Patent Application
20090078270
1. Field of the Invention
This invention relates to implantable occlusion devices and more specifically relates to implantable male contraception devices and instruments used for the delivery of such contraception devices.
2. Description of the Prior Art
Definitive male contraception is most commonly achieved by a surgical vasectomy. While the vasectomy is an effective contraception method, the procedure is very often painful and has many long term effects that are not always desirable, but are accepted as other methods of definitive contraception are not readily available.
Conventionally, a vasectomy may be performed surgically by the traditional method of removing the vas deferens completely or by cutting and sealing the vas deferens, most commonly referred to as a “keyhole” or “no-scalpel” vasectomy. Patients undergoing either type of vasectomy should consider the-procedure permanent and not reversible. In some rare cases a vasectomy may be reversed by another surgical procedure known as a vasovasostomy; however, the success rate of completely returning the reproductive capabilities of the male with this procedure is poor at best. Post-vasectomy patients are commonly limited in activities for up to four weeks and are often prone to severe and chronic pain lasting years. The vasovasostomy has been an effective means of treating pain arising from vasectomy complications, but as with most microsurgical procedures, is extremely costly. Many males desiring an effective contraception method often hesitate when considering a vasectomy due to the essentially irreversible effects of the surgery and the potential for long lasting pain.
A new method of definitive male contraception utilizing an intra vas implant has been proven to be as effective as vasectomy procedures while having significantly less complications and long term side effects. The intra vas implant (IVI) operates in a manner similar to that of an intra uterine device (IUD) in females. To achieve complete contraception capabilities in males, the IVI is surgically implanted into the vas deferens, blocking the path of sperm from the testicles to the urethra. The conventional method of surgical IVI implantation in most cases is cumbersome and time consuming.
Two common implantable devices include an injectable implant and a sutured implant.
The injectable implant utilizes an injectable polymer. The polymer in its liquid form, commonly a microcellular polyurethane or medical grade silicone rubber, is injected into the vas deferens where it hardens within twenty (20) minutes. The resulting, hard spherical plug provides a barrier to sperm. This technique was developed in China and some 300,000 men have reportedly undergone the procedure. The injectable polymer contraception method may be reversible. However, to reverse such a method a surgical removal of the plug is necessary.
The sutured implant utilizes silicone plug pairs, commonly referred to as a “Shug”. A shug is implanted into each vas deferens and anchored to the wall by small sutures. Similar to the latter method, the plug acts as a barrier to sperm. The plug is theoretically reversible although it is reportedly still being developed.
The present invention discloses a novel implantable male contraception device that may be easily introduced and removed from a patient.
It is an object of the present invention to provide an implantable device for male contraception and an implantation tool to aid in the delivery of the contraception device.
It is another object of the present invention to provide a male contraception implant that is removable.
It is yet another object of the present invention to provide a male contraception implant that may be easily inserted into the vas deferens of a patient.
It is a further object of the present invention to provide a male contraception implant that once implanted is flexible and comfortable.
It is yet a further object of the present invention to provide a male contraception implant which overcomes the inherent disadvantages of known male contraception implants.
In accordance with one form of the invention, a male contraception implant used to occlude the vas deferens of a male patient and prevent sperm travel is disclosed. The implant preferably includes an elongated tubular member having a central bore extending axially therethrough. The tubular member has basically three sections: an enlarged head portion which protrudes out of the incision in the vas deferens to aid in the removal of the implant in a reverse contraception procedure, a relatively thin tubular neck portion affixed to the head portion, and a main body portion formed of at least one widened segment, but more preferably with three widened segments, which is received by and occludes the vas deferens.
