Method and device for uterine fibroid treatment

Methods and devices for both imaging and treating uterine fibroid tumors in one real-time system are provided. One minimally invasive method comprises introducing a sheath into a uterus and determining a location of a fibroid using a visualization element within or on the sheath. Upon identification, a portion of the sheath is steered to position at least one treatment needle at the determined location. The needle is then anchored in uterine tissue and the fibroid treated with the needle.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to medical devices and methods. More particularly, the invention relates to methods and devices for locating and treating uterine fibroids.

There are unmet needs in the pathophysiology of the female reproductive tract, such as dysfunctional uterine bleeding and fibroids. Fibroids are benign tumors of the uterine myometria (i.e., muscle) and are the most common tumor of the female pelvis. Fibroid tumors affect up to 30% of women of childbearing age and can cause significant symptoms such as discomfort, pelvic pain, mennorhagia, pressure, anemia, compression, infertility and miscarriage. Fibroids may be located in the myometrium (i.e., intramural), adjacent to the endometrium (i.e., submucosal), or in the outer layer of the uterus (i.e., subserosal). Most commonly fibroids are a smooth muscle overgrowth that arise intramurally and can grow to be several centimeters in diameter.

Current treatment for fibroids includes medical treatment with NSAIDS, estrogen-progesterone combinations, and GnRH analogues. Pharmacologic therapy with GnRH analogues is limited due to its side effects, such as hot flashes, vaginal dryness, mood changes and bone density loss. Further, its relatively short time of treatment (e.g., 3 months) offers temporary shrinkage, wherein the fibroids usually regrow after medical discontinuation. Pharmacologic therapy is relatively ineffective and palliative rather than curative.

Hysterectomy (i.e., surgical removal of the uterus) is a common treatment for fibroids. It is performed up to 600,000 times annually in the United States. Indeed, fibroids are the indication for hysterectomy in up to one third of all cases. Hysterectomy for treating fibroids may be very effective but has many undesirable side effects such as loss of fertility, open surgery, sexual dysfunction, and long recovery time. There is also significant morbidity (e.g., sepsis, hemorrhage, peritonitis, bowel and bladder injury), mortality, and costs associated with hysterectomy treatments.

Surgical myomectomy is also an open surgical procedure requiring laparotomy and general anesthesia in which fibroids are removed. Often these procedures result in significant blood loss and can only remove a portion of the culprit tissue. In the early 1990's there was a growth in advanced operative laparoscopy techniques and laparoscopic myomectomy was pioneered. However, laparoscopic myomectomy remains technically challenging. For example, it requires laparoscopic suturing which is performed only by the most skilled of laparoscopic gynecologists. Further, prolonged anesthesia time, increased blood loss, and possibly higher risk of uterine rupture in pregnancy make laparoscopic myomectomy a challenging procedure. Currently, the removal of subserosal or intramural fibroids requires an abdominal approach.

Hysteroscopy (i.e., process by which a thin fiber optic camera is used to image inside the uterus) may include an attachment to destroy tissue. Hysteroscopic resection is a surgical technique that uses a variety of devices (e.g., loops, roller balls, bipolar electrodes) to ablate or resect uterine tissue. The uterus needs to be filled with fluid for better viewing and thus has potential side effects of fluid overload. Hysteroscopic ablation is also limited by its visualization technique and is thus only appropriate for those fibroids that are submucosal and/or protrude into the uterine cavity.

Uterine artery embolization has also been suggested as an alternative minimally invasive treatment for fibroids. Uterine artery embolization was introduced in the early 1990's and is performed by injecting small particles through a groin incision into the uterine artery to selectively block the blood supply to fibroids. Uterine artery embolization results in reduction of the myoma size from 20-70% at six months. However, side effects of this procedure include pelvic infection, premature menopause, and severe pelvic pain. In addition, long term MRI data suggest that incomplete fibroid infarction may result in regrowth of infracted fibroid tissue. Despite much interest in uterine artery embolization, the procedure rates remain low and have not grown past a few thousand performed per year in the United States. This may be due to the fact that interventional radiologists, instead of gynecologists who know how to diagnose and treat fibroid tumors, are the ones who perform uterine artery embolization procedures.

