Multi-barrel syringe injection system

An injection device for injecting a medicant into a plurality of tissue sites in a patient for a selected treatment is constructed and arranged such that the number of tissue sites is the total number for the selected treatment thereby requiring a single positioning step. The injection device includes a body having a syringe and a control linkage, the syringe including a plurality of barrels, and a cooperating plunger array including a plurality of plungers. Each barrel receives a corresponding plunger. The injection device further includes a plurality of injection needles connected to the syringe wherein one injection needle is connected to each barrel, a multi-lumen tip, a shaft connected to the multi-lumen tip and extending between said multi-lumen tip and said body. The control linkage is connected to each needle so as to move each needle between a deployed injection position and a retracted position.

BACKGROUND

Injection needle devices and systems are used to inject a medicant into a tissue site of a patient. One current style of injection needle device uses a plurality of needles, for example three (3). When the desired number of injection sites into the tissue is greater than the number of needles provided as part of the injection needle device, multiple injection cycles must be performed. In order to perform a second injection cycle with the device, it is necessary to turn, rotate or reposition the device so that the needles of the device are aligned with additional tissue sites which are intended to receive an injection of the medicant. This repositioning requires that the extended or deployed needles first be retracted or withdrawn so as not to extend from the tip of the device and then, depending on the tissue site, the tip of the device may have to be partially retracted in order to be turned and repositioned before the needles are once again deployed (i.e. extended from the tip) for injection of the medicant into other tissue sites.

The tip of the injection device which is intended to be positioned adjacent the tissue site, includes an array of apertures which receive the injection needles. A mechanical deployment structure is used to extend the pointed and open tips of the needles (one (1) needle per aperture) for the injection of medicant and in order to retract the tips of the needles when the device is not in use and/or when the device is being repositioned for a second or subsequent injection cycle.

In one example of an earlier injection device, there are three (3) injection needles and the selected injection procedure includes nine (9) desired tissue injection sites. A specific use of this earlier device would be for the injection of autologous derived cells into the urinary sphincter of a patient for the treatment of stress urinary incontinence (SUI). In order to deliver medicant to each of the nine (9) tissue injection sites, three (3) injection cycles must be performed. A degree of precision in the positioning and orientation of the device is required and the desired degree of precision is difficult to exercise. The tip of the device is held at the meatus of the sphincter while extending (i.e. deploying) the three (3) injection needles into the tissue. A delivery syringe in cooperation with a common manifold is used for delivering medicant from that common manifold to each of the three (3) injection needles. Assuming that the common manifold initially contains all of the medicant for the nine (9) tissue sites, it becomes important that manipulation of the delivery syringe be used in such a way that its plunger is only depressed approximately one-third (⅓) of its total travel in order to deliver the desired or correct dosage (approximately one-third) of cell-based treatment (i.e. the medicant) as part of the first injection cycle. This constitutes the first cycle of three (3) and is completed when the three (3) needles are withdrawn into the tip of the device so that the device can be repositioned for the second injection cycle to be performed. Part of the repositioning of the device for the second cycle requires that the device be rotated so as to reposition the three (3) needles, actually the three (3) needle apertures since the needle tips have been retracted, to the desired location of three (3) new tissue sites for the next three (3) injections into those sites. At this second position for the second injection cycle, the three (3) needles of the device are extended or deployed into the tissue and the common syringe plunger is depressed another one-third (⅓) of its travel into the common manifold. This is intended to deliver the second one-third (⅓) of the medicant at these three (3) new tissue sites. Six (6) of the nine (9) selected injection sites have now received an injection of the medicant, presumably the scheduled dosage of the medicant. The third and final cycle is essentially a repeat of the second cycle. This third cycle begins when the device is rotated to the position where the three (3) needle apertures are aligned with the final three (3) injection sites. The needles are then deployed for medicant injections into the final three (3) tissue sites.

One of the concerns with the type of injection device which has been described is that it uses a separate syringe which is suspended from a luer connection at its proximal end. This assembly approach presents a concern regarding the structural integrity of the connection. A further concern with this type of earlier injection device, as described, is the use of a manifold to flow couple the three (3) needles to be syringe. The use of a manifold in this context may introduce turbulence and an inconsistent distribution of the medicant. Another concern is the use of a separate syringe and the inability to purge air from the system. Further, with the need for and use of long needle cannulas, the volume of the cannulas becomes a concern.

The type of injection device which has been described as being representative of some earlier constructions, includes a manifold or reservoir for the medicant and the manifold is either directly or indirectly connected to each of the three (3) needles which are arranged in parallel. A single plunger is cooperatively arranged with the manifold for pushing the medicant into and through each needle. If one tissue site is more dense than another tissue site, the amount of medicant which is injected at each site will not be equal. If individual syringe barrels are associated with each needle and if each barrel has its own cooperating plunger and piston, then this inequality problem in medicant distribution among the selected tissue sites would be solved. This is the selected structure which is disclosed herein in the exemplary embodiment.

