WO2010118325A2 - Method for cryospray ablation in reproductive tissues - Google Patents

Abstract

Methods for treating reproductive tissues of a patient are described. A cryospray surgical apparatus is used to apply a cryogen to at least one area of the reproductive tissue, thereby treating the targeted tissue. Treatment may include ablation of the target tissue, or the initiation of a desired biological response or the delivery of therapeutics to the reproductive tract.

Description

METHOD FOR CRYOSPRAY ABLATION IN REPRODUCTIVE TISSUES

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to United States Provisional Application for Patent Serial No. 61/168,367 filed April 10, 2009, the entire contents of which are specifically incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The invention relates to methods of treating conditions of reproductive tissues.

BACKGROUND OF THE INVENTION

[0003] The reproductive organs are among the most common sites of cancer in women. Reproductive cancers account for more than 73,000 new cases and approximately 23,000 deaths in the United States, each year. The most common cancer in the female reproductive system is carcinoma, which can be present in the endometrium, cervix, ovary, vulva, vagina or fallopian tubes. Endometrial carcinoma is the fourth most common cause of cancer in woman, behind breast, colorectal, and lung cancers. Approximately 40,000 new cases of endometrial cancer are diagnosed each year. Cervical carcinoma, which can present as either in situ or invasive squamous cell carcinoma, is the second most common malignancy of the female reproductive tract, usually effecting women aged 40-55. Each year approximately 12,000 new cases of cervical cancer are diagnosed.

[0004] While estimates vary, endometriosis is commonly found in 10-15% of all women between the ages of 25 and 44 years old. Endometriosis is a non-malignant disease in which functioning endometrial tissue is present in sites outside of the uterine cavity, generally as a result of retrograde flow of menstrual fluid that transports endometrial cells that ultimately transplant in ectopic sites. The most common sites for endometriosis include the ovaries; fallopian tubes; the back and front of the uterus, as well as the posterior and anterior cul-de- sac of the uterus; the uterine ligaments; and the pelvic and back wall. Less commonly, endometriosis can be found on the intestines, diaphragm, urinary bladder, ureters, cervix and vagina. Endometriosis commonly results in acute and/or chronic pain, infertility and pelvic inflammatory disease. Treatment of endometriosis typically involves the administration of agents that suppress ovarian function, as well as surgery, which may include a total hysterectomy in severe cases. [0005] Neoplasms of trophoblastic origin are also found following intra- or extrauterine pregnancy. These neoplasms typically present as hydatidiform moles. Persistent trophoblastic disease (PTD) is a local invasion of the myometrium by the villi of the hydatidiform, while metastatic trophoblastic disease (MTD) is an invasive, usually widely metastatic, tumor composed only of syncytiotrophoblastic and cytotrophoblastic elements. Approximately 1/2000 pregnancies result in the presence of a hydatidiform mole. For unknown reasons the incidence in Asian countries approaches 1/200 pregnancies. Treatment of hydatidiform moles generally involves curettage of the uterine contents, following oxytocin stimulation. Treatment for PTD and MTD generally involves chemotherapy and hysterectomy in cases that are unresponsive to chemotherapy.

[0006] Treatment for these conditions generally require removal of unwanted or damaged tissue, often by surgery, which often involves either dilation and curettage (D&C) or total hysterectomy, depending on severity. Over 625,000 hysterectomies are performed each year in the United States alone. Approximately 12.3% of all US women between the ages of 40 and 44 have had a hysterectomy. 89.5% of these procedures were performed for medical reasons. Common complications associated with the performance of a hysterectomy include blood clots, infection, excessive bleeding and adverse reactions to the anesthesia. In addition, significant longer term psychological and physical affects have been reported, including severe depression and loss of sexual drive. If the ovaries are removed along with the uterus prior to menopause, there is an increased risk of osteoporosis and heart disease as well.

[0007] The most common procedure performed for the removal of unwanted tissue is the D&C, in which the cervix of the uterus is expanded (dilated) so that the uterine lining (endometrium) can be removed with a spoon-shaped instrument called a curet or curette. This can be done for diagnostic or therapeutic purposes. The most common severe complication in the performance of a D&C is perforation of the uterus with either the dilators or the curette. Injury to the cervix is another possible complication. Other complications include bleeding, infection and adverse reactions to the anesthesia.

[0008] Other common approaches for treating or removing lesions or cancer include surgical resection, radiotherapy, and chemotherapy, all of which are associated with significant morbidity and mortality. [0009] New surgical alternatives for removal of tissue are needed that are associated with less severe adverse events and result in better outcomes, thereby decreasing the need for additional, more radical surgery. The methods described in this patent meet such a need.

[0010] In addition to the presence of unwanted or medically dangerous tissue, common conditions affecting the female reproductive include abnormal menses or abnormal uterine bleeding. Abnormal menstrual bleeding can be classified as either metorhagia/hypermenorrhea (increase menstrual bleeding), menorrhagia (increase menstrual duration), metrorrhagia (intermenstrual or nonmenstrual bleeding) and postmenopausal bleeding. Bleeding can also occur secondary to trauma or other tissue injury.

[0011] Treatment of conditions involving abnormal menstrual bleeding often involve the use of endometrial ablation. Endometrial ablation can be performed by a variety of methods, including thermal ablation, rollerball endometrial ablation (REA), hysteroscopy or cryoablation. Thermal ablation, REA and hysteroscopy typically involve the ablation of endometrial tissue by burning or cautery, followed by surgical removal of the ablated tissue.

[0012] Endometrial cryoablation involves the ablation of endometrial tissue using cold temperatures. Current methods of performing cryoablation involve the use of a cryoprobe or cryoballoon, which comes into direct contact with the endometrial surface and freezes, or significantly reduces the temperature of, the tissue. These methods include the HerOption system, marketed by American Medical Systems, and the cryoballoon procedure described in U.S. Patent Application No. 11/829,186. Disadvantages of both systems include the fact that tissue adheres to the probe and/or balloon during the freezing step. Therefore, it is necessary to heat the probe or balloon prior to removal. Insufficient heating will lead to tissue damage as tissue will be torn from the uterus as the probe or balloon is removed. In addition, the probe of the HerOption system has a diameter of 2-5 mm, and multiple freezing/heating cycles must be employed in order to ablate all endometrial tissue.

[0013] Thus the medical industry would benefit from a new treatment procedures for performing cryotherapeutic and cryosurgical procedures on reproductive tissues.

SUMMARY OF THE INVENTION

[0014] The invention relates to methods for treating the reproductive tissues and organs of a patient. The treatment is performed using a cryospray surgical apparatus. In one embodiment, the cryogen may be applied to an affected area of the tissue, thereby ablating or otherwise damaging the targeted tissue. Alternatively, tissue may be ablated by using cryogen to create an isotherm in proximity to the tissue in need of ablation.

[0015] In another embodiment, the cryogen may be applied to the affected area of the tissue, thereby providing the desired therapeutic response. Alternatively, tissue may be treated by using cryogen to create an isotherm in proximity to the tissue in need of treatment. This therapeutic response may include hemostasis or induction of a biological response (including immune response).

[0016] Cryospray treatment may be performed with or without the use of a visualization aid such as an endoscope or hysteroscope.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] For the purpose of illustrating the invention, there is shown in the drawings a form which is presently preferred; it being understood, that this invention is not limited to the precise arrangements and instrumentalities shown.

[0018] Fig. IA depicts an endoscope (i.e., a hysteroscope) that may be used in the practice of some embodiments of the present invention.

[0019] Fig. IB is an enlarged schematic view of Fig. IA and shows the distal end of the endoscope.

[0020] Fig. 2A depicts a close-up of the distal end of an endoscope, light source, camera, extra lumen, and lumen with an inserted catheter having an opening for releasing cryogen spray.