Endometrial ablation, which is primarily a procedure for dysfunctional or abnormal uterine bleeding, may be used at times for fibroids. Recently there have been many new technologies to perform endometrial ablation such as cryo energy, microwave energy, and impedance controlled radiofrequency. Endometrial ablation destroys the endometrial tissue lining the uterus, but does not specifically treat fibroids. This technique is also not suitable for women who desire to bear children. Endometrial ablation remains a successful therapy for dysfunctional uterine bleeding, but is limited in its ability to treat fibroids.

Myolysis is another alternative minimally invasive technique for fibroid treatment. Myolysis was first performed in the 1980's in Europe by using lasers to coagulate tissue, denature proteins, and necrose myometrium with laparoscopic visualization. This technique has been in use for the past several years and involves applying energy directly to the myoma. Laparoscopic myolysis can be an alternative to myomectomy, as the fibroids are coagulated and then undergo coagulative necrosis resulting in a dramatic decrease in size. Shrinkage of fibroids has been reported at 30-50%. In addition there is the obvious economic benefit of out-patient surgery, rapid recovery, and return to normal lifestyle. However, all laparoscopic techniques are limited by the fact that they can only see, and therefore only treat, subserosal fibroids.

Needle myolysis is a promising technique whereby a laparoscope is used to introduce one or more needles into a fibroid tumor under visual control. Bipolar radiofrequency current is then delivered between two adjacent needles, or monopolar current between a single needle and a distant dispersive electrode affixed to the thigh or back. The aim of needle myolysis is to coagulate a significant volume of the tumor and thereby cause it to shrink substantially. The traditional technique is to make multiple passes through different areas of the tumor using the coagulating needle to destroy many cylindrical cores of abnormal tissue. However, the desirability of multiple passes is mitigated by the risk of adhesion formation, which is thought to increase with increasing amounts of injured uterine serosa and by the operative time and skill required.

For these and other reasons, it would be desirable to provide a minimally invasive method and device to selectively eradicate fibroid tumors within the uterus. It would be desirable if the method and device could locate and treat all types of fibroids in the uterus in a safe and effective manner with minimum risk and discomfort for the patient. It would be further desirable to provide a method and device for eradicating fibroid tumors that combines imaging and treatment in one simple hand held device. At least some of these objectives will be met by the methods and devices of the present invention described hereinafter.

2. Description of the Background Art

BRIEF SUMMARY OF THE INVENTION

In a first aspect of the present invention, methods for minimally invasive identification and treatment of submucosal, intramural, or subserosal fibroids of the uterus are provided. A sheath, catheter, or probe may be transcervically introduced into the uterus. A location of the fibroid tumor may be determined by using a visualization element within or on the sheath. Preferably, the physician will be able to image the tumors transendometrially from within the uterine cavity. The visualization element may comprise an ultrasonic element or other visualization means, such as hysteroscopy, that is capable of producing a visual image. Once having identified the location, a portion of the sheath is steered to position at least one treatment needle at the determined location. The needle is anchored within the uterine tissue and the fibroid is treated with the needle. Fibroid treatment may take several forms as discussed in more detail below. Generally, each individual fibroid tumor will be navigated to, imaged, targeted and treated separately. It will further be appreciated that external imaging may be preformed prior to sheath introduction so as to initially “map” the location of the fibroid tumors.

Anchoring comprises manually positioning and penetrating the treatment needle through an endometrium so as to engage the fibroid. Preferably, the visualization element not only provides a field of view for locating the fibroid but also provides a field of view for directly observing and verifying needle deployment and fibroid treatment in real-time. Visualization may be aided by steering, rotating, or deflecting the visualization element independent of the treatment needle so as to provide a complete view. At least one treatment needle, preferably two treatment needles, will be anchored in the uterine tissue so that the needles will remain substantially immobile during the delivery of treatment. For example, anchoring may comprise deploying at least two treatment needles in a converging manner so as to pinch the fibroid therebetween. Alternatively, anchoring may comprise deploying at least two treatment needles in a diverging manner so as to hook the fibroid therebetween. Still further, anchoring may comprise deploying at least two treatment needles in a telescoping manner.

