Abstract:
A bulking agent is accurately administered into body tissue surrounding the urethra of a patient to support a urinary sphincter muscle and facilitate enhanced control over urination. Preferably, the bulking agent is inserted by use of a catheter which is anchored with a balloon in the bladder. The balloon contacts the bladder neck and locates the position of a needle which is extended from the catheter into the tissue. Consequently, the bulking agent is injected at a position relative to the bladder neck which is very effective in supporting the sphincter muscle. The catheter is rotated in rotational increments to introduce the bulking agent in multiple positions in an annular ring surrounding the urethra.

Description:
TECHNICAL FIELD OF THE INVENTION  
       [0001]     This invention concerns a method and device for the treatment of incontinence, and more particularly to delivering a bulking agent in a reliable position for achieving the best effect, preferably by using a treatment catheter comprising an expandable container attached at a front section for maintaining the treatment catheter in a fixed position for injecting the bulking agent.  
       STATE OF THE ART  
       [0002]     Urinary incontinence effects lifestyle in a dramatic manner. For many it means wearing damp undergarments, diapers, having skin irritation or diaper rash. It limits physical activity, social relationships, sexual attitudes, the ability to do spontaneous activities without careful planning, and in severe circumstances, may lead to a lonesome, hermit-like existence. Drug therapy, exercise programs, and biofeedback techniques have helped some patients, but a need for better treatment still remains. Stress incontinence due to a weakening of the pelvic floor muscles, often after childbirth, is one common cause of female incontinence.  
         [0003]     Another treatment method is a technique called tension-free vaginal tape (TVT). The tape acts as a net around the neck of the bladder and supports it like a hammock. The tape is surgically inserted through the vagina to support the urethra, in a procedure that may last about 30 minutes. While the surgical procedure can be performed under general, regional, or local anesthesia, many surgeons prefer to use local anesthesia. After surgery, the tape will support the urethra during a sudden movement such as a cough or sneeze. The added support from the tape allows the urethra to remain closed and prevents the involuntary loss of urine. As is typically the case, the surgery may lead to problems and should be avoided for some categories of patients.  
         [0004]     Treatment of urinary incontinence through endoscopic procedures using bulking agents has attained popularity in recent years. Dextranomer is effective as a nonimmunogenic bulking agent for the endoscopic treatment of urinary incontinence in the pediatric population, according to new research. Dextranomer is a synthetic co-polymer that has been used successfully for the treatment of vesico-ureteral reflux.  
         [0005]     A 1% hyaluronan solution called DEFLUX has been used as a bulking agent for the treatment of urinary incontinence. Normally, an average of 2.5 cc of DEFLUX is endoscopically delivered to patients via a 4 F cannula at the bladder neck. For males delivery is made along the posterior urethra. DEFLUX has been used also for the treatment of vesicoureteral reflux (malformation of the urinary bladder) in children. Another medical implant, called NASHA (Non-Animal Stabilized Hyaluronic Acid) is used in a similar way.  
         [0006]     Still another material is ZUIDEX which is intended for treatment of stress incontinence. ZUIDEX contains hyaluronic acid—a sugar molecule that is found in most tissues and bodily fluids where it provides structure and lubrication—and dextranomer—a sugar derivative that has been used for wound healing. It is injected into the urethra wall as a gel. An injecting device comprising four syringes and four extendable injection needles and a handle is used for injecting the gel in four different locations around the urethra.  
         [0007]     A drawback with the injecting device is that it contains no means for facilitating the positioning of the injection needles. An exact positioning of the needles improves the possibilities of a successful treatment.  
       THE INVENTION IN SUMMARY  
       [0008]     It is an objective of the invention to overcome the above-mentioned drawback and to provide a device and a method that will ensure the reliable positioning and delivering of a bulking agent.  
         [0009]     A device in accordance with the invention comprises a treatment catheter that is inserted through the urethra until a tip extends into the bladder. At the tip, the treatment catheter includes a balloon that can be inflated to a size sufficiently large to prevent it from being withdrawn from the bladder and moved through the urethra when in an inflated state. The treatment catheter has a length sufficient to reach the bladder from a position outside the body of the patient.  
