Abstract: A cryosurgical instrument incorporates a heat transfer zone, which abuts against the portion of the cryosurgical instrument near the input refrigerant entrance, and which receives pure input refrigerant at the coldest temperature for quickly and effectively cooling this portion of the cryosurgical instrument. The cryosurgical instrument includes a shaft portion and a handle portion. The shaft portion includes an outer jacket tube having both an open and closed end. The closed end surrounds the freezing zone for freezing live tissue. A middle tube is disposed within the outer jacket tube. An inner tube is disposed within the middle tube. The inner tube is adapted for routing input cryogenic refrigerant therethrough to the freezing zone. The channel between the inner tube and middle tube forms a cryogenic refrigerant exhaust path for exhausting cryogenic refrigerant from the freezing zone.

Abstract: A new non-invasive, non-toxic, non-sedating method for treatment of vascular headaches (migraine and cluster), tension headache, atypical (chronic) facial pain, allergic rhinitis and cervical muscle spasm is presented. This method comprises the application of cold or frozen water or saline (0.degree.-4.degree. C.), cold metal, or ice to the area of tenderness associated with the plexus formed by the posterior and middle superior alveolar branches of the ipsilateral maxillary nerve, as well as to other branches of the trigeminal nerve. The cold or frozen water or saline can be applied indirectly when contained in small bags, tubes or packs made of plastic film, latex, silicone, or the like. Metal tubes can also be used which have been chilled by either running cold water or ice through their hollow interiors. Preferably plastic tubes encasing a column of ice, which ice can be extruded gradually by the patient or clinician by means of a plunger inserted into the tubes are used.

Abstract: An improved cryosurgical system includes means for cooling the cryoprobe instrument to temperatures below the normal boiling point of liquid nitrogen as well as means for recovering the sub-cooled liquid coolant. A unique cryoprobe instrument of simplified construction uses an active vacuum for thermal insulation. Means are provided for controllably adjusting the length of the freezing zone of the cryoprobe to allow the freezing zone to be adjusted for different sizes and shapes of tumors which may be "observed" before surgery by ultrasound imaging. Multiple, disposable cryoprobe instruments can be individually controlled for both operating temperature and freeze zone length. A preferred refrigeration system for sub-cooling liquid nitrogen refrigerant or other cryogenic liquid refrigerant is based on the principles of evaporative cooling.

Abstract: A surgical instrument comprising a probe for insertion into the body of a host and for manipulating the tissues of the host, the probe including an ultrasound transducer element for locating and positioning the probe within the body of the host; and a method for manipulating the tissues of a host using the surgical instrument.

Abstract: A process for removing obstructions to sinus drainage of patient. A cryoprobe cooled to about -100.degree. C. is inserted into one nostril of the patient and lodged inferiorly against the bone and lateral wall of the nose of the patient. The is maintained in this position for a period of about 90 seconds. Then the cryoprobe is moved within the first nostril to superior position and lodged against the sphenoid bone and cribriform plate of the ethmoid bone of the patient and maintained for about 90 seconds. The cryoprobe is then inserted into the other nostril and placed in the above two mentioned positions with the result that sinus drainage is markedly improved as is the sense of smell.

Abstract: A method of carrying out cryosurgical interventions includes cooling biological tissue at a rate of at least 180 K/min to a temperature of -190.degree. C. to -160.degree. C., subsequently rewarming the biological tissue at a rate of 100 to 240 K/min to a temperature of -70.degree. C. to -20.degree. C. with a subsequent rewarming at a rate of 10 to 25 K/min to a temperature of -5.degree. C. to +5.degree. C., and further rewarming the biological tissue up to body temperature. The total time of the controlled rewarming of the biological tissue is shorter than 5 minutes. An apparatus for carrying out the method of cryosurgical interventions includes a container of cooled medium an operating instrument, and a control unit for controlling the cooling and subsequent rewarming of biological tissue. The control unit includes a microprocessor coupled to electronic switches and a measuring unit.