[0021] Fig. 2B depicts a close-up of the distal end of an endoscope, light source, camera, extra lumen, and lumen with an inserted catheter having a lateral opening for emitting directional cryogen spray.

[0022] Fig. 2C depicts a close-up of the distal end of an endoscope, light source, camera, extra lumen, and lumen with an inserted catheter having a laterally-disposed, cone-shaped structure for directing cryogen spray.

[0023] Fig. 3 is a schematic view of an apparatus for use in cryosurgery. [0024] Fig. 4 is a schematic view of an apparatus for use in cryosurgery. [0025] Fig. 5 depicts the structure of a heated catheter. DETAILED DESCRIPTION

[0026] It will be appreciated that the following description is intended to refer to embodiments of a cryosurgical apparatus for use in the methods of the present invention and is not intended to define or limit the invention, other than in the appended claims.

[0027] The invention relates to methods of treating or preventing abnormal or pathogenic conditions in the reproductive tissues. As used herein, the term "reproductive tissues" or "tissues of the reproductive system" includes those tissues involved in mammalian reproduction including, but not limited to, the labia, clitoris, vagina, cervix, uterus, fallopian tubes, ovaries, penis, urethra, testicles, vas deferens, scrotum, epididymis, seminal vesicle, or prostate.

[0028] Cryospray ablation of reproductive tissue can be used to destroy and ultimately remove unwanted or medically dangerous tissues. Tissues that may be ablated by cryospray ablation include malignant tumors and/or lesions, masses that are suspected of being malignant; or benign tissues, tumors or lesions.

[0029] In one embodiment, cryospray treatment may be used to remove malignant tissues of the reproductive system. For example, malignant tissues may include, but are not limited to, carcinomas of the uterus, endometrium, cervix, vulva, vagina, ovaries or fallopian tubes. Ablation of these malignant tissues may be accomplished by spraying cryogen on the tissue using the apparatuses and methods described herein. Alternatively, tissue may be ablated by using cryogen to create an isotherm in proximity to the tissue in need of ablation.

[0030] In other embodiments, cryospray treatment may be used to treat patients with trophoblastic disease, including those patients with hydatidiform moles. Cryospray treatment may involve the ablation of the affected tissue, including the hydatidiform mole(s).

[0031] Cryospray treatment of tissues suspected of being malignant may be performed with or without additional treatments or procedures. For example, cryospray ablation of suspected malignant tissues may be performed in combination with chemotherapy, radiotherapy or hormone therapy. It is also contemplated that the cryospray may be supplemented with and/or used in conjunction with one or more additives. In another embodiment, cryospray treatment may be done in conjunction with oxytocin stimulation of the uterus. In yet another embodiment, said cryospray treatment may be done in conjunction with chemotherapy, radiotherapy or hormone therapy. [0032] In another embodiment, cryospray treatment may be used to remove tissues that are suspected of being malignant. For example, tissues may include, but are not limited to, the uterus, endometrium, cervix, vulva, vagina, ovaries or fallopian tubes. Ablation of these tissues may be accomplished by spraying cryogen on the tissue using the apparatuses and methods described herein. Alternatively, tissue may be ablated by using cryogen to create an isotherm in proximity to the tissue in need of ablation.

[0033] Cryospray treatment of tissues suspected of being malignant may be performed with or without additional treatments or procedures. For example, cryospray ablation of suspected malignant tissues may be performed in combination with chemotherapy, radiotherapy or hormone therapy. It is also contemplated that the cryospray may be supplemented with and/or used in conjunction with one or more additives.

[0034] In another embodiment, cryospray treatment may be used to remove benign tissues. Tissues may include, but are not limited to, the uterus, endometrium, cervix, vulva, vagina, ovaries or fallopian tubes. Ablation of these tissues may be accomplished by spraying cryogen on the tissue using the apparatuses and methods described herein. Alternatively, tissue may be ablated by using cryogen to create an isotherm in proximity to the tissue in need of ablation. In some embodiments, methods of ablating benign tissue may comprise blocking the fallopian tubes. This may prevent or reduce the amount of gas that exits the uterus through the fallopian tubes.

[0035] In another embodiment, cryospray ablation can be used to remove endometrial tissue either from the uterus, or from sites outside the uterus. For example, the methods and devices of the current invention may be used to perform a dilation and curettage (D&C) by spraying the endometrial tissue within the uterus until said endometrial tissue is ablated ("cryo- D&C"). It is also contemplated that the cryospray may be supplemented with and/or used in conjunction with one or more additives. Alternatively, the cryospray ablation treatment may be done in conjunction with one or more other treatments or procedures. In one embodiment, a cryo-D&C is performed in conjunction with Oxytocin stimulation of the uterus to facilitate removal of ablated tissue.

[0036] Cryospray ablation can also be used to treat endometriosis by ablating the endometrial tissue located outside the uterus. Ablation of endometrial tissues may be accomplished by spraying cryogen on the tissue using the apparatuses and methods described herein. Alternatively, endometrial tissue may be ablated by using cryogen to create an isotherm in proximity to the tissue in need of ablation. Cryospray ablation therapy may be performed using various visualization techniques, as described herein, including endoscopy or laparoscopy.

[0037] In another embodiment, cryospray treatment may be used to induce or modify a biological response in the target tissue. Treatment of these tissues may be accomplished by spraying cryogen on the tissue using the apparatuses and methods described herein. Alternatively, tissue may be treated by using cryogen to create an isotherm in proximity to the tissue in need of treatment. In one embodiment, cryospray treatment may be used to induce an immune response in the reproductive tissues. In another embodiment, cryospray treatment may be used to induce stricture formation or cartilage generation.

[0038] In another embodiment, cryospray therapy may be used to treat reproductive tissues in patients with abnormal bleeding. Such abnormal bleeding may be abnormal menstrual bleeding. Such abnormal menstrual bleeding may include metrorrhagia/hypermenorrhea (increase menstrual bleeding), menorrhagia (increase menstrual duration), metrorrhagia (intermenstrual or nonmenstrual bleeding) and postmenopausal bleeding. Bleeding can also occur secondary to trauma or other tissue injury.

[0039] In one embodiment, treatment of patients with abnormal menstrual bleeding may be accomplished by cryospray ablation of the endometrial tissue. Cryospray ablation of the endometrial tissue may be accomplished by spraying cryogen directly on the endometrium for a time sufficient to ablate the desired tissue. Alternatively, cryogen may be used to create an isotherm in proximity to the endometrial tissue in need of ablation.

[0040] In another embodiment cryospray treatment may be used to treat tissues afflicted by infectious diseases. Said infectious diseases may include, but are not limited to, bacterial, viral, or fungal infections. Said cryospray treatment may involve the ablation of the infected tissue by spraying cryogen on the tissue using the apparatuses and methods described herein. Alternatively, tissue may be treated by using cryogen to create an isotherm in proximity to the tissue in need of treatment.

[0041] In another embodiment of the invention, the fallopian tubes may be blocked during the cryospray treatment to prevent the flow of gas through the fallopian tubes and into the abdomen. In one embodiment, such blocking may prevent or lessen contact of cryogen with the ovaries, or prevent damages to the ovaries from isotherms generated by the cryospray. Devices used to block the fallopian tubes include, but are not limited to, balloons, plugs, dams, or sheets. In one embodiment, said blocking devices may be insulated to decrease the amount of freezing of tissues that are not the target of the cryospray treatment. In another embodiment, said blocking devices may be attached to the cryospray apparatus.

