Abstract: A living body heating instrument is pushed or inserted into an affected part to continuously perform cauterization and vaccinotherapy. A living body heating instrument that is pushed or inserted into an affected part of a living body to heat the affected part includes: an inner needle; and an outer needle having a hollow portion into which the inner needle is inserted through an opening at the needle base side toward the needle tip side. The inner needle has biocompatibility and thermal conductivity, and contains a heater. The affected part is cauterized by the heater with the inner needle inserted in the outer needle. Next, the inner needle is withdrawn, and a drug is injected through the outer needle, which remains inserted, to perform immunotherapy. A temperature detecting element may be provided in an inner part of the inner needle or on an outer surface of the outer needle.

Abstract: Systems, instruments, and methods are described in which an apparatus comprises a housing including a scalpet device. The scalpet device includes a scalpet array that includes scalpets arranged in a pattern. The scalpets are deployable from the housing to generate incised skin pixels at a target site. The housing is positioned and the scalpet array is deployed into tissue at the target site. Incised skin pixels are generated when the target site is a donor site, and skin defects are generated when the target site is a recipient site. The incised skin pixels are harvested.

Abstract: Electrosurgical system with selective control of active and return electrodes. At least some of the illustrative embodiments are systems comprising an electrosurgical wand and an electrosurgical controller. The wand comprises a non-conductive outer surface, at least three electrodes disposed on a distal end of the wand, and at least three electrical leads extending from a proximal end of the wand (one electrical lead electrically coupled to each electrode). The controller comprises a voltage generator and a control circuit coupled between the voltage generator and the electrodes of the wand. The control circuit is configured to: selectively electrically couple the active terminal singly and in combination to the electrodes of the wand; and selectively electrically couple the return terminal singly and in combination to electrodes of the wand.

Abstract: Various embodiments are directed to systems and methods for providing segmented power curves to tissue. A surgical generator may receive an indication of a first impedance of tissue to be treated by a surgical end effector. The generator may determine that the first impedance is within an impedance range corresponding to a first power curve segment of the segmented power curve and provide a drive signal to the end effector according to a first power curve. The generator may further receive an indication of a second impedance of the tissue to be treated by the end effector, determine that the second impedance is within an impedance range corresponding to a second power curve segment of the segmented power curve, and provide the drive signal to the end effector according to a second power curve.

Abstract: A needle electrode deployment shaft includes a central member and a plurality of needle electrodes. The central member has a plurality of needle advancement channels formed therein. The needle electrodes are disposed within the advancement channels and each advancement channel terminates in a ramp portion which deflects the needles radially outwardly as they are axially advanced. The ramps may be spirally or acutely configured in order to increase the distance through which the needles may be bent as they are axially advanced. Additionally, the central member may have a radially reduced distal tip in order to decrease tissue insertion forces.

Abstract: A device for treating tissue includes a catheter including an elongated body extending from a proximal end to a distal end and including a lumen extending therethrough, a distal tip connected to the distal end of the elongated body and including a first electrode and a second electrode extending thereabout, the first electrode extending to a distal opening of the lumen and a first needle extending longitudinally from a proximal end to a distal end, the first needle slidably received within the lumen of the catheter to be moved between a retracted bipolar configuration, in which the distal end of the needle is proximal the distal opening of the catheter, and an extended monopolar configuration, in which the distal end of the first needle extends distally past the distal opening of the catheter so that the first needle contacts the first electrode and is configured to cut tissue.

Abstract: A method and apparatus are disclosed for a system that maps the proximal and distal ablation subzones and their respective margins using the tools that are used to access the ablation target wherein the tools have markings to indicate which probe and balloon kyphoplasty (BKP) system or vertebroplasty (VP) system to use. Examples of access tools comprise introducers, stylets, and bone drills. In some embodiments of the system, the probe has a marking indicating which BKP or VP system to use.

Abstract: A tissue interface module has an applicator chamber on a proximal side of the tissue interface module and a tissue acquisition chamber on a distal side of the tissue interface module. The applicator chamber may include: an opening adapted to receive the applicator; an attachment mechanism positioned in the applicator chamber and adapted to attach the tissue interface module to the applicator; a sealing member positioned at a proximal side of the applicator chamber; and a vacuum interface positioned at a proximal side of the applicator chamber and adapted to receive a vacuum inlet positioned on a distal end of the applicator. The invention also includes corresponding methods.