The various design issues and concerns which are outlined above are the focus of the embodiments of the present disclosure. The preferred embodiment incorporates a multi-barrel syringe and a needle count which corresponds to the number of desired tissue injection sites for the particular treatment. Cooperating elements and structures of the multi-barrel syringe provide other design features which are considered to be novel and unobvious relative to the current state of the art.

SUMMARY

In at least one embodiment of the present disclosure, a multi-barrel syringe is provided, as part of an injection system, for injecting a medicant into a plurality of tissue injection sites in a patient.

An injection device for injecting a medicant into a plurality of tissue sites in a patient for a selected treatment is disclosed wherein the number of tissue sites is the total number for the selected treatment thereby requiring a single positioning step. The injection device includes a body having a syringe and a control linkage, the syringe including a plurality of barrels, and a cooperating plunger array including a plurality of plungers, wherein each barrel receives a corresponding plunger. The injection device further includes a plurality of injection needles connected to the syringe wherein one injection needle is connected to each barrel, a multi-lumen tip, a shaft connected to the multi-lumen tip and extending between the multi-lumen tip and the body, the shaft receiving a portion of each injection needle. Wherein the control linkage is connected to each needle and is constructed and arranged to move each needle relative to the multi-lumen tip between a deployed injection position and a retracted position, wherein the number of needles is at least as great as the number of tissue sites for the selected treatment.

An injection system for injecting a medicant into a plurality of tissue sites in a patient for a selected treatment is disclosed wherein the number of tissue sites is the total number for the selected treatment thereby requiring a single positioning step. The injection system includes a filling syringe, a charge of medicant loaded into the filling syringe, and an injection device. The injection device includes a body having a plurality of barrels, a plurality of injection needles, wherein each needle is connected to a corresponding barrel, a multi-lumen tip for positioning an open tip of each injection needle at a corresponding one of the injection sites, means for connecting the multi-lumen tip with the body and means for moving each injection needle of between a deployed, injection position and a retracted position.

A method of preparing for use and using an injection device for injecting a medicant into a plurality of tissue sites in a patient for a selected treatment is disclosed. The method includes the steps of providing a filling syringe, providing a charge of medicant for delivery by the filling syringe, providing an injection device having a plurality of barrels, a plunger array, a plurality of injection needles with one needle connected to each barrel, an injection tip which receives an open tip of each injection needle and means for moving each injection needle to a deployed injection position, inserting the filling syringe into the injection device, filling each syringe with medicant, moving the plunger array to purge air from within the plurality of injection needles, retracting the open tip portion of each needle, positioning the injection tip at the tissue sites, moving each injection needle to a deployed injection position into its corresponding tissue site and moving the plunger array to inject medicant into each tissue site.

DESCRIPTION OF THE SELECTED EMBODIMENTS

Referring toFIGS. 1-6Athere is illustrated a multi-barrel syringe injection device20which constitutes the primary structural member of a multi-barrel syringe injection system. The use of “system” is intended to include, in addition to device20, the medicant and the medicant-delivery syringe or similar device which connects to device20for introducing the initial charge of medicant into device20and for refilling or recharging of device20with additional medicant, if or as required. The manner of connection and the arrangement for the delivery of medicant is diagrammatically illustrated inFIG. 7. As is shown, delivery syringe22contains a volume of medicant24. The tip26of syringe22is inserted into L-shaped adapter28with a luer connection. Depressing plunger30(in the direction of the arrow) delivers an initial charge of medicant24into device20. With reference toFIGS. 8 and 8A, adapter28defines a continuous flow passageway28atherethrough for the injected medicant from syringe20to flow through adapter28and then through manifold hub29(seeFIGS. 14, 14A, 14B and 14C) into the medicant chamber36of each barrel35, as will described in additional detail later in this disclosure. The externally-threaded, hollow post27of adapter28securely threads into the internally-threaded hole31of manifold hub29. The specific storage and handling of this initial charge of medicant24by device20begins by injecting the medicant through adapter28and into the inlet end31of manifold hub29. There are nine (9) passages32(seeFIG. 14C) which connect the inlet end31to a corresponding barrel aperture33. In the exemplary embodiment these nine (9) passages32are equally spaced for a more efficient utilization of the available space. The manifold configuration divides the single incoming flow of medicant into nine (9) branches. Each barrel aperture33establishes a luer connection with the filling tip34(and filling passage34a) of each barrel35, seeFIGS. 16, 16A and 16B. The tapered fitting between aperture33and filling tip34is smaller than the “standard” luer, but uses essentially the same taper angle as the standard luer. Additional details of hub29and barrel35will be described later in this disclosure.

