Device for fallopian tube diagnosis

Abstract

To provide a device for diagnosing the fallopian tubes in a minimally invasive manner. A catheter for fallopian tube diagnosis includes a tube (10) having a distal end and positionable relative to a fallopian tube (1), and balloons (12, 14) having proximal and distal ends. The balloon is coupled to the distal end of the tube at the balloon's proximal end and is movable between a first folded position and a second unfolded position, thereby enabling the balloon to be extended to the second unfolded position within the fallopian tube. The catheter also includes a push wire (206) attached to the balloon and an actuator (220) for controlling advancement of the push wire to unfold the balloon in a controlled manner when pressurized.

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims the benefit of priority of U.S. Application No. 15 / 053,568, filed on February 25, 2016, the content of which is incorporated herein by reference.

[0002] The present invention generally relates to fallopian tube diagnosis, and more particularly to catheters and diagnostic collection devices that address the anatomical difficulties associated with navigation within the fallopian tubes.

Background Art

[0003] Ovarian cancer is a serious disease in women, and 1 in 72 women in the United States will be diagnosed with ovarian cancer during their lifetime. In 2012, 22,280 women in the United States were diagnosed with this disease, and 15,500 women died from this malignancy. Ovarian cancer is very lethal because there is no clear early detection or screening test for this type of cancer, meaning that most cases of ovarian cancer are not diagnosed until they reach an advanced stage. Therefore, ovarian cancer screening is a high clinical concern because this disease cannot be detected at the early stage when it is generally most curable.

[0004] Currently, definitive detection of ovarian cancer requires a surgical procedure to obtain a cell sample for diagnosis. Since the ovaries are located within the abdominal cavity, laparoscopy or open surgery (laparotomy) is necessary to access the ovaries for evaluation. Additionally, ovarian biopsy is generally not recommended in clinical guidelines because there is a risk of spreading the cancer.

[0005] Anatomically, the ovaries are close to the fallopian tubes in the region of the distal opening of the fallopian tubes. The eggs released from the ovaries are collected by the fallopian tubes and transported through the fallopian tubes to the uterus. In ovarian cancer, cells can deposit in the fallopian tubes, and some of these cells may seek their way into the uterus. Cell samples obtained from the uterus can detect ovarian malignancies, but the incidence of the migration of ovarian cancer cells to the uterus is too low to provide uterine sampling for a reliable diagnostic test for ovarian malignancies. More ovarian cancer cells migrate to the fallopian tubes, and this number increases near the distal part of the fallopian tubes, near the distal opening. The ability to examine cells in the fallopian tubes for malignancies would be quite clinically valuable for the early detection and treatment of such cancers if it could be done without disturbing the dispersion of cancer cells. In addition, there is a need to distinguish ovarian cancer from fallopian tube cancer based on the discovery of abnormal cells in the fallopian tubes for several reasons, including various treatment plans between them.

[0006] However, the introduction of a diagnostic device into the fallopian tubes is a problem because the fallopian tubes are very fragile and tend to perforate during the passage of most devices. Such perforations generally occur at the uterotubal junction (UTJ), which is a constriction that occurs approximately 1 cm distal to the proximal opening of the fallopian tube in the uterus. The lumen size of this constriction is as small as about 0.3 mm or 0.5 mm, and the lumen size of the fallopian tube adjacent to the uterotubal junction is about 1 mm. Figure 1 shows a cross-sectional view of the fallopian tube 1 connecting the uterus 4 to the ovary 6, and the fallopian tube 1 has a uterotubal junction (UTJ) 2.

Summary of the Invention

Problems to be Solved by the Invention

[0007] Therefore, there is a need for a device and process that can obtain cell samples from the fallopian tubes for the evaluation of ovarian cancer in a minimally invasive manner, especially without the need for a skin incision. Furthermore, there is a need to secure samples of representative cells from the fallopian tubes using a catheter for examining early-stage cancer.

Means for Solving the Problem

[0008] Disclosed are a method and a device for performing a minimally invasive procedure useful for fallopian tube diagnosis. In at least one embodiment, the proximal opening of the fallopian tube is accessed by an intrauterine approach, a guiding catheter is advanced, a cannula is inserted to form a fluid-tight seal with the proximal opening of the fallopian tube, a second catheter inside the guiding catheter is advanced along the length of the fallopian tube and out into the abdominal cavity, the balloon at the end of the second catheter is inflated, the second catheter is retracted until the distal opening of the fallopian tube is sealed by the balloon, irrigation is performed substantially along the length of the fallopian tube, and the irrigation fluid is collected for cytology or cell analysis.

[0009] The present invention will be described in detail with respect to the following non-limiting specific embodiments of the present invention. It should be understood that the claims are not limited to the specific devices described in detail.

Brief Description of the Drawings

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BEST MODE FOR CARRYING OUT THE INVENTION

[0011] The present invention is useful for engaging with the inner wall of the fallopian tube for diagnostic purposes and efficiently retrieving cells therefrom. The device and process are provided for the collection of such cells in minimally invasive procedures that, in some embodiments, are performed without an incision.

[0012] When a range of values is given, it should be understood that, unless the context clearly dictates otherwise, each intervening value between the upper and lower limits of that range is also clearly disclosed down to the unit of one tenth of the lower limit. Each smaller range between any specified value or intervening value within the specified range and any other specified or intervening value within that specified range is included within the present invention. The upper and lower limits of these smaller ranges can independently be included within or excluded from the range, and each range where either, neither, or both of the upper and lower limits are included within that smaller range is also included within the present invention. When the specified range includes one or both of the upper and lower limits, ranges excluding either or both of these included upper and lower limits are also included within the present invention.

[0013] As used herein and in the appended claims, it should be noted that the singular forms "a", "an", and "the" include the plural referents unless the context clearly dictates otherwise. Thus, for example, a reference to "a balloon" includes a plurality of such balloons, and a reference to "a channel" includes a reference to one or more channels and their equivalents known to those skilled in the art.

[0014] Embodiments of the catheter of the invention for fallopian tube diagnosis are provided for performing minimally invasive procedures, including: (1) access to the proximal opening of the fallopian tube via an intrauterine approach; (2) advancement of an introducer catheter for inserting a cannula to form a fluid-tight seal with the proximal opening; (3) use of a second catheter inside the introducer catheter to advance along the length of the fallopian tube and exit into the abdominal cavity; (4) retraction of the second catheter until a balloon at the end of the second catheter seals the distal opening of the fallopian tube, and inflation of the balloon at the end of the second catheter (retraction of the second catheter causes contact with the inner surface of the fallopian tube lumen, separating cells for improved sampling); and (5) perfusion of the fallopian tube and collection of a perfusion fluid for cytology or cell analysis.

