structure housed in the smooth catheter tube assembly  312  for the smooth catheter tube assembly  212 , and previously described components and structure housed in the smooth catheter tube assembly  212 . Also, previously described components are utilized including the components of or components attached to or associated with the centrally located backloading manifold  12  involving the hemostatic nut  14 , the introducer  15 , the flexible and tapered strain relief  16 , and the braided catheter tube  18 . In the second alternative embodiment, the smooth catheter tube assembly  312  of multiple layer plastic composition is connected to and extends distally from the braided catheter tube  18  at a junction  118   b  and includes an outflow orifice  314 , an inflow orifice  316 , and an evacuation orifice  318 , each located in longitudinal alignment along an imaginary line at the distal portion of the smooth catheter tube assembly  312  near a flexible tapered tip  320  located distally at the end of the smooth catheter tube assembly  312 . For illustration purposes, the outflow orifice  314 , the inflow orifice  316 , and the evacuation orifice  318  which extend through the wall of the smooth catheter tube  324  are shown on the side of the smooth catheter tube assembly  312 , but they can be located along any imaginary line extending longitudinally along a distal surface of the smooth catheter tube assembly  312 , such as is shown in  FIGS. 22 and 25 . 
       FIG. 21  is a partially exploded isometric view of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  310 ;  FIG. 22  is a cross section side view of the components of the distal region of the smooth catheter tube assembly  312  along line  22 - 22  of  FIG. 20 ; and  FIG. 23  is a magnified cross section view along line  23 - 23  of  FIG. 22 . With reference to  FIGS. 21, 22 and 23 , the second alternate embodiment is now further described. 
     The smooth catheter tube assembly  312 , the components of which are depicted fully in  FIGS. 20 and 21 , includes a centrally located smooth catheter tube  324  having lumens  322   a  and  322   b , about which or in which other components are located, including a guidewire tube  328  having a lumen  330  which aligns preferably in opposition to the outflow orifice  314 , the inflow orifice  316 , and the evacuation orifice  318  along the opposing outer surface of the smooth catheter tube  324  and which extends along the smooth catheter tube  324  from and including the flexible tapered tip  320  to enter and pass within the lumen  110  of the braided catheter tube  18  at or near the junction  118   b  to the interior of the backloading manifold  12 . A flexible plastic sheath  332 , part of the smooth catheter tube assembly  312 , encompasses the smooth catheter tube  324  and extends the length thereof from the flexible tapered tip  320  until reaching the junction  118   b . The proximal portion of the high pressure tube  71  extends distally and through the lumen  110  of the braided catheter tube  18 , and thence along the lumen  322   a  of and along the smooth catheter tube  324  to terminate as part of a multidirectional fluid jet emanator  116   a  shown in  FIG. 22 . In this embodiment, the multidirectional fluid jet emanator  116   a  is located between the inflow orifice  316  and the evacuation orifice  318  of the smooth catheter tube  324  and defines the separation of the lumens  322   a  and  322   b  where lumen  322   a  extends proximally along the interior of the smooth catheter tube  324  from the multidirectional fluid jet emanator  116   a  in communication with the evacuation orifice  318  and where the lumen  322   b  extends distally from the multidirectional fluid jet emanator  116   a  in communication with the inflow orifice  316  and the outflow orifice  314  until terminating at a deflector  334  adjacent to the flexible tapered tip  320 . The deflector  334 , in the form of a truncated solid structure and including a deflector face  336  suitably angled with respect to the longitudinal axis of the smooth catheter tube  324 , is located at the distal end of the lumen  322   b  in close proximity and slightly distal of the outflow orifice  314  and is oriented to cause the deflection of the high velocity fluid jets projected distally from the multidirectional fluid jet emanator  116   a  to be reflectingly and deflectingly directed through the outflow orifice  314 , as described later in detail. The deflector  334  aids in structural integrity of the distal portion of the smooth catheter tube  324  as does the structure of the multidirectional fluid jet emanator  116   a . Also shown in  FIG. 21  is the junction  118   b  between the smooth catheter tube assembly  312  and the braided catheter tube  18 , such junction being suitably effected to provide for a smooth and continuous coupling of the smooth catheter tube assembly  312  and the braided catheter tube  18 .  FIG. 23  best illustrates the multidirectional fluid jet emanator  116   a  which is a variation of the previously described fluid jet emanator  116 . The multidirectional fluid jet emanator  116   a  includes features found in the fluid jet emanator  116 , but the terminated loop  117  of the fluid jet emanator  116  is replaced by a proximal loop  117   a , and a connected distal loop  117   b  is added. Both the proximal loop  117   a  and the distal loop  117   b  are in communication with each other and with the high pressure tube  71  and they are located on opposing ends of a support ring  124   a . A plurality of proximally directed jet orifices  123   a - 123   n  are located on the proximal side of the proximal loop  117   a , and a plurality of distally directed jet orifices  125   a - 125   n  are located on the distal side of the distal loop  117   b  for simultaneous emanation of high velocity fluid jets in opposite directions. The multidirectional fluid jet emanator  116   a  is suitably affixed within the smooth catheter tube  324  between the inflow orifice  316  and the evacuation orifice  318 . 
