Instruments and methods for deploying expandable implants

Abstract

A system for deploying an implant within a patient includes a deployment driver operable by moving a deployment control element. The deployment control element moves from a first position where the implant is not deployed to a second position where the implant is partially deployed, and then moves to a third position where the implant is completely deployed. The system also includes a positioning mechanism for preventing movement of the deployment control element from the second position to the third position. The positioning mechanism comprises a follower, and when the deployment control element moves from the first position to the second position, the follower can be driven to move to the deployment stop position, so that the deployment control element is prevented from further moving to the third position. The system includes a positioning release element that is movable to an unlocked position. The movement action of the positioning release element acts on the follower, so that the follower moves from the deployment stop position to the deployment release position; in the deployment release position, the deployment control element is freely movable from the second position to the third position.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a delivery instrument for an expandable implant and methods of use thereof. In particular, but not exclusively, the delivery instrument is suitable for deploying a self-expanding implant or dilator for dilating the prostatic urethra of a patient, thereby treating conditions such as benign prostatic hyperplasia. Accordingly, certain aspects and embodiments of the present invention relate to a delivery instrument for positioning an expandable implant (e.g. for treating benign prostatic hyperplasia by placement within the prostatic urethra) and a method of delivering or deploying such an implant.

[0002] Benign prostatic hyperplasia is a non-cancerous condition that causes the prostate to enlarge. The prostate surrounds a section of the urethra adjacent to the bladder, known as the prostatic urethra. As a result, as the prostate enlarges, it tends to press inwardly against the prostatic urethra and the bladder neck, causing the patient to experience difficulties in urinating.

[0003] In the United States alone, the cost of medication for treating benign prostatic hyperplasia exceeds $5 billion annually. A variety of surgical techniques are also currently available for treating benign prostatic hyperplasia. However, some surgical procedures are invasive and can cause significant discomfort to the patient. SUMMARY

[0004] Current medical practice is gradually moving towards the use of expandable implants or stents, which can be placed within the prostatic urethra to resist the inward pressure on the urethra and bladder neck caused by the enlarged prostate.

[0005] Expandable implants provide a minimally invasive and low-cost solution for the treatment of benign prostatic hyperplasia. However, placing the implant in the correct location within the urethra can be challenging for the clinician. If the implant is not deployed correctly, it can not only fail to adequately relieve symptoms, but can also fail due to migration or excessive scabbing, and can be difficult and invasive to remove from the urethra after implantation.

[0006] WO 2017 / 081326 discloses a variety of dilator embodiments for treating benign prostatic hyperplasia, the entire contents of which are incorporated herein by reference. The dilator of WO 2017 / 081326 can be positioned within the prostatic urethra (e.g. between the bladder neck and the external sphincter) and subsequently self-expand laterally. In one embodiment, the dilator relieves symptoms associated with benign prostatic hyperplasia by applying an outward radial force to the surrounding walls of the prostatic urethra.

[0007] In several embodiments, proper deployment of the dilator within the prostatic urethra requires ensuring its accurate positioning in both longitudinal and circumferential / angular directions. In particular, the dilator can be positioned longitudinally between the bladder neck and the external sphincter and brought into effective contact with the three lobes of the prostate through circumferential positioning. Accidental deployment, premature deployment, or failure of the clinician to clearly visualize the tissue structures surrounding the prostatic urethra prior to deployment can all result in misplacement of the implant.

[0008] If the dilator is deployed in the wrong location or orientation, it can result in adverse clinical outcomes and require removal or repositioning through a complex surgical procedure. Thus, there is a need for a minimally invasive delivery instrument that enables the clinician to accurately position and deploy the expandable implant within the prostatic urethra.

[0009] WO 2017 / 081326 describes embodiments of an instrument for delivering a dilator to a target site within a body lumen, such as the prostatic urethra. In several embodiments, the delivery instrument is equipped with an ejection element having a triangular cross-section that is structured to engage and support the dilator. The delivery catheter of the delivery instrument can be inserted transurethrally, and its distal end can be advanced along the urethra to the target site within the prostatic urethra. Once the clinician confirms that the dilator is in the desired position in both longitudinal positioning and relative angular orientation to the lobes of the prostate, the ejection element can be advanced forward to cause the dilator to exit the peripheral sheath of the delivery catheter.

[0010] Existing single-step delivery instruments can still be optimized for practical use. For example, certain single-step delivery instruments are prone to accidental or premature deployment. In addition, some single-step delivery instruments can fail to provide the clinician with an ideal visual confirmation mechanism prior to making a decision, and can not adequately verify the relative position of the dilator to the surrounding anatomical structures. Furthermore, unless the operator simultaneously performs the operations of withdrawing the proximal end of the delivery catheter and advancing the distal end of the ejection element, the dilator can be prone to forward movement or bouncing upon deployment. This shift due to the deployment action itself often results in the dilator’s position within the prostatic urethra, including both longitudinal and circumferential positioning. Given this, reliance on a self-positioning mechanism of the dilator relative to the anatomical structures can be unreliable and unpredictable.

[0011] WO 2021 / 099646, the entirety of which is hereby incorporated by reference, discloses various embodiments of improved delivery instruments for deploying dilators inside the prostatic urethra. In the improvements of WO 2021 / 099646, the following designs are included: preventing accidental deployment of the dilator; improving the visibility of the pre-deployment dilator relative to the surrounding anatomy; and being able to pause or reverse the deployment operation when the clinician judges that the dilator can not be properly positioned at the target site. WO 2021 / 099646 also discloses designs that can guide the delivery tube to the target site along the penile urethra.

[0012] Embodiments of the present invention provide a simple, compact, efficient and reliable solution to the following needs: one is the operation of the positioning mechanism, and the other is the differential longitudinal movement of the delivery tube concentric element during in-situ visualization and deployment. Accordingly, several embodiments of the present invention provide a delivery instrument that is ergonomically designed. The instrument can achieve precise deployment of the implant with only simple, safe and essentially one-handed operations.

[0013] In several embodiments, the present invention can be embodied as a deployment system for deploying an implant in a patient's body, the system comprising: 1. a deployment driver operable in response to movement of a deployment control element, the movement being specifically from a first position of "implant not deployed" to a second position of "implant partially deployed" and to a third position of "implant fully deployed"; 2. a positioning mechanism configured to prevent movement of the deployment control element from the second position to the third position, the positioning mechanism further comprising: (1) a follower movable to a deployment stop position by movement of the deployment control element from the first position to the second position, thereby preventing continued movement of the deployment control element to the third position; and (2) a positioning release element movable to an unlocked position, movement of the positioning release element acting on the follower to move the follower from the deployment stop position to a deployment release position, which position removes the restriction on the deployment control element to enable movement thereof from the second position to the third position. The positioning release element can be, for example, disposed adjacent to the deployment control element.

[0014] In one embodiment, a deployment system for deploying an implant within a patient's body includes: 1. a deployment driver operable in response to movement of a deployment control element, the movement being from a first position of "implant not deployed" to a second position of "implant partially deployed" to a third position of "implant fully deployed"; and 2. a positioning mechanism configured to prevent movement of the deployment control element from the second position to the third position, the positioning mechanism further including: (1) a follower movable to a deployment stop position by movement of the deployment control element from the first position to the second position, the follower thereby preventing continued movement of the deployment control element to the third position; and (2) a positioning release element movable to an unlocked position, movement of the positioning release element acting on the follower to move the follower from the deployment stop position to a deployment release position, the deployment release position removing the restriction on movement of the deployment control element from the second position to the third position.

[0015] In one embodiment, the follower is movable from the positioning stop position to the deployment stop position; wherein, in the positioning stop position, the follower prevents movement of the positioning release element to the unlocked position. In this case, the positioning release element is substantially prevented from moving from the locked position to the unlocked position unless the follower is moved to the deployment stop position to remove the restriction. In other words, the positioning release element is substantially prevented from moving from the locked position to the unlocked position unless the follower is moved from the positioning stop position to the deployment stop position to remove the restriction.

[0016] The follower can be in the positioning stop position when the deployment control element is in the first position, and can be biased toward the positioning stop position. More generally, the follower can be movable against the bias to the deployment stop position and to the deployment release position.

[0017] The deployment control element can be movable along a trigger axis between the first, second, and third positions; the follower can be movable along a follower axis between the positioning stop position (e.g., the positioning stop position) and the positioning release position (e.g., the deployment release position), the follower axis being perpendicular to the trigger axis; and the positioning release element can be movable along a positioning axis between the locked position and the unlocked position. The positioning axis can be substantially parallel to the trigger axis.

[0018] A trigger ramp movable with the deployment control element, opposable to the follower, and tiltable relative to the trigger axis; such that when the deployment control element is moved along the trigger axis to the second position, the ramp slides relative to the follower, thereby driving the follower to move along the follower axis to the positioning release position. The trigger ramp can be shaped such that when the deployment control element reaches the second position, it can engage the follower, thereby preventing the deployment control element from moving further to the third position. For example, the trigger ramp can include a shoulder extending laterally relative to the ramp surface and opposable to the follower. The deployment control element can be provided with a gripping structure for facilitating an operator to grip the deployment control element and pull it outwardly from the second position to the first position.

[0019] In some embodiments, a deployment system for deploying an implant within a patient's body includes: 1. a deployment driver configured to operate in response to movement of a deployment control element, the movement being from a first position in which the implant is "undeployed", to a second position in which the implant is "partially deployed", and to a third position in which the implant is "fully deployed"; and 2. a positioning mechanism configured to prevent the deployment control element from moving from the second position to the third position, the positioning mechanism including: (1) a follower configured to move to a positioning stop position, thereby preventing the deployment control element from moving further to the third position; and (2) a positioning release element configured to move the follower from the positioning stop position to a positioning release position, the positioning release position being effective to release the deployment control element from the second position to the third position.