[0042] It is also contemplated that the cryospray may be supplemented with and/or used in conjunction with one or more additives. For example, cryospray may be used as a means of delivering therapeutic agents to the target tissues. In some embodiments of the invention, cryospray may be used to stimulate or enhance fertility directly or indirectly. For example, fertility agents such as Gonadotropin releasing hormone, Estrogen antagonists or Gonadotropins, can be delivered with the cryospray. Other agents include, but are not limited to, Clomid or Serophene (clomiphene citrate). In some embodiments, agents may comprise injectable and/or sprayable hormones. Suitable examples of hormones include, but are not limited to, Human Chorionic Gonadotropin (hCG) (e.g., Pregnyl, Novarel, Ovidrel, and Profasi.), which may be used in combination with other fertility drugs to trigger the ovaries to release the mature egg or eggs; Follicle Stimulating Hormone (FSH) (e.g., Follistim, Fertinex, Bravelle, and Gonal-F); Human Menopausal Gonadotropin (hMG) (e.g., Pergonal, Repronex, and Metrodin), which may be a combination of FSH and luteinizing hormone (LH); Gonadotropin Releasing Hormone (Gn-RH) (e.g., Factrel and Lutrepulse), which may be used to stimulate the release of FSH and LH from the pituitary gland; Gonadotropin Releasing Hormone Agonist (GnRH agonist) (e.g., Lupron, Zoladex, and Synarel); Gonadotropin Releasing Hormone Antagonist (GnRH antagonist) (e.g., Antagon and Cetrotide); and Antagon (ganirelix acetate), which may be used to inhibit premature ovulation in women undergoing fertility procedures.

[0043] Such additives may be mixed with the liquid nitrogen or other cryogen and simultaneously sprayed onto target tissue, or may be delivered (e.g., sprayed) separately from the cryogen before, during or after cryotherapy. Any suitable medium may be used to spray additives, for example, gases or liquids, which may be at the same temperature or at a higher or lower temperature than the target tissue. Non-limiting examples of contemplated additives include organic chemicals, agents, or compound formulations, inorganic chemicals or agents, gene therapy agents including but are not limited to, viruses, lipids, other transfection agents or naked circularized or linear DNA, dyes or indicators, either organic or inorganic, gels, liquids, solids, gases and crystals, glues, pharmaceuticals, prodrugs, aerosols, blood, plasma, tissue or other biological products, solvents (covered under chemicals), polymers, plasticizers, and absorbable, expandable materials, nano-technology, robotics, and/or magnetized material/products. In some aspects of the invention, oxygen can also be used as a therapeutic agent. Further, diagnostic agents including, but not limited to, radiolabeled substances, haptens, priming agents, imaging agents, fluorescent agents, magnetic marker materials, contrast agents such as X-ray, ultrasound and MRI contrast enhancing agent, can be supplemented with cryospray.

[0044] Examples of diagnostic or therapeutic agents that can be delivered are pharmaceutically acceptable salt or dosage form of an antimicrobial agent (e.g., antibiotic, antiviral, anti-parasitic, antifungal, etc.), an anesthetic agent with or without a vasoconstriction agents (e.g. Xylocalne with or without Epinephrine, Tetracaine with or without epinephrine, etc.), an analgesic agent, a corticosteroid or other anti-inflammatory (e.g., an NSAID), a decongestant (e.g., vasoconstrictor), a mucous thinning agent (e.g., a mucolytic), an agent that prevents of modifies an allergic response (e.g., an antihistamine, cytokine inhibitor, leucotriene inhibitor, IgE inhibitor, immunomodulator), an allergen or another substance that causes secretion of mucous by tissues, hemostatic agents to stop bleeding, anti-proliferative agents, cytotoxic agents e.g. alcohol, biological agents such as protein molecules, stem cells, genes or gene therapy preparations, viral vectors carrying DNA, proteins or mRNA coding for important therapeutic functions or substances etc.

[0045] Some nonlimiting examples of antimicrobial agents that may be used in this invention include acyclovir, amantadine, aminoglycosides (e.g., amikacin, gentamicin and tobramycin), amoxicillin, amoxicillin/clavulanate, amphotericin B, ampicillin, ampicillin/sulbactam, atovaquone, azithromycin, cefazolin, cefepime, cefotaxime, cefotetan, cefpodoxime, ceftazidime, ceftizoxime, ceftriaxone, cefuroxime, cefuroxime axetil, cephalexin, chloramphenicol, clotrimazole, ciprofloxacin, clarithromycin, clindamycin, dapsone, dicloxacillin, doxycycline, erythromycin, fluconazole, foscarnet, ganciclovir, atifloxacin, imipenem/cilastatin, isoniazid, itraconazole, ketoconazole, metronidazole, nafcillin, nafcillin, nystatin, penicillin, penicillin G, pentamidine, piperacillin/tazobactam, rifampin, quinupristin-dalfopristin, ticarcillin/clavulanate, trimethoprim/sulfamethoxazole, valacyclovir, vancomycin, mafenide, silver sulfadiazine, mupirocin (e.g., Bactroban Nasal®, Glaxo SmithKline, Research Triangle Park, N. C), nystatin, triamcinolone/nystatin, clotrimazole/betamethasone, clotrimazole, ketoconazole, butoconazole, miconazole, tioconazole, detergent-like chemicals that disrupt or disable microbes (e.g., nonoxynol-9, octoxynol-9, benzalkonium chloride, menfegol, and N-docasanol); chemicals that block microbial attachment to target cells and/or inhibits entry of infectious pathogens (e.g., sulphated and sulponated polymers such as PC-515 (carrageenan), Pro-2000, and Dextrin 2 Sulphate); antiretroviral agents (e.g., PMPA gel) that prevent retroviruses from replicating in the cells; genetically engineered or naturally occurring antibodies that combat pathogens such as anti- viral antibodies genetically engineered from plants known as "plantibodies;" agents which change the condition of the tissue to make it hostile to the pathogen (such as substances which alter mucosal pH (e.g., Buffer Gel and Acidform), non-pathogenic or "friendly" microbes that cause the production of hydrogen peroxide or other substances that kill or inhibit the growth of pathogenic microbes (e.g., lactobacillus); antimicrobial proteins or peptides. 6] Additionally or alternatively, in some applications where it is desired to treat or prevent inflammation the substances delivered in this invention may include various steroids or other anti-inflammatory agents (e.g., nonsteroidal anti-inflammatory agents or NSAIDS), analgesic agents or antipyretic agents. For example, corticosteroids may be used, such as beclomethasone (Vancenase® or Beconase®), flunisolide (Nasalide®), fluticasone proprionate (Flonase®), triamcinolone acetonide (Nasacort®), budesonide (Rhinocort Aqua®), loterednol etabonate (Locort) and mometasone (Nasonex®). Other salt forms of the aforementioned corticosteroids may also be used. Also, other non-limiting examples of steroids that may be useable in the present invention include but are not limited to aclometasone, desonide, hydrocortisone, betamethasone, clocortolone, desoximetasone, fluocinolone, flurandrenolide, mometasone, prednicarbate; amcinonide, desoximetasone, diflorasone, fluocinolone, fluocinonide, halcinonide, clobetasol, augmented betamethasone, diflorasone, halobetasol, prednisone, dexamethasone and methylprednisolone. Other antiinflammatory, analgesic or antipyretic agents that may be used include the nonselective COX inhibitors (e.g., salicylic acid derivatives, aspirin, sodium salicylate, choline magnesium trisalicylate, salsalate, diflunisal, sulfasalazine and olsalazine; para-aminophenol derivatives such as acetaminophen; indole and indene acetic acids such as indomethacin and sulindac; heteroaryl acetic acids such as tolmetin, dicofenac and ketorolac; arylpropionic acids such as ibuprofen, naproxen, flurbiprofen, ketoprofen, fenoprofen and oxaprozin; anthranilic acids (fenamates) such as mefenamic acid and meloxicam; enolic acids such as the oxicams (piroxicam, meloxicam) and alkanones such as nabumetone) and Selective COX-2 Inhibitors (e.g., diaryl-substituted furanones such as rofecoxib; diaryl-substituted pyrazoles such as celecoxib; indole acetic acids such as etodolac and sulfonanilides such as nimesulide). [0047] Additionally or alternatively, in some applications, such as those where it is desired to treat or prevent an allergic or immune response and/or cellular proliferation, the substances delivered in this invention may include a) various cytokine inhibitors such as humanized anti- cytokine antibodies, anti-cytokine receptor antibodies, recombinant (new cell resulting from genetic recombination) antagonists, or soluble receptors; b) various leucotriene modifiers such as zafirlukast, montelukast and zileuton; c) immunoglobulin E (IgE) inhibitors such as Omalizumab (an anti-IgE monoclonal antibody formerly called rhu Mab-E25) and secretory leukocyte protease inhibitor) and d) SYK Kinase inhibitors.