       FIG. 24  is a cross section view of the smooth catheter tube assembly  312  along line  24 - 24  of  FIG. 23 . Shown in particular is the evacuation orifice  318  which passes through both the plastic sheath  332  and the smooth catheter tube  324 . 
     Mode of Operation 
     The mode of operation of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  310  is explained with reference to  FIGS. 25 and 26 .  FIG. 25  illustrates the distal portion of the smooth catheter tube assembly  312  in cross section and the use of an optional vacuum source, such as a vacuum pump or roller pump  339 , which connects through the lumen  322   a  of the smooth catheter tube  324  to the exhaust branch  36  of the backloading manifold  12 . High velocity fluid jets  340   a - 340   n  are shown emanating distally from the plurality of jet orifices  125   a - 125   n  in the distal loop  117   b  of the fluid jet emanator  116  into the lumen  322   b  of the smooth catheter tube  324  for subsequent creation of and culminating in cross stream jets  342   a - 342   n , as shown by heavy lines, where the high velocity fluid jets  340   a - 340   n  are concentratingly deflected and redirected by the deflector face  336  of the deflector  334  to flow as cross stream jets  342   a - 342   n  from the outflow orifice  314  and return through the inflow orifice  316  while accomplishing ablative action with adhered blood vessel thrombus foreign material and for maceration of foreign material in concert with the high velocity fluid jets  340   a - 340   n . A great preponderance of foreign material is introduced through the inflow orifice  316  and into the lumen  322   b  after dislodging from a blood vessel wall for macerating impingement by the high velocity fluid jets  340   a - 340   n . Macerated small mass foreign material, i.e., thrombotic particulate, contained in the cross stream jets  342   a - 342   n , especially that foreign material near the inflow orifice  316 , is drawn from the flow of the cross stream jets  342   a - 342   n  by the relatively low pressure area presented at the evacuation orifice  318  along an additional and proximally directed flow  344  from near the inflow orifice  316  to the evacuation orifice  318  and thence proximally through and within the lumen  322   a  of the smooth catheter tube  324 , as also depicted by heavy lines. Proximally directed high velocity fluid jets  346   a - 346   n  emanating proximally from the plurality of jet orifices  123   a - 123   n  in the proximal loop  117   a  into the lumen  322   a  of the smooth catheter tube  324  create the relatively low pressure presented at the evacuation orifice  318  to draw thrombotic particulate through the evacuation orifice  318  and to provide a proximally directed driving force to urge the thrombotic particulate proximally along the lumen  322   a.    
     A previously placed guidewire (not shown) is incorporated to load the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  310  within the vasculature by first utilizing the distal end of the lumen  330  of the guidewire tube  328  followed by subsequent advancement by the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  310  along the guidewire in close proximity to a thrombus site. In the alternative, the first guidewire can be withdrawn completely from the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  310  and swapped by backloading with another guidewire of other properties and attributes, if required. An advantage of an embodiment of the present disclosure is that the guidewire can be introduced by a front loading approach or by a backloading approach and, therefore, the guidewire can be removed and reintroduced or can be replaced by a different guidewire. 
