Abstract:
A system for tissue augmentation using a thin-walled needle. The system includes a thin-walled needle and a syringe. The system further includes a plurality of particles for injection into a desired tissue to be augmented. The thin-walled needle has an inner diameter sufficient to allow for passage of the particles and an outer diameter designed to minimize the puncture wound in the skin when the needle is inserted. The particles may be suspended in a carrier.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates generally to the field of tissue augmentation systems. Prior art needles typically utilize established dimensions. Generally these prior art needles have been designed for injecting fluids. Typically the size of the puncture by the needle is not of concern. 
       SUMMARY OF THE INVENTION 
       [0002]    One embodiment of the invention relates to a system for augmenting tissue comprising a needle assembly and tissue augmentation material. The needle assembly includes a hub and a needle. The hub has a first end for engaging the syringe and a second end for engaging the needle. The needle comprises a hallow shaft with a first end and a second end, each end having an opening respectively into an interior volume of the hallow shaft, the first end engaging the second end of the hub and a second end having a pointed tip. The hallow shaft having an outer surface and an inner surface, with a thickness of material there between, the outer surface having a nominal diameter of about 0.353 mm to about 0.367 mm and the inner surface having a nominal diameter of about 0.198 mm to about 0.244 mm, with the nominal thickness of material being about 0.062 to about 0.078 mm. The tissue augmentation material may, in one embodiment, comprise particles suspended in a carrier, wherein the material may be positioned in the syringe. Optionally, the tissue augmentation material can be included in an enclosure. In a further embodiment, the material is transferred to a syringe from a container immediately prior to administration to a patient. 
         [0003]    In another embodiment, the invention relates to a kit for augmenting tissue. The kit includes an enclosure having tissue augmentation material disposed therein, and a hub and needle attached to the syringe. The hub has a first end for engaging the syringe and a second end for engaging a needle. The needle comprises a hallow shaft with a first end and a second end, each end having an opening respectively into an interior volume of the hallow shaft, the first end engaging the second end of the hub and a second end having a lancet. The hallow shaft has an outer diameter and an inner diameter, with a thickness of material there between, the outer surface having a nominal diameter of about 0.353 mm to about 0.367 mm and the inner surface having a nominal diameter of about 0.198 mm to about 0.244 mm, with the nominal thickness of material being about 0.062 to about 0.078 mm. The tissue augmentation material is injected into a tissue to be augmented via the needle. 
         [0004]    In yet another embodiment, the invention relates to a system for augmenting tissue comprising a needle assembly having a hub and a needle. The hub has a first end for engaging a syringe and a second end for engaging a needle. The needle comprises a hallow shaft with a first end and a second end, each end having an opening respectively into an interior volume of the hallow shaft, the first end engaging the second end of the hub and a second end having a lancet. The hallow shaft has an outer diameter and an inner diameter, with a thickness of material there between, the nominal outer diameter being about 0.0.367 mm and the nominal inner diameter of about 0.0.244 mm, with the nominal thickness of material being about 0.078 mm. A plurality of injectable particles are suspended in a carrier and disposed in the syringe, the plurality of particles having a size distribution within the range of 15 microns to about 65 microns. 
         [0005]    In one embodiment, the outer surface of the needle has a nominal diameter of about 0.353 mm (about that of a 28 gauge needle) and the inner surface having a nominal diameter of about 0.198 mm (about that of a 27 gauge needle). In another embodiment, the outer surface of the needle has a nominal diameter of about 0.305 mm (about that of a 30 gauge needle) and the inner surface having a nominal diameter of about 0.198 mm (about that of a 27 gauge needle). In another embodiment, the outer surface of the needle has a nominal diameter of about 0.406 mm (about that of a 27 gauge needle) and the inner surface having a nominal diameter of about 0.254 mm (about that of a 25 gauge needle). 
         [0006]    The invention includes certain features and combinations of parts hereinafter fully described, illustrated in the accompanying figures, described below, and particularly pointed out in the appended claims, it being understood that various changes in the details may be made without departing from the spirit, or sacrificing any of the advantages of the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1   a  is an illustration of one embodiment of a tissue augmentation system;  FIG. 1   b  is an closeup of the augmentation material contained in the syringe of  FIG. 1   a;    
           [0008]      FIG. 2  is an illustration of the needle assembly and syringe of  FIG. 1 ; 
           [0009]      FIG. 3   a  is a partial perspective view of one embodiment of a needle;  FIG. 3   b  is a cross-sectional view of the needle of  FIG. 3   a  along line A-A; and 
           [0010]      FIG. 4  illustrates a kit containing a needle assembly, a syringe, and a container, the container filled with augmentation material. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0011]    The present invention relates to a needle  111  for use in delivery of augmentation material  106  and kits for providing same. The kit includes a needle  111  as described below and augmentation material  106 . In one embodiment, as  FIG. 1   a  illustrates, a delivery system  101  is provided. The delivery system  101  includes a needle assembly  103  and a syringe  105  and augmentation material  106 . The needle assembly  103  and syringe  105  are in fluid communication such that, in general, the syringe  105  serves to contain the material  106  (best shown in  FIG. 1   b ), which is ejected from the syringe  105  through the needle assembly  103  and injected into a target tissue to be augmented. 