         [0010]     A hollow needle is provided in the catheter and can be extended radially from an opening or outlet in the catheter. The needle or an extension thereof, extends from a treatment position in the urethra to a position outside the body of the patient, where the bulking agent can be supplied to the needle. The needle is hollow to conduct the bulking agent to the tip, which is sharp to penetrate the tissue of the urethra. The needle has one or a plurality of openings for delivering the bulking agent or otherwise administering drugs.  
         [0011]     In performing the treatment, the catheter is inserted in the urethra until the tip of the catheter is within the bladder, and the balloon is inflated. Then the catheter is retracted, to position the balloon against the bladder neck which surrounds the urethra where it opens into the bladder. As a result, the position of the catheter within the urethra and the outlet from which the needle is extended are well determined, preferably at a location along the length of the urethra from the bladder neck at which the injection of the bulking agent will have a desired effect. As a result, the needle can be extended at the intended position and the bulking agent can be delivered through the needle at the intended location.  
         [0012]     The treatment catheter preferably possesses a high torsional stiffness to make it possible to rotate the catheter and insert the needle at different angles, all of which are located at the desired and intended position established by the balloon resting against the bladder neck.  
         [0013]     The treatment catheter for female patients can be substantially shorter than the treatment catheter for male patients, due to the shorter urethra of women. The distance between the balloon and the needle outlet also varies depending on the sex of the patient. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]     The invention will now be described in more detail with the aid of exemplary embodiments and with reference to the accompanying drawings, in which  
         [0015]      FIG. 1  is a side view partially in section of a first embodiment in accordance with the invention of a catheter for female patients;  
         [0016]      FIG. 2  is a sectional view of an end of the catheter shown in  FIG. 1  with connections for conducting liquid and the bulking agent within the catheter from outside of the patient;  
         [0017]      FIG. 3  is a side view partially in section of a second embodiment in accordance with the invention of a catheter for male patients;  
         [0018]      FIG. 4  is a side view of a female urethra and bladder after treatment in accordance with the invention;  
         [0019]      FIG. 5  is a sectional view taken at line V-V shown in  FIG. 1 ; and  
         [0020]      FIG. 6  is longitudinal sectional view of a section of the treatment catheter shown in  FIG. 1  adjacent to a tip end of the catheter. 
     
    
     DETAILED DESCRIPTION  
       [0021]     A treatment catheter  10  for women patients is shown in  FIG. 1  in a treatment position within the urethra  13 . A tip  11  at a first end of the catheter  10  extends into the bladder  12 , and an opposite second end of the catheter is located outside the body of the patient (not shown). It should be noted that only a part of the bladder  12  is shown. An inflatable balloon  14  or anchor is close to the tip  11  on a section of the catheter  10  located within the bladder  12 .  
         [0022]     As shown in  FIG. 1 , the balloon  14  is inflated to a size sufficiently large to prevent unintentional withdrawal of the catheter  10  through the urethra  13 . The size and location of the balloon  14  also ensures a predetermined axial or longitudinal position of the treatment catheter within the urethra  13 , as will be further described below. Exerting a small pulling force on the catheter  10  from outside of the patient when the balloon  14  is inflated can further ensure the predetermined position of the catheter within the urethra. A first lumen  15  extends lengthwise through the catheter and has a first opening  16  into the balloon  14 . The first lumen  15  is used to inflate the balloon with a suitable material, such as water, salt-solution or air.  
         [0023]     An optional second opening  17  of an optional second lumen  18  is located at the tip. The second lumen  18  extends lengthwise inside the catheter  10  between the first and second ends of the catheter. The lumen  18  and its opening  17  can be used to drain urine from the bladder in connection with the treatment, or to otherwise communicate between the interior of the bladder and the second end of the catheter  10  outside of the patient.  
