Abstract: Apparatus and methods for cooling selected regions within a body are described herein. An implantable cooling system is used to cool regions of the brain, spinal cord, fibrous nerve bodies, e.g., vagus nerve, etc. down to about 30° C. to diminish nerve impulses which control seizures or chronic pain. The system includes an implantable unit containing a pumping mechanism and/or various control electronics. It also has a heat exchanger attachable to a tubular body organ, such as the superior vena cava or the inferior vena cava, through which the heat is effectively dissipated. Also included is a heat pump such as a Peltier junction configured to be placed into contact with the region of tissue to be cooled. The heated portion of the Peltier junction is cooled by a liquid heat transfer medium which absorbs the heat from the junction and dissipates it into the tubular body organ.

Abstract: An electrosurgical probe (10) comprises a shaft (13) having an electrode array (58) at its distal end and a connector (19) at its proximal end for coupling the electrode array to a high frequency power supply (28). The shaft includes a return electrode (56) recessed from its distal end and enclosed within an insulating jacket (18). The return electrode defines an inner passage (83) electrically connected to both the return electrode and the electrode array for passage of an electrically conducting liquid (50). By applying high frequency voltage to the electrode array and the return electrode, the electrically conducting liquid generates a current flow path between the return electrode and the electrode array so that target tissue may be cut or ablated. The probe is particularly useful in dry environments, such as the mouth or abdominal cavity, because the electrically conducting liquid provides the necessary return current path between the active and return electrodes.

Abstract: A method and apparatus is provided for determining an effective thermal mass of a patient. The effective thermal mass is employed to determine a gain factor used in a feedback control system controlling patient temperature. The method begins by inducing hypothermia or hyperthermia in at least a selected portion of the patient with a device having a heat transfer surface. Next, power is transferred between the device and the patient. A change in temperature over time, which arises in the selected portion of the patient, is measured while performing the step of inducing hypothermia or hyperthermia. Finally, an effective thermal mass is calculated based on the measured power and the measured temperature change over time.

Abstract: An endovascular heat transfer device which can have a smooth exterior surface, or a surface with ridges and grooves. The device can have a plurality of elongated, articulated segments, with each having such a surface. A flexible joint connects adjacent elongated, articulated segments. The flexible joints can be bellows or flexible tubes. An inner lumen is disposed within the heat transfer segments. The inner lumen is capable of transporting a pressurized working fluid to a distal end of the heat transfer element.

Abstract: A multi-purpose device mechanism for sensing and control of changes in brain state includes a shaft portion and extendible elements structured for insertion into target tissue of the brain of a subject patient, cooling means configured to operatively apply cooling therapy to the target tissue, stimulation means having at least one electrical contact structured to operatively apply electrical stimulation therapy to the target tissue, sensing means including at least one sensor monitoring a biological signal of the subject patient, control means responsive to the sensing means wherein the control means is structured to, in response to signals from the sensing means that indicate the presence of a pre-determined physiological condition or occurrence of an undesirable state change, automatically cause the cooling means and/or the stimulation means to initiate or terminate the cooling therapy and/or the electrical stimulation therapy respectively and an energy source for powering the various components of the mult

Abstract: An electrosurgical probe (10) comprises a shaft (13) having an electrode array (58) at its distal end and a connector (19) at its proximal end for coupling the electrode array to a high frequency power supply (28). The shaft includes a return electrode (56) recessed from its distal end and enclosed within an insulating jacket (18). The return electrode defines an inner passage (83) electrically connected to both the return electrode and the electrode array for passage of an electrically conducting liquid (50). By applying high frequency voltage to the electrode array and the return electrode, the electrically conducting liquid generates a current flow path between the return electrode and the electrode array so that target tissue may be cut or ablated. The probe is particularly useful in dry environments, such as the mouth or abdominal cavity, because the electrically conducting liquid provides the necessary return current path between the active and return electrodes.

Abstract: A system (10) for cerebral temperature control of a living being, comprising a double lumen catheter means (30) configured to be introduced through a nostril of a living being and to be placed with its tip at the level of the back of the tongue. The double lumen catheter means (30) comprises a first lumen (32) and a second lumen (38), said first and second lumens are in fluid communication by means of a set of end openings (34), said second lumen being configured as an expandable balloon. Further comprising a temperature regulator (24) connected to a reservoir (20) comprising a fluid (22), said temperature regulator being configured to regulate the temperature of said fluid, and means (12, 14, 16) for circulating said temperature regulated fluid from said reservoir into said first lumen, from said first lumen into said second lumen, and from said second lumen back to said reservoir.