Abstract: Electrosurgical forceps in which one or more pairs of non-resonant unbalanced lossy transmission line structures are arranged on the inner surfaces of the jaws of the forceps provide both (i) active and return electrodes for a radiofrequency (RF) signal, and (ii) lossy structures for delivering a microwave signal into biological tissue in conjunction with a mechanical gripping arrangement for applying pressure to material held within the jaws. The location of the pairs of transmission lines on the jaws of the forceps and the selection of the material of the jaws is arranged to ensure that any biological tissue gripped by the jaws become the propagation medium for the RF signal and the medium into which the microwave signal is lost.

Abstract: A microwave delivery device, including a coaxial feedline having an inner conductor, an inner dielectric insulator coaxially disposed about the inner conductor, and an outer conductor coaxially disposed about the inner dielectric, and a radiating portion operably coupled to a distal end.

Abstract: Provided is a surgical handpiece for providing an electromagnetic cutting blade. The handpiece, comprises a body portion having an input end and an output end, a plurality of optical fibers for receiving laser energy having a wavelength within a predetermined wavelength range, wherein the optical fibers are received in the body portion at the input end and extend to the output end, and an optical fiber transition region within the body portion for arranging the plurality of optical fibers into a predetermine cutting shape at the output end, wherein laser energy transmitted from the arranged optical fibers at the output end interact with water molecules near the surgical target to generate micro-explosions that result in a cutting effect.

Abstract: Embodiments include a system for determining cardiovascular information for a patient. The system may include at least one computer system configured to receive patient-specific data regarding a geometry of the patient's heart, and create a three-dimensional model representing at least a portion of the patient's heart based on the patient-specific data. The at least one computer system may be further configured to create a physics-based model relating to a blood flow characteristic of the patient's heart and determine a fractional flow reserve within the patient's heart based on the three-dimensional model and the physics-based model.

Abstract: A method of pre-operatively forming a surgical splint configured to receive a patient's dentition can include combining a 3-D facial computer model and a 3-D dental computer model. The method includes the step of obtaining a 3-D facial computer model of at least the patient's maxilla, mandible, and dentition from a CT scanner and the step of obtaining a 3-D dental computer model of the patient's dentition with an optical scanner. The 3-D dental computer model is then combined with the 3-D facial computer model to form a composite virtual model. The composite virtual model can be manipulated into a planned post-operative shape, and a surgical splint can be custom constructed to match the planned post-operative shape. The surgical splint can be configured to receive the patient's dentition.

Abstract: A method for avoiding impingement between an implanted prosthetic hip stem and acetabular cup uses at least one digital x-ray of a standing patient preferably including a lateral x-ray to determine a pelvic tilt angle of the patient. A hip stem is virtually implanted at an initial stem version angle into a virtual femur constructed from the digital x-ray. Data of at least one hip joint motion is obtained from at least one individual. A range of inclination and anteversion angles is calculated for a virtually implanted acetabular cup that avoids impingement with the virtually implanted hip stem. The calculated range of inclination or anteversion angles is based at least in part on the pelvic tilt angle of the patient, the initial hip stem version angle and the obtained joint motion data.

Abstract: A method for determining a volume of ablated tissue includes the steps of supplying energy to tissue, indicating an axis within the tissue, and simulating slicing of the tissue substantially perpendicular to the axis to obtain a plurality of simulated slices. Each of the plurality of simulated slices has a thickness, a cross-sectional perimeter, and a trajectory point defined by the axis within the tissue. The method further includes the steps of determining a volume of each of the plurality of simulated slices based on the trajectory point, the cross-sectional perimeter, and the thickness of each simulated slice, and summing the volumes from each of the plurality of simulated slices to obtain the volume of the ablated tissue.

Abstract: An apparatus for moving an elongate rod longitudinally and rotationally, and a method of moving the elongate rod longitudinally and rotationally, are provided. A translation member has a first translation member end held relatively stationary and a longitudinally spaced second translation member end which is selectively movable longitudinally with respect to the first translation member end via actuation of the translation member. The second translation member end is operatively connected to selectively impart longitudinal motion to the elongate rod. A rotation member has a first rotation member end held relatively stationary and a longitudinally spaced second rotation member end which is selectively rotatable with respect to the first rotation member end via actuation of the rotation member. The second rotation member end is operatively connected to selectively impart rotational motion to the elongate rod.