       FIG. 26  is a side view of the distal region of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  310  showing in particular the distal end of the smooth catheter tube assembly  312  positioned in a blood vessel  142  (shown in cross section) at a site of a thrombotic deposit or lesion  144 . While  FIG. 26  depicts the smooth catheter tube assembly  312  as being in a blood vessel in particular, it is to be understood that it is not limited to use in a blood vessel but has utility with respect to any body cavity in general. High velocity fluid jets  340   a - 340   n  (shown in  FIG. 25 ) of saline or other suitable solution are emanated or emitted in a distal direction from the multidirectional fluid jet emanator  116   a  into the lumen  322   b  of the smooth catheter tube  324  and are concentratingly deflected and redirected by the deflector  334  to pass through the outflow orifice  314  creating cross stream jets  342   a - 342   n  directed toward the wall of the blood vessel  142  having thrombotic deposits or lesions  144  and thence are influenced by the low pressure at the inflow orifice  316  to cause the cross stream jets  342   a - 342   n  to be directed proximally substantially parallel to the central axis of the blood vessel  142  to impinge and break up thrombotic deposits or lesions  144  and to, by entrainment, urge and carry along the dislodged and ablated thrombotic particulate  146  of the thrombotic deposits or lesions  144  through the inflow orifice  316 , a relatively low pressure region, and into the lumen  322   b , which functions as a recycling maceration lumen or chamber, or some thrombotic particulate  146  may enter the evacuation orifice  318 . The entrainment through the evacuation orifice  318  is facilitated by a low pressure source presented by the high velocity fluid jets  346   a - 346   n  directed proximally along the lumen  322   a  for entrainment of thrombotic particulate  146  along the path of the proximally directed flow  344  for ingestion of thrombotic particulate  146  through the evacuation orifice  318 . The outflow is driven by internal pressure which is created by the high velocity fluid jets  346   a - 346   n  proximally directed along the lumen  322   a , but alternatively, the outflow drive can be assisted by the suction (low pressure region) at the lumen  322   a  as provided by the vacuum pump or roller pump  339 . The enhanced clot removal is enabled by the recirculation pattern established between inflow and outflow orifices  316  and  314 , which creates a flow field that maximizes drag force on wall-adhered thrombus, and because of impingement of the cross stream jets  342   a - 342   n . The cross stream jets  342   a - 342   n , while being forcefully directed outwardly and toward the wall of the blood vessel  142  by opposite reaction, urge the distal portion of the smooth catheter tube  324  in the direction opposite the outward flow direction and away from the impingement area of the cross stream jets  342   a - 342   n  with the immediate thrombotic deposit or lesion  144  and/or the wall of the blood vessel  142 , thus distancing the highly concentrated cross stream jets  342   a - 342   n  from the immediate thrombotic deposit or lesion  144  and/or the wall of the blood vessel  142 , and thereby minimizing potential blood vessel wall damage. Such distancing also removes the inflow orifice  316  from close proximity with and away from the opposed wall of the blood vessel  142 , thereby minimizing the chance of ingestion of the blood vessel  142  wall structure by the inflow orifice  316 . 
     The cross stream jets  342   a - 342   n  traversing between the outflow orifice  314  and the inflow orifice  316  combine to offer an enhanced broad cross section ablation area, such area having a breadth substantially larger and having more concentrated force than prior art devices using multiple inflow and outflow orifices where cross streams are of diminished force and breadth. Having a concentrated flow combining cross stream jets  342   a - 342   n  offers selective and directed ablation to take place. Prior art devices using multiple inflow and outflow orifices and having multiple flow areas generate cross streams which are equally weak in all directions, as the flow force is divided between the multiple flow streams, whereby ablation forces cannot be concentrated where desired. The distal end of the smooth catheter tube  324  can be rotated axially to direct the cross stream jets  342   a - 342   n  about a longitudinal axis to have 360.degree. coverage or can be rotated axially to offer coverage partially about the longitudinal axis or can be operated to and fro, as required. 