Abstract: Embodiments of the invention provide a system for temperature control of the human body. The system includes an indwelling catheter with a tip-mounted heat transfer element. The catheter is fluidically coupled to a console that provides a heated or cooled heat transfer working fluid to exchange heat with the heat transfer element, thereby heating or cooling blood. The heated or cooled blood then heats or cools the patient's body or a selected portion thereof. In particular, strategies for optimizing the rewarming of patients for various medical procedures are provided, including stroke, neurosurgery, and myocardial infarction.

Abstract: A probe that may be used to create circumferential lesions in body tissue and, in some implementations, may also be used to perform mapping functions. The probe includes a collapsible/expandable structure that supports electrodes or other operative elements against the body tissue.

Abstract: Improved devices, systems and methods for treating a tissue region provide straightforward, yet reliable ways for installing diverse functional components within the confined space of a catheter-based instrument.

Abstract: Methods and apparatuses for temperature modification of a patient, or selected regions thereof, including an induced state of hypothermia. The temperature modification is accomplished using an in-dwelling heat exchange catheter within which a fluid heat exchange medium circulates. A heat exchange cassette of any one of several disclosed variations is attached to the circulatory flow lines of the catheter, the heat exchange cassette being sized to engage a cavity within one of various described re-usable control units. The control units include a heater/cooler device, a user input device, and a processor connected to receive input from various sensors around the body and the system. The heater/cooler device may be thermoelectric to enable both heating and cooling based on polarity. A temperature control scheme for ramping the body temperature up or down without overshoot is provided.

Abstract: This surgical device uses a laser beam to coagulate tissue. The elongate device carries the beam through an optical fiber that has a chamfered end for deflecting the beam out of a distal end of the device at an angle. Tissue coagulation is monitored using a magnetic resonance imaging system that provides periodic tissue temperature data. A small fluid supply duct provides cooling fluid that expands to a gas near the distal end of the device, thereby cooling the tip.

Abstract: A high efficiency electrosurgical ablator which is subjected to a combined oscillatory and mechanical debridement motion during resection of tissue is disclosed. The electrosurgical ablator is positioned in the proximity of the tissue to be treated in the presence of an electrically conductive fluid. A high frequency voltage is applied to the electrode of the ablator, and the electrode is subjected to an oscillatory or other repetitive motion created by an element located within the ablator assembly. The ablator electrode is further connected to a suction assembly that supplies suction from an external source.

Abstract: A method and apparatus for creating a virtual electrode to ablate bodily tissue. The apparatus includes an outer tube, a first electrode, an inner tube and a second electrode. The outer tube is fluidly connected to a source of conductive fluid and defines a proximal end and a distal end. The distal end includes an opening for delivering conductive fluid from the outer tube. The first electrode is disposed at the distal end of the outer tube for applying a current to conductive fluid delivered from the outer tube. The inner tube is coaxially received within the outer tube and is connected to a source of conductive fluid. The inner tube defines a proximal end and a distal end, with the distal end forming an opening for delivering conductive fluid from the inner tube. Finally, the second electrode is disposed at the distal end of the inner tube for applying a current to conductive fluid delivered from the inner tube.

Abstract: Disclosed is an apparatus and method for uniform selective cerebral hypothermia. The apparatus includes a brain-cooling probe, a head-cooling cap, a body-heating device and a control console. The brain-cooling probe cools the cerebrospinal fluid within one or more brain ventricles. The brain-cooling probe withdraws a small amount of cerebrospinal fluid from a ventricle into a cooling chamber located ex-vivo in close proximity to the head. After the cerebrospinal fluid is cooled it is then reintroduced back into the ventricle. This process is repeated in a cyclical or continuous manner. The head-cooling cap cools the cranium and therefore cools surface of the brain. The combination of ventricle cooling and cranium cooling provides for whole brain cooling while minimizing temperature gradients within the brain.