Upper end28bof L-shaped adapter28extends beyond the body of device20as shown by the small protruding portion. Adapter28remains threadedly connected to manifold hub29after a charge of medicant24has been delivered to each medicant chamber36. In order to keep debris out of upper end28band accordingly out of passageway28a, a small cap (or plug), not illustrated, with a cooperative luer connection is connected into upper end28bwhen the delivery syringe22is disconnected and removed after delivery of the medicant24.

A “luer connection”, as that phrase is used herein, refers to the use of a luer taper as part of a standardized system of small-scale fluid fittings used for making a leak-free connection between a male taper fitting and its mating femal part. There are two varieties which are generally referred to as “Luer-Lok®” and “Luer-Slip®”. The first includes threads while the other relies on friction.

This disclosure includes several references to the connection, joining or attachment of one component part to another, or to others. When the connection, joining or attachment is intended to be secure (and/or establish a tight seal), one of several fabrication or assembly techniques or methods may be suitable, depending primarily on the material selections for the component parts and secondarily on the shape and size of the component parts. One connection, joining or attachment approach is to use an adhesive so as to bond one component part to the other(s). Preferably, the selected adhesive is a medical grade adhesive and the approach or technique may include the use of UV light to initiate cross-linking. Another approach, primarily with plastics, is to use ultrasonic welding for fusing together the two component parts. When some other connection, joining or attachment approach is selected or preferred, and is beyond the scope of the options outlined above, that approach is described herein such as the use of an interference fit or the use of threaded fasteners. All fasteners and metal hardware used in the exemplary embodiment are made from a bio-compatible, stainless steel alloy.

As the plunger30is depressed, the medicant flows first in a single stream into the manifold hub29and then divides into nine (9) similar flow paths for filling the medicant chamber36of each barrel35, seeFIGS. 16, 16A and 16B. The distal end of chamber36is open at tip37and the opposite, proximal end38is open but will be closed off by the insertion of one (1) of nine (9) individual plungers39aof the nine (9) plunger array39(seeFIGS. 20 and 20A). The tip of each plunger39areceives an elastomeric seal or sealing piston168. Each one (1) of the nine (9) injection needles44is securely connected with the injection tip37of a corresponding one (1) of the nine (9) barrels35. The proximal end of each needle is media-blasted in order to roughen its outer surface. This proximal end of each needle44is then inserted into a corresponding injection tip37and the injection tip37and needle44are bonded together with a medical-grade adhesive which uses UV light to initiate cross-linking resulting in a secure and leak-free connection. The needles44extend through multi-lumen shaft40and then into tip42.

As each medicant chamber36is filled, the medicant24is able to flow out through its corresponding injection needle44. This flow logically only occurs when the chamber is filled as the path of least resistance for the excess medicant24is through the corresponding injection needle44. With the pointed end (i.e. the open tip44a) of each of the nine (9) needles44extended beyond the multi-lumen tip42, having full barrels35and full needles44is shown by the excess flow of medicant droplets coming out of the open tip44aof one (1) or more of the needles44. The direction of the falling droplets (seeFIG. 7) is representative of pointing device20and corresponding tip42in an upward direction to ensure full filling of each barrel35before droplets appear.

The next initial preparation step before positioning multi-lumen tip42at the treatment site within the patient is to move lever41forward (seeFIGS. 19 and 19A). This lever movement results in forward movement of the nine (9) plunger array39. As will be described in greater detail later in this disclosure, the plunger39acorresponding to each barrel35moves forward and closes off the reverse flow path back into delivery syringe22via filling tip34and filling passage34a. Slight further advancing of the array39purges any excess air which may be found in the nine (9) medicant flow paths from chamber36to the open tip44aof the corresponding needle44. An essentially complete purge of air is shown, again, by the discharge of medicant droplets from the open tips44aof the needles44. The plungers need to then be advanced to a known position (detent or marked increments) corresponding to the correct dosage for the treatment. At the very least the plunger position needs to be noted so that a known dosage is injected. A clear housing or window over the syringe barrels are other options. The needle tips44aare then withdrawn (i.e. retracted) into multi-lumen tip42and device20is now ready for use. The remaining steps are to position the tip42at the treatment site, deploy or advance the tip of each needle so as to extend those pointed, open tips44ainto the corresponding tissue sites. With each needle tip inserted into the corresponding tissue site, the lever41is again used to move plunger array39forward so as to dispense at least a portion of the medicant in each chamber36into the tissue at the corresponding tissue site. Preferably the entirety of each chamber36is emptied.