The uterine fibroid may be treated in several ways. Usually the fibroid will be treated by delivering ablative energy to the fibroid with the needle to necrose the tissue. The ablative energy may comprise electrically energy (e.g., radiofrequency energy, laser energy, or microwave energy), freezing energy (e.g., cryo energy), ultrasound energy, high intensity focused ultrasound (HIFU), or radiation. Preferably, the treatment needle comprises electrically conductive electrodes that deliver ablative radiofrequency energy in a bipolar or monopolar fashion. In addition to or in lieu of ablative energy treatment, the fibroids may be treated by delivering at least one therapeutic agent to the fibroid with the needle. Still further, and in addition to or in lieu of energy and/or drug delivery treatments, the fibroid may be treated by mechanical cutting. For example, the fibroid may be morcelated with a tip of the needle. The treatment needle or other elements (e.g., non-treatment needle, thermocouple) may additionally monitor tissue impedance and/or measure a tissue temperature so as to aid in diagnosis, blood supply measurement, thermal signature, tissue targeting, and the like.

In another aspect of the present invention, minimally invasive devices for imaging and treating submucosal, intramural, or subserosal fibroids in one real-time system are provided. The device comprises a sheath, probe, catheter, or other shaft which is adapted for transcervical introduction into a uterus. A visualization element is within or on a distal steerable portion of the sheath. The visualization element is capable of determining a location of a fibroid on wall of the uterus while the sheath is in the uterus. Typically, the visualization element comprise an ultrasonic transducer. For example, the visualization element may comprise a phased array transducer having 64 elements or a mechanically scanned transducer. Still further, the element may comprise other visualization means, such as hysteroscopy, that is capable of producing a visual image. At least one self-anchoring treatment needle is within or on a distal portion of the sheath. The treatment needle is deployable against the fibroid whose position has been located by the visualization element.

The at least one treatment needle, usually two treatment needles, will be anchored by providing a geometry which inhibits displacement after the needles have been deployed. Exemplary geometries include non-linear, such as arcuate, helical, such as cork screw, curved, co-axial, everting, and like configurations. For example, the geometry may comprises a pair of converging or diverging needles which when deployed in tissue will remain firmly anchored as a result of the opposed geometry. Such geometries may be conveniently referred to as being “self-anchoring.” Such anchoring needles advantageously provide targeted treatment of larger volumes (e.g., larger fibroids) with less damage to non-target tissue. The treatment needle may take on a variety of forms, typically having both extended and retracted configurations, and be made from a variety of materials (e.g., nitinol). For example, the treatment needle may comprise electrodes, electrosurgical needles, or other tissue-penetrating elements capable of delivering ablative radio-frequency energy to target and treat the tumors. Alternatively, the treatment needle may comprise an antenna capable of delivering microwave energy to treat the fibroid. Further, the treatment needle may comprise a hollow tube so as to deliver at least one therapeutic agent to the fibroid. Still further, the treatment needle may comprise a cutting tube so as to morcelate the fibroid.

The visualization element will preferably be located near and/or coupled to the treatment needle so that needle positioning, deployment, and treatment is within a surgeon's field of view. The sheath, visualization element, and/or treatment needle may be integrally formed or comprises separate, modular components that are coupleable to one another. For example, the visualization element may comprise a re-usable ultrasound core that may be positioned within a disposable needle carrying sheath. Further, at least a portion of the sheath, visualization element, and/or treatment needle may be steerable, rotatable, deflectable, flexible, pre-shaped, or pre-formed so as provide transvaginal access to the uterus for identification and treatment of fibroids. An exemplary interventional deployment and imaging system is described in more detail in U.S. Provisional Patent Application Ser. No. 60/758,881, filed Jan. 12, 2006, which is assigned to the assignee of the present application and incorporated herein by reference.

A further understanding of the nature and advantages of the present invention will become apparent by reference to the remaining portions of the specification and drawings.