Abstract: A helical ablation electrode extends from a distal end of the shaft and includes a first portion extending from a first end winding about a first diameter, a second portion extending from the first portion and winding about a second diameter smaller than the first diameter, and a second end terminating the second portion. The electrode further includes a fluid lumen extending from a location in proximity to the first end of the electrode to a location in proximity to the second end of the electrode and in fluid communication with a fluid delivery lumen of the catheter shaft. An irrigation fluid delivered through the fluid delivery lumen of the catheter shaft, from a fluid port, passes through the fluid lumen of the ablation electrode to cool the electrode.

Abstract: Disclosed is a method and system for inducing selective cerebral hypothermia. The system includes a brain cooling device, a body warming device, and a control console. Brain cooling is accomplished with a ventricle catheter where cold fluid is circulated within one or both lateral ventricles. Body heating is accomplished with a central venous catheter. By combining effective brain cooling with controlled body warming, hypothermia therapy can be applied selectively to the brain thereby avoiding the serious complications associated with whole body hypothermia therapy.

Abstract: Radiation applicators comprise an elongate device having an antenna (240, 340) at their tip for coupling radiation into biological tissue and a dielectric body (250, 350) surrounding the antenna so as to encompass substantially the whole of the near-field region of the antenna and/or to enhance transmission of radiation in the forward direction. The body (250, 350) may be cylindrical with the antenna (240, 340) along its axis. The antenna may be ?/2 in length and ?/2 in radius. The tip (270) of the antenna (240) may be rounded hemispherical with radius ?/2 to enhance forward transmission of radiation. The dielectric constant (?) of the body (250, 350) is as high as possible to reduce its diameter at a desired operating frequency but may be matched to the surrounding tissue by another layer of dielectric material (380) with a value (?) intermediate that of the core (360) of the body (350) and the tissue.

Abstract: Apparatuses, systems, methods, and computer code for, among other things, monitoring the health of samples such as the brain while providing local cooling or heating. A representative device is a heat transfer probe, which includes an inner channel, a tip, a concentric outer channel, a first temperature sensor, and a second temperature sensor. The inner channel is configured to transport working fluid from an inner inlet to an inner outlet. The tip is configured to receive at least a portion of the working fluid from the inner outlet. The concentric outer channel is configured to transport the working fluid from the inner outlet to an outer outlet. The first temperature sensor is coupled to the tip, and the second temperature sensor spaced apart from the first temperature sensor.

Abstract: The present invention provides systems and methods for selectively applying electrical energy to a target location within a patient's body, particularly including tissue in the spine. The present invention applies high frequency (RF) electrical energy to one or more electrode terminals in the presence of electrically conductive fluid to contract collagen fibers within the tissue structures. In one aspect of the invention, a system and method is provided for removing a vertebral disc in preparation for implanting a prosthetic disc or removing a portion of the vertebral disc such as the nucleus pulposus in preparation for placing a prosthetic nucleus within the annulus of the disc. The present invention also teaches shrinking residual tissue in preparation for placing the implants.

Abstract: A method of achieving tissue changes in bone or bone-derived organic tissue, in which method bone or bone-derived organic tissue is provided, an interfacing agent is applied to the bone or bone-derived organic tissue, and electromagnetic energy is applied to the interfacing agent. The interfacing agent can include collagen, preferably bone-derived collagen, and a therapeutic agent. In a related embodiment, a method of treating bone tissue is provided wherein a bioactive interfacing agent is placed between the bone segments of the bone tissue to be treated.

Abstract: A virtual ablation electrode assembly includes a non-conductive outer cap fitted over an inner electrode to form a fluid chamber between a cap inner surface and an exterior surface of the electrode. The inner electrode includes an interior fluid trunk and one or more fluid distribution branches extending from the fluid trunk to the exterior surface. A plurality of pores extends between the cap inner surface and a cap outer surface. When the electrode is energized and when fluid is delivered through the one or more fluid distribution branches from the trunk, the conductive fluid fills the fluid chamber and flows out from the chamber through the plurality of pores of the cap establishing ionic transport of ablation energy from the inner electrode to a target site in close proximity to the cap.

Abstract: A system for exchanging heat with the body of a patient for cooling or warming the patient provides for automatic temperature control in accordance with the monitored temperature of the patient. The system comprises a temperature control module and temperature probes for making body core temperature measurements. The body core temperature measurements are used to control the temperature of fluid circulating within the fluid circuit.