The exemplary embodiment of device20is directed at use in conjunction with the treatment of stress urinary incontinence (SUI). The treatment procedure preferably includes nine (9) tissue sites for injection of the selected medicant. For this exemplary treatment, nine (9) injection needles are used and accordingly there are nine (9) barrels35and plunger array39includes nine (9) individual plungers39aall part of an integral unit. The nine (9) barrels35are ganged together into an array subassembly. Design logic and uniformity suggests that the nine (9) barrels be arranged in an equally-spaced, cylindrical array similar to the cylinder of a pistol. This is illustrated inFIGS. 1-3and in the design of plunger array39, the assembly of the barrels35and the design of the manifold hub29.

When the tip42of device20is positioned at the meatus of the urinary sphincter, there is a further consideration and this is why the “12 o'clock” position does not have a corresponding needle44. This further consideration is due to the location of sensitive nerves which are to be avoided by the needles.

As should be understood, if device20or some variation of device20is to be used for some other treatment and/or for some other sphincter, for example, then the number of needles might change. It is also envisioned that the size of device20might change as the number of required needles increases or decreases. The arrangement, spacing and pattern of the needles at tip42may also change depending on the tissue sites and the desired treatment. All of these variables and variations are contemplated within the scope of the present disclosure.

It is important to note that theFIG. 7illustration of device20includes a two-part housing or cover. This enclosing housing, seeFIGS. 22 and 22A, includes a right-side body43and a left-side body43dwhich is essentially a mirror image of the right-side body43. The two (2) body halves create a clam-shell enclosing housing which at least partially encloses the trigger mechanism, the plunger array, the barrels and some of the related components. SeeFIGS. 1A, 2A, 3A, 4A, 5A and 6A. The hub86(seeFIG. 13) generally denotes the physical interface of the distal end of housing, including right-side body43and left-side body43d, and the multi-lumen shaft40. The two (2) body halves43and43dof the enclosing housing are fastened together using suitable fasteners which are known in the art and are arranged so as to extend through a plurality of structural portions, such as bosses43aas shown in the exemplary embodiment. Bosses43aare arranged so as to avoid internal features while enhancing the structural integrity of the assembly. The generally cylindrical posts43band43care used as pivot posts for the trigger98and for the lever39, respectively.

In order to be able to illustrate the internal construction and complexities of device20, the right-side body43of the housing is the only half included inFIGS. 1, 2, 3, 4, 5 and 6. The elected form of illustration for body43is in partial form, as a fully transparent component so as not to block or interfere with the illustrations of the other component parts. The full structure of body43is shown inFIGS. 22 and 22A. The fully assembled form of device20with both housing halves, i.e. body halves43and43d, is shown inFIGS. 1A, 2A, 3A, 4A, 5A and 6A.

With continued reference toFIGS. 1-6A, it is assumed that all of the component parts are properly configured and assembled, the housing halves which enclose the other component parts are properly shaped, assembled and fastened together. A charge of medicant24has been injected into device20, each barrel35is filled with medicant and any residual air in any of the needles44has been purged. The delivery syringe22has been removed and the small closing cap (or plug) has been connected. AlthoughFIGS. 1-6Aillustrate device20with the tips44aof the needles44extending out of tip42, the starting form of device20for placement within the patient is with the tips of the needles withdrawn or retracted into tip42. In this form, the tip42is able to be positioned at the desired treatment site without the needles interfering with the desired movement and positioning of device20.

One advantage of device20is the ability to make all of the desired tissue site injections with a single positioning of tip42. This eliminates any need to turn or rotate tip42and/or reposition the tip in another orientation for a second and then a third injection cycle. In the exemplary embodiment of device20, the nine (9) injection needles44are suitable in number and spacing for injections at nine (9) tissue sites into the urinary sphincter of the patient. The reference to nine (9) tissue sites is considered preferred as the example selected for the exemplary embodiment. This is a number which corresponds to the number of injection needles44. Different treatments and/or different sphincter sites might require a greater number of needles or a fewer number of needles, but regardless, device20is able to be modified accordingly consistent with what is provided and what is contemplated by the disclosed embodiments and treatment method.

A single treatment cycle with device20means that each needle44makes its medicant injection into its corresponding tissue site at a essentially the same time. Each barrel35has its own charge of medicant24and its own cooperating plunger39aand sealing piston168. Further, due to the essentially identical construction of each of the nine (9) barrels35, the medicant chamber36of each barrel holds essentially an identical amount or volume of medicant. As such, each tissue site receives essentially the same amount of medicant regardless of variations in tissue density or other variables. Prior art devices which use a single plunger for a plurality of barrels, via a manifold structure, are unable to address variations in the tissue characteristics such that each site receives an equal amount of injected medicant. With prior art devices, if one (1) tissue site has a higher or greater density of tissue, then based on the principal of the path of least resistance, the other sites will receive an increased dosage of medicant while the site with the greater tissue density will receive less medicant. This problem is solved by the disclosed embodiment. The construction of device20also allows an efficient air purge through each needle44and eliminates some of the fluid turbulence issues with earlier constructions. As noted regarding some of the earlier constructions, when a single plunger is used to push manifold fluid into a plurality of connected conduits, such as a plurality of barrels which communicate with a single manifold, fluid turbulence can occur.