DETAILED DESCRIPTION OF THE INVENTION

Referring now toFIGS. 1A through 1F, a first embodiment of the invention is illustrated including two converging ablation needles14and an ultrasound imaging module12. A flexible, steerable catheter10is shown that acts as a sheath for the ultrasound catheter12. InFIG. 1A, the two treatment needles14are in a retracted configuration within the sheath10. InFIG. 1B, the ultrasound catheter12is shown within the sheath10with the two treatment needles14in a deployed configuration. One or both converging ablation needles14may have insulating sleeves so as to prevent treating non-target tissue and/or thermocouples at a tip region to measure a tissue temperature.FIG. 1Cshows application of radiofrequency ablation energy between the two bipolar needle electrodes14and the resulting energy field16therebetween.FIG. 1Dshows the sheath10inserted into the uterus18via the cervix20with a flexible shaft portion22. As described above, the ultrasound beam12not only allows for identification of the fibroids24,26, but also serves to provide real-time visualization of needle anchoring and ablation treatment. The ultrasound catheter12may further be steered, rotated, or deflected independently of the treatment needles14so as to allow for a complete reconstruction view. For example, the ultrasound catheter may be torqued or rotated so that positioning of both needles14and treatment16may be verified.FIG. 1Eshow deployment of the treatment needles14during ultrasound visualization whileFIG. 1Fshows radiofrequency ablation treatment16of the fibroid tumor24. Generally, each individual fibroid tumor24,26will be navigated to, imaged, targeted and treated separately. It will be appreciated that the above depictions are for illustrative purposes only and do not necessarily reflect the actual shape, size, or dimensions of the device. This applies to all depictions hereinafter.

Referring now toFIGS. 2A through 2D, a second embodiment of the invention is illustrated including two diverging ablation needles28and the ultrasound imaging module12. Again, the flexible, steerable catheter10is shown acting as a sheath for the ultrasound catheter12. InFIG. 2A, the ultrasound catheter12is inserted into the sheath10and is visualizing the fibroid tumor24within the uterus as denoted by the dashed lines30. A hollow nitinol needle32is deployed through a lumen34in the sheath10as illustrated inFIG. 2B. Thereafter, two hooked treatment needles28are deployed through the hollow needle32as illustrated inFIG. 2Cand anchored against the fibroid24. Radiofrequency ablative energy is then delivered in a bipolar fashion between the two poles of the hooked treatment needles28so as to necrose the fibroid tissue24as illustrated inFIG. 2D. Fibroid identification, needle deployment, and ablation treatment are carried out under ultrasound visualization30in real-time. It will be appreciated that the distances (as denoted by arrows36,38) that each treatment needle28is deployed within the fibroid tissue24may be adjusted based on the size of the lesion.

Referring now toFIGS. 3A through 3D, a third embodiment of the invention is illustrated including a telescoping ablation needle40and the ultrasound imaging module12. Again, the flexible, steerable catheter10is shown acting as a sheath for the ultrasound catheter12. As shown inFIG. 3A, the ultrasound catheter12is inserted into the sheath10. The sheath10is transcervically introduced into the uterus and used for visualizing the fibroid tumor24as denoted by the dashed lines30. Similar toFIG. 2B, a first nitinol needle32is deployed through the lumen34in the sheath10. Thereafter, a second telescoping needle40is deployed through the first needle32as illustrated inFIG. 3C. Radiofrequency ablative energy is delivered in a bipolar fashion between the two telescoping needles40,32under ultrasound visualization30. Again, the distance (as denoted by arrow42) that the telescoping treatment needle40is extended within the fibroid tissue24may be adjustable to the size of the lesion.