[0048] Additionally or alternatively, in some applications such as those wherein it is desired to treat a tumor or cancerous lesion, the substances delivered in this invention may include antitumor agents (e.g., cancer chemotherapeutic agents, biological response modifiers, vascularization inhibitors, hormone receptor blockers, or other agents that destroy or inhibit neoplasia or tumorigenesis) such as; alkylating agents or other agents which directly kill cancer cells by attacking their DNA (e.g., cyclophosphamide, isophosphamide), nitrosoureas or other agents which kill cancer cells by inhibiting changes necessary for cellular DNA repair (e.g., carmustine (BCNU) and lomustine (CCNU)), antimetabolites and other agents that block cancer cell growth by interfering with certain cell functions, usually DNA synthesis (e.g., 6 mercaptopurine and 5-fluorouracil (5FU), antitumor antibiotics and other compounds that act by binding or intercalating DNA and preventing RNA synthesis (e.g., doxorubicin, daunorubicin, epirubicin, idarubicin, mitomycin-C and bleomycin) plant (vinca) alkaloids and other anti-tumor agents derived from plants (e.g., vincristine and vinblastine), steroid hormones, hormone inhibitors, hormone receptor antagonists and other agents which affect the growth of hormone-responsive cancers (e.g., tamoxifen, herceptin, aromatase ingibitors such as aminoglutethamide and formestane, triazole inhibitors such as letrozole and anastrazole, steroidal inhibitors such as exemestane), antiangiogenic proteins, small molecules, gene therapies and/or other agents that inhibit angiogenesis or vascularization of tumors (e.g., meth-1, meth-2, thalidomide), bevacizumab (Avastin), squalamine, endostatin, angiostatin, Angiozyme, AE-941 (Neovastat), CC-5013 (Revimid), medi-522 (Vitaxin), 2- methoxyestradiol (2ME2, Panzem), carboxyamidotriazole (CAI), combretastatin A4 prodrug (CA4P), SU6668, SUl 1248, BMS-275291, COL-3, EMD 121974, IMC-ICl 1, IM862, TNP- 470, celecoxib (Celebrex), rofecoxib (Vioxx), interferon alpha, interleukin-12 (IL- 12) or any of the compounds identified in Science Vol. 289, Pages 1197-1201 (Aug. 17, 2000) which is expressly incorporated herein by reference, biological response modifiers (e.g., interferon, bacillus calmette-guerin (BCG), monoclonal antibodies, interluken 2, granulocyte colony stimulating factor (GCSF), etc.), PGDF receptor antagonists, herceptin, asparaginase, busulphan, carboplatin, cisplatin, carmustine, chlorambucil, cytarabine, dacarbazine, etoposide, flucarbazine, fluorouracil, gemcitabine, hydroxyurea, ifosphamide, irinotecan, lomustine, melphalan, mercaptopurine, methotrexate, thioguanine, thiotepa, tomudex, topotecan, treosulfan, vinblastine, vincristine, mitoazitrone, oxaliplatin, procarbazine, streptocin, taxol, taxotere, analogs/congeners and derivatives of such compounds as well as other antitumor agents not listed here.

[0049] Additionally or alternatively, in some applications such as those where it is desired to grow new cells or to modify existing cells, the substances delivered in this invention may include cells (mucosal cells, fibroblasts, stem cells or genetically engineered cells) as well as genes and gene delivery vehicles like plasmids, adenoviral vectors or naked DNA, mRNA, etc. injected with genes that code for anti-inflammatory substances, etc., and, as mentioned above, osteoclasts that modify or soften bone when so desired, cells that participate in or effect mucogenesis, ciliagenesis or chondrogenesis etc.

[0050] In one embodiment of the invention, the method comprises delivering therapeutic agents without a cryogen (for example a non-cryogenic gas), including, but are not limited to, oxygen, room air and CO₂, wherein the reproductive tissue to be treated is not frozen upon the contact of non-cryogenic gas.

[0051] In some embodiments, the method comprises treating a target reproductive tissue, for example, a lesion and/or tissue comprising the lesion to be treated, contacting with a non- cryogenic gas for a period of time sufficient to initiate a response in and/or without freezing the lesion and/or tissue comprising the lesion. Alternatively, the lesion and/or tissue comprising the lesion to be treated may be in proximity to an isotherm having a temperature above the freezing point of the tissue for a period of time sufficient to initiate a response in and/or without freezing the lesion and/or tissue comprising the lesion.

[0052] In some embodiments, the method comprises delivering the therapeutic or diagnostic agents prior to contacting the tissue with cryogen or non-cryogenic gas, or using the cryogen or non-cryogenic gas to create an isotherm in proximity to the tissue.

[0053] In some embodiments, the method comprises delivering the therapeutic or diagnostic agents at the same time as contacting the tissue with cryogen or non-cryogenic gas, or using the cryogen or non-cryogenic gas to create an isotherm in proximity to the tissue. [0054] In some embodiments, the method comprises delivering the therapeutic or diagnostic agents after contacting the tissue with cryogen or non-cryogenic gas, or using the cryogen or non-cryogenic gas to create an isotherm in proximity to the tissue.

[0055] In some embodiments, the method comprises mixing the therapeutic or diagnostic agents with the cryogen or non-cryogenic gas prior to contacting the tissue with cryogen or non-cryogenic gas, or using the cryogen or non-cryogenic gas to create an isotherm in proximity to the tissue.

[0056] While not wishing to be bound by any particular theory, it is contemplated that delivery of an additive with cryotherapy will facilitate cellular uptake of the additive, especially by cryotreated tissue. In vitro studies investigating the delivery of chemotherapeutic agents to frozen cells demonstrated that cold increases cellular permeability and, thereby, susceptibility to a chemotherapeutic agent that does not otherwise enter cells efficiently. Mir, LM and Rubinsky, B. (2002) Treatment of cancer with cryochemotherapy. Brit J Cane 86, 1658-1660. It is, therefore, contemplated that cryospray- induced cellular permeability may preferentially facilitate the uptake of cryospray additives into treated cells rather than non-target cells.

[0057] It is also contemplated that cells that are stimulated to grow and replicate in response to cryotherapy would rapidly assimilate biomaterials from the immediate environment. Thus, cryotherapy may make these cells less selective as to the materials they incorporate and more likely to assimilate cryospray additives. Further, when cells are immediately killed by cryofrost or sent into apoptosis following exposure, an immune response can be generated. The immune response can include a cytotoxic T cell response, a humoral response or an innate response. The immune response can involve the production of cytokines, chemokines or other signaling molecules and can involve an inflammatory response. Such mechanisms may modulate the bioavailabilty or cellular uptake of an additive or the metabolism of a prodrug into its active form.

[0058] It is also contemplated that cryotherapy may be utilized to manipulate immune system responses. While not wishing to be bound by any particular theory, it is contemplated that cells critically damaged by cryospray will initiate their apoptotic machinery. These dead and dying cells may recruit immune effecter cells, such as macrophages or other phagocytes and T helper cells, to the treated site. [0059] By taking advantage of this mechanism, it is contemplated that cryotherapy may be used to initiate a targeted immune response for the treatment of disease, or to enhance or stimulate fertility. Recruiting immune cells to a site of pathology may increase the likelihood of encounter and, thus, allow the immune system to recognize a tumor cell, pathogen, or other cells that may otherwise evade the normal innate or adaptive immune system responses. Such methods may be used to treat cancer, infections, or other conditions that may benefit from an increased or targeted immune response. An inflammatory response associated with same may also beneficially effect the desired therapy. For example, inflamed tissue can be more permeable to therapeutic agents than non-inflamed tissue.