[0020] The follower can include a blocking member and an opening, the blocking member being in a blocking opposition with a structure of the positioning release element when the follower is in the positioning stop position, and the opening being in a receiving opposition with the structure when the follower is in the positioning release position. For example, the blocking member and the opening can be disposed in sequence along the follower axis.

[0021] The structure of the positioning release element can include a positioning ramp opposable to the follower and tiltable relative to a positioning axis; such that when the positioning release element is moved along the positioning axis to an unlocking position, the positioning ramp slides relative to the follower, thereby driving the follower to move along the follower axis, first past the activation position and then to the release position, the release position being effective to release the deployment control element from the second position to the third position. The movement of the follower to the release position can suitably disengage the follower from the engagement with the trigger ramp, for example by lifting the follower and completely disengaging it from the shoulder.

[0022] The deployment control element can be provided with a gripping structure for facilitating an operator to grip the deployment control element and pull it outwardly from the second position to the first position.

[0023] Embodiments of the present application can also be embodied as a method of operating an implant deployment instrument, the method comprising: 1. moving a deployment control element of the instrument from a first position in which an implant is "undeployed" to a second position in which the implant is "partially deployed"; 2. acting on a follower of the instrument by the movement of the deployment control element to move the follower to a deployment stop position to prevent further movement of the deployment control element to a third position in which the implant is "fully deployed"; 3. moving a positioning release element of the instrument to an unlocked position, the movement of the positioning release element acting on the follower to move the follower to a deployment release position to thereby release the deployment control element from the second position to the third position.

[0024] In one embodiment, a method of operating an implant deployment instrument (e.g., optionally for treating benign prostatic hyperplasia) can comprise: moving a deployment control element of the instrument from a first position in which an implant is "undeployed" to a second position in which the implant is "partially deployed within the urethra"; wherein the movement of the deployment control element from the first position to the second position acts on a follower of the instrument to move the follower to a deployment stop position to prevent further movement of the deployment control element to a third position in which the implant is "fully deployed within the urethra"; 2. moving a positioning release element of the instrument to an unlocked position; wherein the movement of the positioning release element acts on the follower to move the follower to a deployment release position to thereby release the deployment control element from the second position to the third position.

[0025] The follower can be movable from the positioning stop position to the deployment stop position; wherein in the positioning stop position, the follower prevents movement of the positioning release element to the unlocked position.

[0026] The deployment control element and the positioning release element can suitably act on the follower through respective camming actions. The deployment control element and the positioning release element can be movable along substantially parallel axes.

[0027] The follower can be movable in a direction that is perpendicular to the movement of the deployment control element and the positioning release element. The follower can be biased to bear against the deployment control element and the positioning release element. Similarly, the follower can be movable against the biasing force to the deployment stop position and the deployment release position.

[0028] In some embodiments, the implant deployment instrument involved in the method further comprises a housing and an elongated delivery tube. The elongated delivery tube can comprise an inner element containing an imaging head, a middle element provided with an implant fixation structure, and an outer element comprising an outer sheath that can cooperate with the implant fixation structure. In one embodiment, moving the deployment control element from the first position to the second position comprises retracting the outer element relative to the middle element and the inner element. In some embodiments, moving the positioning release element to the unlocked position comprises retracting the outer element relative to the middle element and the inner element; during which the outer sheath is retracted proximally and over the implant fixation structure to release the implant.

[0029] In some embodiments, a method of operating an implant deployment instrument (e.g., for treating benign prostatic hyperplasia) comprises: 1. moving a deployment control element of the instrument from a first position to a second position; wherein the implant is not deployed in the first position and is partially deployed in the second position; and the act of moving the deployment control element from the first position to the second position causes a follower to move to a deployment stop position that prevents the deployment control element from moving away from the second position; 2. moving a positioning release element of the instrument, which causes the follower to move to a deployment release position that removes the restriction on the deployment control element to move from the second position to a third position in which the implant is fully deployed within the urethra.

[0030] The method can comprise moving the follower from the positioning stop position to the deployment stop position; wherein the follower prevents the positioning release element from moving to the unlocked position in the positioning stop position. The method can comprise causing the deployment control element and the positioning release element to apply a force to the follower via respective camming actions. According to some embodiments, the method can further comprise one or more of: causing the deployment control element and the positioning release element to move along substantially parallel axes; causing the follower to move in a direction that is perpendicular to the direction of movement of the deployment control element and the positioning release element; biasing the follower against the deployment control element and the positioning release element; and / or causing the follower to move against the bias to the deployment stop position and the deployment release position.

[0031] In one embodiment, the implant deployment instrument further comprises a housing and an elongated delivery tube. The elongated delivery tube can comprise an inner element containing an imaging head, a middle element provided with an implant fixation structure, and an outer element comprising an outer sheath that can cooperate with the implant fixation structure.

[0032] In one embodiment, the inner element, the intermediate element, and the outer element are arranged radially in a sequence from inside to outside; wherein moving the deployment control element from the first position to the second position comprises retracting the outer element and the inner element relative to the intermediate element; moving the positioning release element to the unlocked position comprises retracting the outer element relative to the intermediate element and the inner element; and in the process, the outer sheath is retracted proximally and over the implant fixation structure to release the implant.

[0033] In several embodiments, a method of operating an implant deployment instrument includes the following steps: 1. providing an instrument comprising: (1) a housing; (2) an elongated delivery tube comprising delivery tube elements extending from the housing, the delivery tube elements arranged radially in a sequence from inside to outside as: an inner element containing an imaging head, an intermediate element provided with two or more implant fixation structures, and an outer element comprising an outer sheath; wherein the instrument is initially in an undeployed state, and an implant is secured by engagement with the two or more implant fixation structures; 2. retracting the outer element and the inner element relative to the intermediate element by moving a hub carriage to a partial deployment state relative to a portion of the intermediate element hub that is in a fixed relationship with the housing; wherein the hub carriage carries an outer element hub and an inner element hub; 3. releasing a positioning mechanism that was previously preventing the hub carriage from moving from the partial deployment state to a fully deployed state; 4. moving the hub carriage to the fully deployed state to further retract the outer element relative to the intermediate element and the inner element to release the implant.

[0034] During movement of the hub carriage from the undeployed state to the partial deployment state, the inner element hub can be locked relative to the hub carriage. In the context of treating benign prostatic hyperplasia, movement of the inner element hub relative to the housing can be limited when the hub carriage is moved from the partial deployment state to the fully deployed state. The hub carriage can be releasably locked relative to the housing when in the undeployed state. The hub carriage can be driven to move longitudinally by operating a deployment control element. Operating the deployment control element can cause a deployment driver of the implant deployment instrument to move the hub carriage from the undeployed state to the partial deployment state. A positioning mechanism of the deployment driver can prevent the hub carriage from moving from the partial deployment state to the fully deployed state.

[0035] In some embodiments, an apparatus for deploying an implant in a patient's body includes: 1. an elongated delivery tube having delivery tube elements in concentric relationship, the elements being in radial order from inner to outer as an inner element containing an imaging head, a middle element provided with an implant fixation structure, and an outer element comprising an outer sheath; wherein the outer sheath is cooperable with the implant fixation structure, and the inner element and the outer element are retractable relative to the middle element along a longitudinal axis of the delivery tube; 2. a handle at a proximal end of the delivery tube, the handle's housing containing: (1) a hub assembly consisting of an inner element hub, a middle element hub, and an outer element hub, each hub being mounted at a proximal end of a corresponding delivery tube element; (2) a hub carriage longitudinally movable relative to the housing and the middle element hub, and carrying the inner element hub and the outer element hub; the inner element and the outer element are retractable relative to the middle element of the delivery tube by the above movement of the hub carriage; (3) a deployment driver configured to drive the hub carriage to move as above in response to operation of a "housing-external deployment control element". In some embodiments, the hub carriage is a hub shell.

[0036] In some embodiments, an apparatus for deploying an implant in a patient's body includes an elongated delivery tube having delivery tube elements in concentric relationship, the elements being in radial order from inner to outer as an inner element containing an imaging head, a middle element provided with an implant fixation structure, and an outer element comprising an outer sheath; wherein the outer sheath is cooperable with the implant fixation structure, and the inner element and the outer element are retractable relative to the middle element along a longitudinal axis of the delivery tube. The apparatus further includes a handle at a proximal end of the delivery tube. The handle's housing can contain: 1. a hub assembly consisting of an inner element hub, a middle element hub, and an outer element hub, wherein the inner element hub is mounted at a proximal end of the delivery tube inner element, the middle element hub is mounted at a proximal end of the delivery tube middle element, and the outer element hub is mounted at a proximal end of the delivery tube outer element; 2. a hub carriage configured to be longitudinally movable relative to the housing and the middle element hub, and carrying the inner element hub and the outer element hub, the inner element and the outer element being retractable relative to the middle element of the delivery tube by the above longitudinal movement of the hub carriage; 3. a deployment driver configured to drive the hub carriage to move as above in response to operation of a "housing-external deployment control element".

[0037] In several embodiments, the hub carriage is movable proximally along a longitudinally extending retraction path relative to the housing and the intermediate element hub by action of the deployment driver; the movement trajectory of the hub carriage encompasses three positions, specifically: from an "undeployed position", via an "intermediate partial deployment position", to a "fully deployed position". The undeployed position: the outer sheath is disposed opposite the implant fixation structure, and the outer sheath is in a distally advanced position relative to the implant fixation structure; the intermediate partial deployment position: the outer element is retracted proximally from the distally advanced position, but remains disposed opposite the implant fixation structure; the fully deployed position: the outer sheath is retracted proximally and passes over the implant fixation structure.

