WO1997036631A1

WO1997036631A1 - Urinary catheter having elongating balloon

Info

Publication number: WO1997036631A1
Application number: PCT/US1997/004613
Authority: WO
Inventors: James E. Shapland; Keith R. Hildebrand; James S. Sharrow
Original assignee: Iotek Incorporation
Priority date: 1996-03-29
Filing date: 1997-03-21
Publication date: 1997-10-09

Abstract

The present invention is directly related to an apparatus for delivering fluid into a patient's urethra. The patient has a bladder. The apparatus comprises a catheter having a proximal portion and a distal portion. A first balloon is operably connected to the catheter. A second balloon is operably connected to the distal portion of the catheter. The second balloon has an inflated state and a deflated state. The second balloon is configured to have an inflated portion that forms and elongates as the second balloon changes from the deflated state to the inflated state. Another embodiment of the present invention is directed to a method of delivering an agent to a prostate gland of the patient. The patient has a urethra and a bladder. The method utilizes a catheter that has a distal portion, a first balloon operably connected to the catheter, a second balloon operaby connected to the distal portion, and an intermediate portion between the first and second balloons. The method is performed by inserting the catheter through the urethra so that a second balloon is positioned within the bladder. The first balloon is inflated. The second balloon is inflated, which provides axial tension along the intermediate portion of the catheter, seeks the second balloon at the neck of the bladder, and substantially isolates the bladder from the urethra.

Description

URINARY CATHETER HAVING ELONGATING BALLOON

Technical Field The present invention relates to a catheter for the treatment of a prostate gland, and more specifically to a catheter that has an elongating balloon and a method of use.

Background

Many techniques exist for delivering drugs or other medicaments to body tissue. These techniques include oral administration; injection directly into body tissue, such as through an intramuscular injection; topical or transcutaneous administration where the drug is passively absorbed into, or caused to pass across, the skin or other surface tissue; and intravenous administration, which involves introducing a selected drug directly into the blood stream. Except for topical or transcutaneous administration, the above drug delivery systems tend to be systemic. In other words, administration of the drug is delivered throughout the body by the blood stream. Transcutaneous drug delivery systems deliver a drug locally to a selected area, and are limited to external application of a drug through the patient's skin or other surface tissue. Thus, the above described drug delivery systems generally are not appropriate for the localized treatment of internal body tissue.

Although many medical situations are satisfactorily treated by the general systemic administration of a drug, there are many treatments that are facilitated and/or improved by the ability to deliver or administer a drug locally to a selected portion of internal body tissue, without appreciably affecting the surrounding tissue. One example is the prostate gland, which is subject to various diseases such as prostatitis, benign prostatic hyperplasia, and prostate cancer. The urethra allows relatively easy access to the prostate from outside the patient by means of a catheter.

The urethra includes the prostatic urethra and the membranous urethra. All of the major ducts of the prostate gland open on the surface of the prostatic urethra. These ducts extend into the prostate and branch into ductules (smaller ducts) and eventually end in acini (rounded sacs). The outside of the prostate gland is surrounded by a tough fibrous capsule that serves as a substantial physical barrier between the spongy prostatic tissue and the rest of the peritoneal environment. By using an appropriately designed catheter that is introduced through the urethra, it is possible to access the prostate via the prostatic ducts that extend deep into the gland.

There are prior devices for delivering drugs to tissue to the prostate gland via the prostatic urethra and the prostatic ducts. Such devices include catheters that have drug-delivery bladders made from a porous membrane. The drug-delivery balloon is placed into the prostatic urethra and inflated with a drug in a fluid form. The drug is pressurized so that it is caused to pass through the porous or perforated membrane and transported into the prostatic ducts. There is a significant problem that results from delivering the drug through this type of membranous balloon. Specifically, the transport of the drug into the prostate gland is impeded and thus much less efficient.

One impediment is that the pressurized balloon expands and exerts a force against the walls of the prostatic urethra. This force compresses the prostatic tissue and causes the ducts to restrict and block the flow of the drug into the prostate gland. As a result, the drug typically does not distribute evenly throughout the ducts, nor throughout the prostate gland. Compression of the prostatic ducts also prevents or slows the flow of the drug solution into the interior of the prostate gland.