Referring now toFIGS. 4A through 4F, a fourth embodiment of the invention is illustrated including an inflatable treatment balloon44and the ultrasound imaging catheter12. As shown inFIG. 4A, the flexible, steerable sheath10is inserted into the uterus18via the cervix20with the ultrasound module12on board. The sheath10further has a lumen for insertion of a rotary cutting tube46, treatment needle, or other penetrating device.FIG. 4Billustrates visualization of the individual fibroid tumor24from within the uterine cavity18by the ultrasound module12, as denoted by the dashed lines30.FIG. 4Cillustrates advancement and penetration of the rotary cutting tube46into the fibroid tumor24under direct visualization30through the ultrasound module12. The distal end of the rotary cutting tube46is depicted with a morcelating tip47. InFIG. 4D, some of the fibroid tissue24is removed through the rotary cutting tube46to create room for the treatment balloon44. The rotary cutting tube46is further partially retracted to make room in the tumor24for the treatment balloon44. As shown inFIG. 4E, the treatment balloon44is then deployed through the cutting tube46and into the tumor24under direct visualization30through the ultrasound module12. As shown inFIG. 4F, the treatment balloon44is inflated and ablative energy is applied by the balloon44to treat the tumor24under direct visualization30through the ultrasound module12. The ablative energy may comprise any of the energy sources described herein including radiofrequency energy, microwave energy, laser energy, cryo energy, ultrasound energy, HIFU, or radiation. Alternatively or in addition to the treatment balloon44, a radiofrequency basket electrode may be disposed over the balloon to treat the tumor.

Referring now toFIGS. 5A through 5C, a fifth embodiment of the invention is illustrated including the inflatable treatment balloon44and the ultrasound imaging catheter12ofFIG. 4F. This embodiment differs in how the treatment balloon44is deployed into the tumor24. After identification of the fibroid tumor24from within the uterine cavity18, a rotary cutting tube48without a morcelating tip is advanced and penetrated into the fibroid tumor24under direct visualization30through the ultrasound module12as shown inFIG. 5A. A wire50is then advanced into the tumor24through the cutting tube48under direct visualization30through the ultrasound module12inFIG. 5B. InFIG. 5C, the treatment balloon44is advanced through the cutting tube48and over the wire50and then inflated in the tumor24under direct ultrasound visualization30so as to treat the tumor24with ablative energy. The ablative energy may comprise any of the energy sources described herein including radiofrequency energy, microwave energy, laser energy, cryo energy, ultrasound energy, HIFU, or radiation.

Referring now toFIG. 6, a sixth embodiment of the invention is illustrated including the rotary cutting tube46and the ultrasound imaging catheter12ofFIG. 4C. This embodiment differs in that the rotary cutting tube46itself provides treatment of the tumor24with its mechanical cutting element having a morcelating tip47. After identification of the fibroid tumor24and advancement/penetration of the rotary cutting tube46into the fibroid tumor24under direct visualization30through the ultrasound module12in the uterus18, the fibroid24is morcelated or liquefied by the rotary cutting tube46and the fibroid tissue24is suctioned out through the hollow cutting tube46as depicted by reference numeral52.

Referring now toFIGS. 7A through 7C, a seventh embodiment of the invention is illustrated including a drug delivery needle54and the ultrasound imaging catheter12. InFIG. 7A, under ultrasound visualization in the uterus, two treatment needles54are anchored within the fibroid24and the fibroid treated by the delivery of at least one therapeutic agent56to the fibroid with the needles54. It will be appreciated that the treatment needles54may have both a retracted and extended position and may be adjustable so as to achieve the desired drug delivery profile. Further, drug delivery may take place though a single treatment needle54or through multiple treatment needles54. The therapeutic agent56may comprise a variety of agents. For example, the agent56may comprise a chemotherapeutic or chemoablative agent (e.g., alcohol or a chemokine), a gene therapy agent, a tissue necrosis agent, an antibody, or the like. The drug delivery needles54may treat tumors of various sizes. For example,FIG. 7Billustrates treatment of a large tumor24′ (e.g., 40 mm), whileFIG. 7Cillustrates treatment of a smaller tumor24″ (e.g., 20 mm).

Referring now toFIG. 8, another drug delivery method and device is illustrated. A syringe58is used to laproscopically inject contrast bubbles60containing at least one therapeutic agent56into the fibroid24instead of transcervical drug delivery via treatment needles54. After drug delivery injection into the fibroid24, the ultrasound imaging catheter12in the uterus18activates the agent56by targeted ultrasound30. For example, this may cause the bubbles60to burst or break in the fibroid blood supply24which in turn releases the therapeutic agent56to the fibroid24for treatment.