[0038] The outer element hub and the inner element hub are movable proximally with the hub carriage from the undeployed position to the partial deployment position. In this case, the outer element hub and the inner element hub are also movable distally with the hub carriage along the retraction path from the partial deployment position to the undeployed position.

[0039] When the hub carriage is moved from the partial deployment position to the fully deployed position, the outer element hub is movable proximally with the hub carriage relative to the inner element hub. In this case, the outer element hub can be fixed relative to the hub carriage, while the inner element hub can be releasably locked relative to the hub carriage. For example, a stop structure, which is fixed relative to the housing, can be located on the retraction path proximally of the inner element hub to prevent the inner element hub from moving proximally beyond the partial deployment position of the hub carriage. This would cause the inner element hub to be unlocked from the hub carriage, while allowing the hub carriage and the outer element hub to continue to move proximally from the partial deployment position to the fully deployed position.

[0040] When the hub carriage is in the undeployed position, it can be releasably locked relative to the housing, and this locked state can be released by operating the deployment control element. In one embodiment, when the hub carriage is in the undeployed position, it can be releasably locked relative to the housing, wherein the hub carriage is configured to be unlocked by operating the deployment control element.

[0041] The deployment driver preferably includes a detent mechanism and a detent release element; wherein the detent mechanism is configured to prevent the hub carriage from moving from the partial deployment position to the fully deployed position, and the detent release element is operable to release the detent mechanism, thereby allowing the hub carriage to move from the partial deployment position to the fully deployed position. For example, when the deployment control element moves and acts on the deployment driver to move the hub carriage from the undeployed position to the partial deployment position, the detent release element can thereby acquire the ability to release the detent mechanism. In this regard, when the hub carriage is in the undeployed position, the deployment control element can prevent the detent release element from moving.

[0042] In some embodiments, an apparatus for deploying an implant within a patient's body includes a delivery tube and a handle, wherein the delivery tube comprises: an inner member provided with an imaging head; an intermediate member provided with two or more implant fixation structures; and an outer member provided with an outer sheath. The inner member, the intermediate member, and the outer member are arranged in concentric relation, and the inner member and the outer member are movable relative to the intermediate member along a longitudinal axis of the delivery tube. The handle can include a housing, a hub assembly, a hub carriage, and a deployment driver, each of which is described in detail as follows: the hub assembly is comprised of an inner member hub, an intermediate member hub, and an outer member hub; the inner member hub is mounted to a proximal end of the inner member of the delivery tube, the intermediate member hub is mounted to a proximal end of the intermediate member of the delivery tube, and the outer member hub is mounted to a proximal end of the outer member of the delivery tube; the hub carriage is configured to be longitudinally movable relative to the housing and carries the inner member hub and the outer member hub; the inner member and the outer member are movable relative to the intermediate member of the delivery tube by longitudinal movement of the hub carriage; and the deployment driver is configured to drive the hub carriage to move longitudinally in response to operation of a deployment control system.

[0043] The outer member hub, the intermediate member hub, and the inner member hub can be arranged in proximal order along the hub carriage. The hub carriage can include a distal portion that supports the outer member hub, a proximal portion that supports the inner member hub, and a longitudinal intermediate portion that connects the distal portion and the proximal portion and extends around the intermediate member hub. The intermediate member hub is suitably sandwiched between the outer member hub and the inner member hub and can be at least partially housed within the hub carriage.

[0044] The intermediate member hub can be provided with at least one support that extends outwardly beyond the hub carriage to secure the intermediate member hub from moving relative to the housing. In this case, a side wall of the hub carriage can be provided with a longitudinally extending slot that receives the laterally extending support of the intermediate member hub to allow the hub carriage to move relative to the intermediate member hub. Such a slot is suitably provided in the form of a proximally open slot.

[0045] The deployment driver can include a gear set that acts between the deployment control member and the hub carriage. In this case, the hub carriage can be provided with a longitudinally extending rack structure that engages with one of the gears of the gear set of the deployment driver. For example, the rack structure can be provided on an arm that extends proximally from the hub carriage. The arm can be laterally offset relative to a central longitudinal axis that extends proximally from the delivery tube into the housing, in which case the rack structure can be directed toward the axis.

[0046] In one embodiment, the inventive concept encompasses a corresponding method of operating an implant deployment instrument; the instrument having elongated delivery tube elements extending from a housing in concentric relation, the elements being in radial order from inner to outer: an inner element containing an imaging head, a middle element provided with implant retaining structures, and an outer element containing an outer sheath, the outer sheath being cooperable with the implant retaining structures. In embodiments, the method includes the steps of: 1. placing the instrument in an undeployed state: the outer sheath is disposed opposite the implant retaining structures, and is in a distally advanced position relative to the implant retaining structures, the implant being retained by engagement with the retaining structures; 2. withdrawing the outer element and the inner element relative to the middle element to a partially deployed state: by moving a hub carriage of the instrument relative to a "middle element hub in fixed relation to the housing", the hub carriage carrying an outer element hub and an inner element hub; 3. moving the hub carriage carrying the outer element hub relative to the middle element hub: to further withdraw the outer element relative to the middle element to a fully deployed state; the outer sheath is withdrawn proximally and over the implant retaining structures to release the implant.

[0047] In embodiments, a method of operating an implant deployment instrument includes placing the implant deployment instrument in an undeployed state. The implant deployment instrument includes an elongated delivery tube having elongated delivery tube elements extending from a housing in concentric relation; the delivery tube elements being in radial order from inner to outer: an inner element containing an imaging head, a middle element provided with implant retaining structures, and an outer element containing an outer sheath, the outer sheath being cooperable with the implant retaining structures. The undeployed state can include the outer sheath being disposed opposite the implant retaining structures, and being in a distally advanced position relative to the implant retaining structures, thereby retaining an implant engaged with the implant retaining structures. The method can include the steps of: 1. withdrawing the outer element and the inner element relative to the middle element to a partially deployed state by moving a hub carriage of the implant deployment instrument relative to a "middle element hub in fixed relation to the housing", the hub carriage carrying an outer element hub and an inner element hub; 2. moving the hub carriage carrying the outer element hub relative to the middle element hub and the inner element hub to withdraw the outer element relative to the middle element and the inner element to a fully deployed state. In the fully deployed state, the outer sheath is withdrawn proximally and over the implant retaining structures to release the implant (e.g., in a urethra).

[0048] In embodiments, the method includes moving the outer element hub and the inner element hub proximally with the hub carriage to move the hub carriage to a partially deployed state. The method can include moving the outer element hub proximally with the hub carriage relative to the inner element hub to move the hub carriage to a fully deployed state; wherein the fully deployed state is for releasing the implant in a urethra.

[0049] In some embodiments, the hub carriage can be releasably locked relative to the housing when in the undeployed state. Similarly, the inner element hub can be locked relative to the hub carriage during movement of the hub carriage from the undeployed state to the partially deployed state. Movement of the inner element hub relative to the housing during movement of the hub carriage from the partially deployed state to the fully deployed state can be prevented, thereby unlocking the inner element hub from the hub carriage.

[0050] In some embodiments, movement of the hub carriage into the partially deployed state also causes the outer element hub to move proximally with the hub carriage relative to the inner element hub. Movement of the hub carriage into the fully deployed state also causes the outer element to move proximally with the hub carriage relative to the inner element hub. Operation of the deployment control element releases the hub carriage from its locked state with the housing. In such embodiments, operation of the deployment control element causes the deployment driver of the instrument to drive the hub carriage from the undeployed state to the partially deployed state. In some embodiments, a detent mechanism of the deployment driver prevents movement of the hub carriage from the partially deployed position to the fully deployed position. In such embodiments, operation of the deployment control element causes a detent release element to gain the ability to release the detent mechanism. For example, depression of the detent release element releases the detent mechanism, thereby allowing movement of the hub carriage from the partially deployed position to the fully deployed position. In one embodiment, operation of the deployment control element causes a gear set of the deployment driver to engage, which can engage an extension rack structure of the hub carriage to control movement of the hub carriage. Operation of the deployment control element can effect movement of the hub carriage from the undeployed state to the partially deployed state and from the partially deployed state to the undeployed state.

[0051] In some embodiments, the method can include moving the outer element hub proximally with the hub carriage to move the hub carriage into a partially deployed state. The method can include moving the outer element hub proximally with the hub carriage relative to the inner element hub to move the hub carriage into a fully deployed state. The method can include locking the inner element hub relative to the hub carriage during movement of the hub carriage from the undeployed state to the partially deployed state. The method can include preventing movement of the inner element hub relative to the housing during movement of the hub carriage from the partially deployed state to the fully deployed state. The method can include releasably locking the hub carriage relative to the housing when the hub carriage is in the undeployed state. The method can include operating the deployment control element to drive longitudinal movement of the hub carriage. The method can include operating the deployment control element to cause a deployment driver of the implant deployment instrument to move the hub carriage from the undeployed state to the partially deployed state. The method can include using a detent mechanism of the deployment driver to prevent movement of the hub carriage from the partially deployed position to the fully deployed position. The deployment control element can move a detent release element to release the detent mechanism. The method can include pressing the detent release element to release the detent mechanism to allow movement of the hub carriage from the partially deployed position to the fully deployed position. The method can include operating the deployment control element to cause a gear set of the deployment driver to engage, the gear set being engageable with an extended rack structure of the hub carriage to control movement of the hub carriage. The method can include operating the deployment control element to effect movement of the hub carriage from the undeployed state to the partially deployed state and / or from the partially deployed state to the undeployed state.