Abstract: Cryosurgical probe tips (20,66) are in metallurgical contact with coils of insulated resistor wire (27, 27a) with one end connected through copper wire (75) to a pin (32) insertable into a switch (33, 34, 51-61) of a battery pack (35-50) which may be clipped (64) to cryosurgical apparatus (9-14), and the other end connected through cryogen liquid feed tube structure (19, 19a) and the cryosurgical apparatus to the other end of the battery pack.

Abstract: Cell and tissue destruction by cryoablation is enhanced by the perfusion of the cells with thermal hysteresis proteins prior to the cryogenic freezing. The effect of the proteins is to promote the growth of spicular ice crystals in the intracellular fluid which destroy the cell by piercing the cell membrane. This decreases the incidence of cell preservation by freezing, thereby permitting a more uniform and controllable destruction of undesirable tissue by the cryoablation technique.

Abstract: A determination is quantitatively made of the severity of pain exhibited at a specified area on an animal by determining the magnitude of cooling required at the area of pain in order for the pain to be masked or made to disappear. The amount of cooling required for pain disappearance is considered directly related to the severity of the pain. Hence, by measuring the temperature depression required to mask the pain in a patient, an examiner can determine just how serious is the pain, and additionally provide guidance in the selection of a specific medicine. There is always some finite temperature depression required for true pain to disappear. Should the patient alleges that no pain relief is encountered by the cooling of the painful area, the examiner considers that the patient is faking his pain.

Abstract: A method of thawing of cryosurgical apparatus, and in particular a cryosurgical probe, subsequent to a freezing process involves the interuption of the cryogen supply to the probe followed by the introduction of a warmed inert gas. The gas is circulated within the probe cryogen circulation system to affect thawing of the apparatus so that the probe may easily be withdrawn from the body. The gas, which may be nitrogen, is preferably passed through a heat exchange arrangement before being introduced into the probe.

Abstract: A closed end surgical cryoprobe instrument may have a probe shaft diameter of 3 millimeters or less and can achieve and maintain freezing zone temperatures close to that of the liquid cryogenic refrigerant. Using sub-cooled liquid nitrogen at approximately -208.degree. C. freezing zone temperatures as low as -206.degree. C. can be achieved in under 1 minute. The liquid nitrogen supply tube is provided with a plurality of small vent holes to vent gas formed or present in the refrigerant supply tube to the return refrigerant flow channel. The vent holes also allow small amount of liquid nitrogen to vent into the return flow channel to further reduce the temperature differential between the sub-cooled liquid nitrogen supply and the counter current flowing return refrigerant. Heat transfer is maintained through nucleate boiling. In place of vent holes, narrow slits may be provided in the supply tube. Alternatively, a sintered porous metal supply tube can be used as the vent means.

Abstract: An apparatus is provided for treating cutaneous vascular lesions in a target area of a patient. The apparatus has a lower housing having a bottom with an opening therethrough, and an upper housing adapted to be connected in liquid tight engagement to the lower housing. The upper housing has a top with an opening therethrough and substantially in alignment with the opening of the lower housing. A pair of glass windows are provided one positioned in the opening of the lower housing, and the other positioned in the opening of the upper housing. The apparatus further comprises at least one fenestrated wall adapted to be removably positioned in the lower housing to form a first and a second chamber when the upper and lower housings are connected together. The first chamber is adapted to receive a cooling medium, and the second chamber prevents the cooling medium from obstructing the passage of a laser beam between the pair of glass windows.

Abstract: Methods and apparatus for magnetic resonance imaging (MRI) assisted cryosurgery. Optimal probe placements and cooling parameters are calculated prior to cryosurgery using MRI data. A MRI compatible cryoprobe and a stereotactic probe positioning device are provided. The resolution of MR images is enhanced by mounting a radio frequency MR coil on the intracorporeal end of a cryoprobe. During cryosurgery the temperature distribution in the frozen region is solved by determining the boundary of the frozen region and solving the heat equation for the known boundary conditions. During cryosurgery the temperature distribution in the unfrozen region is determined by T1 measurements. The process of freezing is controled using information from the solution of the energy equation in the frozen region and temperature measurements in the unfrozen region. After cryosurgery the extent of the tissue damage may be ascertained using phosphorus-31 and/or sodium-23 spectroscopy with a special coil set on the cryosurgical probe.