[0015] Also, specific embodiments of the catheter of the invention for fallopian tube diagnosis are provided for performing minimally invasive procedures, including: (1) access to the proximal opening of the fallopian tube via an intrauterine approach; (2) advancement of an introducer catheter for inserting a cannula into the proximal opening; (3) use of a second catheter inside the introducer catheter that advances inside the fallopian tube (an inflatable balloon at the end of the second catheter advances across the proximal portion of the fallopian tube and further inverts into the fallopian tube); (4) the balloon contacts the inner surface of the fallopian tube lumen to scrape cells for improved sampling; and (5) the balloon is removed and inserted into a vial for cell collection and then processed.

[0016] Embodiments of the catheter of the invention are configured to be inserted into the fallopian tube, which is generally very difficult. The fallopian tube is curved, the soft tissue of the tube collapses, and attempting to pass through it leads to multiple contractions. This is especially true at the uterotubal junction (UTJ), where medical devices tend to penetrate when inserted in a constricted state that occurs approximately 1 cm distal to the proximal opening (ostium) of the fallopian tube within the uterus. Also, the uterotubal junction (UTJ) typically exhibits a downward bend with an inner lumen size at contraction that can be about 0.3 mm or 0.5 mm, while the inner lumen size of the fallopian tube adjacent to the uterotubal junction is about 1 mm.

[0017] In at least one embodiment of the present invention, first, an elongated retractable balloon within the catheter lumen is deployed. When pressurized within the catheter, the balloon's folds are returned, and the mechanism for unwinding the folds creates a path through the fallopian tube regardless of the tube's torsion or contraction. Most of the balloon's length is substantially inelastic, such that the balloon does not substantially inflate or expand the fallopian tube when its folds are returned, and preferably, the fallopian tube does not inflate or expand when the balloon's folds are returned. Inflating the balloon may rupture or damage the fallopian tube. However, the design incorporates an elastic distal balloon end that allows sealing of the distal opening when retracting the inflated balloon.

[0018] The process of the present invention common to various embodiments of the device of the present invention includes deployment of the distal end of the catheter. In some embodiments of the present invention, the distal end of the catheter of the invention is delivered to the proximal end of the fallopian tube using a conventional hysteroscope. Regardless of the mode of deployment, the retracted portion of the catheter of the invention extends in contact with the inner wall of the fallopian tube. Surprisingly, it has been found that the action of extending that portion scrapes sufficient cells from the fallopian tube wall for histological evaluation. This is seen on a plane with apparently non-abrasive characteristics. In some embodiments, there is abrasion on the contact surface of the tube, but such abrasion is not considered inevitable. Also surprisingly, it has been found that retracting the expanded portion still removes many cells. In another process of the present invention, the expanded portion is retracted before removing the catheter to prevent the scraped fallopian tube cells from dispersing into the surrounding tissue. Contacting the exposed portion covered with cells here with a microscope slide or other diagnostic substrate is sufficient to test for abnormal cells, specifically cancer cells.

[0019] Referring now to the figures, in FIGS. 2A - 2D, the introducer catheter 10 has an inelastic sleeve 12 that is folded back and an elastic balloon 14 attached thereto. The elastic balloon 14 is inserted through the introducer catheter 10 present within the working channel 22 of the operative hysteroscope 20 (FIG. 3) and is used to insert a cannula into the proximal opening of the fallopian tube 1 (FIG. 2A). The elastic balloon 14 is inflated, the fold of the sleeve 12 is returned over the length of the fallopian tube 1, and the distal elastic balloon 14 is inflated (FIG. 2B). When slightly retracted and the folded elastic sleeve 12 is fully advanced, the inflation of the elastic balloon 14 seals the distal opening 18 of the fallopian tube 1 (FIG. 2C). FIG. 2D shows the introduction of saline for perfusion over the length of the fallopian tube 1 between the introducer catheter 10 and the sleeve 12 with the fold returned. The inflated elastic balloon 14 is retracted, sealing the distal opening, and subsequently, the perfusion fluid is collected and a cell sample is obtained from substantially the entire length of the fallopian tube 1 for cell analysis in the detection of ovarian cancer or other conditions.

[0020] The catheter 10 described above and to be described in more detail later is preferably introduced into the patient's uterus using the operative hysteroscope 20, an example of which is shown in FIG. 3. The operative hysteroscope 20 includes an endoscope and multiple channels. One channel is for irrigation to inflate the uterus and enable visualization by the endoscope, and one or more additional channels 22 enable instruments and / or catheters to be advanced distally of the hysteroscope. The proximal introduction catheter 10 (see FIGS. 2A and 4) can be advanced through the working channel of the operative hysteroscope and can be used to insert a cannula into the proximal opening of the fallopian tube. The balloon 14 on the proximal introduction catheter 10 inflates to occlude the proximal opening, and the repositionable balloon catheter advances through the proximal introduction catheter 10 to the proximal portion of the fallopian tube. The sleeve / balloon element 14 is fully repositioned, and the inflated balloon tip is retracted to seal the distal opening. The irrigation fluid is introduced through the port 11 and aspirated through the irrigation port 11 of the proximal introduction catheter 10 to collect samples. Also, irrigation can be introduced through both the repositionable balloon catheter and the proximal introduction catheter and then aspirated from one or both ports (11, 13).

[0021] In an embodiment of the invention of the catheter, the sleeve 12 of the repositionable sleeve catheter is preferably a flexible, elongated, substantially inelastic tube, and as seen in FIGS. 5A and 5B, an elastic balloon tip 14 is attached to the distal end of the sleeve 12. The inelastic tube 12 preferably has a plurality of ridges 15 along its length, as shown in FIG. 5B, and the ridges 15 are on the outer surface of the tube 12 when the tube 12 is extended / deployed. Before deployment, since the tube 12 is folded back, the ridges 15 are on the inner surface, as shown in FIG. 5A. When the repositioning of the sleeve 12 is fully reversed, as in FIG. 5B, if the ridges 15 are on the outer surface, the ridges 15 are exposed to the luminal surface of the fallopian tube. These ridges 15 increase the ability of the sleeve to collect cells when the balloon is retracted. As a variant, the outer surface of the inelastic tube with the repositioning reversed may be covered with a cloth or other fabric, etc. to increase the separation of cells while the balloon is being retracted.