       FIG. 27 , a third alternative embodiment, is an isometric view of an enhanced cross stream mechanical thrombectomy catheter with backloading manifold  410  incorporating much of the structure previously described, but differing by the substitution of a smooth catheter tube assembly  412 , including a smooth catheter tube  424 , which is curved approximately 180.degree, and other components and structure housed in the smooth catheter tube assembly  412  for the straight smooth catheter tube assembly  19  and previously described components and structure housed in the straight smooth catheter tube assembly  19  of the first embodiment. Also, previously described components are utilized including the components of or components attached to or associated with the centrally located backloading manifold  12  involving the hemostatic nut  14 , the introducer  15 , the flexible and tapered strain relief  16 , and the braided catheter tube  18 . The smooth catheter tube  424 , which is continuous, flexible and exhibits position memory, includes a curved section  424   a  located between a reversed section  424   b  and a straight section  424   c  opposing the reversed section  424   b . The smooth catheter tube assembly  412  is connected to and extends distally from the braided catheter tube  18  at a junction  118   c  and includes an outflow orifice  414  and an inflow orifice  416  each extending through the wall of the reversed section  424   b  of the smooth catheter tube  424  and each located in longitudinal alignment along an imaginary line at the inwardly facing aspect  418  of the reversed section  424   b  of the smooth catheter tube  424  and each opposingly facing the straight section  424   c  of the smooth catheter tube  424 . Also included as part of the reversed section  424   b  is a distally located flexible tapered tip  420 . Radiopaque marker bands  419  and  421  are located on the reversed section  424   b  of the smooth catheter tube  424  flanking the outflow orifice  414  and the inflow orifice  416 . 
       FIG. 28  is a partially exploded isometric view of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  410 ; and  FIG. 29  is a cross section side view of the components of the distal region of the smooth catheter tube assembly  412  along line  29 - 29  of  FIG. 27 . With reference to  FIGS. 28 and 29 , the third alternative embodiment is now further described. 
     The smooth catheter tube assembly  412 , the components of which are depicted fully in  FIGS. 27 and 28 , includes a lumen  422  extending the length of the centrally located smooth catheter tube  424  including the flexible tapered tip  420 , the reversed section  424   b , the curved section  424   a , and the straight section  424   c  about which and in which other components are located to connect with the lumen  110  of the braided catheter tube  18  at or near the junction  118   c  to the interior of the backloading manifold  12 . The proximal portion of the high pressure tube  71  extends distally and through the lumen  110  of the braided catheter tube  18 , and thence along the lumen  422  of and along the smooth catheter tube  424  to terminate as part of the fluid jet emanator  116 , shown in  FIG. 29 , adjacent to the flexible tapered tip  420  at the distal end of the lumen  422  of the smooth catheter tube  424 . In addition to the inwardly facing aspect  418  along the reversed section  424   b , outwardly facing aspects are incorporated into the smooth catheter tube  424 , including an outwardly facing aspect  426  along the outer portion of the reversed section  424   b  and an outwardly facing aspect  428  along the outer portion of the straight section  424   c . Also shown in  FIG. 27  is the junction  118   c  between the smooth catheter tube assembly  412  and the braided catheter tube  18 , such junction being suitably effected to provide for a smooth and continuous coupling of the smooth catheter tube assembly  412  and the braided catheter tube  18 . 