Another impediment is the porous membrane through which the drug solution must pass before it enters the prostatic ducts. Such an impediment slows the flow of the drug solution and results in additional inefficiency. Slowing the flow of the drug solution results in longer delivery times and most likely lower levels of drug in the prostate gland. Additionally, a longer administration period requires additional time from the caregiver. This expense is passed on to the patient, thereby increasing the cost of treatment.

Therefore, there is a need for a catheter that is capable of delivering drugs and diagnostic fluids to the prostate gland via the prostatic urethra and prostatic ducts, wherein the catheter does not compromise flow through the prostatic ducts by exerting pressure against the walls of the prostatic urethra. There are also catheters that include multiple occlusion balloons. However, these catheters rely only on inflation pressure within the balloons in order to create a seal between the balloon and the wall of a passageway, such as an artery. Such devices have a significant problem because the balloon pressure alone may not be adequate to prevent a fluid from seeping between the balloon and the passageway wall during high pressure delivery that is required to drive a fluid into a prostate gland. Therefore, there is also a need for a catheter that is capable of enhancing the sealing effect of occlusion balloons on a catheter.

Summary The present invention provides a catheter for treating the prostate gland which isolates the prostatic urethra from the membranous urethra and the bladder so that fluid may be transported into the prostatic ducts without compromising flow through the openings to the prostatic ducts and without substantial leakage of the fluid out of the prostatic urethra.

The present invention is directly related to an apparatus for delivering fluid into a patient's urethra. The patient has a bladder. The apparatus comprises a catheter having a proximal portion and a distal portion. A first balloon is operably connected to the catheter. A second balloon is operably connected to the distal portion of the catheter. The second balloon has an inflated state and a deflated state. The second balloon is configured to have an inflated portion that forms and elongates as the second balloon changes from the deflated state to the inflated state. Another embodiment of the present invention is directed to a method of delivering an agent to a prostate gland of a patient. The patient has a urethra and a bladder. The method utilizes a catheter that has a distal portion, a first balloon operably connected to the catheter, a second balloon operably connected to the distal portion, and an intermediate portion between the first and second balloons. The method is performed by inserting the catheter through the urethra so that a second balloon is positioned within the bladder. The first balloon is inflated. The second balloon is inflated, which provides axial tension along the intermediate portion of the catheter, seals the second balloon at the neck of the bladder, and substantially isolates the bladder from the urethra.

Description of the Drawings Figure 1 is a view in partial view of a catheter embodying the present invention, the catheter being located in a delivery position within the male urethra and bladder. Figure 2 is an enlarged cross-sectional view of the catheter illustrated in Figure

1 taken along line 2-2.

Figure 3 A is a partial view of the catheter illustrated in Figure 1 showing a distal portion inflated to form an inflated portion.

Figure 3B is a partial view of the catheter illustrated in Figure 3 A showing the inflated portion elongating toward a proximal portion of the elongating balloon. Figure 3C is a partial view of the catheter illustrated in Figures 3A and 3B showing the inflated portion pressing against the bladder wall.

Figure 4 is a partial cross-sectional view of an alternative embodiment illustrated in Figure 1 having an electrode and a sheath.

Detailed Description

The present invention will be initially described in general terms. A preferred embodiment of the present invention then will be described in detail with reference to the drawings, wherein like reference numerals represent like-parts and assemblies throughout the several views. Reference to the preferred embodiment does not limit the scope of the invention, which is limited only by the scope of the claims attached hereto. The present invention comprises a catheter with two balloons for isolating a target area for treatment. The catheter is capable of delivering fluid to the target area of the passageway that is isolated between the balloons. Additionally, an axial tension is created between the balloons, which enhances their ability to create a seal. The present invention can be used to deliver fluid to the prostate gland and is advantageous in that the prostatic ducts remain substantially open, even when the balloons are inflated. Another advantage is that the axial tension enhances the sealing effect of the balloons.