[0022] Figures 6A-6C illustrate an embodiment of the repositionable sleeve catheter 10A, which provides better protection than the repositionable sleeve catheter provided in the embodiments of FIGS. 5A and 5B by virtue of the connection between the balloon and the sleeve of the repositionable sleeve catheter 10A during deployment. The configuration of the embodiment of FIGS. 6A-6C involves the attachment of an elongate elastic balloon to the distal tip of the repositionable sleeve catheter. A substantially inelastic sleeve 17 that is slightly shorter than the elastic balloon 14 is attached to the elastic balloon 14 at the distal tip of the catheter and is folded back and lies inside the elastic balloon. When returning the fold of the balloon / sleeve combination 14A, the inelastic sleeve 17 emerges from the double wall 19 of the catheter 10A and lies on the outer surface of the elastic balloon, confining the elastic balloon over most of its length and preventing the elastic balloon from expanding and rupturing the fallopian tube while advancing the repositionable sleeve through the fallopian tube. When the balloon / sleeve fold is fully returned, the distal elastic balloon expands up to three to five times the diameter of the sleeve and occludes the distal opening when pulling the catheter back with the inflated balloon retracted. If desired, the catheter may include a port 11 that allows irrigation to occur between the balloon and the outer sleeve.

[0023] Figures 7A - 7C show an embodiment of the retractable sleeve catheter 10B. In the retractable sleeve catheter 10B, a concentric double - wall catheter is provided, and a three - layer retractable portion is attached to the distal catheter tip. (1) An elongated inelastic balloon 21 is attached to the distal tip of the inner catheter 23. The balloon 21 is within the lumen 25 of the inner catheter. (2) An elongated elastic balloon 14B is attached to the distal tip of the outer wall 27 of the catheter 10B. The elastic balloon 14B is equal in length to the inelastic balloon 21 and is inside the inelastic balloon 21. (3) An inelastic sleeve 29 is attached to the distal tip of the outer catheter wall 27. The inelastic sleeve 29 is shorter than the elastic balloon 14B and is inside the elastic balloon 14B. By pressurizing the inner catheter 23, the retraction of the inelastic balloon 21 is reversed, and the elastic balloon 14B and the outer confining sleeve 29 are delivered. When all three layers of retractions are fully reversed, the elastic balloon 14B is inflated by pressurizing between the wall of the inner catheter and the wall of the outer catheter. The inelastic sleeve 29 confines the elastic balloon 14B over most of its length, and the unconfined tip on the distal side of the balloon 14T expands to form an occlusion element. A potential advantage of this design is the reduction of frictional characteristics during the process of reversing the retraction. In this embodiment, the inelastic balloon 21 delivers the elastic balloon and the confining sleeve. The elastic balloon does not inflate until its retraction is fully reversed, thus not increasing the friction with the wall of the retractable sleeve during the reversal of the retraction as in previous embodiments. This has a significant advantage of facilitating deployment, especially when working with small - diameter catheters required to penetrate the fallopian tubes.

[0024] Figures 8A and 8B show an embodiment of the retractable sleeve catheter 10C. The inelastic sheath 29A has a small lumen 31 for irrigation. The lumen 31 is connected to a third port 11A. The third port 11A is used for fluid irrigation and also for suction to obtain a cytology sample.

[0025] Figures 9A - 9E show the modified design. The elongated balloon 32, together with the expandable member 34 attached to its distal end, is folded back into the lumen 36 of the catheter 30. When folded back, the expandable member 34 is inside the elongated balloon 32. In some embodiments of the present invention, the expandable member 34 is a helical portion consisting of multiple loops 38 of filaments. The filaments forming the expandable member 34 can be easily formed from various materials, such materials including, for example, monofilament plastic materials such as nylon or polypropylene, fluoropolymers, or polylactic acid; metals such as stainless steel, titanium, or platinum; superelastic metals such as nitinol. In some embodiments, fiducial markers are present (not shown) to facilitate subsequent return to the location of cell sampling. It should also be recognized that the inflated portion may have a deformed configuration. For example, the inflated portion 34 may include a plurality of outwardly projecting bristles 40 of plastic or metal (Fig. 18), or the inflated portion 34 may assume a curled configuration 38 to a predetermined shape, a (fan - shaped) expanded configuration 42, or a rounded configuration 44 when released from being confined inside the catheter, and may exist as an elongated strand of material (Figs. 11A - 11B or 14A - 14B), or the inflated portion 34 may be a compressible plastic foam that expands when released into a wet environment (Figs. 12A - 12B). When pressurizing the catheter adjacent to the distal opening, the fold of the balloon 32 is reversed, pushing the folded - back portion outward to the extended position and bringing it into contact with the fallopian tube inner wall cells. In some embodiments of the present invention, when the fold of the balloon is fully reversed, the expanded portion 34 is delivered into the peritoneal cavity from the distal opening of the fallopian tube. In some embodiments, the expanded portion 34 has an outer diameter of about 15 - 20 mm.

[0026] The advantage of the extension portion 34 having a plurality of bristles is that it has a large surface area capable of collecting cells, and such a surface area includes an area that is not likely to be exposed to shear forces when the device is retracted. This method can maximize cell collection, as shown in FIGS. 18-20, and minimize the amount of cells wiped off when the device is pulled through the fallopian tube or drawn into the sheath. In these embodiments where the extension portion has a relatively large surface area, cell collection per linear unit of the fallopian tube typically increases and engages as such under conditions such as pressurization compared to an extension portion without a contour.