Abstract: A medical assembly and method are provided to effectively treat abnormal tissue, such as, a tumor. The target tissue is thermally ablated using a suitable source, such as RF or laser energy. A cooling shield is placed in contact with non-target tissue adjacent the target tissue, and actively cooled to conduct thermal energy away from the non-target tissue. In one method, the cooling shield can be placed between two organs, in which case, one of the two organs can comprise the target tissue, and the other of the two organs can comprise the non-target tissue. In this case, the cooling shield may comprise an actively cooled inflatable balloon, which can be disposed between the two organs when deflated, and then inflated. The inflatable balloon can be actively cooled by pumping a cooling medium through it. In another method, the cooling shield can be embedded within the non-target tissue. In this case, the cooling shield can comprise one or more needles.

Abstract: A device and method for providing body cooling. The cooling device applies cooling to blood flowing in a vena cavae that is then distributed throughout the body. The cooling can be assisted by use of thermoregulatory drugs or warming devices to prevent shivering and vasoconstriction.

Abstract: A fluid circuit for circulating coolant in a closed loop between an intravascular catheter and a heat exchange system includes a buffer IV bag in fluid flow series with the catheter between the catheter and a pump that pumps the coolant to the heat exchange system. A conventional IV bag is connected by means of a spike and tube to the buffer bag.

Abstract: A device and method for providing body cooling for treating fever. The cooling device applies cooling to blood flowing in a vein or artery, e.g., the vena cavae, that is then distributed throughout the body.

Abstract: A group of multiple hollow fibers may be shaped to introduce angular divergence among the fibers, or to introduce a selected longitudinal oscillation into the fibers. In one shaping technique, the fibers are held in parallel while upper and lower crimping assemblies of parallel crimping bars are drawn together on opposite sides of the parallel fibers. When bars of the opposing assemblies draw sufficiently close, they sandwich the fibers in between them, causing each fiber to assume a shape that oscillates as the fiber repeatedly goes over and then under successive bars. Since the crimping bars are aligned at oblique angles to the fibers, the peaks and troughs of successive fibers are offset. While in this position, the fibers are heated and then cooled to permanently retain their shapes. A different shaping technique utilizes a lattice of criss-crossing tines defining multiple apertures. In this technique, the lattice and fibers are positioned so that each fiber passes through one of the apertures.

Abstract: A cryotherapy system is provided with multiple cryoprobes, each of which has a shaft with a closed distal end adapted for insertion into a body and conduits for flowing a cryogenic fluid through the shaft to reduce a temperature of the distal end. A source is provided for the cryogenic fluid, and flow-control metering valves are provided in fluid communication with the conduits and source of the cryogenic fluid. A compressor is provided in fluid communication with the conduits of the cryoprobes to define a self-contained fluid system. The flow-control metering valves and the compressor are controlled by a computer processor to provide the desired flows of the cryogenic fluid through the conduits of the self-contained fluid system.

Abstract: A balloon catheter is used in a closed-loop heat exchange system for manipulating the temperature of a patient. The balloon catheter is positioned in the stomach of the patient, and then expanded with a heat exchange fluid delivered through a lumen formed in the shaft of the catheter. The balloon catheter comes into contact with the wall of the stomach, and the stomach substantially conforms around the expanded balloon catheter. The heat exchange fluid is allowed to flow continuously into and out of the balloon catheter. Heat is exchanged between the balloon catheter and the stomach so as to controllably alter the temperature of at least a portion of the patient. Anti-shivering mechanisms and automatic control based on temperature feedback from the patient may be used in connection with the heat exchange system.

Abstract: Apparatus and methods for advancing and retracting a medical instrument within an introducer device, wherein the instrument includes a distal tip, a distal linear portion, a first distal curve, a substantially linear inter-curve portion, and a second proximal curve. The length of the distal linear portion and the angle of the first curve determine the position of the distal tip within a lumen of the introducer device, such that the distal tip occupies a substantially central transverse location within the lumen and the distal tip avoids contact with the introducer device. The length of the inter-curve portion and the angle of the second curve determine deflection of the distal tip from a longitudinal axis of the shaft when the second curve is extended distally beyond a distal end of the introducer device. Also, methods and apparatus for treating an intervertebral disc by ablation of disc tissue.