Figures 1 and 2 illustrate one preferred embodiment of a catheter according to the present invention, generally shown as 20, for isolating and treating a prostate gland 10 of a patient. The patient has a bladder 12, bladder neck 14, and a urethra 15. The urethra 15 includes a prostatic urethra 16, membranous urethra 18, bulbous urethra 19, and pendulous urethra (not shown).

Catheter 20 has a catheter body 22 that includes a distal portion 24 and a proximal portion 26. Elongating balloon 28, shown in an inflated state, is affixed to distal portion 24 of catheter body 22 such that catheter body 22 passes through elongating balloon 28 and elongating balloon 28 is sealed to catheter body 22. A proximal occlusion balloon 30 is affixed to catheter body 22 in a manner similar to elongating balloon 28.

The proximal occlusion balloon 30 is positioned a distance from the elongating balloon 28, such that the proximal occlusion balloon 30 can be positioned in the bulbous urethra 19 when the elongating balloon 28 is seated at the bladder neck 14. In this configuration the distance between the proximal occlusion balloon 30 and elongating balloon 28 is about equal to the combined length of the average prostatic urethra 16 and the average membranous urethra 18. The distance can be between about 3 cm and about 7 cm. Using this configuration is advantageous when anesthetizing a patient prior to prostatic surgery. The anesthesia helps to numb the nerves at the membranous urethra 18, which can become irritated during prostatic surgery.

In an alternative embodiment, the distance between the proximal occlusion balloon 30 and the elongating balloon 28 is approximately the same length as or slightly longer than the average prostatic urethra 16. Thus, proximal occlusion balloon 30 and the elongating balloon 28 isolate substantially all of the prostatic urethra 16 from substantially all of the membranous urethra 18 and substantially all of the bladder 12. In this configuration, proximal occlusion balloon 30 and elongating balloon 28 are spaced far enough apart so that the balloons 30 and 28 exert minimal pressure against the wall of the prostatic urethra 16. Thus, a minimal number of prostatic ducts are caused to collapse when catheter 20 is in the delivery position. In this embodiment, the distance between the proximal occlusion balloons 30 and elongating balloon 28 is in the range from about 3 cm to about 6 cm. This configuration is advantageous when delivering toxic or otherwise dangerous agents that can cause side effects or otherwise damage tissue if exposed to tissue other than the prostate gland 10.

Figure 2 illustrates a cross-section of the catheter and the elongating balloon 28, which can be used as a combined distal occlusion balloon and positioning balloon. The elongating balloon 28, shown in a deflated state, has a distal portion 32 and a proximal portion 34. The elongating balloon 28 also defines an inner diameter. The outer diameter of distal portion 32 is less than the outer diameter of proximal portion 34. The inner diameter is substantially uniform. The elongating balloon 28 can be made from material such as latex, polyurethane, or silicon.

Catheter body 22 includes 4 lumens: drainage lumen 36, first inflation lumen 38, second inflation lumen 40, and delivery lumen 42. Drainage lumen 36 extends from a distal tip 44 of the catheter body 22 to the proximal portion 26. As described in more detail below, drainage lumen 36 drains urine from the bladder 12 when the catheter 20 is inserted into the urethra 15.

First inflation lumen 38 extends from the proximal portion 26 to a position proximate the elongating balloon 28. First inflation port 46 passes from first inflation lumen 38 to the interior of elongating balloon 28 so that elongating balloon 28 can be inflated by injecting a fluid through first inflation lumen 38. Second inflation lumen 40 extends from the proximal portion 26 of the catheter body 22 to a position proximate proximal occlusion balloon 30. Second inflation port 48 passes from second inflation lumen 40 into the interior of proximal occlusion balloon 30.