     Mode of Operation 
     The mode of operation of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  410  is explained with reference to  FIGS. 29, 30 and 31 . High velocity fluid jets  440   a - 440   n  are shown emanating proximally from the plurality of jet orifices  122   a - 122   n  of the terminated loop  117  into the lumen  422  of the smooth catheter tube  424  for subsequent creation of and culminating in cross stream jets  442   a - 442   n , shown by heavy lines, where the high velocity fluid jets  440   a - 440   n  flow as cross stream jets  442   a - 442   n  from the outflow orifice  414  and return through the inflow orifice  416 , while accomplishing ablative action with adhered blood vessel thrombus material and for maceration of foreign material in concert with the high velocity fluid jets  440   a - 440   n . Foreign material is introduced through the inflow orifice  416  and into the lumen  422  after dislodging from a vessel wall for macerating impingement by the high velocity fluid jets  440   a - 440   n . Macerated foreign material, i.e., thrombotic particulate, contained in the cross stream jets  442   a - 442   n , flows through and within the lumen  422  of the smooth catheter tube  424 , as also depicted by heavy lines. The cross stream jets  442   a - 442   n , while being forcefully directed outwardly and toward the wall of the blood vessel  142  by opposite reaction, urge the distal portion of the smooth catheter tube  424  in the direction opposite the outward flow direction and away from the impingement area of the cross stream jets  442   a - 442   n  with the immediate thrombotic deposit or lesion  144  and/or the wall of the blood vessel  142 , thus distancing the cross stream jets  442   a - 442   n  from the immediate thrombotic deposit or lesion  144  and/or the wall of the blood vessel  142 , and thereby minimizing potential blood vessel wall damage. More specifically, the reversed section  424   b  can be positioned in very close proximity with or can intimately engage the inner wall of the blood vessel  142 , as described later in detail. Such distancing also removes the inflow orifice  416  from close proximity with and away from the opposed wall of the blood vessel  142 , thereby minimizing the chance of ingestion of the blood vessel  142  wall structure by the inflow orifice  416 . The cross stream jets  442   a - 442   n  traversing between the outflow orifice  414  and the inflow orifice  416  combine to offer an enhanced broad cross section ablation area, such area having a breadth substantially larger and having more concentrated force than prior art devices using multiple inflow and outflow orifices where cross streams are of diminished force and breadth. Having a concentrated flow combining cross stream jets  442   a - 442   n  allows selective ablation to take place. 
       FIG. 30  is a side view of the distal region of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  410  showing, in particular, the distal end of the smooth catheter tube  424  positioned in a blood vessel  142  (shown in cross section) at a site of a thrombotic deposit or lesion  144 , and  FIG. 31  is a cross section view along line  31 - 31  of  FIG. 30  showing ablative action of the cross stream jets  442   a - 442   n  with the thrombotic deposit or lesion  144 , as previously described, and additionally shows abrading or scraping action of the distal end of the smooth catheter tube  424  by intimate contact with foreign matter, such as thrombus material  144 , in a blood vessel  142  which could be a large blood vessel. While  FIG. 30  depicts the smooth catheter tube  424  as being in a blood vessel in particular, it is to be understood that it is not limited to use in a blood vessel, but has utility with respect to any body cavity in general. High velocity fluid jets  440   a - 440   n  (shown in  FIG. 29 ) of saline or other suitable solution are emanated or emitted in a proximal direction from the fluid jet emanator  116  into the smooth catheter tube  424  and pass through the outflow orifice  414  creating cross stream jets  442   a - 442   n  directed toward the wall of the blood vessel  142  having thrombotic deposits or lesions  144 , and thence are influenced by the low pressure at the inflow orifice  416  to cause the cross stream jets  442   a - 442   n  to be directed distally substantially parallel to the central axis of the blood vessel  142  to impinge and break up thrombotic deposits or lesions  144  and to, by entrainment, urge and carry along the dislodged and ablated thrombotic particulate  146  of the thrombotic deposits or lesions  144  through the inflow orifice  416 , a relatively low pressure region, and into the lumen  422  which functions as a recycling maceration lumen or chamber. The entrainment through the inflow orifice  416  is facilitated by a low pressure source presented by the high velocity fluid jets  440   a - 440   n . The outflow is driven by internal pressure which is created by the high velocity fluid jets  440   a - 440   n . The enhanced clot removal is enabled because of the recirculation pattern established between inflow and outflow orifices  416  and  414 , which creates a flow field that maximizes drag force on wall-adhered thrombus and because of impingement of the cross stream jets  442   a - 442   n.    