Abstract: The invention provides a catheter for ice mapping and ablation and a method of ablation using the catheter. The catheter includes at least two conduits for circulating a refrigerating fluid adjacent an ablation device located at the end of a catheter. The refrigerated ablation device is used to chill a localized region of myocardial tissue, thereby permitting the resulting change in electrical activity to be determined. In response to the test results, the ablation device may be used to make a lesion in the myocardial tissue to correct a cardiac arrhythmia. In one embodiment, the ablation device is an electrode which uses radio frequency energy to ablate the myocardial tissue. Alternatively, the ablation device is an electrode adapted for direct current ablation. In another embodiment, the electrode is replaced with an optical fiber in communication with a laser which uses the laser's light energy to ablate tissue.

Abstract: A cryosurgical probe, insertable into a bodily cavity for performing cryosurgical ablation on the interior of the cavity, comprises a channel for introducing a heat-conducting liquid into the cavity, and a cooling element for cooling the heat-conducting liquid.

Abstract: A hose designed to facilitate supply and return of cryogenic fluid such as a liquefied gas includes supply and return conduits wrapped in multiple layers of reflective metallized material, which is surrounded by a layer of foam material which is, in turn, surrounded by a protective outer layer such as, for example, a woven cover. The conduits are made of a material such as polytetrafluoroethylene. The inventive hose is lightweight and maintains flexibility for extended periods of time with cryogenic fluid flowing through the conduits.

Abstract: An improved cryosurgical system includes means for cooling the cryoprobe instrument to temperatures below the normal boiling point of liquid nitrogen as well as means for recovering the sub-cooled liquid coolant. A unique cryoprobe instrument of simplified construction uses an active vacuum for thermal insulation. Means are provided for controllably adjusting the length of the freezing zone of the cryoprobe to allow the freezing zone to be adjusted for different sizes and shapes of tumors which may be "observed" before surgery by ultrasound imaging. Multiple, disposable cryoprobe instruments can be individually controlled for both operating temperature and freeze zone length. A preferred refrigeration system for sub-cooling liquid nitrogen refrigerant or other cryogenic liquid refrigerant is based on the principles of evaporative cooling.

Abstract: A cryogenic apparatus comprises a coolant system and a probe having a cryogenically-cooled cold-tip. The probe is formed of an elongated housing having a distal end closed by the cold-tip and a proximal end connected to the coolant system. The housing is adapted to receive cryogenic droplets entrained in a warm carrier gas stream supplied by the coolant system. The carrier gas stream passes through the housing such that the entrained cryogenic droplets are transported to the distal end of the probe for cooling the cold-tip.

Abstract: A pain alleviating tissue treatment assembly uses a combination of a cold electrode and an alterable current source to reduce the temperature of a selected tissue area, while at the same time applying various selected reversing and/or non-reversing currents to the selected tissue. A control console allows the operator to selectively operate the device in conjunction with biological feedback signals and further allows full recordation and/or control of the events as they occur through an attached computer system.

Abstract: The invention provides a catheter for ice mapping and ablation and a method of ablation using the catheter. The catheter includes at least two lumens for circulating a refrigerating fluid adjacent an ablation device located at the end of a catheter. The refrigerated ablation device is used to chill a localized region of myocardial tissue, thereby permitting the resulting change in electrical activity to be determined. In response to the test results, the ablation device may be used to make a lesion in the myocardial tissue to correct a cardiac arrhythmia. In one embodiment, the ablation device is an electrode which uses radio frequency energy to ablate the myocardial tissue. Alternatively, the ablation device is an electrode adapted for direct current ablation. In another embodiment, the electrode is replaced with an optical fiber in communication with a laser which uses the laser's light energy to ablate tissue.