Delivery lumen 42 extends from the proximal portion 26 of the catheter body 22 to a position proximate the gap between elongating balloon 28 and proximal occlusion balloon 30. Delivery ports 50 pass from delivery lumen 42 to the outer surface of catheter body 22. Catheter body 22 may define as many as 20 delivery ports 50, which are macroscopic in size. Preferably, there are three or four delivery ports 50. The size of the delivery ports 50 is preferably in the range from about 1 mm to about 2 mm. The most preferred size for the delivery ports 50 is 1 mm. The procedure for using catheter 20 is as follows. Catheter 20 is inserted into the urethra 15 using lubrication, sterile techniques, and any other technique that is commonly used to insert a Foley-type urological catheter. Catheter 20 is inserted into the urethra 15 until elongating balloon 28 enters the bladder 12 and is preferably inserted while there is urine within the bladder 12. Having urine within the bladder 12 is useful because the caregiver that inserts catheter 20 will know that positioning balloon 28 has entered the bladder 12 when urine is observed in drainage lumen 36 or when urine can be aspirated through drainage lumen 36. At this point the proximal occlusion balloon 30 should be positioned in the bulbous urethra 19.

Figures 3 A, 3B and 3C, show elongated balloon 28 mounted on a catheter body 22 and positioned so that the end 52 of the proximal portion 34 is located within the bladder neck 14. One skilled in the art will realize that the end of the proximal portion 34 can also extend into the distal portion of the prostatic urethra 16. Such positioning will not affect delivery of a fluid into the prostate gland 10 because a majority of the prostatic ducts open to the proximal three quarters of the prostatic urethra 16.

Once elongating balloon 28 is inserted within the bladder 12, fluid is injected through the second inflation lumen 38 until the proximal occlusion balloon 30 is inflated to a diameter of about 1 cm to about 5 cm. A predetermined, fixed volume of fluid is preferably used in order to prevent over inflation and bursting of the proximal occlusion balloon 30. The fluid can be air, water, or saline, etc. However, the preferable fluid is sterile water.

After proximal occlusion balloon 30 is inflated, a fluid is injected through the first inflation lumen in order to inflate the elongating balloon 28. As shown in Figure 3 A, the distal portion 32 is the first portion of the elongated balloon 28 that expands thereby forming an inflated portion 54. As additional fluid is injected to the elongating balloon 28, the length of the inflated portion 54 will increase, as shown in Figure 3B, until the inflated portion 54 presses against the wall of the bladder 12, as shown in Figure 3C.

As the elongating balloon 28 continues to inflate, it will continue to exert force against the wall of the bladder 12 and urge the catheter body 22 toward the bladder 12 until the proximal occlusion balloon 30 becomes seated against the wall of the bulbous urethra 19. This action will also generate axial tension along the catheter body 22 between the proximal occlusion balloon 30 and the elongating balloon 28. The axial tension will enhance the seal of the proximal occlusion balloon 30 and the elongating balloon 28. Fluid can be delivered to the prostate gland 10 when the catheter 20 is in this delivery position.

Again, a predetermined amount of fluid is used to inflate the elongating balloon 28, which will protect against over inflating the elongated balloon 28.

Additionally, any type of fluid can be used to inflate the elongating balloon 28 such as air, water, saline, or sterile water. If the proximal occlusion balloon 30 is positioned so that it will be located in the membranous urethra 18, the caregiver should anchor the proximal portion 26 of the catheter body 22 so that it does not slip while the elongating balloon 28 is inflated. The catheter body 22 can be anchored by taping or clamping the proximal portion 26 of the catheter body 22 to the patient's body. Once the proximal portion 26 is anchored, the caregiver can inflate the proximal occlusion balloon 30 and the elongating balloon 28. This method also permits the generation of axial tension, which enhances the sealing affect of the elongating balloon.

Drugs or diagnostic fluids may be delivered to the prostate gland 10 after catheter 20 is in the delivery position and the balloons 28 and 30 are inflated. One skilled in the art will realize that a pressure gauge and syringe can be placed in fluid communication with the delivery lumen 42 to deliver the drug or diagnostic fluid to the prostatic urethra 16. Any number of types of syringes may be used such as a standard syringe, an adjustable syringe, or a syringe pump. However, an adjustable syringe is preferably used. An adjustable syringe is one that has threads or some other type of self-locking mechanism.