     Intimate contact of or close proximity of the generally distal portion of the smooth catheter tube  424  to the inside wall of the blood vessel  142 , as shown best in  FIG. 31 , offers yet another innovative method of thrombotic deposit or lesion  144  removal. The cross stream jets  442   a - 442   n , while being forcefully directed outwardly and toward the wall of the blood vessel  142  during ablation activities by opposite reaction, urge the generally distal portion of the smooth catheter tube  424  in the direction opposite the outward flow direction and away from the impingement area of the cross stream jets  442   a - 442   n  with the immediate thrombotic deposit or lesion  144  and/or the wall of the blood vessel  142 , thus distancing the cross stream jets  442   a - 442   n  from the immediate thrombotic deposit or lesion  144  and/or the wall of the blood vessel  142 , and thereby minimizing the danger or chance of potential blood vessel wall damage or ingestion. Thus, the reversed section  424   b , particularly the outwardly facing aspect  426  thereof, is forcibly maneuvered into intimate contact or into close proximity to the inside wall of the blood vessel  142 , as shown in  FIG. 31 . Such intimate contact or close proximity to the inside wall of the blood vessel  142  is utilized to advantage by rotating the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  410 , particularly the smooth catheter tube  424 , within the blood vessel  142 , such as indicated by rotation arrows  444 . Such causes scraping and abrading impingement of the reversed section  424   b , especially the outwardly facing aspect  426  thereof, with the thrombotic deposit or lesion  144  at or near the inner wall of the blood vessel  142  to urge thrombotic (and lesion) particulate  146   a  to part from the general structure of the thrombotic deposits or lesion  144  and be entrained into the flow of the cross stream jets  442   a - 442   n  for maceration and/or evacuation through the lumen  422 , as shown in  FIG. 31 . To and fro operation of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  410  can also be incorporated into operation of the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  410  either singularly or in combination with rotation, as just described. Further, if the general distal end of the smooth catheter tube  424  is larger, or if the blood vessel is smaller, both the straight section  424   c  with the outwardly facing aspect  428  and the reversed section  424   b  with the outwardly facing aspect  426  can be utilized for rotational or for to and fro motion scraping and abrading impingement with the thrombotic deposits or lesions  144  at or near the inner wall of the blood vessel  142  to urge thrombotic (and lesion) particulate  146   a  to part from the general structure of the thrombotic deposits or lesion  144  to be entrained into the flow of the cross stream jets  442   a - 442   n  for maceration and/or evacuation through the lumen  422 . Even more vigorous scraping and abrading could be accomplished if the general distal end of the smooth catheter tube  424  were slightly oversized with respect to the blood vessel  142 . 
     A previously placed guidewire (not shown) is incorporated to load the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  410  within the vasculature by first utilizing the distal end of the lumen  422  followed by subsequent advancement by the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  410  along the guidewire in close proximity to a thrombus site. In the alternative, the first guidewire can be withdrawn completely from the enhanced cross stream mechanical thrombectomy catheter with backloading manifold  410  and swapped by backloading with another guidewire of other properties and attributes, if required. An advantage of an embodiments of the present disclosure is that the guidewire can be introduced by a front loading approach or by a backloading approach and, therefore, can be removed and reintroduced or can be replaced by a different guidewire. 
     The concentrated cross stream jets  442   a - 442   n  traversing between the outflow orifice  414  and the inflow orifice  416  combine to offer an enhanced broad cross section ablation area, such area having a breadth substantially larger and having more concentrated force than prior art devices using multiple inflow and outflow orifices where cross streams are of diminished force and breadth. Having a concentrated flow combining cross stream jets  442   a - 442   n  offers selective and directed ablation to take place. Prior art devices using multiple inflow and outflow orifices and having multiple flow areas generate cross streams which are equally weak in all directions, as the flow force is divided between the multiple flow streams, whereby ablation forces cannot be concentrated where desired. The distal end of the smooth catheter tube  424  can be rotated axially to direct the cross stream jets  442   a - 442   n  about a longitudinal axis to have 360.degree. coverage or can be rotated axially to offer coverage partially about the longitudinal axis, as required. 