[0027] In still other embodiments of the catheter of the present invention, the extension portion may have the following configurations when deployed, and such configurations are, for example, a plurality of filaments (FIGS. 11A-11B) attached to the distal end of the balloon 32 and spreading outward when the balloon is folded back to form a brush 42; a plastic foam structure 46 (FIGS. 12A-12B) compressed inside the balloon 32 and expanding when the balloon 32 is folded back to expose it to the fluid environment; an elastic or inelastic balloon 48 (FIGS. 13A-13B) at the distal end of the non-elastic sleeve balloon 32, a folded balloon with a superelastic wire coil (FIGS. 14A-14B), a helical folded balloon 50 (FIGS. 15A-15B), a folded distal arc balloon 52 (FIGS. 16A-16B); or plastic or metal elastic elongated filaments that gather into a three-dimensional structure when the balloon is folded back, such as the lumen 54 (FIGS. 17A-17B), and an expansion portion 34 having a plurality of outwardly directed bristles (FIG. 18). It should be recognized that any of these embodiments of the extension portion of the catheter of the present invention can be easily adapted to fiducial markers used to navigate back into the fallopian tube when necessary. Such markers are known in the art and include, for example, radiopaque markers, isotope markers, and radio frequency markers. In still other embodiments, the biodegradable extension portion or the permanent extension portion is detached from the catheter. In still other embodiments, the extension portion delivers a therapeutic agent for fallopian tube tissue, such as a chemotherapeutic agent, an antibiotic, an anti-inflammatory agent, or a combination thereof.

[0028] When the catheter is drawn into the working channel of the hysteroscope, cells are separated from the entire length of the inner surface of the fallopian tube. In some embodiments, to protect the collected cells within the inner bore of the catheter tip region, the extension is folded back by a decrease in gas pressure using a balloon (Figure 19).

[0029] While not intending to be bound by any particular theory, in some examples of the non-contoured inflatable portion, the inflatable portion creates sufficient friction between the outer surface of the inflatable portion and the inner lining of the fallopian tube to separate the cells and attach them to the inflatable portion. The inflated spiral at the distal end of the balloon contacts the fimbria at the distal end of the fallopian tube and collects the cell sample when pulling on the spiral. Since the inner diameter of the fallopian tube increases from the proximal side towards the distal end, the inflatable portion ensures that the cell sample is obtained at the distal end of the fallopian tube (the fimbrial portion of the fallopian tube). In some embodiments of the procedure, the elongated balloon and the distal inflatable portion are drawn into the working channel of the hysteroscope to avoid loss of the cell sample when removing the hysteroscope from the patient. The elastomeric seal at the proximal end of the working channel of the hysteroscope seals against the outer surface of the catheter. Marks on the catheter body indicate the draw length necessary to ensure that the elongated balloon and the distal spiral are within the working channel of the hysteroscope. When removing the hysteroscope from the patient, in some embodiments, a syringe containing a physiological saline solution is attached to the luer fitting at the proximal end of the working channel, and the physiological saline is used to wash the cells collected by the elongated balloon and the inflated spiral into a test tube. It should be appreciated that the cells attached to the inflatable portion are readily collected by conventional techniques for testing and prepared for cytological, molecular, or genetic testing.

[0030] In a modified embodiment of the catheter shown in FIGS. 17A - 17B, where the coil is attached to the end of the retractable balloon, a lumen formed of polyethylene terephthalate (PET) of an exemplary material is provided. The retraction process follows the process of the foregoing embodiments. This modified embodiment includes an inflation side port and a proximal seal, and the proximal seal enables the balloon to be retracted while maintaining an orifice through the lumen for fluid communication between the hysteroscope and the patient's body tissue. When retracted, the lumen constitutes a passage through which another dilation portion or surgical instrument package passes. An example of such a collection device is the spiral shape shown in FIGS. 19 and 20. It should be recognized that when removing the device, in order to prevent the possibility that distal cells are wiped off by the inner surface on the proximal side of the fallopian tube, the cells may be collected from a specific portion of the fallopian tube, for example, the fimbria, and then drawn back into the lumen.

[0031] Figures 21A and 21B are schematic cross-sectional side views of a ball tip retractable balloon catheter according to at least one embodiment of the present invention. The spherical ball 122 is attached to the distal end of the spring tip 124 fixed to the catheter 126 and is configured to smoothly pass through the uterotubal junction (UTJ) without making a hole through the side wall of the patient's uterotubal junction (UTJ). The spring tip 124 and the spherical ball 122 have an open lumen 128 extending through the spring tip 124 and the spherical ball 122. The spherical ball 122 on the spring tip 124 has a diameter of about 0.8 - 1.0 mm, and the hollow spring tip 124 has a length of about 1.5 cm and an outer diameter of about 0.6 mm. The hollow spring tip 124 is preferably a metal (stainless steel or superelastic metal, such as nitinol) coil spring, and has a sheath of a thin plastic heat shrinkable tube made of nylon, PET (polyethylene terephthalate), or a similar material on its outer surface. In a particular embodiment of the present invention, the spring tip 124 may be a metal coil spring co-extruded into a tubular plastic body. Also. The hollow spring tip 124 may be a flexible plastic tube made of nylon, polyethylene terephthalate (PET), polyether block amide (PEBAX®), or a similar material. The long retractable balloon 130 is located inside the hollow spring tip 124. The retractable balloon 130 extends proximally inside the main lumen 132 of the introducer catheter 126 (a generally flexible tubular structure) or the cannula (a generally synthetic tubular structure), and the proximal end of the retractable balloon 130 is attached to a push rod 134 that penetrates a seal 136 at the proximal end of the catheter 126 or the cannula. When used in a patient's surgery, the flexible ball tip 122 is advanced by hand to pass through the uterotubal junction. Once the flexible ball tip 122 and the spring tip 124 have successfully passed through the uterotubal junction, the push rod 134 is advanced to penetrate the pre-pressurized seal 136 of the introducer catheter 126 or the cannula. The advancement of the push rod 134 controls the return of the fold of the balloon 130 that exits from the hollow spring tip 124 over the length of the fallopian tube.

[0032] In an embodiment of the present invention, when initially deploying an elongated balloon that was folded back within the catheter lumen, the balloon is folded back under pressure inside the catheter, and the folding unwind mechanism follows the fallopian tube regardless of the torsion or contraction of the fallopian tube. Most of the length of the balloon should be substantially inelastic, so that when the balloon is folded back, the balloon does not substantially inflate or deflate the fallopian tube, and the fallopian tube does not expand or dilate when the folding of the balloon is reversed. The inflation of the balloon may rupture or damage the fallopian tube.