Once delivered, the drug or diagnostic fluid is pressurized, thereby transporting it into the ducts, ductules, and acini. The pressure on the fluid may range between about 0.1 psi and about 10 psi. However, the preferable pressure is between about 0.1 psi and about 6 psi. The most preferred range of pressure is between about 0.1 psi and about 3 psi. This pressure causes the fluid to fill the prostatic ducts, ductules, and acini.

Preferably, a constant pressure should be maintained over a period of time ranging from about 0.25 hours to about 4 hours. The preferred range of time is between about 0.25 hours to about 2 hours, and the most preferred range is between about 0.25 hours and about 0.5 hours. One skilled in the art will realize that the precise amount of time will vary depending on the drug or the diagnostic agent being employed.

Maintaining constant pressure over a period of time, rather than a simple administration of a fixed volume of drug solution, will more likely result in homogeneous prostatic tissue concentrations. If accurate drug dosing is not required, a fixed volume of solution can be simply administrated. An example of when a fixed volume of solution is appropriate is when a positive contrast agent is introduced into the prostate gland 10. The preferable procedure for withdrawing catheter 20 from the urethra 15 depends on whether toxic or caustic agents were delivered. For nontoxic drugs and diagnostic fluids such as antibiotics, anti-inflammatories, positive contrast agents, etc., the pressure of the fluid is simply reduced to zero, the elongating and the proximal occlusion balloons 28 and 30 are deflated, and the catheter 20 is removed from the urethra 15.

If toxic or caustic agents were delivered, an alternative procedure for withdrawing catheter 20 is preferred. More specifically, a slight negative pressure is applied to the fluid in order to remove the excess drug or diagnostic agent from the prostatic urethra 16 after the administration period is complete. The prostatic urethra 16 may then be flushed with a saline solution. The saline solution is added and removed via delivery lumen 42 in the same fashion the drug or diagnostic fluid was initially delivered to the prostatic urethra 16. After the saline solution is removed, the elongating and proximal occlusion balloons 28 and 30 are deflated and the catheter 20 is removed.

In yet another alternative embodiment, the catheter 20 may have a telescoping body (not shown) in which the proximal occlusion balloon 30 is attached to a tubular, outer portion and the elongating balloon 28 is attached to an extendable, inner portion. A hemostatic-type adjustable seal can be used to secure the extendable portion relative to the tubular portion. Such a telescoping catheter body is described in commonly- assigned United States Patent 5,419,763, the disclosure of which is hereby incorporated by reference.

An advantage of a telescoping catheter body is that the distance between the proximal occlusion balloon 30 and the elongating balloon 28 can be adjusted to the length of the patient's urethra 15. Additionally, the relative position of the proximal occlusion balloon 30 can be adjusted so that it is positioned in either the membranous urethra 18 or the bulbous urethra 19 when the catheter 20 is in the delivery position. Additionally, the catheter 20 can utilize iontophoresis, electroporation, and/or phonophoresis to assist the transportation of the agent into the prostatic ducts. These non-pressure means of transportation also enhance drug penetration across the prostatic epithelium and into prostatic tissue. These methods may also increase cellular penetration of certain agents. Examples of these agents include DNA, RNA, etc. These non-pressure means of transportation may also make penetration into prostatic calculi possible. Iontophoresis, electroporation, and phonophoresis are discussed in more detail in United States Patent 5,419,763, the disclosure of which was incorporated by reference above. Additional information on iontophoresis can be found in United States Patent 5,286,254, the disclosure of which is hereby incorporated by reference. Figure 4 illustrates alternative embodiments in addition to those described in

United States Patent 5,419,763. For example, the catheter 20 can include a sheath 56 that covers an electrode 58 and delivery ports 50. The sheath 56 can be tubular and fixed to the catheter body 22 with adhesive 60. The sheath 56 can be formed from a polymer matrix that absorbs fluid that passes through the delivery ports 50. Alternatively, the sheath 56 can be formed from a porous membrane. The pores can be either microporous (0.2-100 micron) or macroporous (100 micron- 1 millimeter) depending on the density of the pores and manufacturing process. Specific materials that can be used to form the sheath 74 include PTFE Teflon; woven polymer filaments such as nylon, LDPE, polyurethane, or Kevlar; braided polymers; and extruded or perforated polymeric or elastic tubing.