[0052] According to some embodiments, the inventive concept can also be embodied by an implant delivery instrument comprising: 1. an elongate flexible implant delivery element; 2. a housing from which the delivery element extends; 3. a steering system within the housing and acting on the delivery element, the system being operable by a user of a steering lever to bend the delivery element along its length; wherein the steering lever is pivotable relative to a pivot axis provided within the housing; 4. mutually engageable locking structures within the housing, comprising a first locking structure that pivots with the steering lever, and a second locking structure that is fixed relative to the housing. The steering lever is movable from a locked position to an unlocked position relative to the pivot axis; in the locked position, the locking structures are engaged with each other to limit the pivot movement of the steering lever; in the unlocked position, the locking structures are disengaged to allow the pivot movement of the steering lever. The steering lever can be biased to move away from the pivot axis towards the locked position.

[0053] For example, the second locking structure can be integral with the housing and provided on an inner surface of the housing. The second locking structure can be arcuate about the pivot axis; in this case, a centre of curvature of the second locking structure can coincide with the pivot axis.

[0054] The steering lever is movable along a locking axis toward or away from the pivot axis, the locking axis intersecting the second locking structure. The second locking structure can be disposed between the pivot axis and the outer end of the steering lever.

[0055] The steering wire can extend from a steering dial that pivots with the steering lever into the delivery element. In this case, the steering lever can be movable relative to a hub portion of the steering dial along an axis that intersects the pivot axis; but the steering lever is limited in its movement relative to the hub portion about the pivot axis. BRIEF DESCRIPTION OF DRAWINGS

[0056] For a better understanding of the various embodiments of the present application, reference will now be made to the accompanying drawings in which:

[0057] Figure 1 A side view of a dilator according to the present application in an expanded state;

[0058] Figure 2 A cross-sectional view of a patient's prostate, wherein Figure 1 The dilator is shown positioned within the prostatic urethra; the dilator treats benign prostatic hyperplasia by exerting outward radial pressure on the prostatic urethra wall, thereby effecting dilation.

[0059] Figure 3 A side view of a delivery instrument according to the present application, the instrument comprising a handle and a delivery tube;

[0060] Figure 4 An enlarged detail perspective view of a distal portion of the delivery tube; at this stage of the instrument, the distal portion houses an undeployed dilator;

[0061] Figure 5 corresponds to Figure 4 but the instrument is shown at a first stage of deployment, the dilator being in a partially deployed state;

[0062] Figure 6 A schematic view of an image captured by an imaging chip of the instrument, at a first stage of deployment shown in Figure 5, the instrument being in a state of use;

[0063] Figure 7 corresponds to Figure 4 and Figure 5, but the instrument is shown at a second stage of deployment, the dilator being in a fully deployed state;

[0064] Figure 8a , Figure 8b and Figure 8c are cross-sectional side views of a distal portion of the delivery tube, corresponding respectively to Figure 4 , Figure 5 and Figure 7 the stages of deployment of the instrument shown in Figures 5 and 6.

[0065] Figure 9 isFigure 3 side view of the handle housing component half-shell;

[0066] Figure 10 corresponding to the half-shell shown with the handle components assembled; Figure 9

[0067] Figure 11 schematic perspective view showing the device in use, with the distal end portion of the delivery tube advanced into the prostatic urethra, and the handle held and operated by the user;

[0068] Figure 12 exploded perspective view of the delivery tube concentric element;

[0069] Figure 13 enlarged perspective view of the proximal hub portion of the inner delivery tube element shown; Figure 12

[0070] enlarged cutaway distal perspective view of the camera tip connectable to the distal end of the inner delivery tube element shown; Figure 14 Figure 12 enlarged cutaway proximal perspective view of the camera tip shown;

[0071] Figure 15 Figure 14 enlarged cutaway distal perspective view of the steering tip at the distal end of the intermediate delivery tube element shown;

[0072] Figure 16 enlarged distal perspective view of the steering tip shown; Figure 12

[0073] Figure 17 enlarged proximal perspective view of the intermediate delivery tube element shown, with the proximal hub portion in engagement with the handle housing; Figure 16

[0074] enlarged perspective view of the proximal hub portion of the outer delivery tube element shown; Figure 18 Figure 12 exploded perspective view of the hub shell connecting to the proximal hub portion of the outer delivery tube element shown;

[0075] Figure 19a Figure 19b cutaway perspective view of the proximal hub portion of the intermediate delivery tube element shown, with the proximal hub portion in engagement with the handle housing; Figure 18

[0076] sequence of cutaway perspective views showing the device in different stages of deployment; Figure 20 Figure 12

[0077] Figures 21a to 21d Figure 19a Figure 19b ​​​​​​​​​​the process of movement of the hub shell relative to the handle housing;

[0078] Figures 22a to 22d a sequence of cutaway perspective views showing the process of movement of the external control elements relative to the handle housing between different stages of deployment of the instrument;

[0079] Figures 23a to 23d a sequence of side views showing Figures 22a to 22d the relative movement and interaction between the control elements to achieve the positioning function of the instrument; and

[0080] Figure 24a and Figure 24b a perspective view showing the operation of the instrument steering mechanism.

[0081] The drawings are not limiting, and represent only some embodiments of the application. Elements from different drawings can be combined with each other. DETAILED DESCRIPTION

[0082] To make several embodiments of the application more readily understood, reference will first be made to Figure 1 The figure shows an expandable implant or dilator 10 suitable for use in embodiments of the application. Figure 1 The dilator 10 shown is merely an example: the delivery instrument to be described below can be adapted for use with other implants, or can be adapted for use with other implants.

[0083] In several embodiments, the dilator 10 comprises a continuous sinusoidal wave of a nickel-titanium alloy wire connected at opposite ends by sleeves 12. Upon release, the dilator 10 can self-expand from a radially compressed state for stowage to a radially expanded state for deployment by elastic recovery, as shown in Figure 1 In particular, the nickel-titanium alloy wire ring of the dilator 10 can function by virtue of super-elastic shape memory properties: in the compressed state, the dilator 10 can exert an outward radial force on the surrounding human structure in which it is implanted, particularly the prostatic urethra.

[0084] In one embodiment, the proximal end of the dilator 10 comprises three proximal prongs, each with a proximal apex 14; and the distal end comprises three distal prongs, each with a distal apex 16. The proximal and distal apices 14, 16 can be connected alternately circumferentially by longitudinal struts 18. Each strut 18 can be outwardly convex in shape, which gives the dilator 10 a barrel-like appearance in profile view.

[0085] In the radially compressed state, the dilator 10 can be collapsed to a degree of thinness sufficient to enable it to be advanced along the patient's penile urethra with only slight discomfort. The dilator 10 can be delivered to the prostatic urethra in the collapsed state described above, and then released and self-expanded in situ.

[0086] Referring now to the drawings in detail Figure 2 , FIG. 2 illustrates the condition in which the dilator 10 is used within the prostate 20 to treat the symptoms of benign prostatic hyperplasia, in accordance with one embodiment. Specifically, the dilator 10 is positioned within the prostatic urethra 22 of the prostate 20, between the bladder neck 24 and the external sphincter 26. When in this longitudinal position, the dilator 10 exerts outward radial forces on the lobes of the prostatic urethra 22, thereby relieving the resistance to the flow of urine out of the bladder.

[0087] In various embodiments, it is noted that care is taken to ensure that the dilator 10 is in the correct longitudinal position between the bladder neck 24 and the external sphincter 26 prior to deployment. In this regard, it is undesirable to position the dilator 10 too close to either the bladder neck 24 or the external sphincter 26, as muscle activity in either of these locations can cause the dilator 10 to move along the urethra over time, or into the bladder.

[0088] In several embodiments, the dilator 10 is also angularly positioned to ensure that the verumontanum 28 and vas deferens 30 are not obstructed by the undulating wire of the dilator 10, thereby preserving the sexual function of the patient. In addition, the longitudinal struts 18 of the dilator 10 are oriented to conform to the individual lobes of the prostate 20, thereby exerting outward radial forces on each lobe to maintain an unobstructed passageway between the bladder neck 24 and the external sphincter 26.

[0089] Referring next to Figure 3 , one embodiment of an instrument 32 for deploying a self-expanding implant or dilator 10 includes a proximal handle 34 that acts on a flexible delivery tube 36 extending distally therefrom. In an initial state, as shown in Figure 4 and Figure 8a , the dilator 10 is sheathed in a radially compressed state within a distal portion of the delivery tube 36, ready for insertion and delivery to a target deployment site within the prostatic urethra.

[0090] As will be explained below, and as shown in Figure 8a , 8b and 8c, one embodiment of the delivery tube 36 includes three flexible tubular elements in concentric, longitudinally sliding relationship, specifically: an outer element 38, which is an outer sheath; an inner element 40, which is an imaging sheath; and an intermediate element 42, which is a steering sheath, disposed within an annular gap formed between the outer sheath and the imaging sheath.

[0091] A user of the instrument 32 can steer the delivery tube 36 during navigation along the urethra to the target site by operating a steering lever 44 on the handle 34. Operation of the steering lever 44 acts on the intermediate element 42 to deflect the distal portion of the delivery tube 36 relative to the proximal portion thereof.

[0092] In several embodiments, the internal element 40 of the delivery tube 36 is provided with an imaging system (e.g., an imaging head) at its distal end, which provides the user with an image of the urethra; the image is captured on a longitudinal axis radially inward of the dilator 10 within the distal portion of the delivery tube 36. In this example (e.g.) Figure 4 and Figure 8a As shown, the camera tip 46 (or other imaging or sensing technology) forms the distal end of the internal element 40, with its image acquisition and illumination components adjacent to the flushing conduit, initially protruding distally from the external element 38. This ensures that the delivery tube 36 obtains the best possible field of vision when navigating to the anatomical structure before the dilator 10 is deployed. However, in other examples, the distal end of the internal element 40 may be substantially flush with the distal end of the external element 38, or even slightly recessed proximally, provided sufficient field of vision is maintained.