[0060] It is also contemplated that cryotherapy may be used to suppress inflammation as well as to induce a systemic immune and antimetastatic response. Cryotherapy is frequently used to treat and alleviate inflammation of other parts of the body as well as to induce a systemic immune and antimetastatic response, such as by application of ice packs to injured muscle tissue. While not wishing to be bound by any particular theory, it is contemplated that cryospray therapy may be used to cool target tissue without developing cryofrost and cellular damage or death. Alternatively, more intense cryotherapy may be used to initiate a response in and/or freeze and kill nerve endings that are sending pain signals, thereby inducing an analgesic effect. Such cryo treatment may alleviate swelling, heat, and pain of tissue caused by inflammation.

[0061] It is also contemplated that cryotherapy may have useful application in tissue transplantation. For example, early studies involving the transplant of cadaverous aorta tissue into the airway of a recipient sheep suggest that cryotherapy may be helpful in generating immune neutral tissue transplant and stimulating chondrogenesis and the growth of ciliated epithelium in the aorta tissue. While not wishing to be bound by any particular theory, it is believed that cryotherapy performed on transplanted tissue or surrounding tissue could stimulate growth of epithelial or other tissues, intercellular signaling and/or response to signals that may promote the generation of new tissues or the expression of a desired phenotype in the transplanted tissues. In some embodiments, a site into which tissue is to be transplanted is first treated with cryogen. The treatment may result in freezing of the target site. After treatment with cryogen, the tissue to be transplanted may be attached to the treated site. A period of time may be allowed to elapse between treatment and attachment.

[0062] As used herein, "endoscope" means any instrument used as a viewing system for examining an inner part of the body. Specifically, the term endoscope may include devices such as hysteroscopes, uteroscopes, metroscopes, bronchoscopes, laproscopes or other such devices as may be deemed appropriate by one of ordinary skill in the art.

[0063] The method of the present invention can be performed using a therapeutic endoscope, which may be a hysteroscope. The distal end 12 of such an endoscope 10 is shown in FIGs. 2A, 2B, and 2C, showing an imaging camera lens 14, illuminating light 16, biopsy channel (bore or lumen) 18 with the catheter 20 therein. A therapeutic endoscope can contain an additional lumen 22. The image picked up at the lens 14 can be transferred via fiber optics to a monitoring camera 25 (FIG. 3) which sends TV signals via a cable 26 to a monitor 28, where the procedure can be directly visualized by a physician or other observer. The surgeon can perform the cryosurgery on reproductive tissues with the aid of this visualization. The catheter 20 may protrude from the distal end 12 (i.e., the end first inserted into the reproductive tract) of the endoscope 10 and may extend to the proximal end 30 (closest to the operator, outside the patient) where a physician's hand Hl can guide the catheter 20. As seen in the monitor image 28 of FIG. 4, the distal end 12 of the catheter 20 may be bent at an angle.

[0064] Alternatively, if the tissue in need of cryotherapy is readily visible and accessible, the catheter may be used without a scope. In lieu of an endoscope, a guiding device for directing the distal end of the catheter towards the lesion may be used. Preferably, the guiding device helps to avoid direct contact between the tissue and catheter. Alternate non-optical guiding devices can be found in U.S. Patent Application No. 12/022,013, filed January 29, 2008, which is incorporated by reference herein in its entirety.

[0065] The catheter 20 can be coupled to a cryogen source, such as a tube extending near the bottom of a Dewar flask 32 filled with liquid nitrogen or other liquefied gas LG. As shown in Fig. 4, the Dewar flask 32 is closed and the interior space is pressurized with a small air pump 34, which may alternatively be mounted in the container lid or elsewhere. As an alternative to a cryogen source comprising a pump to achieve a desired pressure, a pre- pressurized container of liquefied gas or apparatus which causes gas to liquefy and then be directly directed to the catheter may be used. Any device capable of driving liquefied gas from the cryogen source to and through the catheter may be used.

[0066] FIG. 4 shows schematically that the proximal end of the catheter 20 can be coupled to a tube 35, by a connector such as a standard luer lock 37, and the lower end of the tube 35 is immersed in liquid nitrogen LG while the interior is pressurized by a free-running pressure pump 34 through a tube 38. A pressure gauge 40, or alternatively a safety valve with a preset opening pressure (not shown) may be included. The pressure is selected so as to permit adequate spray from the distal end of the catheter 20. The interior of the Dewar flask 32 is vented through a vent tube 42 which can be opened and closed by a valve operated by the physician's hand H2. FIG. 4 shows the thumb obstructing the end of the vent tube 42. When the vent is closed, pressure builds up in the Dewar flask 32 and the liquefied gas is pumped through the tube 35 to catheter 20.

[0067] The vent tube 42 can be left open until the physician has positioned the catheter near the tissue to be treated, as guided by the hand Hl and confirmed by viewing the monitor 28. The vent 42 is then closed and liquefied gas is pushed into the proximal end of the catheter 20 at the luer lock 37.

[0068] The apparatus shown in Figures 3 and 4 can also be used with the methods of the present invention and is more fully described in U.S. Pat. No. 7,025,762 to Johnston et al., which is hereby incorporated by reference. Other apparatus capable of delivering liquid cryogen to a catheter, particularly low temperature, low pressure cryogen, may also be employed.

[0069] As shown in Figure 4, an electronic monitoring and recording system 90 may also be used with the apparatus during cryosurgery and is described in US Patent 7,025,762. The electronic components of the system may comprise a control box 99, temperature sensor or probe 92 and timer 96. Also connected to the monitoring and recording system may be a foot-pedal 86 for actuating the solenoid and a recording console. An electric power cord can run from solenoid to the control box. The electronic monitoring and recording system may record the times at which cryofrost starts and ends. Temperature in the treatment space may also be recorded for the cryosurgery at pre-selected time increments. This recordation allows for better data acquisition and documentation. The electronic console can be preprogrammed to be patient specific.

[0070] Figure 4 also depicts a gas supply system 70 comprising a tank 72 equipped with valves and gauges. The tank 72 is equipped with a head gas valve 77 for relieving head pressure and a liquid nitrogen valve 78 which is opened to allow liquid nitrogen to flow to the solenoid valve 80 and then to catheter 20. Pressure building tube 74 allows circulation of cryogen outside of the tank to increase pressure in the tank by heating the cryogen. The system may also comprise a bleeder valve 88. [0071] When performing cryotherapy procedures, the cryogen spray can be conducted in such a manner as to allow constant direct visualization by the physician of the targeted tissue treatment as it occurs. The treatment may be an open procedure or a closed procedure wherein the direct visualization may occur via a scope and/or other non- visual means of imaging (e.g., ultrasound, magnetic resonance imaging etc). If the temperature of the lens at the proximal end of the endoscope (if used) drops precipitously at the start of the liquefied gas spray, the moist air of the biological environment or of the air of the catheter which has been blown out ahead of the liquefied gas flow can condense on the lens, thereby obscuring the physician's view of the operative site. This can be substantially avoided by means of the suction pump which will immediately suck out the moist air which is present prior to the arrival of the liquid spray or cold gas. However, fogging should normally clear on its own when cryotherapy is performed, thereby eliminating the need for suction in many circumstances. Because of this pumping out of the moist air as the spray commences and the replacement with extremely dry gas, substantial amounts of moisture will not form on the lens 14 (Figs. IB, 2A, 2B and 2C) during the procedure, allowing an excellent view of the operative site by the physician during the procedure.