Abstract: A surgical system for selective connection to a robotic arm includes an instrument drive unit, an instrument support platform coupled to the instrument drive unit, an instrument carriage coupled to the instrument support platform, and a surgical instrument releasably coupled to the instrument carriage. The surgical instrument includes an end effector controllable to perform surgery in response to telemanipulation of actuators in the instrument drive unit.

Abstract: A medical manipulator system including: a medical manipulator having a joint; an operating section having an operating system; and a control unit controlling the medical manipulator according to an operation applied to the operating section. The operating section includes a switch enters or releases a command. The control unit determines whether a deviation between the joint and the operating system exceeds a threshold while the command is entered, carries out a first motion for moving the joint by a displacement corresponding to the displacement of the operating system if the deviation is equal to or smaller than the threshold, carries out a second motion for approaching the joint to the operating system angle if the deviation exceeds the threshold, and stops the motion for approaching the joint to the operating system angle when the command is released when the deviation exceeds the threshold.

Abstract: This sensor storage container comprises a bottomed cylindrical container body (1) having an opening in its top face, an opening/closing lid (2) provided to the opening of the container body (1) in an openable/closable manner, and an inner case (7) that is open at its top face and provided within the container body (1). The opening/closing lid (2) is linked to the container body (1) via a hinge portion (3), at the peripheral edge of the opening of the container body (1). The inner case (7) is linked on the hinge portion (3) side to the opening/closing lid (2).

Abstract: A flexible, sterilizable pouch includes a first wall coupled to a second wall and a cavity defined between the first wall and the second wall. The cavity is configured to receive a medical device, and the pouch is configured to seal the medical device within the cavity. At least one of the first wall and the second wall of the pouch includes two layers. Each layer is coupled to the adjacent layer such that a breach in any one layer of the multi-layered wall will not breach the seal of the pouch. A pocket may be formed between the layers of the multi-layered wall and may include a gas under pressure to inflate the corresponding wall to an inflated state.

Abstract: A container for disposal of medical waste is provided that comprises a receptacle with an open top. A lid is attached to the receptacle to cover the open top of the receptacle. The lid has an elongated opening sized to permit the introduction of medical waste into the receptacle. A closure flap is connected to the lid to selectively close the lid opening. The closure flap is movable between an open position, a closed position and a locked position. The closure flap is attached to the lid by axial hubs that extend from each side of the closure flap through openings in the side walls of the lid. Covers attached to the outside of the side wall of the lid and engaged with the closure flap axial hub. The container may also include a locking external cabinet that encloses the receptacle and can be mounted to a wall.

Abstract: A surgical illumination apparatus comprises a fiber optic input, and illuminated surgical instrument, and an optical coupling bracket for coupling the fiber optic input to the illuminated surgical instrument. The coupling bracket comprises an elongate frame having a proximal end, a distal end, and a central channel extending therebetween, wherein the central channel is sized to receive and support optical fibers of the fiber optic input. The proximal end of the bracket is coupled to the fiber optic input, and the distal end of the bracket is coupled to an illumination element of the illuminated surgical instrument. The apparatus may further comprise a shroud disposed around the illumination element that is coupled to the bracket.

Abstract: A handle assembly comprised of a base and a detachable handle that mounts to the base. The base includes integrated electronics, such as switches. The detachable handle includes buttons for activating the switches.

Abstract: A collector used to collect bone includes: a container body defining an interior containment space for receiving and retaining collected bone, and having at least one open end for access and removal of collected bone from the interior containment space; and a cap in covering relation to the open end of the container body such that access to the interior containment space for removal of collected bone is inhibited. The collector includes an intake port defining an opening for receiving therein a distal end of a kerrison rongeur for collecting cut bone from a cutting area thereof, and the cap includes at least one scraper for engaging and dislodging cut bone from the cutting area of a distal end of a kerrison rongeur when received within the intake port. The collector preferably is used with a kerrison rongeur for collecting cut bone therefrom.

Abstract: A device for simultaneously identifying a plurality of surgical instruments or instrument groups includes a first detecting device having a first detection technology for detecting instruments and, if applicable, related instrument-specific information. The device also includes a second detecting device having a second different detection technology for detecting instruments and instrument information. Moreover, the device includes a comparing device for comparing the detection results of the two detecting devices. The comparing device outputs a positive evaluation regarding the correctness of the detected instruments if the two detection results are matching.