         [0012]    In various embodiments, the augmentation material  106  comprises a plurality of small particles  107 . Various such particles  107  are known in the art. Particles  107  used in the delivery system  101  may be formed from “non-biodegradable”, “biodegradable” (by the body) materials or combinations thereof. The particles  107  may include, but are not limited to, silicone gel, Teflon paste, bioplastics including polymerized silicone particles dispersed in polyvinylpyrrolidone, carbon-coated substrate particles comprised of metallic cores, glass, ceramics, microspheres comprising acrylic polymers, acrylate polymers including polymethacrylate, polymethylmethacrylate, poly-L-lactic acid, sodium acrylate polymer, acrylamide polymer, acrylamide derivative polymer or copolymer, sodium acrylate and vinyl alcohol polymers, isobutylene-maleic anhydride crosslinked copolymer, starch-acrylonitrile graft copolymer, crosslinked sodium polyacrylate polymer, crosslinked polyethylene oxide, polylactides such as polylactic acides, polyglycolides, or copolymers thereof and polysaccharides including cellulose such as carboxymethylcellulose, ethylcellulose, hydroxylpropyl cellulose, and hyaluronic acid, alginates, chitosan, gelatin, and silicones, hydrogels, glass and the like. 
         [0013]    In an exemplary embodiment, the particles  107  are ceramic based composites. Particulate ceramic materials that can be used to form the particles  107  include, but are not limited to, calcium hydroxyapatite, and other suitable materials including, but are not limited to, calcium phosphate-based materials, alumina-based materials and the like. Examples include, but are not limited to, tetracalcium phosphate, calcium pyrophosphate, tricalcium phosphate, octacalcium phosphate, calcium fluorapatite, calcium carbonate apatite, and combinations thereof. In one embodiment, the ceramic particles are smooth, rounded, substantially spherical, particles of a ceramic material embedded in a biocompatible gel material that is continuous, cross linked or in a dehydrated configuration as discussed below. 
         [0014]    In one embodiment, the particles  107 , such as those embodiments described above, are suspended in a “carrier”  108 . In an exemplary embodiment, the carrier  108  supports the particles  107 , facilitating injection through the needle assembly  103 . In one embodiment, the carrier  108  forms an integral and compatible part, along with the particles  107 , of the implant (and surrounding bioenvironment) once injected. The carrier  108  may be non-biodegradable, biodegradable or a combination thereof. In one embodiment, the carrier  108  may be water. The carrier  108  may further include additives such as collagen. 
         [0015]    In one embodiment, the carrier  108  comprises a gel. In a further embodiment, the gel of the present invention exhibits characteristics that modifiable to mimic the physical, chemical and properties of the implant location. Such characteristics include, but are not limited to, extrusion, rheological physical/mechanical parameters, decomposition rate (chemical and physical), moldability, mechanical performance and porosity to modulate tissue response. Gel characteristics control varying rates of resorption, as host tissue forms around the slower resorbing ceramic particles. 
         [0016]    The carrier  108  comprises, in one exemplary embodiment, a polymer gel. In one embodiment, the gel is a polysaccharide gel. Polysaccharides that may be utilized in the present invention include, for example, any suitable polysaccharide within the following classes of polysaccharides: celluloses/starch, chitin and chitosan, hyaluronic acid, hydrophobe modified systems, alginates, carrageenans, agar, agarose, oligosaccharide and macrocyclic systems. Examples of polysaccharides grouped into four basic categories include: 1. nonionic polysaccharides, including cellulose derivatives, starch, guar, chitin, agarose and. dextron; 2. anionic polysaccharides including cellulose derivatives starch derivatives, carrageenan, alginic acid, carboxymethyl chitin/chitosan, hyaluronic acid and xanthan; 3. cationic polysaccharides, including cellulose derivatives, starch derivatives guar derivatives, chitosan and chitosan derivatives (including chitosan lactate); and 4. hydrophobe modified polysaccharides including cellulose derivatives and alpha-emulsan. Preferred polysaccharides for use in the present invention include, for example, carboxymethylcellulose, agar methylcellulose, hydroxypropyl methylcellulose, ethylcellulose, microcrystalline cellulose, oxidized cellulose, chitin, chitosan, alginic acid, sodium alginate, and xanthan gum. 