[0072] This condensation effect is augmented by the fact that the catheter itself may not be wrapped in additional insulation. This causes the temperature of the liquefied gas exiting the catheter at the distal end to be relatively high at the beginning of the spraying operation and gradually cooling as the catheter cools. Indeed, in the tests conducted in pigs 10-20 seconds may be necessary before significant freezing is seen through the endoscope. If the catheter is substantially insulated, the interior of the catheter will cool much more quickly as it will not be picking up heat from the outside. With this insulated catheter, it is to be expected that the liquefied gas would be sprayed onto the target tissue almost immediately, causing much faster freezing and, thus, allowing less control on the part of the physician.

[0073] Another reason that the lens does not fog or frost in the present invention is that the reproductive tissues can be flushed out with the liquefied gas, which is extremely dry. The liquefied gas is moisture free because it is condensed out of atmospheric gases at a temperature -197°C (when nitrogen is used), colder than the temperature at which moisture is condensed out.

[0074] The combination of relatively warm, and completely dry nitrogen gas, with or without suction, flushes moist air from the reproductive tract. As the temperature of the liquefied gas entering the reproductive tissues falls, so does the surface temperature of the camera lens 14. Ordinarily at that time the lens 14 would be cold enough to condense moisture and fog, however, since the reproductive tract is dried out (in contrast to its usual highly moist state) there is little or no moisture to condense. Thus, the lens 14 stays un-fogged and un-frosted and continues to provide a clear view of the operation. On the other hand, if the reproductive tissues are not vented with suction and/or not preliminarily flushed with dry gas (perhaps because the catheter is insulated, lowering its heat capacity, and/or the liquefied gas delivery pressure is too high), then the lens may fog or frost and the physician cannot operate effectively for a limited time.

[0075] In order to deal with the moist air problem a suction tube 41 (FIGS. 3 and 4) can be supplied. During the cryosurgical procedure the suction tube can be inserted prior to inserting the endoscope 10 and catheter 20. The suction tube 41, when connected to a pump 45, can serve to evacuate moist air from the reproductive tract prior to cryosurgery. With moist air removed, the television camera lens 14 is not obscured by fog and the physician can perform cryosurgery with an unobstructed view. Alternatively, if fogging occurs during cryosurgery, the suction tube and pump can be used to evacuate the reproductive tissues.

[0076] The composition of the catheter or the degree of insulating capacity thereof can be selected so as to allow the freezing of the targeted tissue to be slow enough to allow the physician to observe the degree of freezing and to stop the spray as soon as the surface achieves the desired whiteness of color (cryofrost). The clear observation results from the removal of the moist air and sprayed liquefied gas by the vacuum pump; in combination with the period of flushing with relatively warm liquefied gas prior to application of the spray of the liquefied gas which is caused by the relative lack of insulation of the catheter. The catheter can have a degree of insulation which permits at least five seconds to pass from the time cryogen begins to flow from the cryogen source to the time that liquefied gas is sprayed onto the targeted tissue.

[0077] The components or paraphernalia required to practice the method of the present invention may be packaged and sold or otherwise provided to health-care providers in the form of a kit. The kit is can be sealed in a sterile manner for opening at the site of the procedure. The kit can include the catheter, having the spray orifice at one end, as well as a connecter for connecting the catheter to the source of liquefied gas. This connecter may be a simple luer connection on the opposite end of the catheter from the spray orifice. One skilled in the art will appreciate that any other connecter that allows the catheter to be connected to the gas source may be used. [0078] Certain of the components of the cryosurgical system can be conventional medical appliances. For example, the endoscope or hysteroscope can be a conventional medical appliance and would not necessarily have to be supplied as part of a kit. One of the components to be supplied in a kit or sterilized package can be a catheter.

[0079] The unit can be attached to the gas supply tube through a luer lock connection and can be supplied to the user in a sterile package or kit. The endoscope may either be part of the kit or an available conventional endoscope may be used in conjunction with the remaining components of the kit. The kit may also optionally contain a suction tube that can be connected to a source of suction (e.g., a vacuum pump) or any other device or apparatus which will accomplish the function of withdrawing gas from the tube. The vacuum pump is optionally omitted from the kit as a source of vacuum is often found in hospital rooms or practitioner offices in which such a procedure is to take place.

[0080] The term "container" or "package" when used with respect to the kit is intended to include a container in which the components of the kit are intended to be transported together in commerce. It is not intended to comprehend an entire procedure room in which the individual components may happen to be present, an entire vehicle, a laboratory cabinet, etc.

[0081] When used in connection with a spray pattern, the term "substantially perpendicular" is not intended to limit direction of the spray to a plane at an angle of 90 degrees to the axis of the catheter, but includes any type of spray which will allow the targeted tissue that is coaxial to the catheter to be sprayed, near the locus of the tip of the catheter and to exclude a spray which is only substantially axial.

[0082] In some embodiments, the gas is not suctioned off or the gas is trapped, to aid in the increase of pressure as considered necessary by the physician. This may be useful, for example, for distension of the uterus.

[0083] In one embodiment of the present invention, it is contemplated that withdrawing gas will be necessary. If a hysteroscope is used for cryospray treatment of the uterus, it is contemplated that the cervix will close on the hysteroscope and will not allow adequate venting of gas. In such situations it is contemplated that the fallopian tubes will be blocked in order to prevent cryogenic gas from escaping into the abdomen. In one embodiment, the gas can be withdrawn via a tube, which may be inserted before or after inserting the endoscope 10 and catheter 20. The tube may or may not be connected to a suction pump, depending on the volume of gas that needs to be evacuated. Said tube may be separate from the endoscope, may be inserted through a channel in the endoscope 22, or may be inserted in a lumen which runs alongside the endoscope, such as that described in U.S. Patent Application No. 11/956,890, filed December 14, 2007, which is incorporated by reference herein in its entirety.

[0084] Each of the steps set forth in the method claims herein are likewise intended to comprehend not only the specific acts described in the specification, but any other acts which will accomplish the function set forth in the method step. Thus, for example, the step of adjusting the catheter may be accomplished by hand or by any other technique up to and including use of a complicated remote controlled robotic adjusting apparatus. The same is true for all of the other method steps for performing specified functions.

[0085] The preliminary test results indicate that a 5 second "cryofrost" time over varying cycles was adequate to ensure the appropriate tissue destruction, and thus appropriate cellular healing of damaged tissue for many applications. "Cryofrost" is a term defined by the instance that the normally "pinkish" targeted tissue turns white (much like freezer burn). A range for the "cryofrost" time could be about 5-10 seconds to about 2 minutes or more depending on the substrate to be treated.

[0086] Due to the nature of the system, "cryofrost" may not immediately occur, but may require that the fitting and catheter system become cool so that cryogen being sprayed from the distal end of the catheter is adequately cold to effect the cryofrost. This can require approximately 20-30 seconds from the time that the cryogen begins to flow. Of course, this time may be longer or shorter depending on the temperature of the cryogen, the length of the flow path, the materials from which the system is constructed and environmental conditions.

[0087] During animal testing the approximate temperature that cryofrost was first observed was at approximately -10⁰C. The temperature range for cryofrost would be approximately - 10 to -90⁰C.

[0088] The methods of the present invention can be performed using the CryoSpray

Ablation™ System (Model CC2-NAM, CSA Medical, Inc), which is a cryosurgical device intended to be used as a cryosurgical tool for the destruction of unwanted tissue. Medical Grade liquid nitrogen can be applied to unwanted tissue via the CSA™ Catheter, which is introduced through the working channel of a therapeutic endoscope or hysteroscope. The system enables the physician to control the start and stop of cryogen flow and thus the duration of the cryogen spray to the selected site. Freezing techniques can be monitored by direct visualization with an endoscope or hysteroscope and/or with non-optical visualization methods (e.g., ultrasound, magnetic resonance imaging etc).