With continued reference toFIGS. 1-6A, device20includes a number of unique component parts which are cooperatively assembled into the illustrated configuration of device20. The component parts which comprise device20are illustrated and described in functional groups beginning with the distal portion. Due to the cooperative relationship between all components there is no rigid boundary line as far as where one portion ends and another begins. Instead, this disclosure selects a few of the components at a time in order to describe their function, structure and cooperative relationship to other components or device20.

The distal portion of device20includes multi-lumen shaft40which is assembled into a multi-lumen tip42. This combination of shaft40and tip42receives nine (9) curled injection needles44which are used as part of the exemplary embodiment of device20and are used for the corresponding treatment method. The multi-lumen shaft40is a longitudinal or elongated member which includes an outer, generally cylindrical sleeve portion with interior ribs shaped with a fluted configuration, as is illustrated. Shaft40is a single-piece, unitary component including the sleeve portion45and the nine (9) interior ribs46. Shaft40is preferably made out of a polymeric material, and preferably fabricated by an extrusion process. The nine recessed channels40aare defined by and between each rib46. Each channel40ais constructed and arranged to receive a portion of each needle44. With each needle44fitted into its corresponding channel40afor the full length of shaft40, a generally cylindrical rod47is inserted into the remaining hollow interior of shaft40, extending through at least a portion of the overall length of shaft40. Rod47helps to retain each needle44in its corresponding channel40aduring use of device20, without misalignment and/or buckling of any needle44. Rod47is preferably sized to extend from a distal location within tip42to a proximal location adjacent multi-lumen ring88. This “adjacent” location includes a proximal location wherein rod47extends into at least a portion of the axial length of ring88. The annular size of each channel40a, in lateral cross section, is large enough relative to the diameter size of its corresponding needle44to permit each needle to freely slide through its corresponding channel40aas part of the deployment of the tip44aof each needle out of tip42.

A second embodiment for the multi-lumen structure which is represented by shaft40is to use a ribbed rod48(seeFIG. 10). Whether using the generally cylindrical tube form of shaft40for carrying the nine (9) injection needles, or using a ribbed rod48for the nine (9) needles, it is to be noted that there is a supporting structure in either of these two (2) embodiments preferably extending from the main body of device20to within the location of tip42. Likewise, whether using shaft40or using rod48, the distal tip of that structure inserts into the open proximal end of tip42which is accessible and used for their secure connection. An end section view of the cooperating, generally concentric assembly of needles44into shaft40is illustrated inFIG. 11. InFIG. 11A, an end section view is provided of the nine (9) needles44as they are received by the alternative embodiment using rod48. Rod48is a single-piece, unitary component which is preferably fabricated by an extrusion process from a polymeric material. Rod48defines nine (9) ribs48aand in alternating sequence with each rib48ais a recessed channel50. Each channel50is constructed and arranged to receive a corresponding needle44. In order to help secure each needle44in its corresponding channel50, a thin sleeve51is slipped over the needle-loaded rod48, seeFIG. 11A. Sleeve51helps to retain each needle44in its corresponding channel50during use of device20in this second embodiment, without misalignment and/or buckling of any needle44. Sleeve51is preferably sized to extend from a distal location within tip42to a proximal location adjacent the distal face of multi-lumen ring88. The annular size of each channel50, in lateral cross section, is large enough relative to the diameter size of its corresponding needle44to permit each needle to free slide through its corresponding channel50as part of the deployment of the tip44aof each needle out of tip42.

Whichever embodiment is selected as part of device20, each of the nine (9) needles are able to move freely within the selected carrier, whether within shaft40or around rod48so as to be extendable (i.e. deployed) out of openings in tip42or retracted back into tip42. The ribbed or fluted designs for these two (2) support members, whether shaft40or rod48, define nine (9) needle-receiving channels40a(see shaft40) or in the alternative embodiment channels50for use with rod48.

Multi-lumen tip42(seeFIG. 12) is preferably a subassembly of two (2) cooperating members, including a distal tip portion54(seeFIG. 12A) and a proximal tip portion56(seeFIG. 12B). These two (2) portions54and56are securely joined together in order to form tip42. With continued reference toFIGS. 12, 12A and 12B, portion54includes a closed, dome-shaped head58, a generally-cylindrical body60and a frustoconical base62which defines a pattern of nine (9) generally semi-cylindrical grooves64. The nine (9) grooves64extend the full frustoconical length of base62and create break-out apertures66adjacent the lower edge68of body60.