The catheter body 22 can include a portion 62 that has a narrowed diameter, thereby defining a recess 64. The electrode 58 is positioned within the recess 64. The sheath 56 extends over the recess 64 and forms a delivery chamber 66 that is in fluid communication with delivery ports 50. In use, the fluid fills delivery chamber 84 and is either absorbed in sheath 56 or passes through the pores defined in sheath 56, thereby forming a path between the electrode 58 and the patient's body that is capable of conducting an electric current. Alternatively, the catheter body 22 has a substantially uniform diameter. In this alternative embodiment, the electrode 58 is still positioned between the proximal occlusion balloon 30 and the elongating balloon 28. Additionally, if sheath 56 is absorbent, the catheter body 22 may define only a single delivery port 50 positioned proximate to one of the sheath's 56 oppositely disposed ends 68 or 70. The sheath 56 has several advantages. For example, the sheath 52 will prevent the electrode 58 from being placed in direct contact with tissue along the urethral wall. Additionally, the sheath 56 helps to distribute the current so that mere is not a single point at which the current will pass from the electrode 58 to the tissue. As a result, hot spots are prevented, which might otherwise cause the tissue directly adjacent to the electrode 58 to burn.

While the invention has been described in conjunction with a specific embodiment thereof, it is evident that different alternatives, modifications, and variations will be apparent to those skilled in the art in view of the foregoing description. Accordingly, the invention is not limited to these embodiments or the use of elements having specific configurations and shapes as presented herein.

Claims

THE CLAIMED INVENTION IS:

1. An apparatus for treating a prostate gland of a patient, the apparatus comprising: a catheter having a proximal portion and a distal portion; a first balloon operably connected to the catheter; and a second balloon operably connected to the distal end of the catheter, the second balloon having an inflated state and a deflated state, the second balloon being configured to have an inflated portion that forms and elongates as the second balloon changes from the deflated state to the inflated state.

2. The apparatus of claim 1 wherein the second balloon is further configured to fit into the bladder when in the deflated state and the configured to substantially isolate the bladder from the urethra when in the inflated state.

3. The apparatus of claim 2 wherein the first balloon has an inflated state and a deflated state, the first balloon being configured to substantially isolate the pendulous urethra from the membranous urethra and the prostatic when in the inflated state.

4. The apparatus of claim 2 wherein the first balloon is positioned a distance from the second balloon so that the second balloon is positioned in the bulbous urethra when the second balloon is seated at the bladder neck.

5. The apparatus of claim 2 wherein the first balloon has an inflated state and a deflated state, the first balloon being configured to substantially isolate the membranous urethra from the prostatic urethra when in the inflated state.

6. The apparatus of claim 5 wherein the first balloon is positioned a distance from the second balloon so that the first balloon is positioned in the membranous urethra when the second balloon is seated at the bladder neck.

7. The apparatus of claim 1 wherein the second balloon has first and second portions, the first portion having a first outer circumference when the second balloon is in the deflated state, and the second portion having a second outer circumference when the second balloon is in the deflated state, the first outer circumference being less than the second outer circumference.

8. The apparatus of claim 7 wherein the second balloon defines an inner chamber, the inner chamber having a substantially uniform diameter when the second balloon is in the deflated state.

9. The apparatus of claim 1 wherein the catheter defines a surface, a delivery lumen, and a delivery port, the delivery port being in fluid communication with the delivery lumen and positioned between the first and second balloons, the apparatus further comprising: a first electrode operably connected to the surface of the catheter and positioned between the first and second balloons, the first electrode being connectable to a power supply; a second electrode configured to be placed against the patient's skin, the second electrode being connectable to the power supply; and a sheath covering the electrode and the delivery port, the sheath providing a conductive path so that electrical current can flow between the first and second electrodes.