In accordance with another form of the present invention, an implantation tool to aid in the delivery of a contraception device includes a slotted ring, preferably oval or circular in shape. During the implantation procedure, an incision is made in the patient's scrotum, and the vas deferens is exposed therethrough and placed about the slot in the ring. The exposed vas deferens, held in place by the ring, is more easily accessible to the physician. A small incision is now made across the longitudinal line of the vas deferens, and a guide wire is inserted into the vas deferens. The implant, slideably mounted on the guide wire, is now placed in the vas deferens in a desired position, with the enlarged head portion of the implant exposed. The incision in the vas deferens about the protruding head of the implant is then sealed. Then, the exposed vas deferens is removed from the implantation tool and reinserted through the incision in the scrotum. The scrotum incision is then sealed.
A preferred form of the male contraception implant and implantation tool, as well as other embodiments, objects, features and advantages of this invention, will be apparent from the following detailed description of illustrative embodiments thereof, which is to be read in conjunction with the accompanying drawings.
The present invention is an implantable male contraception device 2 that may easily be introduced and, if necessary, removed from a patient, and an implantation tool 4 that aids in the delivery of the implant 2.
As shown in
The tubular member 6 of the implant 2 basically includes three sections along its axial length, each section being defined by a particular shape, or width measured radially from the longitudinal axis of the tubular member. More specifically, the tubular member includes a head portion 16 situated at or near the first axial end 8 of the tubular member 6. In the first embodiment of the present invention shown in
The tubular member 6 of the implant 2 further includes a neck portion 18 which is situated adjacent the head portion 16 along the longitudinal axis of the tubular member 6. The neck portion 18 is a flexible, relatively thin cylindrical section of the tubular member 6, having an outer diameter which is preferably less than the diameter or width of the head portion 16 and the overall width or diameter of the third section, the main body portion of the implant 2, as will be described.
The main body portion 20 of the tubular member 6 of the implant 2 is the section which is designed to occlude the vas deferens. This section is received interiorly along a portion of the vas deferens to prevent the passage of sperm therethrough. The main body portion 20 is attached to the other axial end of the neck portion 18 along the longitudinal axis of the tubular member 6. The main body portion 20 includes at least one widened segment 22, but more preferably includes a plurality of widened segments, measured from the longitudinal axis of the elongated tubular member 6 of the implant 2.
More specifically, and as can be seen from
It can also be seen from a comparison of
The second embodiment of the implant 2 shown in
With either embodiment, the first most distal widened portion segment 30 occludes the duct (i.e., vas deferens, or more generally, any anatomical vessel). However, the second widened body segment 26 will block any sperm that leak past the first segment 30. The third widened portion segment 24 of the second embodiment which is closest to the neck portion 18 provides even greater safety.
The preferred overall diameter of the implant 2 is less than about 1.2 millimeters. This size allows for even small incisions to be made in the vas deferens than conventionally, and the incision is expected to heal completely and rapidly. The enlarged head 16 of the implant 2 remains outside the vas deferens and provides a means to find the implant 2 in the event the patient wishes to reverse the contraception. The enlarged head 16, outside the vas deferens, also helps prevent migration of the implant 2 within the duct, without requiring sutures. The implant 2 is preferably constructed of medical grade silicone and may be formed by injection molding or other similar method. The use of silicone yields a flexible, comfortable implant 2 that does not induce the sensation to the patient of the presence of a foreign body.
The implant 2 may be inserted over a guide wire 14 through a small incision into the vas deferens of a patient. The main body portion 20 near the second axial end 10 of the implant 2 is inserted first, followed by the neck portion 18 near the first axial end 8. Proper placement of the implant 2 calls for the head 16 to remain outside the vas deferens. The widened segments 22 will form an interference fit with the walls of the vas deferens, thus securing the implant 2 within the vas deferens and forming a seal with the walls to prevent sperm flow past the device. The guide wire 14 may then be removed and the small incision will heal naturally. To remove the implant 2, the head 16 may be grasped by hand or instrument, and withdrawn from the vas deferens without any significant surgical intervention such as required by the conventional contraception implants and procedures.
