Abstract:
A device that uses an anatomic landmark or fiduciary point to establish a point of origin for device orientation in space is provided. The device controls the direction and depth of delivery of a needle, wire, trocar or cannula utilized for diagnostic or therapeutic intervention. The device guides the percutaneous delivery of a needle, wire, trocar or cannula to a target spatial location on or within tissue.

Description:
CROSS REFERENCE OF RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. provisional application Ser. No. 62/069,597, filed on Oct. 28, 2014; the entirety of which is hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to a method and device for the controlled delivery of medical devices. More specifically, the present invention relates to a device for controlling the percutaneous delivery of needles, fine wires, electrodes, trocars or cannulas to a target location in a patient. 
       BACKGROUND OF THE INVENTION 
       [0003]    Physicians like neurologists and urologists, physiatrists, physical therapists, chiropractors, and other medical providers have used nerve and muscle stimulation to treat a variety of ailments. These medical providers have used various methods of neurostimulation and neuromodulation such as implanted electrical and optical devices and external electrical, magnetic and ultrasonic devices for treatments such as deep brain stimulation for Parkinson&#39;s disease and electronic muscle stimulation (EMS) and transcutaneous electrical nerve stimulation (TENS) for muscle and joint rehabilitation as well as chronic pain. Urologists and obstetrician/gynecologists have used a form of TENS for pelvic floor stimulation to treat urge incontinence, urinary frequency, non-obstructive urinary retention, interstitial cystitis, chronic pelvic pain, anal incontinence and other pelvic neuromuscular disorders. 
         [0004]    Transcutaneous stimulators, i.e., stimulators which do not physically penetrate the skin surface, are less invasive than percutaneous and implantable stimulators. However, transcutaneous stimulators often require higher current levels than percutaneous and implantable stimulators. Higher current levels can cause irritation and discomfort when used for extended periods. Also, since transcutaneous stimulators stimulate on the skin surface, their target site usually covers a large area. Thus, transcutaneous stimulators may not be highly effective for direct nerve stimulation. This is especially true for stimulation targets that are deep to the skin surface and that may be shielded by overlying hard tissue. 
         [0005]    More typically, providers use implantable stimulators when there is a need for direct nerve stimulation or continuous stimulation. Implantable stimulators can free a patient from the need for constant and frequent manual treatment. However, implantable stimulators can cause mild discomfort, and often cause more severe implant-site pain. 
         [0006]    Percutaneous stimulators provide direct nerve stimulation without the invasiveness of an implant. During treatment, a conducting needle is inserted to provide electrical stimulation to a target nerve. The needle is electrically connected to a controller by a series of leads, often bound together at one end as a cable that connects to the controller. When positioned properly, the needle (which includes a receiver/electrode assembly) stimulates the tibial nerve thereby modulating nerve activity in the sacral plexus. Modulation or interruption of sacral nerve activity is useful in the treatment of the pelvic heath disorders enumerated above. 
         [0007]    However, the needle must be precisely and accurately positioned to achieve the maximum heath benefit. There are currently no devices that facilitate or guide accurate percutaneous delivery of a needle, wire, trocar or cannula to a target spatial location on or within tissue that can be utilized by both medical personnel and patients. 
         [0008]    Therefore, what is needed is a device that uses an anatomic landmark or fiduciary point to establish a point of origin for device orientation in space. What is also needed is a device that can control the direction and depth of delivery of the needle, wire, trocar or cannula that is part of the diagnostic or therapeutic intervention. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    The problems associated with conventional means of delivering and guiding a needle to an anatomic site are addressed by the present invention. 
         [0010]    In certain aspects the present invention, precisely and accurately guides the percutaneous delivery of a needle, wire, trocar or cannula to a target spatial location on or within tissue. 
         [0011]    In other aspects, the delivery device uses an anatomic landmark or fiduciary point to establish a point of origin for device orientation in space. 