[0033] The method of the present invention common to various embodiments of the device of the present invention includes the deployment of the distal end of the catheter. In some embodiments of the present invention, the distal end of the catheter of the present invention is delivered to the proximal end of the fallopian tube using a conventional hysteroscope. Regardless of the deployment mode, the retractable portion of the catheter of the present invention extends to contact the inner wall of the fallopian tube. Surprisingly, it has been found that the action of extending the retractable portion scrapes off sufficient cells from the fallopian tube wall for histological evaluation. This was observed for a plane of characteristics that were not visibly scraped. In some embodiments, there is scraping on the contact surface of the tube, but such scraping is considered not inevitable. Also surprisingly, it has been found that the retraction of the expanded portion still separates many cells. In another process of the present invention, the expanded portion is retracted before removing the catheter so as to prevent the separated fallopian tube cells from dispersing into the surrounding tissue. Contacting the exposed portion covered with cells here with a microscope slide or other diagnostic substrate is sufficient to test for abnormal cells, particularly cancer cells.

[0034] The catheter 126, described above and to be described in more detail later, is introduced into the patient's uterus using the operative hysteroscope 40, an example of which is shown in FIG. 3. The operative hysteroscope includes an endoscope and multiple channels. One channel is preferably for irrigation to inflate the uterus and enable endoscopic visualization, and one or more additional channels enable advancing instruments and / or catheters distally of the hysteroscope. The catheter 126 (see FIGS. 21A and 21B) is advanced through the working channel of the operative hysteroscope, and a cannula is inserted into the proximal opening of the fallopian tube using the catheter 126. The retractable balloon 130 is advanced through the proximal catheter 126 into the proximal portion of the fallopian tube.

[0035] FIGS. 22A-22C are a series of views of the retractable balloon 130 emerging from the nylon flexible tip 152 having the spherical ball 122 according to an embodiment of the present invention. The nylon flexible tip 152 and the spherical ball 122 are configured to pass through the patient's uterotubal junction (UTJ) for deployment of the retracted balloon 130 within the fallopian tube. In some embodiments of the present invention with a nylon ball tip, the retractable balloon catheter 150 is configured to have a 0.9 mm ball tip on a nylon tip having a diameter of 0.66 mm and a length of 18 mm, i.e., a 4Fr (1.27 mm) catheter having a manually retractable balloon with a diameter of 0.64 mm that passes through and returns beyond the tip (24 atm; 2.4×10 6 Pa).

[0036] FIG. 23A is a schematic cross-sectional view showing the sheath-equipped retractable balloon tip catheter 160 or cannula according to an embodiment of the present invention as shown in the view of FIG. 23B. The long retractable balloon 130 having an outer diameter of about 0.8-1.0 mm is retracted about 1-3 cm, most preferably 1.2-1.5 cm in length, outside the distal end of the catheter 126 or cannula. The balloon 130 is inflated to about 14-24 atm (206-353 psi; 1.4×10 6 ~2.4×10 6Inflate the fluid to the pressure of Pa). The pressurized balloon 130 has a rounded end and has a certain degree of flexibility over the length of the balloon 130, and also has sufficient longitudinal strength to allow the balloon 130 to be advanced by hand through the uterotubal junction. In certain embodiments, the balloon 130 is composed of a thin plastic material such as polyethylene terephthalate (PET), polyethylene, nylon, or a material similar thereto, and the balloon 130 has a wall thickness of about 0.25 mil (0.00025”; 0.00635 millimeters). The balloon is preferably an opaque color to facilitate visualization during use. The length of the balloon 130 when fully retracted is about 7 cm, and when fully retracted, the balloon 130 extends into the patient's fallopian tube after a good advancement of 1.5 cm of the length of the retracted balloon passing through the uterotubal junction. The retraction of the balloon 130 is performed in a controlled manner by advancing the push rod 134 so as to penetrate the fluid-tight seal 136 at the proximal end of the catheter 126. At least a portion 167 of the catheter 126 is preferably transparent, whereby the movement of the balloon 130 can be seen through the hysteroscope into which the catheter is inserted, allowing the user to directly observe the insertion procedure. The catheter 126 may be composed of a polymer such as nylon (preferred), Pebax®, polyurethane PET (polyethylene terephthalate), polyethylene, or polyvinyl chloride (PVC) plastic, with or without a polymer or metal coil or braided reinforcement.

[0037] However, the balloon having the above-described dimensions of 1.5 cm in length when folded back out of the catheter 126 or cannula may not remain straight, rather, the balloon 130 may assume a curved configuration of either a single C-shaped curve or an S-shaped curve. However, inserting a cannula having a curved balloon into the proximal opening of the fallopian tube and advancing it through the uterotubal junction is difficult or nearly impossible. It is preferable to straighten the 1.5 cm length of the folded-back balloon 130 by using an outer plastic sheath 162, which is positioned coaxially with the catheter 126 or cannula and covers the 1.5 cm folded-back balloon tip. At least a portion 167 of the sheath 162 is preferably transparent, whereby the movement of the balloon 130 can be seen through the hysteroscope into which the catheter is inserted, enabling the user to directly observe the insertion procedure. The sheath 162 may be composed of a polymer such as nylon (preferred), Pebax®, polyurethane PET (polyethylene terephthalate), polyethylene, or polyvinyl chloride (PVC) plastic, with or without a polymer or metal coil or braided reinforcement.

[0038] FIG. 35 shows the straight return of a balloon during deployment. In an example of a cross-section of the folded balloon, one end of the balloon at point X is fixed and the other end at point Y can move. The balloon is folded from the position shown in step 1 to the position shown in step 2 and then to the position shown in step 3. During the return folding process, points A, B, and C move towards the left side of the figure. As shown in the figure, when the balloon is wound back to the left side of the figure, point A moves from the inner diameter to the outer diameter of the balloon. In practice, the folded balloon during the preparation step is advanced into the proximal end of the fallopian tube. Further folding (extension) of the balloon (up to a total of 2-3 cm inside the fallopian tube) is achieved by further rotation of the drive wheel 204. The balloon 130 is then deflated by releasing the pressure in the inflation device. The balloon 130 can then be withdrawn from the fallopian tube. Since the fallopian tube is a potential space, the fallopian tube tissue collapses around the balloon. Since the balloon fills the fallopian tube, the surface area of the balloon is equal to the inner surface area of the fallopian tube. This matching surface area optimizes the collection of tissue from the inner surface of the fallopian tube.