       FIG. 32 , a fourth alternative embodiment, is a side view of a smooth catheter tube  450  similar for the most part to and using components associated with the smooth catheter tube  20  of the first embodiment for use with an enhanced cross stream mechanical thrombectomy catheter with backloading manifold. The smooth catheter tube  450  includes a flexible tapered tip  452 , an inflow orifice  458 , and an outflow orifice  460 , each orifice extending through the wall of the smooth catheter tube  450  where the outflow orifice takes on an L-shape to influence and shape the pattern of the cross stream jets which pass therethrough. The outflow orifice  460 , as well as even the inflow orifice, could incorporate other shapes, such as, but not limited to, round, oval, elliptical, obround, tapered, slotted, rectangular, and rounded corner, or could be protruding. Radiopaque marker bands  454  and  456  are provided, as in the other embodiments. 
       FIG. 33 , a fifth alternative embodiment, is a view of the distal portion of an alternatively provided smooth catheter tube assembly  19   a  incorporating the components of the smooth catheter assembly  19  shown in the first embodiment including additional outflow orifices and inflow orifices in equal and symmetric angular off-center opposition to the main outflow orifice  22  and the main inflow orifice  24 . 
       FIGS. 34 a  and 34 b    are cross section views through the outflow orifices and inflow orifices of the smooth catheter tube assembly  19   a  along the lines  34   a - 34   a  and  34   b - 34   b  of  FIG. 33 . With reference to  FIGS. 33, 34   a  and  34   b , the additional outflow and inflow orifices are now described. The additional outflow orifices  500  and  504  and inflow orifices  502  and  506 , in sets, are located along imaginary lines extending longitudinally along the distal surface of the smooth catheter tube  20  and extend through the wall of the smooth catheter tube  20  where such imaginary lines preferably are parallel and offset in equiangular and symmetrical fashion from direct opposition with an imaginary line upon which the outflow orifice  22  and the inflow orifice  24  can align. Although two sets of additional outflow orifices and inflow orifices are shown, any number of sets can be incorporated as desired so long as symmetry is maintained. The sets of additional outflow orifices and inflow orifices include outflow orifices  500  and  504  and inflow orifices  502  and  506  which are smaller than outflow orifice  22  and inflow orifice  24  which, in total and in combination, produce additional cross stream jet flow, force and quantity less than that provided by the outflow orifice  22  and the inflow orifice  24 . One additional set of outflow orifices and inflow orifices includes an outflow orifice  500  and an inflow orifice  502 . Another additional set of outflow orifices and inflow orifices includes an outflow orifice  504  and an inflow orifice  506 . 
       FIG. 35  is a side view in cross section like  FIG. 10  wherein the distal portion of the smooth catheter tube  20  additionally shows the outflow orifice  504  and the inflow orifice  506  in the structure thereof. In addition to the attributes, features and flow paths described in  FIG. 10 , high velocity fluid jets  136   a - 136   n  are shown emanating proximally from the plurality of jet orifices  122   a - 122   n  into the lumen  112  of the smooth catheter tube  20  for subsequent creation of and culminating in cross stream jets  508   a - 508   n  shown traveling from the outflow orifice  504  and returning through the inflow orifice  506  for entry for maceration by the high velocity fluid jets  136   a - 136   n  and/or exhausting proximally with the flow within the distal portion of the smooth catheter tube  20  as generally depicted by arrowed lines. The outflow orifice  500  and the inflow orifice  502  are incorporated into use in the same manner culminating in symmetrically disposed cross stream jets  510   a - 510   n  traveling from the outflow orifice  500  and returning through the inflow orifice  502 , as shown in  FIG. 36 . 