         [0012]    In other aspects the present invention controls the direction and depth of the delivery and placement of the needle, wire, trocar or cannula on or into tissue. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: 
           [0014]      FIG. 1  is a perspective view of an exemplary delivery device in accordance with the invention. 
           [0015]      FIG. 2A  is an exploded view of the exemplary device illustrated in  FIG. 1 . 
           [0016]      FIGS. 2B through 2E  show various aspects of the exemplary device illustrated in  FIG. 2A  and  FIG. 1 . 
           [0017]      FIG. 3A  is a side view of a needle advancement device in accordance with the invention. 
           [0018]      FIG. 3B  is a side detailed view of the needle advancement device of  FIG. 3A . 
           [0019]      FIG. 4  is a side view of one aspect of a needle advancement device in accordance with the invention. 
           [0020]      FIG. 5  is a side view of another aspect of a needle advancement device in accordance with the invention. 
           [0021]      FIGS. 6A and 6B  are perspective views of one aspect of a needle advancement device in accordance with the invention. 
           [0022]      FIGS. 7A and 7B  are perspective views of one aspect of a needle advancement device in accordance with the invention. 
           [0023]      FIGS. 8A and 8B  are perspective views of one aspect of a needle advancement device in accordance with the invention illustrating a wedged collar and a wedged pusher, respectively. 
           [0024]      FIGS. 9A through 9E  are perspective views of one aspect of a needle advancement device in accordance with the invention illustrating the complete assembly of the device in  FIG. 9A  and the various component parts in  FIGS. 9B through 9E . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0025]    Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which this invention belongs. 
         [0026]    Referring now to  FIGS. 1-2E  the delivery device  10  in accordance with the invention broadly includes circular positioning ring  12 , rotational element  14 , directional element  16  and coupling mechanism  18 . 
         [0027]    Circular positioning ring is configured to circumscribe the medial malleolus, the bony prominence on the inner side of the ankle formed by the lower end of the tibia, at a preferred height. Circular positioning ring  12  includes one or more vertical receiving channels  20 ,  22  operably coupled to lower horizontal receiving channel  24 . Cone-shaped rotational element  14  includes one or more flanges  26 ,  28  that are received by vertical receiving channels  20 ,  22  in mating relationship and operably engage with lower horizontal receiving channel  24 . A manual rotational force applied to rotational element  14  will cause flanges  26 ,  28  to travel in lower horizontal receiving channel  24  until a stop is encountered, causing the rotational element to cease rotation at that position, with the possible additional feature of being locked into the circular ring. Rotational element  14  includes a cap portion  38  having an internal threaded lumen  40 . 
         [0028]    Circular positioning ring includes a base  11 . Base  11  may incorporate the use of a sheet or ring of adhesive tape to removably secure the device  10  over the medial malleolus while in use. In alternative aspects of the invention a band or collar (not shown) may extend from the circular ring  12  and circumscribe the surface of the foot, ankle and heel such that the entire device  10  assembly is centered on the medial malleolus. The band or collar may be held in place by fastening means known to those of skill in the art such as Velcro, adhesives, mechanical fasteners and combinations thereof. 
         [0029]    Coupling mechanism  18  includes cone-shaped base  30  and shaft  32 . In operation, cone-shaped base  30  is configured to be positioned externally over the medial malleolus. Shaft  32  may be integrally formed with or threadably received by base  30 . If threadably received by base  30 , shaft may be dimensioned such that the outer diameter of shaft  32  is less that the inner diameter of threaded lumen  40 . Shaft  32  includes a needle, or needle guide and driver device, receiving lumen therethrough  34  and a threaded top portion  36 . In one aspect of the invention, threaded top portion  36  is threadably received by threaded cap  38  operably coupling rotational element  14  with coupling mechanism  18 . 
         [0030]    Directional element  16  broadly includes vertical shaft  42 , adjustable positioning arm  44  and needle guide assembly  48 . Vertical shaft includes a lumen  50  whose inner diameter is greater than the outer diameter of cap portion  38 . Lumen  50  is pivotably received by cap portion  38 . Those of skill in the art will appreciate that the lumen  50  may extend the length of shaft  42  or in other embodiments may be slightly greater than or equal to the vertical depth of cap portion  38 . 