[0039] To further optimize tissue collection, it is often beneficial to add wrinkles to the surface of the balloon. When the balloon deflates and forms multiple edges, wrinkles occur, and these wrinkles also assist in cell collection. These edges function in a similar manner to the edges of the curette of an approved U-scope device and the jaws of an approved biopsy forceps device. Similar to these features of the approved devices, the edges formed by the wrinkled loops concentrate the contact force for collecting cells onto the anatomical wall. However, since the collection surface is a polymer balloon, contact with endothelial cells is less traumatic than the stainless-steel contact surface of prior art diagnostic devices. The non-traumatic nature of the wrinkles on the balloon for collecting cell tissue allows for repeated inflation / deflation of the balloon inside the fallopian tube and enables the cells to be freely scraped off. The balloon deployment device of the present invention is then removed from the working channel of the hysteroscope and from the patient. Once the device is removed from the patient, the balloon can be immersed in a cell preservative and the cells can be removed from the balloon by stirring and agitating them. As a variant, both the balloon and the sheath can be detached and placed in a cytological preservative. In a particular embodiment, when the balloon is deflated and removed, the sheath may extend over and deploy over the balloon to protect the tissue sample present on the balloon surface.

[0040] FIG. 24 is a schematic cross-sectional view showing a sheathed retractable balloon tip catheter 160' according to an embodiment of the present invention. The retractable balloon tip catheter 160' is configured to have a superelastic push rod 175 and a helical carrier 176, which eliminates the need to extend the push rod backward along the entire length of the push rod. The push rod 175 is made of a superelastic material such as Nitinol (nickel-titanium compound) wire. In this case, the length of the push rod 175 is preferably wound multiple times inside a tubular helical carrier 176 made of polyethylene or polytetrafluoroethylene (Teflon (registered trademark)). The outer diameter of the helix of the helical carrier 176 is preferably about 8 cm, providing a more compact proximal actuation length. The plastic helical carrier 176 is preferably attached to the proximal Tuohy-Borst fitting 136 on the catheter using a flexible strap 177 made of a plastic or silicone rubber material. In a particular embodiment, the superelastic push rod 175 has a diameter of about 0.025" (0.635 mm), and it is difficult to grip this wire and push it forward through the Tuohy-Borst seal 136. Therefore, a freely sliding sleeve is added over the push rod 175, providing an excellent gripping portion for advancing the push rod 175 when the flexible grip 178 is compressed between the thumb and index finger. The flexible grip 178 is preferably an elliptical cross-sectional frame made of polyvinyl chloride, silicone rubber, or a similar flexible compound, with inner dimensions of about 2 cm in length, 1 cm in width, and 3 mm in height, and having a wall thickness of about 2 mm. The holes in the proximal and distal surfaces of the grip are slots that align with the push rod 175.

[0041] FIG. 25 is a schematic side view showing an embodiment of the present invention of a sheathed retractable balloon tip catheter 200 configured to have a handle 202. The handle 202 has a drive wheel 204, and the drive wheel 204 advances and retracts a push wire 206 that linearly returns the folding of the balloon 130 (gradually extends so that the inside becomes the outside). The drive wheel 204 is preferably made of plastic, for example, ABS. The outer edge of the drive wheel 204 preferably has notches that facilitate gripping of the drive wheel 204 during operation of the catheter 200. The upper surface of the drive wheel 204 has a molded arrow, and the arrow preferably indicates the correct direction of rotation to return the folding of the balloon. The opposite side of the drive wheel 204 has a square boss, and the square boss is preferably inserted into a drive gear.

[0042] The catheter 200 holds the balloon 130 in a shaft 210 (preferably made of a stainless steel tube and a nylon tube), a sheath 212, and a sheath knob 214. The handle 202 also has an extension tube 216 attached to a luer fitting 218 of the handle body. To enable the advancement of the balloon, the balloon 130 and the shaft 210 are pressurized by an inflation device (for example, the inflation device 172 of FIG. 23C) attached to the extension tube 216. Once the catheter device 200 is pressurized, the user advances the push wire 206 by rotating the drive wheel 204.

[0043] FIG. 26A is a cross-sectional view of the handle portion of FIG. 25, and FIG. 26B is a detailed view showing the internal handle gear mechanism 220. The drive wheel 204 has a square boss (not shown) inserted into the square hole 222 of the drive gear 224. When the drive wheel 204 is rotated clockwise, the square boss rotates the drive gear 224. The drive gear 224 engages with the idler gear 226 and the first gear 228, rotating these gears. Similarly, the idler gear 226 rotates the second gear 230 and thereby the third gear 232. The push wire 206 moves between and over the rubber transmission surfaces between each of the four large gears (224, 228, 230, 232) and moves as the balloon 130 is advanced as shown in FIG. 26B. The balloon 130 advances until the proximal end of the push wire 206 passes between the drive gear 224 and the first gear 228. The internal handle gear mechanism 220 enables precise, accurate, and controlled movement for the deployment and retraction of the balloon 130.

[0044] A series of steps for entering and traversing the fallopian tube will be described with reference to the embodiment of FIG. 23A. When it is desired for the 15 mm long folded balloon 130 to cross or pass through the uterotubal junction, the outer plastic sheath 162 is positioned near and not entering the proximal opening of the fallopian tube. The outer plastic sheath 162 supports the 15 mm long folded balloon 130 until it enters the proximal opening. The short length of the pressurized folded balloon 130 extending from the supporting outer plastic sheath 162 has sufficient longitudinal strength to be manually advanced through the uterotubal junction, whereas the unsupported 15 mm long folded balloon 130 does not have sufficient rigidity on its own and will bend if an attempt is made to advance it through the proximal opening and the uterotubal junction.

[0045] The sheath 162 has an outer diameter of 5 Fr (1.59 mm), and the proximal end of the sheath 162 is attached to a male Luer lock fitting 164 using a Tuohy - Borst seal 136 connector. The Tuohy - Borst adapter is a medical device used to form a seal between devices and attach a catheter to various other devices. The Tuohy - Borst seal 136 is tightened to have a slip fit with a catheter or cannula that holds the sheath 162 in place, thereby covering the folded balloon tip. The male Luer lock fitting 164, if present, preferably engages with the female Luer lock fitting of the working channel of the hysteroscope. When these Luer fittings are connected, the distal end of the outer sheath projects approximately 2 - 3 cm from the distal end of the hysteroscope. Also, the outer sheath protects a folded balloon tip of 1.5 cm in length from being damaged when advancing a catheter or cannula through the working channel of the metal hysteroscope. A stainless - steel tube with an outer diameter of 0.050” (1.27 mm) and a wall thickness of 0.004” (0.0102 mm) provides sufficient rigidity to prevent torsion of the portion that projects from the proximal end of the working channel of the hysteroscope and is thus desirable for the inner cannula 126.