         [0024]     A third lumen  19  in the catheter extends from the second end of the catheter to an opening or outlet located at a predetermined distance from the inflatable balloon  14 . At the outlet of the lumen  19 , the outer wall of the catheter has a hole or a membrane or a section that can be penetrated by advancing a needle  20  through the lumen  19  and out of the outlet. The portion of the third lumen  19  adjacent to the outlet has a sloping section  21 , shown in  FIG. 6 , which directs the needle  20  at a predetermined angle out of the catheter when a pushing force is exerted on the needle from outside of the patient at the second end of the catheter. The third lumen  19  constitutes a guide for the needle and can be replaced by or complemented with a tube having a bent end section at the outlet. The bent end or sloping section  21  is sufficiently strong to deflect the needle  20  into the urethra  13  at the desired angle upon advancement of the elongated needle out of the outlet of the lumen  19 .  
         [0025]     The needle  20  or an extension thereof extends from the second outside end of the catheter to the outlet of the lumen  19  which is spaced from the balloon  14 . The needle  20  has a pointed end which is sufficiently sharp to penetrate the tissue surrounding the urethra  13 . At the second outside end of the catheter  10 , the needle  20  is connected to a supply device  22  for delivering the bulking agent or gel through the hollow needle. The supply device  22  can comprise a conventional syringe or any similar device. The needle  20  is arranged with its pointed end inside the catheter  10  and the lumen  19  during insertion of the catheter  10  in the urethra  13 .  
         [0026]     Shown schematically in  FIG. 2  is a dual port Y-connector  23  used for connecting the bulking agent supply device  22  to the needle  20  and for connecting a similar supply device  26  for supplying an appropriate inflation fluid through the lumen  15  to the balloon  14  to the catheter  10 . A central hollow space  24  in the Y-connector  23  can be used for draining urine from the bladder through the lumen  18 . The bulking agent supply device  22  is connected to a first port  25  of the connector  23 , and the inflation supply device  26 , such as a syringe, is connected to a second port  27  of the connector  23 . An outer or rear end of the needle  20 , or an extension part thereof, is moved in and out of the first port  25  to extend and withdraw, respectively, the forward sharp end of the needle  20  from the opening position of the lumen  19  at the catheter wall.  
         [0027]      FIG. 3  shows a treatment catheter  10 ′ for male patients. The treatment catheter  10 ′ comprises the same elements as the female catheter  10  ( FIG. 1 ). A tip  11  at the forward end of the catheter  10 ′ is formed to facilitate the insertion of the catheter  10 ′ through the male urethra  13 ′, which is substantially longer for male patients than the female urethra  13  ( FIG. 1 ) is for female patients. The inflatable balloon  14  is provided near the tip  11  of the catheter  10 ′, and the first lumen  15  is arranged in connection with the balloon  14  for inflating it. The optional second lumen  18  with the optional second opening  17  at the tip of the catheter  10 ′ can be used for draining the bladder  12 . In the third lumen  19 , the needle  20  is moved axially or longitudinally, so as to be entirely within the lumen  19  of the catheter  10 ′ or extended outward from the outlet of the lumen  19  of the catheter  10 ′ into the tissue surrounding the urethra  13 ′ for injecting the bulking agent during the treatment process. The treatment catheter  10 ′ is flexible and pliable in order to be introduced flexibly through the urethra  13 ′ to the treatment position in a male patient.  
         [0028]     A comparison of  FIGS. 1 and 3  makes it apparent that the distance between the balloon  14  and the outlet of the lumen  19  where the needle  20  is extended from the catheter wall is larger in the catheter  10 ′ for male patients than in the catheter  10  for female patients. The reason for the difference in the distance between the balloon in the outlet of the lumen  19  is that for male patients a prostate gland  28  ( FIG. 3 ) is located distally of the bladder  12  and the tissue for treatment in male patients is located distally of the prostate gland  28 .  
         [0029]     The relative terms “proximal” and “distal” are used in this description in relation to the patient and his or her urethra  13 ′ or  13 , respectively. The portions of the urethra  13 ′ or  13  adjacent to the bladder  12  are more closely located to the central core of the patient and are therefore regarded as occupying “proximal” positions relative to the patient. The portions of the urethra  13 ′ and  13  which are located near the exterior opening of the urethra on the outside of the patient are more remotely located from the central core of the patient and are therefore regarded as occupying “distal” positions relative to the patient. Accordingly, the portions of the patient&#39;s anatomy which are the most internal within the patient are referred to as “proximal,” and the portions of the anatomy which are the most external of the patient are referred to as “distal.” The distal portions of the urethra are therefore downstream relative to the normal direction of urine flow through the urethra, and the proximal portions of the urethra are therefore upstream relative to the normal direction of urine flow through the urethra.  