         [0031]    Adjustable positioning arm  44  includes a right angle adjustable construction. To accommodate different patient anatomies, adjustable positioning arm  44  may be adjusted to a plurality of different acute angles, preferably from 30-60 degrees offset from the longitudinal axis of shaft  42 , by a ratcheting mechanism (not shown). 
         [0032]    Guide tube  48  is operably coupled to adjustable arm  44 . Guide tube  48  operates to position a thin gauge, non-hypodermic needle to the target location near the tibial nerve which enable the neurostimulation therapy to be delivered. Referring now to  FIGS. 3-5  various aspects of guide tube geometry are illustrated. 
         [0033]    Guide tube  48  operably receives a PTNS needle advance device  60  as best seen in  FIGS. 3A-5 . The PTNS needle advancement device enables the controlled advancement and delivery of a needle. In one aspect for the delivery of percutaneous tibial nerve stimulation (PTNS) therapy, the PTNS needle advance device  60  is designed to linearly and controllably advance a PTNS needle electrode through the surface of the skin of the lower leg proximate the medial malleolus to a target depth within the tissue to enable the clinically effective delivery of tibial neuromodulation. 
         [0034]    As best seen in  FIGS. 3A and 3B  one aspect of a PTNS needle advancement device is illustrated. Needle advance device  60  broadly includes acupuncture needle  62  housed within cylindrical sheath  64 . The needle advance device  60  includes the ability to translate the acupuncture needle  62  linearly through the inner diameter (ID) of the sheath or tube. Cap  70  of the needle advance device  60  fits over the proximal end of the cylindrical sheath  64 . Cap  70  includes a double-headed piston with one piston head that has a diameter greater than the I.D. of the guide tube and another piston head that has a diameter that is less than the I.D. of the guide tube. The length of the piston shaft, which also has an O.D. smaller than the I.D. of the guide tube, between the two piston heads determines the maximum length of advancement of the piston through the I.D. or lumen of the guide tube. The piston is propelled within the cap by means of spring  72 . Those of skill in the art will appreciate that other means of propulsion may be incorporated into the device such as hydraulic, percussive, magnetic, electromagnetic, compressed fluids and the like. A locking mechanism  66  may be incorporated into the cap  70  or into the guide tube/needle holder element  48  to prevent undesired needle translation or movement within the cylindrical sheath  64 . Cap  70  is rotatably or threadably received on cylindrical sheath  64 . Spring  72  has a spring constant that allows spring to advance needle  62  as rotational or other force is applied by cap  70 . The locking mechanism  66  may be contained within a single component or may be contained in separate components of the controlled advancement and delivery device. Locking mechanism  66  may be a simple interference fit of a removable component that is insertable between the ID of the cap (or the guide tube/needle holder) and the OD of the needle. When the locking component is in place, the interference fit keeps the needle from moving freely. Once it is removed, the needle is free to move within the guide tube or cap plus guide tube construct. 
         [0035]    Referring now to  FIG. 4 , with like elements being labeled with like reference numerals, one aspect of a controlled advancement and delivery device  80  for a PTNS needle electrode is illustrated. A 34 gauge acupuncture needle  62  is received in a cylindrical sheath  64  of uniform or varying cross section area. The cylindrical sheath  64  may be opaque and includes inner cross-sectional dimensions larger than the maximum outer cross-sectional dimension of the acupuncture needle along its entire length or along only a portion of its length. In one aspect of the controlled advancement and delivery device for a PTNS needle electrode  80 , the 34 gauge acupuncture needle  62  is placed in a cylindrical sheath  64  with a uniform circular cross-section. The sheath  64  has an inner diameter that is larger than the maximum outer diameter of the acupuncture needle. Tabs  84  are interposed between the outer surface of the acupuncture needle and the inner surface of the cylindrical sheath and serve to lock and/or controllably advance the position of the needle by means of a frictional or interference fit. Tabs  84  may be juxtaposed in a parallel relationship or may alternatively be staggered. Tabs  74  may be broken or retracted which in turn allows the acupuncture needle to advance freely within the cylindrical sheath  62  to the next set of tabs  74 . The tabs can be broken or retracted via the linear advance of a cap feature that progresses along the outside of the sheath/needle holder element. This is a feasible design but not our first choice due to cost reasons. 