Referring now toFIG. 9A, the flexible, steerable catheter10is shown inserted into the uterus18via the cervix20. The catheter10has an on board ultrasound imaging module12and a lumen for insertion of at least one needle62or other penetrating device. In this illustration, multiple needles62are shown inserted into the fibroid tumor24with impedance monitoring to denote the change in the impedance of the tissue from inside the tumor24versus tissue outside the tumor24and/or tissue outside the uterine wall. Impedance monitoring will aid in directly targeting the fibroid tumor24for treatment (e.g., energy delivery, drug delivery, mechanical cutting, etc.) and may also safely control treatment delivery so that it is only within the uterus18itself. Further, impedance profiling may denote border recognition of tissue. This in turn may allow for implementation of additional safety mechanisms. For example, automatic shutoff of the device may be implemented if the needle62is extended beyond the fibroid24and/or uterus18.

Referring now toFIG. 9B, the flexible, steerable catheter10is shown inserted uterus18via the cervix20. The catheter10has an on board ultrasound imaging module12and a lumen for insertion of at least one needle64or other penetrating device. The needle64is shown inserted into the fibroid tumor24with impedance monitoring to denote the change in the impedance of the tissue from inside the tumor24versus tissue outside the tumor and/or tissue outside the uterine wall. Impedance monitoring will aid in directly targeting the fibroid tumor24for treatment from the uterine wall.

Referring now toFIG. 10, a flexible, steerable laparoscopic probe10is shown accessing the uterus18from an abdominal port66in the abdominal wall68. The probe10uses the ultrasound module12outside of the uterus18to target fibroid tumors24that are within the uterus18. The probe10then uses the treatment needle70under direct visualization30through the ultrasound module12to then treat the fibroid24with ablative energy.

Referring now toFIG. 11A, a flexible, steerable catheter based probe10having a treatment needle72is shown inserted into the uterus18and within the fibroid24using a non-coupled vaginal ultrasound probe74. The two devices10,74are operated independently of each other. Referring now toFIG. 11B, the flexible, steerable needle catheter10is shown inserted into the uterus18and the treatment needle72within the fibroid24using a non-coupled abdominal ultrasound probe76. The two devices10,76are operated independently of each other. With respect toFIG. 11C, the flexible, steerable laparoscopic needle probe10is shown accessing the uterus18from an abdominal port66in the abdominal wall68. The treatment needle70of the probe10is shown accessing the fibroid24with the aid of ultrasound visualization30from the abdominal ultrasound probe76. The two devices70,76are operated independently of each other.

Referring now toFIG. 12, a flexible, steerable intrauterine ultrasound imaging device78is shown for imaging the uterine wall and lining transendometrially for the diagnosis of fibroids24,26. The ultrasound imaging head82generally comprises an ultrasonic phased array transducer having 64 elements. The ultrasound transducer may also be mechanical, linear, or curved. A sterile drape80may be placed over the diagnostic imager78, wherein a gel may be used within the drape80for improved image coupling. The diagnostic imager78may also be used without a drape80, when disposable, using natural body fluids for image coupling. The diagnostic imager78further has a flexible section84capable of deflection in a range from 0 degrees to about 90 degrees via an angle adjustment knob86. The diagnostic ultrasound imager78is inserted directly into the uterine cavity18, either with or without dilation of the cervix20, in order to directly image the fibroids24,26within the wall of the uterus18. This imaging provides a closer and more direct view of the tumors24,46in order to more accurately diagnose the location and characterization of the fibroids or other pathology.

FIGS. 13A and 13Billustrate schematics of a system constructed in accordance with the principles of the present invention. The system comprises a combined ultrasound recognition and radiofrequency treatment system88. The system88may provide a variety of features including ultrasound mapping, ultrasound recognition of treatment area (e.g., tissue differentiation via temperature profiling), radiofrequency ablation treatment under ultrasound imaging, temperature monitoring, time monitoring, and/or impedance monitoring. The system88may be coupled to various devices90described herein having single or multiple treatment needle configurations to ablate in either bipolar or monopolar modes.

Although certain exemplary embodiments and methods have been described in some detail, for clarity of understanding and by way of example, it will be apparent from the foregoing disclosure to those skilled in the art that variations, modifications, changes, and adaptations of such embodiments and methods may be made without departing from the true spirit and scope of the invention. Therefore, the above description should not be taken as limiting the scope of the invention which is defined by the appended claims.