Abstract: A dental instrument with an elongated tip housing a ball within a socket. The exposed surface of the ball may be pressed against a restorative material on a tooth surface in order to evenly distribute the restorative material without incorporating air bubbles. A dental instrument may have a second elongated tip housing a ball on an opposing end. The elongated tip housing the ball may be removably attached or may be rotatable.

Abstract: An endodontic file includes a handle and a bore formed entirely through the handle, and a fluted shank extending from the handle along an axis. A notch is formed in communication with the bore, and the notch is configured to open only in a direction along the axis to define an entrance to the bore only in a direction transverse to the axis.

Abstract: A method for continuously evaluating the effectiveness of debridement of a root canal of a tooth, the tooth having an open access cavity and an apex end, includes delivering a fluid to the open access cavity of the tooth, evacuating the fluid near the apex end of the tooth such that the fluid flushes most of the root canal before being evacuated, and continuously evaluating the evacuated fluid for at least one of a presence of debris, a concentration level of the debris, or a type of the debris. An apparatus for use in debriding a root canal of a tooth includes a microcannula or a macrocannula configured to evacuate a fluid in the root canal, and a sensing mechanism fluidically coupled to the microcannula or the macrocannula, the sensing mechanism configured to continuously sense debris in the evacuated fluid in real time.

Abstract: A lightweight, small footprint, composite extraction pen, for the delivery of dental filling composite from commercially available composite filled carpules. An electric linear actuator is housed in a slender, pen-like housing configured to accept, constrain and allow the rotational positioning of commercially available composite filled carpules. The carpules are contained within an adaptor that connects to the body of the pen. The linear actuator extends and retracts a piston through a bore in the carpule so as to exert pressure on the composite contained therein. The pen provides precise composite delivery while maintaining a highly visible dental environment.

Abstract: A dental device includes a rounded flexible device configured to attach onto a head of a dental drill. The rounded flexible device has a first pair of opposing horizontal protrusions positioned at a first end of the rounded flexible device; a second pair of opposing horizontal protrusions positioned at a mid-portion of the rounded flexible device, wherein the first pair of opposing horizontal protrusions extend horizontally beyond the second pair of opposing horizontal protrusions; and a central vertical protrusion positioned at a second end of the rounded flexible device. The first pair and the second pair of opposing horizontal protrusions are configured to partially encircle the head of the dental drill, and the central vertical protrusion is configured to extend a length of a rotating drill bit of the dental drill.

Abstract: An orthodontic bracket is provided. The orthodontic bracket includes a base part; a bracket body mounted on the base part and having a retaining projection provided on an upper face thereof; a clip having a U-shaped cross-section, the clip being mounted on the bracket body and including an upper part along the upper face of the bracket body, a lower part along a lower face of the bracket body, a curved part therebetween, and an engaging hole provided in the upper part of the clip in a position that corresponds to a position of the retaining projection of the bracket body such that the retaining projection projects through the engaging hole when the clip is in an open position thereon; and an archwire slot in the upper face of the bracket body that extends perpendicular to a moving direction of the clip.

Abstract: A dental implant system for bone regeneration of a bone defect site of a jawbone includes an implant which is to be anchored in the jawbone, a film for covering the bone defect site and the implant, a spacer element which, in a fitted position of the dental implant system, is to be arranged between the implant and the film, and an abutment. In the fitted position of the dental implant system, the film is clamped between the spacer element and the abutment, and the spacer element and the abutment are connected by a form-locked connection.

Abstract: Lithium silicate glass ceramics and glasses comprising specific oxides of trivalent elements are described which crystallize at low temperatures and are suitable in particular as dental materials.

Abstract: An animal positioner includes two forelimb positioning members cylindrically attached to forelimbs of an animal, respectively, so as to wrap the forelimbs; two hindlimb positioning members cylindrically attached to hindlimbs of the animal, respectively, so as to wrap the hindlimbs, the two hindlimb positioning members being longer than the forelimb positioning members; a trunk positioning member which is longer than the hindlimb positioning members, the trunk positioning member being cylindrically attached to a trunk of the animal so as to wrap the trunk between the forelimb positioning members which are attached to the forelimbs of the animal, respectively, and the hindlimb positioning members which are attached to the hindlimbs thereof, respectively; and a head positioning member attached to a head of the animal so as to form a truncated cone circumferential surface and wrap the head above the forelimb positioning members.