         [0036]    Referring now to  FIG. 5  another aspect of a controlled advancement and delivery device  90  for a PTNS needle electrode  92  is illustrated. Cap  70  including a controlled advancement mechanism  75  fits over one end of the cylindrical sheath  64 . Controlled advancement mechanism  75  broadly includes first and second piston heads  92 ,  94  and spring  72  interposed therebetween or between cap  70  and first piston head  92 . First piston head  92  has a diameter greater than the I.D. of the cylindrical sheath  64  and second piston head  94  has a diameter that is less than the I.D. of the cylindrical sheath  64 . The length of the piston shaft, i.e. the length extending from the proximal tip of the first piston head  92  to the distal tip of the second piston head  94 , which also has an O.D. smaller than the I.D. of the cylindrical sheath  64 , between the first and second piston heads determines the maximum length of advancement of the piston through the I.D. or lumen of the cylindrical sheath  64 . The first and/or second piston head may be propelled within cap  70  by means of spring  72 . Those of skill in the art will appreciate that other means of propulsion may be employed such as hydraulic, percussive, magnetic, electromagnetic, compressed fluids and the like. In one aspect the double headed piston  92 ,  94  may be propelled by compressing spring  72 , which is then allowed to elongate in stages, driving the second and or first and second piston heads forward in stages. The second and/or first and second piston heads thus advance in a controlled fashion until the outer diameter of the piston head cannot pass the point of interference or the smaller I.D. of the cylindrical sheath  64 . Those of skill in the art will appreciate that the piston is a unitary double headed construction, and both heads undergo movement under the action of the propulsive mechanism, which acts against the first piston head and causes the entire unit to move forward. The piston head with the diameter that is smaller than the I.D. of the cylindrical sheath  64  is in contact with the head of the acupuncture needle, ensuring that the movement of the double headed piston also results in linear and controlled advancement of the acupuncture needle to a desired depth. The cap or the outer telescoping head also incorporates a means to specify the maximum distance of advancement of the piston and, thus, of the needle electrode that is driven by the piston. The maximum distance of advancement required for the accurate positioning of the needle electrode for PTNS can be determined from anatomical measurements; for example, it can be based on the medio-lateral diameter of the lower calf of the human leg, just above the ankle. After the needle electrode  62  has reached the target tissue location, the cylindrical sheath  64  and the cap or telescoping outer tube  70  can be withdrawn, leaving the needle electrode accessible for making the electrical connections required to deliver PTNS. 
         [0037]    Referring now to  FIGS. 6A and 6B  perspective views of one aspect of a needle advancement device in accordance with the invention are illustrated. 
         [0038]    Referring now to  FIGS. 7A and 7B  perspective views of another aspect of a needle advancement device in accordance with the invention are illustrated. 
         [0039]    Referring now to  FIGS. 8A and 8B  perspective views of a further aspect of a needle advancement device in accordance with the invention illustrating a wedged collar and a wedged pusher, respectively, are illustrated. 
         [0040]    Referring now to  FIGS. 9A through 9E  perspective views of a further aspect of a needle advancement device in accordance with the invention are shown. Illustrated in  FIG. 9A  is the completed assembly of the device and the various component parts in  FIGS. 9B through 9E . 
         [0041]    Although the present invention has been described with reference to certain aspects and embodiments, those of ordinary skill in the art will appreciate that changes may be made in form and detail without departing from the spirit and scope of the invention.