[0093] Before reaching the deployment location, expander 10 may be enclosed within the distal portion of delivery pipe 36 by external element 38, as shown in Figures 4 and 8a. Since the deployment of expander 10 has not yet begun at this point, this stage or initial undeployed state will be referred to as the "zero deployment stage" in the following description.

[0094] In one embodiment, when the expander 10 is in or near the deployment position, the user operates the deployment control element (i.e., the trigger 48 outside the handle 34); this trigger acts on the delivery tube 36, causing the expander 10 to partially detach from its outer casing, as shown in Figure 5. Figure 8b As shown. In the following description, this stage or intermediate state will be referred to as the "first deployment stage". At this time, the imaging system of the camera end 46 can capture an image of the distal end of the dilator 10 relative to the structures surrounding the prostatic urethra.

[0095] During the first deployment phase, the deployment trigger 48 is reversible, allowing the device 32 to revert to the zero deployment phase. Therefore, if the user decides to significantly reposition the expander 10 or chooses to abort the procedure, the expander 10 can be put back into its sheath.

[0096] Figure 8b This demonstrates how, in a partial deployment configuration during the "first deployment phase," the outer element 38 and the inner element 40 (including the camera tip 46) are pulled proximally relative to the intermediate element 42, and consequently also proximally relative to the expander 10 supported by the intermediate element 42. Therefore, advantageously, in the pulled-back position, the imaging device of the camera tip 46 can clearly observe the expander 10 from a viewpoint inside the expander 10, with the adjacent anatomical structures as a background. The pulled-back outer element 38 does not enter the field of view of the imaging device.

[0097] The prongs at the distal tip 14 of the dilator 10 can contact the lobes of the prostate 20, so that the user can observe and confirm the position of the dilator 10 relative to the surrounding structures of the prostatic urethra 22 before full deployment. Advantageously, this design allows the user to check the accuracy of the position of the dilator 10 before full deployment.

[0098] To illustrate this, Figure 6 is a schematic representation of the image captured by the imaging device of the camera tip 46 when the outer element 38 is in the partially deployed position. The image shows that the distal tip 14 of the dilator 10 is aligned with and in contact with the lateral lobes surrounding the prostatic urethra 22. In particular, the image shows that the posterior prongs 50 of the dilator 10 are wrapped around or straddle the verumontanum 28, while the two anterior prongs 54 of the dilator 10 are oriented to abut the anterior lobes 56.

[0099] It is clear that the image provided by the imaging device of the camera tip 46 to the user has the significant advantage of simultaneously presenting two types of position information: the longitudinal position of the dilator 10 relative to anatomical structures such as the verumontanum 28 and the bladder neck 24, and the angular position of the dilator 10 relative to the verumontanum 28 and the prostate lobes 56. This helps to accurately position the dilator 10 within the prostatic urethra 22.

[0100] From Figure 5, Figure 6 and Figure 8b It can also be noted that the barrel-like profile of the dilator 10 described above causes the distal tip 14 to converge towards the central longitudinal axis 58 when the camera tip 46 of the inner element 40 is retracted inside the dilator 10. This brings the distal tips 14 into contact or close contact with each other, so that they are in a prominent central position in the field of view of the user, thereby becoming an effective aiming point for the user.

[0101] In one embodiment, when the user confirms that the dilator 10 is accurately positioned at the deployment site, the user can operate the deployment trigger 48 to cause the dilator 10 to fully exit the sheath to complete deployment, as shown in Figure 7 and Figure 8c In the following description, this stage or final state will be referred to as the "second deployment stage". After the outer element 38 is pulled back to cause the dilator 10 to fully exit the sheath, the dilator 10 will radially expand at the target site and thereby be released from the delivery tube 36 to enter the deployed state within the prostatic urethra 20. In the example of the present application described below, the inner element 40 does not follow the further pullback of the outer element 38, so that the angle of view of the camera tip 46 remains fixed from the first deployment stage to the second deployment stage.

[0102] A positioning mechanism prevents inadvertent deployment of the dilator 10 by locking operation of the deployment trigger 48 (which otherwise could result in full sheath removal of the dilator 10). Specifically, during the first deployment phase, the user must deliberately depress a positioning release element (e.g., the positioning button 60) before the deployment trigger 48 can be operated to unsheathe and complete deployment of the dilator 10 during the second deployment phase.

[0103] The positioning button 60 is inoperable when the instrument 32 is in the zero deployment phase. The positioning button 60 becomes operable after the deployment trigger 48 is operated to place the instrument 32 in the first deployment phase. The user then separately and deliberately operates the positioning button 60 by finger action to release the deployment trigger 48 for further movement, thereby placing the instrument 32 in the second deployment phase.

[0104] During partial and full unsheathing of the dilator 10, the instrument 32 is fixed in axial and angular position relative to the handle 34, in addition to the steering action, to ensure accuracy of the dilator 10 positioning at the deployment site. The angular position of the dilator 10 relative to the imaging device of the camera tip 46 is also fixed.

[0105] Referring next to Figure 9 and Figure 10 In one embodiment, the handle 34 includes a hollow housing 62 of molded polymer material that is divided along a central longitudinal plane into two halves 64. The halves 64 are generally mirror images of each other about the planar interface between them. The halves 64 are secured together by a plurality of screws that are spaced apart from each other and from components disposed within the housing 62.

[0106] On the concave inner side of the halves 64, there are integrally molded positioning and guide structures 66. These structures are used to support and guide the movement of various components disposed within and extending from the housing 62, as described below. As shown in Figure 10 These components are grouped into subassemblies, including, as shown in FIG. 2, a hub assembly 68 at the proximal end of the delivery tube 36, a placement system 70 that acts on the hub assembly 68 to drive relative longitudinal movement of a particular elongated element of the delivery tube 36, and a steering system 72 that deflects the distal portion of the delivery tube 36 during navigation to the placement site in the patient. The hub of the hub assembly 68 that is driven by the placement system 70 is movable along a central longitudinal axis 58 relative to the housing 62. The central longitudinal axis 58 extends within the housing 62 and is aligned with the proximal end of the delivery tube 36.

[0107] From the outside, the housing 62 of the handle 34 is provided with a narrow waist 74 that is approximately elliptical in cross-section, and with an enlarged proximal portion 76; the user-operable control elements of the deployment system 70 and of the steering system 72 project from inside the handle 34 through corresponding openings in the housing 62 at the proximal portion 76.

[0108] In particular, in one embodiment, the control elements of the deployment system 70 are a deployment trigger 48 and a positioning button 60, which are arranged side by side with respect to each other. The deployment trigger 48 and the positioning button 60 are movable into and out of the housing 62 along respective operating axes, i.e. a trigger axis 78 and a positioning axis 80, which are both perpendicular to the central longitudinal axis 58 of the housing 62. In the present example, the trigger axis 78 and the positioning axis 80 are close to each other and are both straight and parallel.

[0109] Conversely, in one embodiment, the control element of the steering system 72 is a steering lever 44, which is pivotable with respect to the housing 62 about a pivot axis 82 inside the housing 62. The pivot axis 82 is perpendicular to the central longitudinal axis 58 of the housing 62 and to the trigger axis 78 and to the positioning axis 80. The steering lever 44 is also movable into and out of the housing 62 along a locking axis 84 that intersects the pivot axis 82, as described below, in such a way as to respectively unlock and lock the pivotal movement of the steering lever 44.

[0110] Figure 11 It is shown that, in several embodiments, the instrument 32 is designed to be primarily operated by a single hand and allows the user to choose to hold and operate it with either the left or the right hand, according to preference. Therefore, the control elements of the deployment system 70 and of the steering system 72, i.e. the deployment trigger 48, the positioning button 60 and the steering lever 44, are arranged on the central longitudinal plane that separates the two half-shells 64 of the housing 62 and are substantially symmetrical about this plane.

[0111] The instrument 32 is designed to be held in a pistol grip by the user in a tilted or upright position. When held in this way, the user's index finger is aligned with the deployment trigger 48 and with the positioning button 60 of the deployment system 70, thus allowing easy operation of these two components. The user can also choose to operate the positioning button 60 with the index finger and the deployment trigger 48 with the middle finger. Conversely, the user's thumb is aligned with the steering lever 44 of the steering system 72, thus allowing easy operation. The steering lever 44 projects from the other side of the housing 62 and is distributed opposite the deployment trigger 48 and the positioning button 60 around the central longitudinal axis 58 of the housing 62.

[0112] The user's other fingers wrap around the narrow waist 74 of the housing 62 to hold the instrument 32 in the palm, with the enlarged proximal portion 76 of the housing 62 supported above the palm. Thus, when the delivery tube 36 is initially extended from the housing 62, it is oriented generally downward in a distal direction; but it can thereafter be bent along its length so that its distal portion can follow a desired insertion path into the patient's prostatic urethra through the urethra of the penis.

[0113] The housing 62 also includes a flushing port 86 (e.g., a luer fitting) at the distal end of the narrow waist 74 of the housing 62 for delivering flushing fluid from an external source into the delivery tube 36. The housing 62 also includes a power and data port 88 at a distal location opposite the flushing port 86. The power and data port 88 enables the transfer of power from an external source to the imaging electronics of the delivery tube 36 and the transfer of image data collected by the imaging electronics to an external display.