         [0030]     In a treatment process the catheter tip  11  is inserted in the urethra of the patient until the tip  11  reaches a location where it is positioned in the bladder  12 . The balloon  14  is inflated within the bladder  12 , and the bladder is optionally drained through the second lumen  18 . By exerting a pulling force on the second end of the catheter when the balloon  12  is inflated, the inflated balloon  12  will contact the bladder neck and the catheter will be positioned in a predetermined axial or longitudinal location in the urethra relative to the bladder neck. Once in this position, the needle  20  is extended from the outlet of the lumen  19  by pushing the needle  20 , or an extension thereof, at the second end of the catheter.  
         [0031]     The sharpened forward tip end of the needle  20  will penetrate the mucous membrane of the urethra and the surrounding tissue, and the tip of the needle  20  will be positioned for delivering the bulking agent at a radial distance from the catheter. Normally, the radial distance is 3-10 mm, and normally approximately 10 mm. After administering the appropriate amount of the bulking agent at one injection position, the tip end of the needle  20  is pulled back into the lumen  19 , and the complete catheter is rotated through an angular interval of approximately 90° around its longitudinal axis. The needle is extended into the tissue in a second position which is angularly rotationally displaced from the previous location where the bulking agent was injected. The bulking agent is then delivered at this second position which is rotationally angularly displaced from the previous location. The catheter should also have a torsional stiffness characteristic to assure that the rotational angle or interval for extending the needle can be directly controlled by rotating the second end of the catheter from outside the body.  
         [0032]     Preferably, the steps of extending the needle, injecting the bulking agent, withdrawing the needle and rotating the catheter in another rotational interval are repeated, in two further steps (four total rotationally displaced injection positions) when the catheter is rotated 90° in each rotational interval between the adjacent angularly rotationally displaced injection portions, thus ending up with bulking agent injected in four different angularly displaced positions which circumscribe the urethra in an annular manner. Of course, the amount of the rotational interval may be adjusted as desired or necessary to inject the amount of bulking agent circumscribing the urethra as required to achieve an effective treatment for urinary incontinence. It is also possible to provide two diametrically opposite positioned lumens  19 , each with its own needle  20 , within a single catheter  10  or  10 ′, or a plurality of distributed lumens  19  for needles  20 , and in so doing enable simultaneous injection of the bulking agent at two or more positions circumscribing the urethra. After completing the treatment, the first lumen  15  is used to empty the balloon  14  to allow the treatment catheter to be removed.  
         [0033]     The balloon  14  fullfills an important function in regard to injecting the bulking agent. The inflated balloon  14  will locate or anchor the catheter in a predetermined location within the urethra by maintaining the first end of the catheter in a fixed position in the bladder as a result of the inflated balloon  14  contacting the bladder neck. By pulling the catheter at the second end, as will be done preferably in advance of each injection of the bulking agent, the catheter will be positioned in the urethra so that the balloon will contact the bladder neck. As a result and because the lumen  19  is retained in a fixed position within the catheter, the outlet of the lumen  19  from which the needle protrudes out of the catheter is also very well determined. Consequently, each separate injection of the bulking agent is located at approximately the same distance distal of the bladder neck. The outlet of the lumen  19  from which the needle protrudes out of the catheter is normally is 2-40 mm behind the balloon for female patients and is normally 5-100 mm behind the balloon for male patients. It is appropriate to provide different catheters with predetermined sizes and different needle extension positions to fit different physical conditions.  