The first embodiment of the implantation tool 4 is shown in
Preferably, the front face or rear face, or both faces, may include either one or more protrusions 42 extending outwardly therefrom, or one or more depressions, or again both protrusions and depressions provided on either or both faces. The protrusions 42 and depressions help the physician grasp the implantation tool 4 as he or she is placing the externalized vas deferens on the support 32, or inserting the guide wire 14 or positioning the implant 2 in the patient in the exposed portion of the vas deferens supported thereby.
The implantation procedure, using either embodiment of the implantation tool 4 of the present invention, will now be described. An incision is made in the patient's scrotum to expose the vas deferens. A section of the vas deferens is externalized (i.e., a portion of the vas deferens is pulled out of the scrotum through the incision) and placed around the implantation tool 4 to hold the otherwise slippery vas deferens in position. With the embodiment shown in
After a small incision is made across the longitudinal line of the vas deferens, a guide wire 14 is inserted into the vas deferens. With the help of the guide wire 14, the implant 2 device, either slideably pre-mounted on the guide wire 14 or placed on the guide wire 14 at this time, is maneuvered on the guide wire 14 into the vas deferens, with the enlarged head 16 remaining outside the semen duct (i.e., the vas deferens). After the implant 2 is properly delivered, the guide wire 14 is withdrawn. The incision in the vas deferens should heal naturally about the neck portion 18 of the implant 2 or may be sealed by the physician, leaving the enlarged head portion 16 exposed. The vas deferens is removed from the support and replaced in the scrotum. The incision in the scrotum is then sealed.
An alternative procedure would be to make a second incision in the externalized vas deferens, which second incision is spaced apart longitudinally from the first incision. The guide wire 14, with the implant 2 slidably attached thereto, is inserted into the vas deferens through the first incision, as described previously. However, instead of removing the guide wire 14 back out of the first incision after the implant 2 is properly positioned within the vas deferens, in this alterative procedure, the insertion end of the guide wire 14 is pulled through the vas deferens and out of the second incision. The implant 2, frictionally attached to the guide wire 14, is pulled into the vas deferens through the first incision. However, the enlarged head portion 16 of the implant 2 engages the outer surface of the vas deferens at the first incision and prevents the implant from following the guide wire 14 completely through the vas lumen. The engagement of the enlarged head 16 with the outer surface of the vas deferens overcomes the frictional force retaining the implant 2 to the guide wire 14 and thereby causes the implant 2 to be released from the guide wire 14 in the proper position in the vas lumen. The guide wire 14 is completely pulled through the second incision formed in the vas deferens, leaving the implant 2 behind and positioned in the vas lumen.
Since the implant 2 is preferably less than 1.2 millimeters in overall diameter, only a minor incision needs to be made in the vas deferens. Furthermore, because of the flexibility and shape of the implant 2, there is less irritation of the tissue.
The contraception device of the present invention may be implanted in an easy and gentle way. Preferably, as mentioned previously, the implant 2 is formed from a medical grade silicone. The implant 2 may be easily manufactured by injection molding.
The implantation tool 4 of the present invention preferably has a dimension of about 10 millimeters to about 20 millimeters. The tool 4 acts as a holder for the semen duct (vas deferens) and assists the physician by holding the vas deferens in position during the delivery of the implant 2.
It should be realized that the implant device 2 and implantation tool 4 of the present invention described herein are not limited to use in occluding the vas deferens. It is foreseen that the implant 2 and implantation tool 4 may be useful as not only a means for male contraception, but also may be used for occluding blood vessels and other body lumens with implants having one end protruding through the vessel wall. Other areas of application include use of the implant 2 and implantation tool 4 in the treatment of aneurisms or for the occlusion of fallopian tubes, or in the treatment of myomas.
The present invention overcomes the disadvantages inherent with the conventional designs by decreasing the complexity of implantation and the removal procedure. Utilization of the present invention provides a reversible, comfortable and definitive contraception method that can be performed by any urologist.