With continued reference toFIGS. 12, 12A, 12B and 12C, portion56includes an open-tapered proximal end70and an opposite end72which is shaped with a recessed frustoconical surface74. Surface74defines nine (9) generally semi-cylindrical grooves76which are sized, shaped and arranged to cooperate with grooves64when the two portions54and56are securely joined together into tip42. Grooves76extend the full frustoconical length of surface74creating break-out edge apertures73and75which are generally semi-circular or part-oval in shape. Apertures73are adjacent outer edge77and apertures75are adjacent inner edge79. Inner edge79corresponds to surface81which is at the distal end of the counterbore82. Open end83receives the distal end of shaft40. Edge77is in tight abutment with edge68as portions54and56are securely joined together. This assembly results in two (2) sets of edge apertures (apertures66and73) combining to cooperatively define the nine (9) needle openings78which are shown as being defined by multi-lumen tip42, seeFIG. 12as an example.

Base62fits within the recess of opposite end72and abuts up against surface74such that grooves64and grooves76define nine (9) needle-receiving passages80. These passages80begin at the location of surface81. These passages end at the location of the defined needle openings78. When multi-lumen shaft40and multi-lumen tip42are properly assembled and joined together, the nine (9) defined needle channels40aare aligned with the nine (9) passages80which are in communication with the nine (9) needle openings78. In the alternative embodiment, involving the use of rod48, its defined needle channels50are aligned with the nine (9) passages80which are in communication with the nine (9) needle openings78.

The multi-lumen shaft40is sized and shaped to fit closely within counterbore82and is securely connected therewith. The cylindrical rod47has a sliding fit through the interior of shaft40and one way to fix rod47in position and one way to fix the relationship between rod47and sleeve40is to securely attach the end of rod47to the center portion of surface81. The connection of rod47to surface81still leaves open the proximal entrance to each passage for receipt of a corresponding needle.

With continued reference toFIGS. 1-6A, device20further includes a hub86, a multi-lumen shaft ring88and nine (9) barrels35. The construction of hub86is illustrated inFIG. 13. The construction of multi-lumen shaft ring88is illustrated inFIGS. 15 and 15A. The construction of each barrel35is illustrated inFIGS. 16, 16A and 16B.

Hub86is preferably a single-piece, unitary component which is injection molded from a polymeric material, such as polyacetal. Ring88is preferably a single-piece, unitary component which is injection molded from a polymeric material. Each barrel35is preferably a single-piece, unitary component which is injection molded from a polymeric material, such as polycarbonate or polypropylene.

As illustrated in the assembled configuration of device20, multi-lumen shaft40extends through at least a portion of hub86. As the proximal ends of the nine (9) needles exit from shaft40in the vicinity of hub86, those nine (9) needles are received by the nine (9) needle-receiving channels92which are defined by ring88. A portion of shaft40is securely attached to hub86by the use of a suitable adhesive. Preferably cylindrical rod47extends into and through ring88to help facilitate the initial positioning and retention of the needles44within the receiving channels92of ring88. The nine (9) barrels35are sized and shaped so as to generally fit together into a generally cylindrical array which is identified herein as the barrel subassembly94. The distal end of tip37of each barrel35receives one end of the corresponding curled injection needle44. The curled portion44bof each needle44is positioned in a clearance space95within the housing of device20. Clearance space95is positioned between the barrel subassembly94and ring88. The uncurled, straight portion of each needle44which extends from its curled portion44bto its open pointed tip44a, extends through a corresponding channel92and then through a corresponding channel40a. In tip42, each needle44extends through a corresponding passage80. When deployed, the tip of each needle protrudes out of its corresponding opening78as is illustrated inFIGS. 1 and 1A.

The portion of each needle44which is received by its corresponding channel92is securely attached within and to ring88using a suitable adhesive. As a result of this secure connection between needles44and ring88, movement of ring88causes movement of the nine needles44. Movement of the needles is required to be able to deploy and retract the needle tips44arelative to multi-lumen tip42.

The use of device20allows the needles44to be moved from a retracted position to an extended or deployed position as noted. In the retracted position the pointed tip44aof each needle44does not protrude out of its corresponding needle opening78in tip42. In the extended position the open pointed tip44aof each needle44is extended out through its corresponding opening78, into the corresponding and selected tissue site. The tissue sites are not shown inFIG. 1, but it is to be understood that with proper positioning of tip42, at the meatus of the urinary sphincter in the exemplary embodiment, when the needles44are deployed, the pointed tips44aof those needles extend into the corresponding tissue sites for injection of medicant at each of those tissue sites.