[0089] The CryoSpray Ablation™ System is an FDA cleared, Class II device "intended to be used as a cryosurgical tool for the destruction of unwanted tissue in the field of general surgery, specifically for endoscopic applications" (K072651). As defined by the FDA, the CSA System is a cryosurgical unit with a liquid nitrogen cooled cryocatheter and accessories used to destroy tissue during surgical procedures by applying extreme cold. This delivery of liquid nitrogen results in tissue ablation and allows for the regrowth of normal, healthy tissue.

[0090] An apparatus for use in at least one method of the invention is shown in FIGs. IA and IB. In one embodiment, the method can include performing cryospray ablation utilizing a suitable therapeutic endoscopic device having a catheter inserted therethrough, where the endoscope and catheter can be inserted into a patient's vagina and/or cervix in order to visualize the uterus or other reproductive tissues. The catheter can be positioned to allow a cryogen fluid spray to be disposed adjacent a tissue to be treated (the "target tissue" or "target area"). The target reproductive tissue of the patient can then be sprayed with a cryogen fluid spray.

[0091] A catheter 20 can be disposed through lumen 18 of an endoscope. The size of the catheter should be selected to fit within the narrow diameter of the working channel of a therapeutic endoscope. However, larger or smaller catheters can be used. For example, the methods of the invention may include the use of hysteroscopes such as Hysteroscopes from Stryker®, Semi Flexible Mini Hysteroscopes, Hysteroscopes with Titanium Direct Coupler, Operating Laproscopes from Medifix Inc., or Hysteroscopes or Hysteroresectoscopes from Olympus. Alternatively, a endoscope with a larger working channel can be a conventional TEFLON catheter size 7 French of about 2-3 mm outside diameter.

[0092] The catheter 20 protrudes from the distal end 12 of the endoscope 10 and extends through the scope to the proximal end 30 where a physician's hand Hl can guide the catheter 20. As used herein, the terms "proximal" and "distal" respectively refer to locations closer to and farther away from the cryogen source along the length of the fluid connections and catheter extending therefrom. By way of example, the proximal end of a catheter or endoscope will generally remain outside of a patient during use, while the distal end of said catheter or endoscope will be inserted into the patient. As seen in the monitor image 28 of FIG. 4, the distal end 12 of the catheter 20 may be bent at an angle. [0093] The catheter 20 can be coupled to a cryogen source, such as a container 72 filled with liquid nitrogen or other liquified gas LG. As used in the present specification, "gas" in the phrase "liquified gas" means any fluid which is physiologically acceptable and which has a sufficiently low boiling point to allow the cryotherapy of the present invention. For example, such boiling point is preferably below about -150⁰C. Examples of such gases include nitrogen, as it is readily available, and argon. Such gases may also be referred to as a "cryogen." However, the term "cryogen" also refers to any fluid whether in liquid or gas form that is or was sufficiently cold to allow the cryotherapy.

[0094] Fig. 3 shows schematically the catheter 20 connected to a source of liquid nitrogen and inserted into the working channel of endoscope 10. The pressure within the container can be controlled by the physician or other provider to permit adequate spray from the distal end of the catheter. Any suitable device may be used, for example, a pressure-building loop as described in US Pat. No. 7,025,762. Additional embodiments and further details regarding the apparatus are also described in U.S. Pat. No. 7,025,762, which is hereby incorporated by reference in its entirety.

[0095] The flow of liquified gas from the cryogen source may be controlled using any structure known in the art, for example, a simple thumb-valve, a mechanical valve or an electromechanical valve. The valve may be controlled by a trigger mechanism, or the like, as could be readily envisioned and constructed by those of ordinary skill in the art. In an embodiment, an electrically operated solenoid valve may be employed to deliver the liquified gas to the catheter. The solenoid can be specifically adapted to function properly at low temperatures.

[0096] As the liquid gas moves through the catheter 20, it starts to boil and cool gas rushes ahead to emerge from the distal end or catheter tip. The boiling point of nitrogen is about - 196⁰C. Thus, when nitrogen is used as the cryogen, low pressure liquid moving through the catheter will be less than -15O⁰C. The amount of boiling in the catheter 20 depends on the mass and thermal capacity of the catheter. Since the catheter is of small diameter and mass, the amount of boiling can be small. After the catheter is cooled to a low temperature, and becomes filled with liquefied gas, the liquefied gas reaches the distal end of the catheter 20 near the distal end of endoscope 12 and begins to spray out of the catheter onto the appropriate target tissue. It is to be noted that the apparatus may be able to freeze the tissue sufficiently without actual liquefied gas being sprayed from the catheter, and that a spray of liquid may not be needed if the very cold gas (for example, nitrogen gas at less than O⁰C) can accomplish the task of freezing the targeted tissue.

[0097] Freezing is apparent to the physician by the frozen tissue acquiring a white color (cryofrost), due to surface frost (visible on the monitor 28 in FIG. 3); the white color indicates tissue freezing sufficiently to destroy the diseased tissue. The physician manipulates the endoscope 10, vent 42, and/or catheter 20 to freeze all of the targeted tissue. Once the operation is complete, the endoscope 10 with catheter is withdrawn.

[0098] The apparatus similar to that shown in Figure 3 can also be used with the methods of the present invention. Various component of Figure 3 are more fully described in U.S. Pat. No. 7,025,762 to Johnston et al. , which is incorporated by reference. Other apparatuses capable of delivering liquid cryogen to a catheter, particularly low temperature, low pressure cryogen, may also be employed.

[0099] Effective cryotherapy can be achieved without gross damage to the tissue (for example, there is no laceration). Thus, there can be no need to treat the frozen area. The cells of the endothelium soon die, and the lining is sloughed off to be replaced by healthy tissue.

[00100] Because the invention uses liquid spray via a catheter 20 rather than contact with a cold solid probe, there is little risk of a cold apparatus sticking to and tearing the tissue. Even if contact is made between the catheter and the tissue, the plastic material of the catheter, such as TEFLON, is in little danger of sticking to the tissue because of its low thermal conductivity and specific heat. Furthermore, the catheter need not touch the tissue according to many embodiments.

[00101] In embodiments that involve spraying liquid cryogen directly onto tissue, the cooling rate (rate of heat removal) is much higher than with a solid, contact probe because the sprayed liquefied gas can evaporate directly on the target tissue, which absorbs much of the heat of vaporization. The rate of rewarming is also high, since the applied liquid boils away almost instantly. No cold liquid or solid ultimately remains in contact with the tissue, and the depth of freezing can be minimal if desired.

[00102] Since freezing is accomplished by boiling liquefied gas (e.g., nitrogen), large volumes of this gas can be generated. This gas can be provided with a mechanism to escape in order to minimize the chance of pressure-related injury. The local pressure can be higher than atmospheric because the gas can encounter resistance flowing out of the reproductive tract, provided the fallopian tubes are blocked, as discussed above. There can be provided several alternative methods for facilitating the evacuation of gas from the reproductive tract.

[00103] The reproductive tract may be suctioned with a separate tube 41. A suction tube 41 as seen in FIG. 3, which can run outside of and adjacent to the endoscope 10. Suction may be provided by a suction pump 45 or other conventional suction device. Alternatively, an escape path may be provided by an additional lumen in the endoscope. Additional lumens, such as lumen 22, are provided on so-called "therapeutic" endoscopes. "Diagnostic" endoscopes typically have only one lumen, which would be occupied by the liquified gas-delivery catheter 10 when such a endoscope is used. The use of a multi-lumen "therapeutic" endoscope can provide an extra lumen for use as an escape path for gas venting. The application of suction to such a vent lumen can also be provided.