[0114] As previously mentioned, the delivery tube 36 includes three flexible tubular elements in concentric, longitudinally sliding relationship, as follows: an outer element 38 formed of an outer sheath 90; an inner element 40 formed of an imaging sheath 92; and an intermediate element 42 formed of a steering sheath 94 disposed in an annular gap between the outer sheath 90 and the imaging sheath 92. Figure 12 The three elements 38, 40, 42 are shown separately. As will be apparent, the sheaths 90, 92, 94 are fixed to corresponding hubs 96, 98, 100 at or near the proximal ends of the corresponding elements 38, 40, 42.

[0115] The intermediate element 42 is fixed relative to the handle 34 and cannot move axially; but the outer element 38 and the inner element 40 can move axially relative to the intermediate element 42 and the handle 34, as will be explained below. The hubs 96, 98, 100 lock the corresponding elements 38, 40, 42 into the system, thereby limiting the direction of movement of the outer element 38 and the inner element 40 to axial movement along a fixed path aligned with the central longitudinal axis 58 of the handle 34, which movement is controlled by the user operating the deployment trigger 48 of the handle 34.

[0116] In the present example, all of the sheaths 90, 92, 94 are tubular; but in principle, the imaging sheath 92 could also be a solid, flexible rod with wires, cables or conduits embedded within it (e.g., in parallel channels extruded into the profile). In either case, such wires or cables must be isolated from each other and from the flushing fluid flow that can be delivered along the imaging sheath 92.

[0117] In some embodiments, the sheaths 90, 92, 94 are as thin as possible to ensure that the overall diameter of the delivery tube assembly is small enough. For example, in the described application, the outer diameter needs to be less than 16 Fr (5.33 mm). As non-limiting examples, the wall thickness of each sheath is in the following ranges - outer sheath 90: 0.159 mm to 0.254 mm, with common values including 0.160 mm, 0.165 mm, 0.170 mm, 0.175 mm, 0.180 mm, 0.185 mm, 0.190 mm, 0.195 mm, 0.200 mm, 0.210 mm, 0.220 mm, 0.230 mm, 0.240 mm, 0.250 mm, etc.; steering sheath 94 (proximal main section): 0.394 mm to 0.464 mm, with common values including 0.400 mm, 0.410 mm, 0.420 mm, 0.430 mm, 0.440 mm, 0.450 mm, 0.460 mm, etc., leaving about 0.61 mm for accommodating the dilator 10 and ensuring clearance. Imaging sheath 92 (area below the dilator 10): 0.114 mm to 0.159 mm, with common values including 0.120 mm, 0.130 mm, 0.140 mm, 0.150 mm, etc.

[0118] In some embodiments, the sheaths 90, 92, 94 are flexible enough to achieve a deflection angle of, for example, 40° to 90° (e.g., 45°, 50°, 60°, 70°, 80°, etc., and any value within the range) along their full length to adapt to the anatomical curvature of the male urethra and reach the prostatic urethra 22 smoothly. In particular, the sheaths 90, 92, 94 are designed to bend along their length and deform naturally with the urethra as they extend from the insertion point at the urethral meatus to the bladder neck 24. Thus, in some embodiments, each sheath 90, 92, 94 is provided with a flexible steering section that is driven by a steering mechanism controlled by the steering system 72 at the proximal end of the delivery tube 36 and the handle 34 to achieve active deflection. In addition, each sheath 90, 92, 94 can also be provided with a flexible proximal section that is used to passively adapt to the deformation caused by the anatomical structure, such as the curvature of the penile urethra.

[0119] For example, one or more of the sheaths 90, 92, 94 can adopt a braided or coiled structure to be flexible enough to adapt to the curvature of the anatomical structure and meet the deflection requirements of the imaging tip. At the same time, the structure of the delivery tube 36 also needs to have sufficient axial and circumferential stiffness to resist the forces generated during insertion, steering, navigation, and sheathing of the dilator 10, and if necessary, to resist the force of re-sheathing the dilator 10. As described below, to achieve the above objectives, any one or all of the sheaths 90, 92, 94 can be designed to have specific stiffness and bending characteristics.

[0120] In several embodiments, the torsional stiffness of the sheaths 90, 92, 94 needs to be great enough to achieve angular alignment of the dilator 10 about the central longitudinal axis 58. In this regard, the circumferential or angular position of the dilator 10 within the prostatic urethra 22 is controlled by the overall rotation of the handle 34. In one embodiment, the handle 34 imparts a torque to the sheaths 90, 92, 94 to which it is connected. It is noted that the circumferential angular movement of the sheaths 90, 92, 94 relative to the handle 34 is fixed, and thus cannot rotate independently of the handle 34.

[0121] The simplest and most basic form of a sheath is a single extrusion made of a polymeric material having a specific stiffness value. However, a single material extrusion with a necessarily thin wall thickness can kink or buckle when subjected to deflection forces from the steering mechanism, axial compression forces, or other bending loads. For this reason, any one or all of the sheaths 90, 92, 94 can benefit from being designed with differential material properties along its length. This can allow the individual sheaths 90, 92, 94, as well as the laminated sheath assembly of the delivery tube 36, to possess the desired design characteristics to access the prostatic urethra 22, navigate through the anatomy, and manipulate and support the dilator 10.

[0122] Examples of properties that can be tailored along the length of the sheaths 90, 92, 94 include flexibility, kink resistance, trackability, the ability to impart an axial force parallel to the longitudinal axis 58 (i.e., "pushability"), and the ability to impart a torque about the longitudinal axis 58 (i.e., "torqueability"). These properties can be tailored, for example, by one or more of the following:

[0123] Mixed extrusion, i.e., joining two or more materials of different stiffness or durometer properties together by a reflow or bonding process.

[0124] A fully braided sheath, i.e., a tailored multi-layer braided sheath with a braided pitch design or braid angle tailored to the desired and / or required stiffness properties. The braid structure can remain uniform along the length of the sheath.

[0125] A fully braided coiled sheath, i.e., a tailored multi-layer coiled sheath with a coiled pitch design or coil angle tailored to the desired and / or required stiffness properties. The coil structure can remain uniform along the length of the sheath.

[0126] A hybrid braided sheath, i.e., a custom multi-layer braided sheath, in which the braided pitch design or angle is customized according to the desired and / or required stiffness characteristics. In this case, however, the braided structure can vary along the length of the sheath. For example, at different longitudinal locations where the sheath requires more or less flexibility, tighter or looser braiding, or braided structures of higher or lower density can be employed. The angle of the braided wire relative to the central longitudinal axis 58 can also be adjusted to vary the flexibility of the sheath along its length.

[0127] A hybrid braided sheath, i.e., a custom multi-layer braided sheath, in which the braided pitch design or angle is customized according to the desired and / or required stiffness characteristics. In this case, however, the braided structure can vary along the length of the sheath. For example, at different longitudinal locations where the sheath requires more or less flexibility, tighter or looser braiding, or braided structures of higher or lower density can be employed. The angle of the braided wire relative to the central longitudinal axis 58 can also be adjusted to vary the flexibility of the sheath along its length.

[0128] A hybrid braided sheath, i.e., a custom multi-layer braided sheath, in which the braided pitch design or angle is customized according to the desired and / or required stiffness characteristics. In this case, however, the braided structure can vary along the length of the sheath. For example, at different longitudinal locations where the sheath requires more or less flexibility, tighter or looser braiding, or braided structures of higher or lower density can be employed. The angle of the braided wire relative to the central longitudinal axis 58 can also be adjusted to vary the flexibility of the sheath along its length.

[0129] In all of the above examples, when a particular region of the sheath requires more or less flexibility, this can be achieved by backflowing a different hardness of polymer outer layer in the braided or coiled wire. In addition, adjusting the thickness of this polymer outer layer can also be used to vary the characteristics of the corresponding region of the sheath to meet the flexibility requirements at different locations.

[0130] In various embodiments, the rigid molded tip segment can be attached to the braided sheath by a backflow, adhesive, or overmolding process.

[0131] In combination Figure 13 As can be seen, the inner member 40 includes the imaging sheath 92 and an inner member hub 98 that is fixed to the imaging sheath 92 proximate the proximal end of the imaging sheath 92. In contrast, Figure 14 And Figure 15 A molded camera tip 46 is shown that is fixed to the distal end of the imaging sheath 92 and is also part of the inner member 40, but the camera tip 46 is not shown in Figure 13 detail.

[0132] The internal component hub 98 extends from the side of the imaging sheath 92. In this example, the imaging sheath 92 passes through the internal component hub 98; however, in other designs, the imaging sheath 92 may terminate at or inside the internal component hub 98. The internal component hub 98 is fixed to the imaging sheath 92 by an overmolding process, but it may also be fixed by adhesive or welding processes, or it may be fitted onto the outside of the imaging sheath 92 by an interference fit.

[0133] In this example, the internal component hub 98 is generally rectangular in shape, with a through hole 102 at its center for accommodating the imaging sheath 92; the through hole 102 is centered on the proximal and distal surfaces of the internal component hub 98, which are parallel to each other. The internal component hub 98 also has a pair of parallel side holes 104, which penetrate the proximal and distal surfaces and are located on either side of the central through hole 102. Figure 12 As shown and will be further explained below, the pair of side holes 104 are used to accommodate a pair of turning lines 106 extending proximally from the intermediate element 42 of the delivery tube 36.

[0134] The opposing sides of the internal element hub 98 (generally perpendicular to the proximal and distal faces) are approximately parallel to each other and parallel to the longitudinal axis of the imaging sheath 92. A wedge-shaped structure 108 extends laterally from one of the sides, gradually narrowing from the distal shoulder towards the proximal end, and eventually intersecting with that side.

[0135] An ear 110 is provided above the proximal end face of the internal element hub 98. The ear extends from the internal element hub 98 and is perpendicular to the longitudinal axis of the imaging sheath 92. The function of the ear 110 is to ensure that the internal element hub 98 maintains the correct orientation when assembled into the hub assembly 68, so that the wedge structure 108 on one side extends from the correct side of the hub assembly 68.