The needles44are able to move within channels40aand within passages80relative to their defining structures and as the needles are moved through tip42, the pointed tip44aof each needle44moves and protrudes out of its corresponding opening78. Ring88is used in order to securely attach onto a portion of each needle so that its pointed tip can be deployed and extended out of its corresponding opening. The attachment between ring88and the needles44is by the use of a suitable adhesive. Ring88is sized and shaped for receipt of the nine (9) needles with one (1) needle each being positioned in each of the nine (9) channels92which are defined by ring88and which extend the full length of ring88. There is one (1) needle44placed in each channel92and each needle is securely bonded in place within ring88using a suitable adhesive. In the exemplary embodiment a UV cured adhesive is used to lock together the ring88and each of the nine (9) needles44. A yoke96(seeFIGS. 17 and 17A) and a trigger98(seeFIGS. 18 and 18A) combine in a cooperatively arranged manner in order to move ring88forward in the direction of tip42. The movement of ring88in a forward direction (toward tip42) advances each needle44in order to deploy the pointed tip44aof each needle into a corresponding tissue site. The combination of ring88, yoke96and trigger98defines the principal components of a control linkage for the deployment of the needle tips.

Referring now toFIG. 13, the details of hub86are illustrated. Hub86is positioned at the proximal end of multi-lumen shaft40, adjacent ring88. Hub86is an annular component defining a generally cylindrical, hollow interior100which receives a portion of shaft40. The larger diameter ends of hub86define a reduced diameter concentric portion102which is centered therebetween. The two (2) halves of the housing including the right half body43and its left half which is a mirror image, fit together, clamping around portion102.

Referring now toFIGS. 15 and 15A, the details of ring88are illustrated. Ring88defines a hollow interior and five (5) generally concentric annular portions104a,104b,104c,104dand104e. Portion104acorresponds to the distal end of ring88in its assembled orientation in device20and portion104ecorresponds to the proximal end. The two larger diameter center portions104band104dare used as abutment surfaces for the engaging portions of yoke96. Other portions of yoke96are engaged by portions of trigger98. As trigger98is manipulated in one mode, the yoke96is moved forward in a distal direction which advances ring88and thus advances the tips44aof each needle44so as to extend outwardly beyond the outer surface of multi-lumen tip42. The nine (9) elongated channels92run substantially parallel to the longitudinal axis of ring88and extend the entire axial length of ring88. Each channel92which has an overall shape which is part-cylindrical is sized so as to be able to receive each needle diameter with sufficient space for receipt of an adequate amount of adhesive so as to securely anchor each of the nine (9) needles into ring88.

Referring now toFIGS. 16, 16A and 16B, the details of barrel35are illustrated. In addition to the structural features already described, each barrel35includes a body portion108which is adjacent the end opposite injection tip37. This body portion108has a sector shape with a curved outer edge110and a generally concave curved inner edge112. The arcuate measurement in degrees is approximately 40 degrees. This means that when all nine (9) barrels35are grouped together into a circular array as is illustrated, into the form of barrel subassembly94, the subassembly form is generally cylindrical. An interior bore or aperture114, defined by the nine (9) inner edges112, opens into a shelf116defined by the nine (9) raised ribs118. Each rib118has a curved inner edge120and a generally concentric curved outer edge122. Edges112and122are at opposite ends of the surface defining aperture114. The cylindrical arrangement of nine (9) inner edges120defines a bore124which is generally coaxial with the internally threaded bore126of hub29. This construction allows the use of a clamping plate (not illustrated) which is applied against shelf116of each of the nine (9) barrels35as part of barrel subassembly94so as to securely clamp the subassembly94against the proximal face of hub29. This clamping structure helps to maintain the generally cylindrical form of barrel subassembly94and keep the tapered fittings seated tightly and/or sealingly connected.

Referring toFIGS. 17 and 17A, but details of yoke96are illustrated. Yoke96, is preferably a single-piece, unitary component which is injection molded from a polymeric material, such as nylon. Yoke96includes two (2) arm portions128aand128bintegrally extending into a distal hub130. Hub130is constructed and arranged with two (2) spaced apart wall portions132and134. These two (2) wall portions define a clearance space136therebetween. This clearance space136is sized and shaped so as to fit down over annular portion104bof ring88. Similarly, wall portion132fits over portion104aof ring88and wall portion134fits over portion104c.

Arm portion128adefines a slot138which receives a clevis-type arm140of trigger98. Arm portion128bdefines a slot142which receives another clevis-type arm144of trigger98. When the trigger is squeezed and pivots about pivot post43b, arms140and144act against abutment surfaces which partially define slots138and142, respectively, so as to advance yoke96in the direction of tip42. This movement of yoke96causes advancing movement of ring88and thereby advancing movement for each needle44which is securely retained and captured within ring88. Slot138is defined by one (1) curved wall and by one (1) substantially flat wall. Slot142is defined by one (1) curved wall and by one (1) substantially flat wall.