[00104] FIG. 2B shows a catheter tip on the end of the catheter 20 and adapted to spray liquefied gas through one or more openings 49 on catheter 20. When a lateral hole is provided in the wall of the catheter, the distal end of the catheter can be closed so that cryogen is directed laterally. The length of the catheter tip and size and shape of the spray holes can be chosen so that the entire area of the targeted tissue is frozen at once without the need for manipulating the endoscope or catheter to freeze the targeted area in sequential increments. The catheter tip may be of rigid material such as metal or stiff plastic, preferably the latter. Alternatively, the entire endoscope and/or catheter may be moved up or down the treated tissue to ensure that the entire targeted area is sprayed.

[00105] FIGs. 2A, 2B, and 2C also show the distal end 12 of the endoscope 10 including a camera lens 14, illuminating light 16, biopsy channel or lumen 18 with the catheter 20 therein, and an additional lumen 22. The endoscope shown in FIG. 2 is a conventional therapeutic endoscope. A diagnostic endoscope or ENT scope would lack extra lumen 22.

[00106] The catheter will have one or more openings 49, whereby cryogen spray exits the catheter and contacts the tissue. The openings may be configured in such as way as to allow the cryogen to spray in a substantially perpendicular direction. When used in connection with a spray pattern, the term "substantially perpendicular" is not intended to limit direction of the spray to a plane at an angle of 90 degrees to the axis of the catheter, but includes any type of spray which will allow the targeted tissue of the lumen that is coaxial to the catheter to be sprayed, near the locus of the tip of the catheter and to exclude a spray which is only substantially axial. [00107] The end of the catheter 20 may also be cut at an angle to deflect the spray to one side as shown in FIG. 2 A. Alternatively, FIG. 2C shows an optional cone-shaped structure 110 disposed around the opening in the catheter to direct the spray to the target tissue.

[00108] The present invention has been illustrated and described in detail above. The embodiments described herein should be considered illustrative and not limiting of the scope of the invention. Those of skill in the art will appreciate that various changes and modifications can be made to the embodiments described above and those variations and modification are intended to be within the scope of the invention as set out in the appended claims. All references, patents and other printed materials mentioned above are specifically incorporated herein by reference in their entirety.

Claims

What is claimed is:

1. A method of ablating reproductive tissue, comprising applying cryogen to the reproductive tissue in need of ablation, or using cryogen to create an isotherm in proximity to said reproductive tissue in need of ablation.

2. The method of claim 1, wherein said cryogen is selected from the group consisting of oxygen, nitrogen dioxide, carbon dioxide, nitrogen, argon or room air.

3. The method of claim 1, wherein said cryogen is a liquid cryogen.

4. The method of claim 2, wherein said liquid cryogen is nitrogen.

5. The method of claim 1, wherein said cryogen is sprayed directly on said reproductive tissue.

6. The method of claim 3, wherein said liquid cryogen is sprayed directly on said reproductive tissue.

7. The method of claim 6, wherein said reproductive tissue is contacted with cryogen or is in proximity to the isotherm for a period of time sufficient to ablate said reproductive tissue.

8. The method of claim 1, wherein said method is performed during a surgical procedure.

9. The method of claim 1, wherein said cryogen is applied using a device comprising an endoscope.

10. The method of claim 8, wherein said endoscope is a hysteroscope.

11. The method of claim 3, wherein said cryogen is applied at low pressure.

12. The method of claim 3, wherein said cryogen is applied using a device comprising a catheter.

13. The method of claim 12, wherein said catheter is made of a low pressure material.

14. The method of claim 13, wherein said low pressure material is selected from the group consisting of polytetrafluoroethylene, Pebax, nylon or polyimide.

15. The method of claim 1 , further comprising introduction of a barrier capable of preventing gas from entering the fallopian tubes.

16. The method of claim 15, wherein said barrier is selected from the group consisting of a balloon, plug, dam, or sheet.

17. The method of claim 1, wherein said reproductive tissue is labial tissue, vaginal tissue, cervical tissue, uterine tissue, fallopian tube tissue, or ovarian tissue.

18. The method of claim 17, wherein said uterine tissue is endometrial tissue.

19. The method of claim 18, wherein said endometrial tissue is found outside the uterus.

20. The method of claim 19, wherein said method is a method of treating a patient with endometriosis.

21. The method of claim 1 , wherein said treatment is for removal of damaged, diseased or unwanted tissue.

22. The method of claim 21, wherein said tissue is cancerous or pre-cancerous.

23. The method of claim 22, wherein said tissue benign.

24. The method of claim 21, wherein said tissue is of trophoblastic origin.

25. The method of claim 24, wherein said tissue is a hydatidiform mole.

26. The method of claim 1, wherein said treatment is for dilation and curettage.

27. The method of claim 3, wherein said treatment is for dilation and curettage.

28. The method of claim 1 , further comprising administration of additional therapeutic compounds.

29. The method of claim 28, wherein said additional therapeutic compounds are administered prior to cryospray treatment.

30. The method of claim 28, wherein said additional therapeutic compounds are administered during cryospray treatment.

31. The method of claim 28, wherein said additional therapeutic compounds are administered after cryospray treatment.

32. A method of treating reproductive tissue, comprising applying cryogen to the reproductive tissue in need of treatment, or using a cryogen to create an isotherm in proximity to said reproductive tissue in need of treatment.

33. The method of claim 32, wherein said cryogen is selected from the group consisting of oxygen, nitrogen dioxide, carbon dioxide, nitrogen, argon or room air.

34. The method of claim 33, wherein said cryogen is a liquid cryogen.

35. The method of claim 35, wherein said liquid cryogen is nitrogen.

36. The method of claim 32, wherein said cryogen is sprayed directly on said reproductive tissue.

37. The method of claim 34, wherein said liquid cryogen is sprayed directly on said reproductive tissue.

38. The method of claim 34, wherein said reproductive tissue is contacted with cryogen or is in proximity to the isotherm for a period of time sufficient to provide a therapeutic effect to said reproductive tissue.

39. The method of claim 32, wherein said method is performed during a surgical procedure.

40. The method of claim 32, wherein said cryogen is applied using a device comprising an endoscope.

41. The method of claim 40, wherein said endoscope is a hysteroscope.

42. The method of claim 34, wherein said cryogen is applied at low pressure.

43. The method of claim 34, wherein said cryogen is applied using a device comprising a catheter.

44. The method of claim 43, wherein said catheter is made of a low pressure material.

45. The method of claim 43, wherein said low pressure material is selected from the group consisting of polytetrafluoroethylene, Pebax, nylon or polyimide.

46. The method of claim 32, further comprising introduction of a barrier capable of preventing gas from entering the fallopian tubes.

47. The method of claim 46, wherein said barrier is selected from the group consisting of a balloon, plug, dam, or sheet.

48. The method of claim 32, wherein said reproductive tissue is labial tissue, vaginal tissue, cervical tissue, uterine tissue, endometrial tissue, fallopian tube tissue, or ovarian tissue.

49. The method of claim 32, wherein said treatment is for abnormal bleeding.

50. The method of claim 49, wherein said abnormal bleeding is abnormal menstrual bleeding.

51. The method of claim 49, wherein said abnormal bleeding is a result of trauma.

52. The method of claim 49, wherein said abnormal bleeding is postpartum bleeding.

53. The method of claim 32, wherein said cryogen is applied to the reproductive tissue for a sufficient amount of time to initiate hemostasis, or cryogen is used to create an isotherm in proximity to said reproductive tissue for a sufficient amount of time to initiate hemostasis.

54. The method of claim 32, wherein said treatment is for infection.

55. The method of claim 54, wherein said infection is selected from a group consisting of bacterial, viral or fungal infections.

56. The method of claim 32, wherein said treatment is for modulating an immune response.

57. The method of claim 32, further comprising administration of additional therapeutic compounds.

58. The method of claim 57, wherein said additional therapeutic compounds are administered prior to cryospray treatment.

59. The method of claim 57, wherein said additional therapeutic compounds are administered during cryospray treatment.

60. The method of claim 57, wherein said additional therapeutic compounds are administered after cryospray treatment.