         [0017]    Various embodiments of the carrier  108  comprise a gel having crosslinkable components. In such embodiments, appropriate gel cross linkers may, include, but are not limited to: heat, pH, cross-linking through mono valent, di-valent and tri-valent cationic interactions. The cross linking ions used to crosslink the polymers may be anions or cations depending on whether the polymer is anionically or cationically cross linkable. Appropriate cross linking ions include but are not limited to cations selected from the group consisting of calcium, magnesium, barium, strontium, boron, beryllium, aluminum, iron, copper, cobalt, and silver ions. Anions may be selected from but are not limited to the group consisting of phosphate, citrate, borate, carbonate, maleate, adipate and oxalate ions. More broadly, the anions are derived from polybasic organic or inorganic acids. Preferred cross linking cations are calcium iron and barium ions. The most preferred cross linking cations are calcium and iron. The preferred cross linking anions are phosphate, citrate and carbonate. Cross linking may be carried out by contacting the polymers with an aqueous solution containing dissolved ions. Additionally, cross-linking could be accomplished through organic chemical modification including: poly-functional epoxy compound is selected from the group consisting of 1,4-butanediol diglycidyl ether (BDDE), ethylene glycol diglycidyl ether (EGDGE), 1,6-hexanediol diglycigyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polytetramethylene glycol digylcidyl ether, neopentyl glycol digylcidyl ether, polyglycerol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, tri-methylolpropane polyglycidyl ether, pentaerythritol polyglycidyl ether, and sorbitol polyglycidyl ether. Additionally, cross-linking could be accomplished through organic chemical modification through the carbonyl or hydroxide functionality of the polysaccharide backbone reaction. 
         [0018]    In one embodiment, the gel is carboxymethylcellulose (“CMC”) based with concentration ranges from 0.1% to 10%, preferably from 1.5% to 5% band most preferably from 2% to 3%. Material  106  may be mixed to create composite gels with compositional ranges for each component between 0.1% to 5%. Glycerin or the like or other space occupying filler (including ionic components and other organic/inorganic non reactive components) may be added to the composition and range from 0.1% to 5%. 
         [0019]    The particles  107 , such as those discussed above, alone, or in combination with a carrier  108 , as discussed previously, are injected via a syringe  105  and needle assembly  103 .  FIGS. 1-3  illustrates the needle assembly  103  includes a needle  111  (shown in detail in  FIG. 3 ) and a hub  121 . The needle  111  comprises a hallow shaft  113  having a first end  114  through which material  106  exits the needle (i.e., positioned distal the hub  121 ) and a second end  115  for engaging the hub  121  (i.e., proximate the hub  121 ). The first end  114  may include a bevel  116 . The bevel  116  is a tapered portion of the shaft  113  forming a point  117 . In one embodiment, the shaft  113  includes more than one bevel  116 , the first to create a taper to slim a diameter of the needle proximate the first end  114  and the second to create the point  117  for piercing the tissue. 
         [0020]    The hallow shaft  113  includes an inner diameter  118  and an outer diameter  119  with a thickness  120  there between. The inner diameter  118  provides a fluid flow path for the material  106  to pass through the needle  111 . It will be appreciated that smaller inner diameters will result in a more restrictive flow of fluid and will limit the type of materials extrudable from the needle  111 , for example suspended particles  107  above a certain size. 
         [0021]    The outer diameter  119  of the needle  111  reflects the size of the hole the needle  111  will puncture in the tissue. The larger the outer diameter  119 , the larger the puncture in the tissue. 
         [0022]    In one embodiment, the outer diameter  119  is minimized while the inner diameter  118  is maximized. In this embodiment, the thickness  120  is sufficient to impart structural support to the needle  111 . Thus, the thickness  120  must be such that the needle  111  can support its own weight and that of material  106  being extruded therefrom. 
         [0023]    In one embodiment, the needle  111  has an outer diameter  119  that is sized to approximately equal the outer diameter of a first standard needle gauge while the inner diameter  118  is sized to approximately equal the inner diameter  118  of second, larger, standard needle gauge. In another exemplary embodiment, the outer surface having a nominal diameter of about 0.353 mm to about 0.367 mm and the inner surface having a nominal diameter of about 0.198 mm to about 0.244 mm, with the nominal thickness of material  106  being about 0.062 to about 0.078 mm. In one embodiment, the outer surface of the needle has a nominal diameter of about 0.353 mm (about that of a 28 gauge needle) and the inner surface having a nominal diameter of about 0.198 mm (about that of a 27 gauge needle). In another embodiment, the outer surface of the needle has a nominal diameter of about 0.305 mm (about that of a 30 gauge needle) and the inner surface having a nominal diameter of about 0.198 mm (about that of a 27 gauge needle). In another embodiment, the outer surface of the needle has a nominal diameter of about 0.406 mm (about that of a 27 gauge needle) and the inner surface having a nominal diameter of about 0.254 mm (about that of a 25 gauge needle). In one embodiment, the outer diameter of the needle  111  may be selected from the above range and a desired thickness of the needle selected, the thickness structurally sufficient for an intended use, and the inner diameter determined from those two selected measurements. 