Abstract: An applicator for use in the veterinary medical field for spraying vaccines and other medicaments, biologicals or other liquids and compositions intra-rectally. The applicator has an elongated, hollow tubular body with a connector at its proximal end for connection to a fluid supply and a curved distal end tip with a pair of apertures for dispersing fluid by spraying action.

Abstract: A valve insertable into a body lumen includes a body region extending in a distal direction away from a proximal rim. The proximal rim defines an outer perimeter of the valve at a proximal end of the valve. The body region forms a first leaflet and a second leaflet, with the first leaflet in contact with the second leaflet to provide the valve with a closed position. The first leaflet includes a first segment in contact with the proximal rim and a second segment in contact with the second leaflet. The first segment is curved to include a convex exterior surface and a concave interior surface of the valve. The second segment is curved to include a concave exterior surface and a convex interior surface of the valve.

Abstract: A cannula cut spiral flow inducing stent includes a plurality of spiral inducing flow diverters that each include a piece of sheet metal with a helically shaped flow surface. A proximal stent region, which includes a plurality of first struts, is joined to a proximal end of each of the spiral inducing flow diverters. A distal stent region, which includes a plurality of second struts, is joined to a distal end of each of the spiral inducing flow diverters. All of the first struts and all of the second struts share a cannula thickness, but the shaped pieces of sheet metal may have a lesser thickness.

Abstract: The invention relates to a vascular prosthesis system for inserting into and for supporting a blood vessel of a patient. The vascular prosthesis system comprises (i) a stent graft element comprising a prosthesis material, and (ii) a stent element free of prosthesis material. Furthermore, a strip-like prosthesis material segment is provided, by means of which the stent graft element and the stent element are connected to each other, in such a way that the strip-like prosthesis material segment forms a prosthesis material bridge.

Abstract: Described embodiments are directed toward prosthetic valves and systems and methods of making prosthetic valves. In accordance with an embodiment, a prosthetic valve comprises and leaflet frame, and outer frame and a film. The leaflet frame has a generally tubular shape defining a plurality of leaflet windows. The outer frame has a generally tubular shape. The leaflet frame is coaxially disposed at least partially within the outer frame. The leaflet frame and outer frame is coupled at least in part by a contiguous portion of the film. At least a portion of the contiguous portion of the film is contained between and coupling the leaflet frame and outer frame operable to prevent relative movement and contact therebetween. The film defines a leaflet extending from each of the leaflet windows.

Abstract: A paravalvular leak resistant prosthetic heart valve system including a stent frame, a valve structure and a sealing mechanism. The stent frame has a surface. The valve structure is associated with the stent frame. The sealing mechanism at least partially extends over the surface of the stent frame. The sealing mechanism includes at least one semi-permeable membrane and an osmotic gradient driving material.

Abstract: A mitral valve prosthesis is percutaneously and/or transapically deployed in at least two stages. In a first stage, a mitral annular ring platform adapted for percutaneous delivery is delivered to and anchored in the mitral valve annulus. In the second stage, a valved-stent mitral valve prosthetic device adapted for percutaneously delivery is delivered to the mitral valve annulus for mounting in the mitral annular ring platform. This approach provides a consistent platform for accepting valved-stent mitral valve prosthetic devices from different vendors to be used.

Abstract: The present disclosure relates to an arrangement, a loop-shaped support, a prosthetic heart valve and a method of repairing or replacing a native heart valve. With the method or the arrangement, leakage or regurgitation between a prosthetic heart valve and the surrounding valve tissue is prevented. In one embodiment, an arrangement for replacement or repair of a native heart valve is provided, which comprises a loop-shaped support 41 and a prosthetic heart valve 70 and wherein an outer segment 32 of the loop-shaped support 41 is positionable towards surrounding valve tissue of a native heart valve and wherein an outer surface 74 of the prosthetic heart valve 70 is positionable towards an inner segment 34 of the loop-shaped support 41 so as to prevent paravalvular leakage or regurgitation between the prosthetic heart valve 70 and the surrounding valve tissue of the native heart valve.