     In addition to longitudinal alignment of the outflow orifice  500  and corresponding inflow orifice  502  and of the outflow orifice  504  and corresponding inflow orifice  506  with respect to each other and to the inflow orifice  22  and the outflow orifice  24  along imaginary lines, symmetrical alignment attributes and relationships are also addressed in the terms of cross stream jet flow region relationships as shown in  FIGS. 34 a  and 34 b   . A major cross stream jet flow region  512  centers along and about the cross stream jets  140   a - 140   n , the outflow orifice  22  and the inflow orifice  24  and substantially along the center of the lumen  112 , such region being substantially perpendicular to the outflow orifice  22  and the inflow orifice  24 . In a somewhat similar fashion, a minor cross stream jet flow region  514  centers along and about the cross stream jets  510   a - 510   n  ( FIG. 36 ), the outflow orifice  500  and the inflow orifice  502  and substantially along the center of the lumen  112  such region being substantially perpendicular to the outflow orifice  500  and the inflow orifice  502 . Also in a somewhat similar fashion, a minor cross stream jet flow region  516  centers along and about the cross stream jets  508   a - 508   n , the outflow orifice  504  and the inflow orifice  506  and substantially along the center of the lumen  112 , such region being substantially perpendicular to the outflow orifice  504  and the inflow orifice  506 . Symmetrical angular relationships are maintained between major cross stream jet flow region  512  and each of the minor cross stream jet flow regions  514  and  516 . For purposes of example and illustration, an angle X between the major cross stream jet flow region  512  and the minor cross stream jet flow region  514  corresponds to and is the same value as an angle X between the major cross stream jet flow region  512  and the minor cross stream jet flow region  516 , whereby symmetry exists. The value of the angle X can be unilaterally changed during manufacturing to maintain symmetry, as just previously described. The resultant combination of symmetric but lesser flow along and about the minor cross stream jet flow regions  514  and  516  opposes the stronger flow along and about the major cross stream jet flow region  512  to assist in centering of the smooth catheter tube assembly  19   a  within a blood vessel, as well as offering ablation services while still allowing urging of the smooth catheter tube assembly  19   a  toward the periphery of a blood vessel  142 . 
       FIG. 36  is like  FIG. 11  wherein a side view of the distal region of the enhanced cross stream thrombectomy catheter with backloading manifold  10  incorporating the use of the smooth catheter tube assembly  19   a  is shown positioned in a blood vessel  142  at a site of a thrombotic deposit or lesion  144  or other undesirable matter. In addition to and in cooperation with the mode of operation of the first embodiment, such as described with reference to  FIG. 11  and associated figures, the use and features of the outflow orifice  500  and the inflow orifice  502  and of the similarly constructed and similarly functioning outflow orifice  504  and inflow orifice  506  (not shown in this  FIG. 36 ) are described. The cross stream jets  510   a - 510   n , which are directly related to the minor cross stream jet flow region  514  and similar to cross stream jets  508   a - 508   n  which are directly related to the minor cross stream jet flow region  516 , are directed away from the main cross stream path such as provided by the cross stream jets  140   a - 140   n  which are directly related to the major cross stream jet flow region  512 , to offer additional ablation and exhausting of thrombotic deposits or lesions  144  to that region where the smooth catheter tube  20  is directed and urged toward the blood vessel  144  by the more influential power of the relatively stronger cross stream jets  140   a - 140   n . Such positional urging of the smooth catheter tube  20 , as described in the first embodiment, is the dominant factor in urging of the smooth catheter tube  20  away from the wall of the blood vessel  142  near the outflow orifice  22  and the inflow orifice  24 , as the flow and force therethrough is greater than that provided by such combined flow and force through the outflow orifice  500  to the inflow orifice  502  and through the outflow orifice  504  to the inflow orifice  506 . The use of the outflow orifice  500  and the inflow orifice  502  and of the similarly constructed and similarly functioning outflow orifice  504  and the inflow orifice  506  provides for more complete ablation and exhausting while still allowing urging of the smooth catheter tube  20  towards the side of the blood vessel  142  opposite the greater ablation activity. Symmetry of the cross stream jet flows is provided by the equiangular offset of the outflow orifice  500  and the inflow orifice  502  and of the similarly constructed and similarly functioning outflow orifice  504  and the inflow orifice  506  with respect to the cross stream jet flow provided by the outflow orifice  22  and the inflow orifice  24 . Such symmetry ensures stability of the smooth catheter tube assembly  19   a  during ablation procedures. 
     Various modifications can be made to the present disclosure without departing from the apparent scope thereof.