Abstract: An intravenous heat exchange catheter and/or an external cooling pad/bladder can be used to maintain hypothermia in, e.g., a cardiac arrest patient, but to accelerate the cooling process the patient first can be infused with cold saline before the opportunity arises to connect the catheter or pad to the patient.

Abstract: An endovascular heat transfer device which can have a smooth exterior surface, or a surface with ridges and grooves. The device can have a plurality of elongated, articulated segments, with each having such a surface. A flexible joint connects adjacent elongated, articulated segments. The flexible joints can be bellows or flexible tubes. An inner lumen is disposed within the heat transfer segments. The inner lumen is capable of transporting a pressurized working fluid to a distal end of the heat transfer element.

Abstract: An intravascular heat transfer device is provided with a mixing-inducing surface formed by an easily manufacturable process. The device can have a plurality of elongated, articulated segments, each having a mixing-inducing exterior surface. A flexible joint connects adjacent elongated, articulated segments. The device may be conveniently formed, e.g., by vapor deposition or molding, and further lacks undercuts so that the same may be conveniently removed from, e.g., a two-part mold.

Abstract: A method and apparatus for performing hypothermia of a selected organ without significant effect on surrounding organs or other tissues. A flexible catheter is inserted through the vascular system of a patient to place the distal tip of the catheter in an artery feeding the selected organ. A compressed refrigerant is pumped through the catheter to an expansion element near the distal tip of the catheter, where the refrigerant vaporizes and expands to cool a flexible heat transfer element in the distal tip of the catheter. The heat transfer element cools the blood flowing through the artery, to cool the selected organ, distal to the tip of the catheter.

Abstract: An apparatus having an inflatable balloon near a distal end of a multi-lumen catheter, with a plurality of blood flow passageways formed through the interior of the balloon from a proximal face of the inflated balloon to a distal face of the inflated balloon. A heat transfer solution is introduced through a supply lumen of the catheter to inflate the balloon in a selected blood vessel; this allows blood to flow through the blood flow passageways of the balloon, from one exterior face of the balloon to another exterior face. The heat transfer solution continues to circulate around the blood flow passageways inside the balloon, to change the blood temperature, eventually exiting the balloon through a return lumen of the catheter.

Abstract: A medical device is provided having a means for actuating a pair of opposing jaw members. The jaw members are movable relative to one another from a first position, wherein the jaw members are disposed in a spaced apart relation relative to one another, to a second position, wherein the jaw members cooperate to grasp tissue therebetween. An ablation tool is connected to at least one of the jaws members, such that the jaw members are capable of conducting ablation energy through the tissue grasped therebetween.

Abstract: An elongate, malleable ablation probe including an elongate malleable body (38) and a plurality of longitudinally spaced apart electrodes (40) disposed at a distal end thereof. The electrodes (40) are separated one from another by insulative material. In one embodiment, a malleable insert is provided for insertion into a flexible longitudinal sleeve, the flexible longitudinal sleeve conforming to the shape of the malleable insert upon such insertion. In other embodiments, a malleable core is surrounded by a flexible body, the electrodes (40) being mounted to the body.

Abstract: A catheter includes a plurality of primary leads to deliver energy for ligating a hollow anatomical structure. Each of the primary leads includes an electrode located at the working end of the catheter. Separation is maintained between the primary leads such that each primary lead can individually receive power of selected polarity. The primary leads are constructed to expand outwardly to place the electrodes into apposition with a hollow anatomical structure. High frequency energy can be applied from the leads to create a heating effect in the surrounding tissue of the anatomical structure. The diameter of the hollow anatomical structure is reduced by the heating effect, and the electrodes of the primary leads are moved closer to one another. Where the hollow anatomical structure is a vein, energy is applied until the diameter of the vein is reduced to the point where the vein is occluded. In one embodiment, a balloon is inflated to occlude the structure before the application of energy.

Abstract: A handpiece has a handpiece assembly and includes a handpiece housing. An insert is detachably coupled to the handpiece housing. The insert includes an RF electrode with a conductive portion and a dielectric.

Abstract: A method, device, and system for treatment of urinary tract disorders is provided. The device includes a catheter having multiple lumens for insertion into a urinary bladder and for providing fluid flow within the bladder and within the fluid reservoir within the urethra. The device further includes an anchor to be placed within the bladder. A port hub having multiple ports is connected at a proximal end of the catheter. A method of treatment includes providing heated fluid to a urinary bladder and to a fluid reservoir for insertion into an adjacent organ such as the urethra. Simultaneous treatment or separate treatment may be done. Optionally, a medicated solution may be added to the heated fluid. Additionally, pressure may be adjusted so as to optimize the therapeutic effect.