Abstract: A prosthetic heart valve includes a stent extending in a longitudinal direction and having a plurality of commissure features. A valve assembly is secured to the stent, the valve assembly including a cuff and a plurality of leaflets. Each of the leaflets has a pair of attachment regions and a free edge extending between the attachment regions. A deflection feature disposed in each attachment region is configured and arranged to prevent the free edges of the leaflets from contacting at least one of the stent or the cuff.

Abstract: A heart valve assembly (100) includes a heart valve (116), a self-expandable and collapsible stent (112), and a sealing member (114). The stent (112) includes an inflow end (120) and an outflow end (122), and surrounds and supports the heart valve (116). The sealing member (114) is connected to the inflow end (120) of the stent (112) and extends around a periphery of the stent (112). The sealing member (114) is connected to the inflow end (120) of the stent (112), overlaps a portion of the heart valve (116), and extends around an outer periphery of the stent (112).

Abstract: Prosthetic heart valve devices and associated methods for percutaneous or transcatheter heart valve replacement are disclosed herein. A heart valve prosthesis configured in accordance herewith includes a frame having a valve support and a plurality of support arms extending therefrom. The plurality of support arms may include a main support arm configured to extend from the valve support for capturing at least a portion of a valve leaflet of a native heart valve therebetween when the valve prosthesis is in an expanded configuration and deployed within the native heart valve. In addition, the plurality of support arms may include multiple supplemental support arms disposed about the circumference of the valve support that when deployed in the expanded configuration are configured to at least partially engage subannular tissue at the native heart valve.

Abstract: A prosthetic heart valve includes a collapsible and expandable stent including a plurality of struts forming cells, the stent having a proximal end, a distal end, an annulus section adjacent the proximal end, an aortic section adjacent the distal end, and a transition section disposed between the annulus section and the aortic section, the aortic section having a larger diameter than the annulus section. The heart valve further includes a valve assembly disposed entirely in the annulus section of the stent for controlling the flow of blood through the stent, the valve assembly including a plurality of leaflets, and a cuff, the cuff being disposed on a surface of the stent and extending fully over at least two rows of cells of the stent.

Abstract: A prosthetic heart valve for replacing a native valve includes a collapsible and expandable stent extending between a proximal end and a distal end, the stent including an annulus section adjacent the proximal end and an aortic section adjacent the distal end. The annulus section has cells arranged in at least one annulus row, each annulus row having a same first number of cells, the first number defining a first cell density. The aortic section has cells arranged in at least one aortic row, each aortic row having a same second number of cells, the second number defining a second cell density, the first cell density and the second cell density being different. A valve assembly is disposed within the stent.

Abstract: The invention relates to a transcatheter heart valve replacement (A61F2/2412), and in particular an orthogonally delivered transcatheter prosthetic valve having a tubular frame with a flow control component mounted within the tubular frame and configured to permit blood flow in a first direction through an inflow end of the valve and block blood flow in a second direction, opposite the first direction, through an outflow end of the valve, wherein the valve is compressible to a compressed configuration for introduction into the body using a delivery catheter for implanting at a desired location in the body, said compressed configuration having a long-axis oriented at an intersecting angle of between 45-135 degrees to the first direction, and expandable to an expanded configuration having a long-axis oriented at an intersecting angle of between 45-135 degrees to the first direction, wherein the long-axis of the compressed configuration of the valve is substantially parallel to a length-wise cylindrical axis of

Abstract: In a particular embodiment, the present disclosure provides a delivery apparatus for delivering a medical device. The delivery apparatus includes an elongated component with an engagement portion and a disengagement portion. Rotating the elongated component in a first rotational direction moves the travelling component along the engagement portion in a first axial direction. When the travelling component is located within the disengagement portion, continued rotation of the elongated component in the first rotational direction does not cause further movement of the travelling component in the first axial direction. A biasing member is located proximate the disengagement portion and urges the travelling component to reengage the engagement potion. The delivery apparatus can reduce or prevent damage to the delivery apparatus, or a patient with whom the delivery apparatus is used, by reducing or eliminating torque transfer from the travelling component to an end of the elongated component.

Abstract: A catheter that comprises a sheath that is connected at opposing ends to concentric tubes that move relative to each other in a manner that alternatively covers and exposes a medical device loaded onto the catheter. A portion of the sheath is arranged so as to invert upon itself so that axial movement of one tube relative to the other simultaneously moves the inversion point over or away from the device, alternatively covering or exposing the device.