[0046] FIG. 23C is a view of the sheathed retractable balloon tip catheter 160 of FIG. 23A according to an embodiment of the present invention having a high-pressure tube reservoir 168 and an inflator 172. Pressurization of the balloon 130 using fluid injection may be performed using a threaded syringe device, which is generally known as a deflation device as well as an inflator 172. Rotation of the threaded plunger shaft by a releasable lock increases and maintains the pressure within the inflator 172, and a pressure gauge 174 provided in the inflator 172 enables control of the input pressure. In a particular embodiment of the sheathed retractable balloon tip catheter 160, single-handed operation of the device is enabled. A high-pressure tube 168 of a predetermined length is added between the inflator 172 and the inflation port 166 on the device. The high-pressure tube 168 can be constructed of a polymer such as polyurethane or polyvinyl chloride (PVC), with or without a metal coil or braided reinforcement. The pressure tube 168 has a certain inherent elasticity, while the retractable balloon is generally inelastic. When the balloon 130 is fully pressurized, the pressure tube 168 contributes liquid volume to the system. A small amount of fluid is present in the retractable balloon, and this volume is further subtracted by only the volume occupied by the push rod 134 (which moves into the balloon 130 when returning the fold). The resulting volume of the retractable balloon is small compared to the larger volume of the pressure tube 168, such that when the sheathed retractable balloon tip catheter 160 is pressurized, the balloon 13 can return its full-length fold without significant pressure drop. A stopcock 170 between the pressure tube 168 and the inflator 172 can be closed after pressurization, and the heavy inflator 172 can be removed from the test field prior to insertion and return of the fold of the balloon 130. A non-intrusive single-operator procedure is the result of the embodiment design shown in FIG. 23C.

[0047] As described above with respect to FIGS. 23A-23C, the retractable balloon 130 extends distally from the distal end of the catheter by an overall distance of about 7 cm to pass through the entire length of the fallopian tube. The retractable balloon 130 assumes a donut shape when it exits the catheter tip, and the retractable portion has a double-wall configuration. Thus, the push rod 134 must advance a distance of 14 cm to create a 7 cm long retractable balloon. This length of push rod initially extends rearwardly from the proximal end of the catheter 126, directly towards the operator's face, which makes its use cumbersome. Also, this length of push rod 314 is susceptible to contamination of the sterilized device because the proximal end of the long push rod may come into contact with the physician's face or surgical mask during use. Therefore, it is desirable to provide a push rod system that does not need to extend its entire length rearwardly. The superelastic push rod and carrier design of FIG. 24, and the sheathed retractable balloon tip catheter 200 configured to have the handle 202 of FIG. 25, act to store the push rod and avoid the need to extend the push rod rearwardly towards the user.

[0048] FIG. 27 is a schematic cross-sectional side view showing a folded balloon tip catheter 180 according to an embodiment of the present invention having a thin-walled tube 182, the thin-walled tube 182 having a diameter smaller than the inflated diameter of the folded balloon 130 for insertion into the patient's uterotubal junction. The thin-walled tube 182 straightens a portion of the balloon tip 163. The thin-walled tube 182 preferably has a wall thickness of about 0.0005” to 0.001” (about 0.0127 mm to 0.0254 mm) and preferably extends 1.5 cm distally of the tip of the cannula. The thin-walled tube extension 182 supports the balloon 130 and keeps the balloon tip 163 straight, but because the diameter of the thin-walled tube is smaller than the balloon diameter, it allows the balloon 130 to retain flexibility and compressibility, which are the properties necessary to advance the balloon 130 through the uterotubal junction. In a particular embodiment, the outer diameter of the balloon is 0.04” (1 mm) and has an inner tube with an outer diameter of 0.033” (0.0762 mm), a wall thickness of 0.001” (0.0254 mm), and a length of 1.5 cm to support and straighten the balloon.

[0049] FIG. 28 is a schematic cross-sectional side view showing a folded balloon tip catheter 190 according to an embodiment of the present invention having one or more flexible plastic monofilament strands 192, the one or more flexible plastic monofilament strands 192 being attached to the distal end of the cannula 126 and extending into the folded balloon tip 163, thereby supporting and keeping the tip straight for insertion into the patient's uterotubal junction. In a particular embodiment, the one or more flexible plastic monofilament strands 192 extend 1.5 cm into the balloon tip 163. The monofilament is preferably formed of nylon, polypropylene, or other flexible plastic material. The monofilament strand preferably has a diameter of about 0.006” to 0.012” (about 0.1524 mm to 0.3048 mm). In a particular embodiment, the outer diameter of the balloon is 0.033” (0.8 mm) and has a nylon monofilament with a diameter of 0.008” (0.2 mm) inside the 1.5 cm long folded balloon tip.

[0050] Figures 29A - 29C are a series of side perspective views of an operable balloon tip 252 for a balloon catheter 250 that is refolded using a guide wire according to an embodiment of the present invention. As shown in Figure 29A, the operable balloon tip 252 is controlled by a right - hand guide wire 254 and a left - hand guide wire 256. In Figure 29B, pulling the right - hand guide wire 254 (as indicated by the arrow) directs the balloon 202 in the right - hand direction. Conversely, in Figure 29C, pulling the left - hand guide wire 256 (as indicated by the arrow) directs the balloon 202 in the left - hand direction. It should be noted that in addition to the movement in the X - Y plane achieved by a pair of guide wires as shown, another guide wire may be added to enable movement in the Z - plane.

[0051] Figure 30 is a side perspective view of a balloon catheter 260 according to an embodiment of the present invention having a smaller - diameter lead balloon tip 262 at the distal end of the refolded balloon 130. The smaller - diameter lead balloon tip 262 is sized to gradually expand an opening at a stenosis indicated by the patient's uterotubal junction, is flexible, and has an edge that is not sharp so as not to puncture the wall of the uterotubal junction.

[0052] Figure 31 is a side perspective view of a balloon catheter 270 according to an embodiment of the present invention having a flexible guide wire 272 at the tip of the balloon 130. The flexible guide wire guides the balloon catheter 220 through the patient's uterotubal junction.