[0136] like Figure 14 and Figure 15 As shown, the imaging sheath 92 contains a flushing channel and an electronic component channel 114, which are parallel to each other and arranged side by side. Specifically, the flushing channel is formed by a flushing tube 112, which is laterally offset within the cavity of the imaging sheath 92; while the electronic component channel 114 is formed in the remaining space beside the flushing tube 112 within the cavity. The flushing tube 112 is in fluid communication with the flushing port 86 on the handle 34, through which flushing fluid can flow from the proximal end to the distal end of the imaging sheath 92.

[0137] It is necessary to maintain a tight sliding contact between the internal element 40 and the intermediate element 42 in order to maintain a tight seal and minimize the possibility of liquid entering the distal end of the delivery tube 36 from between the internal element 40 and the intermediate element 42.

[0138] Figure 13The inner member 40 is shown provided with a receptacle 116 at the distal end of the imaging sheath 92. Figure 14 and Figure 15 The camera tip 46 is shown provided with a proximal, external cannula 118 that is insertable into the receptacle 116. The camera tip 46 is also provided with a distally directed irrigation outlet 120 that is in fluid communication with the irrigation tube 112. To achieve this communication, the camera tip 46 is provided with a proximal, tubular, internal cannula 122 that is insertable into the distal end of the irrigation tube 112. As a result, an irrigation channel extends longitudinally from the irrigation tube 112, through the camera tip 46, from the internal cannula 122, and to the irrigation outlet 120.

[0139] Internally, the camera tip 46 is provided with a dog-leg shaped irrigation channel that laterally offsets the irrigation outlet 120 from the longitudinal axis of the irrigation tube 112. As a result, the irrigation outlet 120 is laterally offset from, and alongside, a distally open recess that houses a PCB 124, light emitting elements 126 (e.g., LEDs), and a CMOS imaging chip 128 that is exposed at the distal end of the camera tip 46. The light emitting elements 126 are positioned alongside the imaging chip 128, preferably one on each side of the CMOS chip 128.

[0140] The camera tip 46 is designed so that the CMOS chip 128 does not extend completely within the camera tip 46, and so that the CMOS chip 128 is not at least partially obscured by the camera tip 46. As a result, the CMOS chip 128 is preferably flush, or at least substantially flush, with the distal end of the camera tip 46.

[0141] A cable 130 that extends along the electronics channel 114 and alongside the irrigation tube 112 is responsible for delivering power and data from the power and data port 88 of the housing 62 to the PCB, LEDs, and imaging chip, and for transmitting image data from the imaging chip back to the power and data port along the inner member 40. In this example, the cable 130 is encased in a protective sheath 132 and is housed in a longitudinal recess in the outer wall of the irrigation tube 112.

[0142] Returning to Figure 12 , the intermediate member 42 is shown provided with the steering sheath 94, an intermediate member hub 100, and a molded steering tip 134. The intermediate member hub 100 is fixed to the proximal end of the steering sheath 94, and the molded steering tip 134 is fixed to the distal end of the steering sheath 94. The steering sheath 94 is shown fitted around and conforming to the imaging sheath 92, leaving the distal end of the imaging sheath 92 with the camera tip 46 projecting distally and exposed.

[0143] The intermediate element hub 100 includes integrally formed tabs 136 that are diametrically opposed about the longitudinal axis of the steering sheath 94 and extend radially therefrom and parallel thereto. As will be explained below, the tabs 136 project into complementary structures in the handle 34 housing 62, thereby limiting axial and circumferential movement of the intermediate element 42 relative to the handle 34. In addition, pairs of integrally formed projections 138 extend laterally from opposite sides of the intermediate element hub 100 and between the opposite tabs 136. In this example, the intermediate element hub 100 is secured to the steering sheath 94 by an overmolding process, but can also (or instead) be secured by adhesive, welding processes, or can be received by the steering sheath 94 by way of an interference fit.

[0144] In combination Figure 16 and Figure 17 As can be seen, the intermediate element 42 also includes a rigid steering pull ring 140 that is circumferentially disposed within the distal end of the steering sheath 94 and is initially axially aligned with the central longitudinal axis 58 of the steering sheath 94. In this example, the steering pull ring 140 is embedded in or wrapped within the wall of the steering sheath 94, sandwiched between the inner and outer layers of the steering sheath 94. The steering tip 134 is secured to the distal end of the steering sheath 94 by an overmolding process or is adhesively secured thereto; the proximal end of the steering tip 134 includes a socket 142 in which the steering pull ring 140 is received and closely fits.

[0145] The steering pull ring 140 and the steering tip 134 are located at the interface of the imaging sheath 92 and the steering sheath 94 and assist in longitudinal movement of the imaging sheath 92 relative to the steering sheath 94. In particular, the imaging sheath 92 can be longitudinally slid within and relative to the steering sheath 94, the steering pull ring 140, and the implant holder formed by the steering tip 134.

[0146] A pair of steering wires 106 that act on opposite sides of the steering pull ring 140 are diametrically opposed about the central longitudinal axis 58 and extend proximally along the steering sheath 94. Like the steering pull ring 140, the steering wires 106 are embedded in the wall of the steering sheath 94, for example, interwoven with or passing through the braided structure of the wall. The steering wires 106 extend proximally from the steering pull ring 140 along the steering sheath 94, pass through the intermediate element hub 100, and extend proximally therefrom where they are crimped to corresponding wires of the steering system 72. As previously described, when the intermediate element hub 100 and the inner element hub 98 are assembled together in the hub assembly 68, the steering wires 106 pass through the parallel side holes 104 of the inner element hub 98.

[0147] During the use of the device 32, the steering system 72 selectively increases the tension of one of the steering lines 106, which pulls the corresponding side of the steering pull ring 140, thereby causing the steering pull ring 140 to deviate from its axial alignment with the central longitudinal axis 58. Since the steering pull ring 140 is embedded in and cooperates with the socket 142 of the steering end 134, the steering end 134 will tilt together with the steering pull ring 140.

[0148] Therefore, the steering sheath 94 bends along its length toward the steering line 106 with greater tension, which also causes the outer sheath 90 and imaging sheath 92 of the delivery tube 36 to bend along their respective lengths. These concentric elements of the delivery tube 36 (outer sheath, steering sheath, imaging sheath) bend together, and the bending location preferentially occurs in the distal longitudinal region of the steering sheath 94, i.e., immediately adjacent to the proximal end of the steering pull ring 140. The inner arc surface of this bend corresponds to the steering line 106 with greater tension, while the outer arc surface corresponds to the steering line 106 with less tension or no tension.

[0149] During use, the steering end 134 serves as a fixator for implants (such as expander 10). For this purpose, the steering end 134 employs a longitudinally stepped profile design, making its distal portion 144 narrower than its proximal portion 146. The radially outer side of the distal portion 144 forms a smaller diameter cylindrical support surface, while the radially outer side of the proximal portion 146 forms a larger diameter cylindrical bearing surface. More specifically, the proximal portion 146 of the steering end 134 is radially oversized relative to the diameter of the steering sheath 94, thus the bearing surface protrudes beyond the surface of the steering sheath 94. The width of the steering sheath 94 preferably does not exceed the proximal portion 146 of the steering end 134, so that the intermediate element 42 can be retractably inserted into the outer element 38 during the assembly of the delivery tube 36. In this example, the proximal portion 146 of the steering end 134 also has a chamfered proximal edge to simplify the assembly process.

[0150] Although the concentric sheaths of the delivery tube 36 can slide relative to each other with minimal frictional resistance, the proximal portion 146 of the steering end 134 can still be designed as an option to assist the outer sheath 90 in sliding relative to the steering sheath 94.

[0151] More specifically, combining Figure 17 It is understood that the distal portion 144 (forming a support surface) of the steering end 134 includes a support tube extending distally beyond the steering sheath 94. This support tube is integrally formed with the proximal portion 146 of the steering end 134, and its outer diameter is smaller than that of the proximal portion 146. A circumferential step 148 causes the outer diameter of the steering end 134 to decrease sharply from the proximal portion 146 to the distal portion 144. This step 148 corresponds to a circumferential shoulder between the proximal portion 146 and the distal portion 144, and the plane containing this shoulder is substantially perpendicular to the longitudinal axis of the steering sheath 94.

[0152] In several embodiments, one or more angularly distributed implant fixation structures, such as implant fixation tabs, are provided, here exemplified by fixation tabs 150, which project radially from the distal portion 144 of the steering tip 134. In various embodiments, one, two, three, four, five or more such implant fixation structures, such as fixation tabs 150, can be provided. The height of the fixation tabs 150, i.e. the amount of radial protrusion, is equal to or slightly less than the height of the step 148 defined by the radial extent of the shoulder relative to the distal portion 144. In contrast, the wire thickness of the dilator 10 is slightly less than the height of the step 148. In the zero deployment stage, the proximal end of the dilator 10 is supported by the distal portion 144 of the steering tip 134, and the distal end is supported by the camera tip 46 of the imaging sheath 92. The fixation tabs 150 limit axial and circumferential movement of the dilator 10 relative to the steering sheath 94.

[0153] In one embodiment, two fixation tabs 150 are provided, both of which are offset to one side of the central longitudinal axis 58 of the steering sheath 94 and circumferentially spaced apart. This pair of tabs 150 forms a smaller sector on one side of the steering tip 134, with an angular spacing of about 120°, and a larger sector on the other side of the steering tip 134, with an angular spacing of about 240°. The third proximal apex of the dilator 10 is accommodated in the larger gap between the two tabs 150.