Referring toFIGS. 18 and 18A, the details of trigger98are illustrated. Trigger98is preferably a single-piece, unitary component, which is injection molded from a polymeric material, such as nylon. Trigger98includes a gripping portion146, a curved abutment portion148and a clearance aperture150. The unitary body of trigger98defines a clearance hole152for receipt of pivot post43b. Aperture150provides clearance for one (1) of the posts which receives a threaded fastener for joining together the two (2) housing halves (seeFIG. 22). Abutment portion148cooperates with rear lever41(seeFIG. 19) so as to prevent dispensing movement of the nine (9) plunger array39(i.e. forward depression), unless the tips of the needles are extended. Lever41includes a rib154and the positioning of rib154relative to abutment portion148prevents actuation of the lever41for medicant dispensing unless the abutment portion148is moved out of an abutment position, seeFIGS. 2 and 3. Abutment portion148is sized, shaped and positioned such that essentially full deployment of the nine (9) needles44is required before portion148is moved out of an abutment position with rib154which would thereafter allow for the lever41to be used in the advancing movement of nine (9) plunger array39.

Referring toFIGS. 19 and 19A, the details of lever41are illustrated. Lever41is preferably a single-piece, unitary component which is injection molded from a polymeric material, such as nylon. Lever41is actually illustrated as part of a lever assembly155. The lever assembly155further includes a connection bar156, which is attached to lever41using a threaded fastener at each end. Lever41includes gripping portion158and a pivot hub160. Pivot hub160defines a through bore162which receives pivot post43c. Connection bar156extends through the handle opening164of the nine (9) plunger array39(seeFIG. 20). When movement of lever41is permitted by the orientation of trigger98, the connection bar156moves forward in a distal direction. Lever41pivots forward about pivot post43cas the gripping handle166of device20is squeezed. This squeezing action causes pivoting movement of lever41and thereby, advancing movement of plunger array39. This movement causes each plunger39awith its rubber sealing piston168attached, to move through its corresponding medicant chamber36of each barrel35for dispensing medicant through the nine (9) needles44and thereby injecting the medicant into the nine (9) tissue sites.

Referring toFIGS. 20 and 20A, the details of the nine (9) plunger array39are illustrated. Plunger array39is preferably a single-piece, unitary component which is injection molded from a polymeric material, such as ABS, polyethylene or HDPE. Plunger array39includes a base170and a handle172joined to the base170. Handle172defines handle opening164. The nine (9) plungers39aare each similarly sized and shaped and equally spaced in a cylindrical array as shown inFIG. 20A. The tip174of each plunger39ahas a hub-like shape with an enlarged head176and a similarly sized base178. A reduced diameter post180is positioned therebetween. The combination of plunger array39and the nine (9) cooperating barrels35comprises the primary construction of the “syringe” of device20.

A hollow sealing piston168(seeFIG. 21) is snapped onto each tip174. Each sealing piston168(nine (9) total) is sized and shaped to securely fit onto its corresponding tip174. A preferred material for the single-piece, unitary construction of sealing piston168is silicone rubber or polyisoprene. The size and shape of each head portion182are selected for a snug fit into the medicant chamber36of each barrel35. End184is open for receiving tip174. The size and shape selection for the referenced snug fit are important, as would be understood as part of conventional syringe technology. It is important as the individual plungers and pistons travel through each corresponding medicant chamber that the medicant present in that chamber be dispensed out through the tip and thereafter through the corresponding needle without any noticeable reverse leakage of the medicant past the edges of the head portion182of sealing piston168.

Referring toFIG. 23, the details of one of the nine needles44are illustrated. End44cis the portion which is adhesively connected to the corresponding barrel35. The loop44bserves the function of providing additional length between end44cand open tip44aso that tip44ais able to move independently of the fixed position of end44c. The curved loop44bmay also provide a spring-biasing function to aid in the returning of trigger98to its starting position. Trigger98is squeezed toward lever41when it is intended to move yoke96and thereby advance the tips44aof the needles. This movement tries to more tightly coil the loop44bor tries to flex the loop44bof each needle. The stiffness and memory of the needle metal causes each needle to try and restore the shape of the loop. This creates a type of spring return which pulls back on ring88and thus pulls back on yoke96.

If the spring forces are sufficient to effect this movement, the trigger will return to its starting position once the gripping force of the user is removed. An additional spring may be located in the handle of device20if the needles alone are not sufficient for a “spring return” of the trigger.