[0053] In an embodiment of the refolded balloon catheter of the present invention, a portion of the refolded balloon may be treated with a fluoropolymer, silicone, and similar material coatings that lubricate the surface of the lead portion of an embodiment of the balloon catheter that enters the stenotic portion of the fallopian tube.

[0054] Figure 32 is a partial side perspective view of the striped balloon 130S according to an embodiment of the present invention, in a state before folding the striped balloon 130S into the catheter or cannula of FIG. 32. The mark 131 on the balloon constitutes a visual feedback indicator of the progress of folding of the balloon. In a particular embodiment, the mark 131 is about 1 mm wide and may be spaced at a pitch of about 1 cm along the entire length of the balloon 130S. The spacing of variations of strips or other visual markers on the balloon may be relatively close to each other for finer position feedback or relatively far apart for gross feedback. Other visual markers of the folded length include sinusoidal marks having a known period length. It should also be recognized that the length marks include a plurality of segments of different colors of known lengths.

[0055] FIG. 33 is a schematic cross-sectional view showing a sheathed, foldable balloon tip catheter 280 according to an embodiment of the present invention having a striped balloon 130C. As shown in FIG. 33, the mark 131 of the folded balloon 130S with stripes is combined with the transparent distal portion 167 of the cannula or catheter 126 to provide visual feedback of the folding of the balloon. In certain embodiments, the mark 131 may be a pad printed or marked with a highly visible, non-fading marker, about 1 mm wide and spaced at about 1 cm pitch along the entire length of the balloon. Pad printing (also called tampography) is a printing method that can transfer a two-dimensional image onto a three-dimensional object. Instead of or in addition to the mark 131 on the surface of the balloon 130S, other patterns may be used. For example, the marks 131 on the balloon 130S may be spaced 10 cm apart and dots may be added at each remaining interval between the marks. When the push rod has to be advanced 10 cm, corresponding to a 5 cm fold of the balloon length, each mark 131 visible within the transparent distal portion 167 indicates a successful 5 cm fold of the balloon length. Marks of various thicknesses, different colors, and different numbers of marks may be used in the same manner as described for the combination of stripes and dots. In certain embodiments, color-coded portions may be added to the balloon to indicate the degree of folding of the balloon.

[0056] An additional embodiment of the present invention for a feedback marker that allows a physician outside the patient's body to visually observe the degree of forward folding of the balloon involves the use of a thread with knots or stitches that are spaced at known increments to provide tactile feedback on the progression of the balloon fold. The knots or stitches may be radiopaque. The thread may have color-coded regions for providing feedback to the operator. FIG. 34 shows a thread 140 having a series of knots or stitches 142 according to an embodiment of the present invention. The balloon 130 may be transparent to enhance the visibility of the thread, knots, or stitches. In certain embodiments, the knots or stitches may form an additional cell collection surface.

[0057] A further feedback mechanism of the present invention includes ultrasonic saline-air marking and a sine wave pattern for the balloon, and the distance between the maximum values of the sine wave determines the pitch of the balloon fold.

[0058] Any patent document or publication referred to herein is incorporated herein by reference as if each individual publication were specifically and individually indicated to be incorporated by reference. The foregoing description is an example of a particular embodiment of the present invention and is not intended to be limiting in its practice.

Explanation of Signs

[0059] 1 Fallopian tube 10 Introduction catheter (tube positionable relative to the fallopian tube) 12 Non-elastic sleeve (balloon) 14 Elastic balloon (balloon) 202 Handle 204 Driving wheel 206 Push wire 220 Internal handle gear mechanism (actuator) 222 Driving gear (first gear) 226 Idle gear 228, 230, 232 First gear to third gear (second gear to fourth gear)

Claims

**Claim 1** A catheter for fallopian tube diagnosis, comprising a tube having a distal end and positionable relative to the fallopian tube, and a balloon having a proximal end and a distal end, the balloon being coupled to the distal end of the tube at the proximal end of the balloon and being movable between a folded-back first position and an unfolded second position, whereby the balloon is extendable to the unfolded second position within the fallopian tube, further having at least one of a series of knotted threads or sutures on the outer surface of the balloon in the unfolded second position, the knotted threads or sutures being configured to collect contacting cells, further a push wire attached to the balloon, and an actuator for controlling the advancement of the push wire to return the balloon to its folded-back position in a controlled manner upon pressurization, and a hysteroscope. A catheter having these components **Claim 2** The catheter according to claim 1, further comprising a pressurized fluid source selectively communicating with the balloon. **Claim 3** The catheter according to claim 1, further comprising a drive wheel mechanically coupled to the gear of the actuator. **Claim 4** The drive wheel includes a boss inserted into a first gear of the actuator, the first gear driving an idler gear and a second gear, the idler gear driving a third gear that drives a fourth gear. The catheter according to claim 3. **Claim 5** At least one of the first gear, the second gear, the third gear, and the fourth gear has a rubber transmission surface for actuating the push wire, the push wire being positioned between the first gear and the second gear and between the third gear and the fourth gear. The catheter according to claim 4. **Claim 6** The catheter according to claim 1, further comprising a handle. **Claim 7** When the balloon is deflated, a series of wrinkles are formed on the surface of the balloon, creating a plurality of edges for collecting cells. The catheter according to claim 1. **Claim 8** The catheter according to claim 1, further comprising a sheath coaxial with the tube, the sheath extending outwardly from the distal end and covering a first length portion of the folded-back balloon. **Claim 9** Furthermore, it has a thin-walled tube encapsulated by the first length portion of the balloon that extends outward and is folded back from the distal end portion, and the thin-walled tube supports the first length portion to make it straight. The catheter according to claim 8.

10. Furthermore, it has a feedback mechanism for measuring the return of the forward fold of the balloon. The catheter according to claim 1.

11. The feedback mechanism includes visual markers on the balloon, and the markers are spaced at a predetermined pitch along the balloon or have different colors. The catheter according to claim 10.

12. The knot or suture is radiopaque. The catheter according to claim 1.

13. Furthermore, it has a small-diameter lead balloon tip on the distal end portion of the balloon in the second position where the fold is returned. The catheter according to claim 1.

14. Furthermore, for entry into the stenotic portion of the patient, it has a fluoropolymer or silicone coating that smoothens the forward portion of the catheter. The catheter according to claim 1.

Images