         [0034]      FIG. 4  illustrates the state of the tissue surrounding urethra after the bulking agent has been injected during the treatment. In four (two are shown) different locations, and in other locations when a rotational interval other than 90° is used, a circumferential sphere  29  of bulking agent has been placed distally of the bladder  12 . The spheres  29  form an annular ring of bulking agent in the tissue which circumscribes the urethra at a position distal of a sphincter muscle at the bladder neck of a female patient ( FIG. 1 ), and circumscribes the urethra at a position distal of an external sphincter muscle distal of the prostate gland  28  of a male patient ( FIG. 3 ). Each separate injection of the bulking agent which forms a sphere  29 , and all of the spheres  29  are located at approximately the same longitudinal location along the urethra, as a result of the positioning established by the balloon  14  contacting the bladder neck in the bladder  12 . Locating the separate spheres  29  of injected bulking agent at approximately the same longitudinal location causes injections of bulking agent to cooperate better with one another in forming the annular ring of spheres  29 , and a better formed annular ring of spheres  29  results in providing additional support and lift for the sphincter muscle to avoid and reduce urinary incontinence problems.  
         [0035]      FIG. 5  illustrates, in a cross sectional view of one embodiment of a treatment catheter in accordance with the invention, how the lumens  15 ,  18  and  19  can be arranged in the catheter. The first lumen  15  extends in a wall  30  of the catheter and is used for inflating the balloon  14 . The second lumen  18  runs axially along the catheter in a central position, circumscribed by the wall  30 . When the catheter is in the treatment position, the second lumen  18  may be used to drain the bladder. Finally, the third lumen  19  extends in the wall  30  of the catheter opposite from the first lumen  15  and functions as a support or guide for the needle  20 .  
         [0036]     In the embodiment shown in  FIG. 5 , the exterior surface of the wall  30  of the catheter has a circular cross section while exterior surface of the second lumen  18  has an oval cross section. Other cross sections, such as an oval cross section of the catheter and a circular cross section of the second lumen, can be used. It is important that the rotational position of the catheter can be determined, because the catheter is rotated through different angular intervals into different positions during treatment, as described above. In the embodiment shown in  FIG. 5 , a projection or rib  31  is provided on the outer surface of the catheter along at least a section of the catheter for use in determining the rotational position of the catheter. It is possible also to use a color marking or a longitudinal indentation for this purpose. The needle  20  is also hollow, as shown in  FIG. 5 . The hollow interior opening of the needle conducts the bulking agent from the supply device  22  ( FIG. 2 ) to and out of openings in the sharpened tip end of the needle  20 .  
         [0037]      FIG. 6  also illustrates an example of the location of the lumens  15 ,  18  and  19  within the catheter  10 . The first lumen  15  runs along a bottom part (as shown) of the catheter and the second lumen  18  runs in a central part thereof. The dimensions of the lumens may vary. The third lumen  19  runs in parallel with the first lumen  15  and the second lumen  18 , but the third lumen  19  ends at the forward outlet with an angled or sloping section  21 . When the needle  20  is pushed inwards or forward in the third lumen  19 , the forward portion of the needle  20  will be deflected at an angle “a” determined by the sloping section  21 . The angle “a” can be from 10° to 90°. Preferably the angle “a” is approximately 30°.  
         [0038]     In the manner described above, the injections of the bulking agent at reliably located positions circumscribing the urethra measured relative to the bladder neck results in the bulking agent creating a more complete and better positioned annular ring surrounding the urethra. The ability to inject the bulking agent at reliable and predetermined positions measured relative to the bladder neck is achieved by the use of the balloon on the catheter, and consistently positioning the balloon in contact with the bladder neck prior to each injection. Providing sufficient torsional stiffness of the catheter allows the catheter to be rotated at desired and controllable rotational intervals to distribute each of the bulking agent injections at desired and more precise circumferential positions surrounding the urethra, thereby establishing better effects created by the bulking agent in the continuous annular ring surrounding the urethra. The annular ring of bulking agent resulting from this treatment is better formed and is more effective in supporting the sphincter muscle, thereby enhancing the effectiveness of the sphincter muscle to reduce or eliminate urinary incontinence problems. Many other advantages and improvements will be apparent upon gaining a more complete appreciation for the invention.  
         [0039]     Presently preferred embodiments of the invention and many of its improvements have been described with a degree of particularity. This description is of preferred examples of implementing the invention, and is not necessarily intended to limit the scope of the invention. The scope of the invention is defined by the following claims.