10. The apparatus of claim 9 wherein the sheath is formed from a polymer matrix configured to absorb fluid through the delivery port.

11. The apparatus of claim 10 wherein the catheter defines a plurality of delivery ports, the sheath being sized and positioned to cover each of the delivery ports.

12. The apparatus of claim 9 wherein the sheath and the catheter define a fluid chamber, further wherein the sheath is formed from a porous membrane.

13. An apparatus for delivering fluid to a patient, the patient having a urethra and a bladder, the urethra having a prostatic urethra, a membranous urethra, and a bulbous urethra, the apparatus comprising: a catheter having a proximal portion and a distal portion; a first balloon operably connected to the catheter, the first balloon having inflated and deflated states, the first balloon being sized to fit within the bulbous urethra when in an inflated state; a second balloon operably connected to the distal end of the catheter, the second balloon having an inflated state and a deflated state, the second balloon being configured to have an inflated portion that forms and elongates as the second balloon changes from the deflated state to the inflated state; wherein, when the catheter is in a delivery position, the first balloon is positioned within the bulbous urethra and the second balloon is positioned at the bladder neck; and wherein, when the catheter is in the delivery position and the second balloon is in the inflated state, the inflated portion presses against the wall of the bladder and urges the catheter toward the bladder, thereby seating the first balloon against the wall of the bulbous urethra and generating axial tension between the first and second balloons.

14. A method of delivering an agent to a prostate gland of a patient having a urethra and a bladder, the method utilizing a catheter that has a distal portion, a first balloon operably connected to the catheter, a second balloon operably connected to the distal portion, and an intermediate portion between the first and second balloons, the method comprising the steps of; inserting the catheter through the urethra so that the second balloon is positioned within the bladder; inflating the first balloon; and inflating the second balloon, thereby providing axial tension along the intermediate portion of the catheter, seating the second balloon at the neck of the bladder, and substantially isolating the bladder from the urethra.

15. The method of claim 14 wherein the urethra has a bulbous urethra, the method comprising the additional step of positioning the first balloon in the bulbous urethra, further wherein the step of inflating the first balloon is performed before the step of inflating the second balloon, so that the first balloon will become anchored against the wall of the bulbous urethra upon inflation of the second balloon.

16. The method of claim 14 wherein the urethra has a membranous urethra and a prostatic urethra, the method comprising the additional steps of: positioning the first balloon within the membranous urethra so that the membranous urethra becomes substantially isolated from the prostatic urethra upon inflation of the first balloon; and anchoring the proximal catheter prior to inflation of the second balloon.

17. The method of claim 14 comprising the additional steps of delivering an agent into a portion of the urethra defined between the first and second balloons; and transporting the fluid into the prostate gland.

18. The method of claim 17 wherein the catheter defines a lumen and a port, the port being positioned between the first and second balloons and in fluid communication with the lumen, further wherein the step of delivering and agent includes the step of injecting a fluid through the lumen, and the step of transporting the fluid flows into the prostatic ducts.

19. The method of claim 17 wherein the catheter includes an electrode positioned between the first and second balloons and a second electrode is in electrical communication with the patient's body, further wherein the step of transporting the fluid includes the step of passing an electrical current between the first and second electrodes.

20. A method of delivering an agent to the prostate gland of a patient having a urethra and a bladder, the urethra including a bulbous urethra, the method utilizing a catheter that has a distal portion, a first balloon operably connected to the catheter, a second balloon operably connected to the distal portion, and an intermediate portion between the first and second balloons, the method comprising the steps of: inserting the catheter through the urethra so that the first balloon is positioned in the bulbous urethra and the second balloon is positioned in the bladder; inflating the first balloon; and inflating the second balloon after the first balloon is inflated so that: the first balloon becomes anchored against the wall of the bulbous urethra upon inflation of the second balloon; and axial tension is generated along the intermediate portion of the catheter, thereby seating the second balloon at the neck of the bladder and substantially isolating the bladder from the urethra.