Abstract: The invention provides a catheter for ice mapping and ablation and a method of ablation using the catheter. The catheter includes at least two lumens for circulating a refrigerating fluid adjacent an ablation device located at the end of a catheter. The refrigerated ablation device is used to chill a localized region of myocardial tissue, thereby permitting the resulting change in electrical activity to be determined. In response to the test results, the ablation device may be used to make a lesion in the myocardial tissue to correct a cardiac arrhythmia. In one embodiment, the ablation device is an electrode which uses radio frequency energy to ablate the myocardial tissue. Alternatively, the ablation device is an electrode adapted for direct current ablation. In another embodiment, the electrode is replaced with an optical fiber in communication with a laser which uses the laser's light energy to ablate tissue.

Abstract: A closed cycle cryosurgical instrument having a mixed gas assembly that is mounted in a housing and also having a cryosurgical probe unit. By using special (or certain) gas mixtures as opposed to pure gasses, pressure reductions to .perspectiveto. or 1/4 of that required by pure gasses can be obtained. The use of gas mixtures with their attendant lower pressures allows for a closed cycle system since expensive and complex multi-stage compressors are not required. With the gas mixtures it is possible to obtain temperatures in the range of liquid nitrogen using a Joule-Thomson based system.

Abstract: A cryosurgical probe for freezing human or animal tissue in a surgical procedure utilising the Joule Thomson effect. The probe is provided with a valve arrangement which enables selective purging and freezing cycles to be employed in rapid succession, and remote from the Joule-Thomson nozzle. In this way purging is limited to those parts of the probe which are affected by moisture contamination during the normal pre-sterilising process, and without interference with the Joule-Thomson nozzle.

Abstract: A thermoelectric cryoprobe for the topical treatment of neoplasms by freezing. The cryoprobe comprises a plurality of stacked thermoelectric modules coupled to a distal treatment tip through a heat pipe. Heat is dissipated by a heat exchanger system. An external control unit is provided which serves as a source of DC power for the hand-held cryoprobe and contains a control system for controlling the thermoelectric element based upon temperature feedback from treatment site. Temperature feedback from the sensors facilitates freeze-thaw cycling by the cryoprobe to more effectively destroy the tissue at the treatment site.

Abstract: The tube, known as a straw, according to the invention, is conventional in its form, and is constituted by a rectilinear length of transparent tubular envelope. In the vicinity of a first end, the straw contains a sliding stopper with a quantity of powder gellable by hydration between two porous pads. The tubular envelope is extruded from an ionomer resin marketed under the brand name of Surlyn 8921. Ionomer resins have, above and below a transition zone extending from 45.degree. C. to 60.degree. C. approximately, states that are respectively thermofusible and crosslinked. Thus, the straw can be closed by fusion of the ends clamped by heated jaws, while presenting suitable properties of rigidity at ambient temperature. Furthermore, the ionomer resin used does not have an embrittlement temperature, so that it can be manipulated at cryogenic temperatures (77 K) without the need for taking any particular precautions. The filling and sealing of the straws can be automated, to ensure the safety of the operators.

Abstract: A hand-held cryofixation apparatus in the form of a pistol handgrip into which is mounted a pneumatic cylinder and piston rod. A removable adapter and tissue mount is attached to the end of said piston rod. The handgrip is further fashioned with a slot or cutout into which is slidably disposed an L-shaped metal rod, the upturned leg of which supports a mirror finish metal block. Upon activation of the pneumatic cylinder the tissue mount is slammed against the mirror finish metal block which has been precooled by immersion into a cryogen such as liquid nitrogen or helium.

Abstract: An insulated, compact, mobile crysosurgical instrument is provided that has no moving parts in contact with a liquefied gas coolant retained in an insulated container. Upon interrupting normal venting from the container, the liquefied gas coolant will build up a pressure in the container which may be increased by a squeeze pressure device. That pressure will cause the liquefied gas coolant to spray from a nozzle until normal venting is restored.