Abstract: Whole body cooling of a patient is obtained by providing a catheter with a conductive heat transfer element at a distal end thereof, inserting the catheter and heat transfer element into the vascular system of the patient and utilizing the heat transfer element to modify the temperature of blood which flows in heat exchange proximity to the heat transfer element, such that the modification of the blood will accomplish whole body cooling of the patient. The conductive metallic heat transfer element includes a plurality of heat transfer segments, and at least one helical ridge and at least one helical groove formed on each or the plurality of heat transfer segments.

Abstract: A method for treating cardiac arrest includes defibrillating the patient and/or ventilating the patient and/or administering a cardiac arrest drug such as epinephrine to resuscitate the patient, and then cooling the patient using one or more cooling catheter positioned in the central venous system of the patient.

Abstract: Methods, systems, and computer program products for providing thermal therapies or internal thermal massage therapy for treating prostatitis by expanding and contracting a treatment balloon with inflation media and currently applying heat to a portion of the prostatic urethra.

Abstract: A method and apparatus for lowering the body temperature of a patient while reducing shivering by using a heat exchange device in combination with an ?2-adrenoreceptor agonist, a non-opiod analgesic monoamine uptake inhibitor or neuropeptide that temporarily reduces shivering. The devices disclosed include a catheter having a heat exchange balloon thereon with heat exchange fluid circulating through the interior of the balloon. The heat exchange balloon is placed in the vasculature of a patient, and heat exchange fluid at a temperature other than the temperature of the blood in the vasculature is circulated through the interior of the balloon to add or remove heat from the blood of the patient. Various ?2-adrenoreceptor agonist?2-adrenoreceptor agonists, non-opiod analgesic monoamine uptake inhibitors and neuropeptides are disclosed including dexmedetomidine, nefopam, neurotensin and anticonvulsant medications and pharmaceutically acceptable salts thereof.

Abstract: The invention provides a medical device having a thermister for temperature measurement, irrigation/aspiration ports for fluid exchange and application of therapeutic modalities, a pressure manometer for pressure measurement, and an external system for control of temperature, pressure, and flow rate. When applied to the central nervous system (CNS), this device can be used in hypothermia or hyperthermia applications, the exchange of cerebral spinal fluid (CSF), the application of treatment modalities, and the insertion of a ventriculostomy or ventriculostomy-like unit. When applied to spinal cord applications, this device can provide temperature control and a method for application of treatment modalities by using a venting device placed in the space surrounding the spinal cord, a device with similar instrumentation to measure temperature and pressure. A device for ultrasound localization of the CNS device is described. A device for a fiber optic endoscope for visualization and localization is also described.

Abstract: The invention provides a single-use, disposable circulation set for a heat transfer catheter.

Abstract: Various types of insulated coolant lines that extend between a heat exchanger and an intravascular heat exchange catheter are disclosed.

Abstract: A method and apparatus for transmural ablation using an instrument containing two electrodes or cryogenic probes. A clamping force is exerted on the two electrodes or probes such that the tissue of the hollow organ is clamped therebetween. Bipolar RF energy is then applied between the two electrodes, or the probes are cryogenically cooled, thus ablating the tissue therebetween. A monitoring device measures a suitable parameter, such as impedance or temperature, and indicates when the tissue between the electrodes has been fully ablated.

Abstract: A catheter is described. In one embodiment, the catheter includes: a shaft segment including a shaft segment uptake lumen and a shaft segment return lumen; and a distal end segment coupled to the shaft segment, the distal end segment including a distal end segment uptake lumen and a distal end segment return lumen, where the distal end segment central axis forms a non-zero angle with the shaft segment central axis when the catheter is in its unstressed configuration. In a second embodiment, the catheter includes: a shaft segment; and a distal end segment coupled to the shaft segment; where the uptake lumen distal end is terminated by a closed surface, further where the uptake lumen distal segment includes only one side hole. In a third embodiment, the catheter includes: an uptake lumen; and a return lumen; where at least a portion of the return lumen distal segment is helically coiled around the uptake lumen distal end.