         [0024]    In one embodiment, particles  107  may range in size about 15 microns to about 65 microns. Preferably from about 15 microns to about 55 microns, more preferably from about 15 microns to about 50 microns, and most preferably about 25 microns to about 45 microns. Concentration of ceramic particles  107  ranges from 5% to 65%, preferably from 10% to 50% and most preferably from 30% to 45%. 
         [0025]    In one embodiment, the needle  111  is affixed to the hub  121  with an adhesive, such as but not limited to epoxy. 
         [0026]    The syringe  105  includes a body  131  and a plunger  132 . The body  131  further includes a body  131 , a plunger opening  135  at a first end  136  and a needle connection mechanism  137 , with a passage from the body  131  therethrough, at second end  138 . The plunger  132  forms a seal with the inner surface of the body  131  such that movement of the plunger  132  into the body  131  will force the contents through the second end  138 . The needle assembly  103  connects with the second end  138  via mechanisms known in the art so as to place the needle assembly  103  in fluid communication with the chamber of the body  131 . In exemplary embodiments the mechanisms for connecting the needle assembly  103  and the syringe  105  include, but are not limited to, luer locks, threads, and “snap-fit” mechanisms. 
         [0027]    In an exemplary embodiment, a kit (one embodiment shown in  FIG. 4 ) is provided containing the needle and an enclosure  160  having a volume of augmentation material  106 . In one embodiment the kit includes sufficient augmentation materials  106  for at least one usage for a give application, i.e., a “single application amount”. In one embodiment, the volume of particles  107  included in the kit varies depending on the intended application. In various embodiments, applications include, but are not limited to: providing tissue implant product throughout the body  131 , such as, for example, urinary tract, vocal fold, lip tissue, cheek, other dermal tissue for various uses including clinical and restorative applications and cosmetic applications like augmenting nasolabial folds, nasolabial crease, marionette lines, lip augmentation and augmenting skin wrinkles and folds.  FIG. 1  illustrates one such kit. 
         [0028]    In one embodiment, the kit may include a one or more needles  111  in combination with the augmentation materials  106 . It should be appreciated that the number of needles  111  provided with the kit can be varied as needed, such as providing two needles with a single syringe  105  and augmentation material  106  to provide a second needle in the event the first needle becomes contaminated. Likewise, in one embodiment the kit may include a needle  111  for each single application amount included in the kit, either in separate syringes  105  or containers  161  as described further below. 
         [0029]    The material  106  may be pre-packaged into the syringe  105  in the kit. Alternatively, the material  106  may be provided in a container  161  as part of the kit, with an empty syringe  105  provided as well. In a further alternative embodiment, the material  106  may be provided pre-packed into a syringe  105  with additional material  106  in a container  161  or pre-packaged into additional syringes  105 . In one embodiment, as discussed above, the amount of material  106  provided in the pre-packed syringe  105  or a container  161  is sufficient for a single application. Alternatively, the material  106  provided in a container  161  with the kit may include sufficient material  106  for multiple applications. 
         [0030]    In one embodiment, shown in  FIG. 1 , a sheath may be provided for covering the needle. The sheath  150  serves to maintain sterility of the need and to provide protection against physical damage of the needle or injury to a person handling the needle assembly  103 . The sheath  150  comprises a hollow body  151  slightly longer than the length of the needle, so that the needle  111  can be completely disposed within the sheath  150 . The sheath  150  further includes a retention mechanism  153  for retaining the sheath  150  on the needle assembly  103 . Such retention mechanism  153  may include engaging the hub  121  by, but not limited to, “snap-fit”, threads, latches, and “friction fit” mechanisms. 
         [0031]    Certain embodiments of the syringe  105  may include indicia  125  for providing a user with an indication of the volume of particles  107  present in the syringe. 
         [0032]    The foregoing description of embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the present invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the present invention. The embodiments were chosen and described in order to explain the principles of the present invention and its practical application to enable one skilled in the art to utilize the present invention in various embodiments, and with various modifications, as are suited to the particular use contemplated.