[0154] The fixation tabs 150 are angularly spaced apart from the shoulder formed by the step 148 of the steering tip 134 in the distal direction, forming a notch or gap 152 between the tabs 150 and the shoulder. When the outer sheath 90 is pressed against the support surface of the distal portion 144, these gaps 152 accommodate the respective proximal apex 16 of the dilator 10 supported by the instrument 32. Thus, the wire thickness of the dilator 10 is slightly less than the length of the gap 152 between the tabs 150 and the step 148. The shoulder formed by the step 148 thus becomes an additional proximal fixation structure, which cooperates with the fixation tabs 150 to clamp the proximal apex 16 of the dilator 10 between the shoulder and the corresponding tab 150, limiting its axial movement relative to the steering tip 134.

[0155] The fixation tabs 150 can also be embedded between the support struts 18 of the dilator 10, which converge at the respective proximal apex 14. Thus, the fixation tabs 150 limit circumferential or angular movement of the dilator 10 relative to the steering tip 134.

[0156] With the aid of the shoulder formed by the fixed lugs 150 and the step 148, the dilator 10 can be constrained from axial and angular movement relative to the handle 34; the only exception is that the distal end of the steering sheath 94 (and thus the steering tip 134 and the dilator 10) can be deflected relative to the handle 34 by operating the steering system 72.

[0157] Viewed from the internal structure (as shown in Figure 16 The steering tip 134 is provided with a circumferential inner shoulder 154 that steps the diameter of the longitudinal inner lumen of the steering tip from the wider proximal portion 146 to the narrower distal portion 144. The inner diameter of the distal portion 144 is a sliding fit for the imaging sheath 92, which can be inside and longitudinally slideable relative to the distal portion 144.

[0158] The proximal portion 146 of the steering tip 134 receives the steering pull ring 140 by interference fit. The steering pull ring 140 can also (or additionally) be secured within the steering tip 134 using a suitable adhesive or welding process for polymers, such as reflow soldering or overmolding. Adhesives can also be used and secured by curing. The distal end of the steering pull ring 140 faces or abuts the proximally facing inner shoulder 154.

[0159] Thus, the steering tip 134 in this example combines the functions of implant fixation and steering, and it not only secures the dilator 10 but also steers the dilator 10 and the sheaths that support the dilator 10. In this regard, it is advantageous to steer behind the dilator 10 (i.e., proximally relative to the dilator 10) so that the dilator 10 is guided forward along the anatomy to the deployed position.

[0160] Thus, viewed proximally from the dilator 10, the steering sheath 94 with the steering pull ring 140 and the steering tip 134 assembled has the following functions: a securing structure that secures and positions the dilator 10; a steering mechanism that acts on the flexible steering segment; and a flexible proximal portion that can travel along the penile lumen. In cooperation with the imaging sheath 92 and the outer sheath 90, the structure of the steering sheath 94 must have sufficient tensile or axial strength to enable the ejection and retraction of the dilator 10 and to ensure that the dilator 10 is smoothly deflected at all stages of deployment. The structure of the steering sheath 94 must also have sufficient torsional strength to enable the angular positioning of the dilator 10 about its central longitudinal axis 58 when the user angularly manipulates the handle 34.

[0161] Returning to Figure 12The outer member 38 includes a tubular outer sheath 90 and an outer member hub 96, wherein the outer member hub 96 is mounted at or near the proximal end of the outer sheath 90. The distal end portion of the outer sheath 90 is coiled rather than braided to enhance fixation to the dilator 10 and accommodate the steering deflection; the proximal end portion is flexible to facilitate navigation of the delivery tube 36, including steering of the delivery tube 36 driven by deflection of the inner steering sheath 94 that is nested within the outer sheath 90. In addition, the proximal end portion of the outer sheath 90 is provided with a series of external markings 156 with graduations and numbers to indicate the depth of insertion of the delivery tube 36 into the urethra of the penis.

[0162] In combination Figure 18 As can be seen, the outer member hub 96 includes a tubular body 158 with a circular cross-section that is concentric with the outer sheath 90. In this example, the outer member hub 96 is fixed to the outer sheath 90 by an overmolding process. In other examples, the outer sheath 90 can be inserted into the outer member hub 96 by an interference fit, and / or can be fixed to the outer member hub 96 by an adhesive or welding process.

[0163] The body 158 of the outer member hub 96 is provided with integral positioning structures, specifically: a proximal flange 160 that circumscribes the body 158 and lies in a plane that is perpendicular to the central longitudinal axis 58 of the outer sheath 90; and an elongated lug 162 that extends radially and lies in a plane that contains the axis 58. These positioning structures 160, 162 are received in complementary structures at the distal end of the hub shell 164 of the hub assembly 68, thereby limiting axial and circumferential movement of the outer member 38 relative to the hub assembly 68. In some examples, the hub shell 164 functions as a hub carriage. In some examples, the hub shell 164 is a hub carriage.

[0164] In combination Figure 19a And 19b The hub shell 164 of the hub assembly 68 is an elongated hollow shell that extends along the central longitudinal axis 58 of the handle 34 housing 62 and is aligned with the corresponding axis of the delivery tube 36. The hub shell 164 includes a generally cuboid body 166 and an integral open tubular extension 168 that extends distally from the body 166; the tubular extension 168 is centered on the central longitudinal axis 58 and is in communication with the interior of the body 166.

[0165] The hub shell 164 is divided into two shell components along a central longitudinal plane that bisects the tubular extension 168 and a pair of opposite sides of the cuboid body 166. The two shell components are brought together and secured about their planar interface. In this example, the shell components are secured by screws 170 that are located on either side of the central longitudinal axis 58 and are mounted at the junction of the body 166 and the tubular extension 168 of the hub shell 164.

[0166] After assembly, the hub shell 164 receives, encloses and secures the respective hubs 96, 98, 100 of the outer element 38, the intermediate element 42 and the inner element 40 of the delivery tube 36. The outer element hub 96, the intermediate element hub 100 and the inner element hub 98 are thus arranged in succession in the hub shell 164 in the proximal direction. The hub shell 164 supports the outer element hub 96 at the distal end, the inner element hub 98 at the proximal end and has a longitudinally extending intermediate portion connecting the distal and proximal ends and surrounding the intermediate element hub 100 for support.

[0167] The tubular extension 168 of the hub shell 164 forms an inner passage of circular cross-section which closely fits the body 158 of the outer element hub 96. Screws 170 for securing the two shell parts clamp the outer element hub 96 between the distal ends of the shell parts which together form the tubular extension 168.

[0168] The tubular extension 168 of the hub shell 164 further has an inner positioning structure which mates with an outer positioning structure of the outer element hub 96. Specifically, the flange 160 of the outer element hub 96 is inserted into a circumferential groove in the tubular extension 168 to prevent axial movement of the outer element 38 relative to the hub shell 164. Thus, the outer element 38 of the delivery tube 36 always moves with the hub shell 164 in the longitudinal direction of the housing 62 of the handle 34. Similarly, the lugs 162 of the outer element hub 96 are inserted into longitudinal grooves in the tubular extension to lock the outer element 38 against angular movement relative to the hub shell 164 about the central longitudinal axis 58.

[0169] In combination Figure 20 As mentioned above, the outer element 38 and the inner element 40 of the delivery tube 36 are axially movable relative to the intermediate element 42 and the handle 34. To this end, the hub shell 164 is reciprocally movable within the housing 62 of the handle along the central longitudinal axis 58 over a certain stroke. The hub shell 164 is supported between two longitudinally extending parallel guide rail structures 172 which are formed integrally with the inner surface of each half shell 64 of the housing 62 and along which the hub shell 164 is slidable. The hub shell 164 thus acts as a carriage for the outer element hub 96 and the inner element hub 98, moving these two hubs 96, 98 along a retraction path which is longitudinally extending within the housing 62 and which is parallel to the central longitudinal axis 58.

[0170] In contrast, as previously described, the intermediate element 42 of the delivery tube 36 is fixed relative to the handle 34 and cannot move axially. Therefore, the hub shell 164 must be able to move longitudinally about the intermediate element hub 100 housed within its body 166, and the two are movable relative to one another. To accomplish this, the opposing edges of the two shell components at their planar interface are cut away so that, when the shell components are assembled, a pair of opposing longitudinal slots 174 are formed. Each slot 174 has a closed distal end and an open proximal end.

[0171] In combination Figure 20 It will be appreciated that the longitudinal slots 174 extend through the aforementioned pair of sides of the body of the hub shell 164 for receiving the two diametrically opposed tabs 136 that extend laterally from the intermediate element hub 100. These tabs 136 extend through the longitudinal slots 174 from the hub shell 164 and are received within corresponding slot structures 176 integrally formed on the inner surface of each half shell 64 of the housing 62. In this manner, the intermediate element hub 100 is locked against axial or angular movement relative to the housing 62, while the longitudinal slots 174 provide clearance around the tabs 136 to allow the hub shell 164, and the outer and inner element hubs 96, 98, to move longitudinally relative to the intermediate element hub 100. The hub shell 164 will slide over the aforementioned projections 138 of the intermediate element hub 100 between the opposing tabs 136, which maintain the lateral alignment of the hub shell 164 with the intermediate element hub 100.

[0172] Returning to Figure 19a , the cuboid body 166 of the hub shell 164 also has an additional side 178 between the pair of sides with longitudinal slots. This additional side 178 has C-shaped slits formed therein that create resiliently deflectable tabs 180 and 182 that are integral with the body. One tab 180 is located at the distal end of the side 178, and the other tab 182 is located at the proximal end of the side 178.

[0173] The distal tab 180 has an integral flange 184 at its free end facing distally that projects outwardly from the side 178 of the body 166. As shown in Figure 21a , the flange 184 snaps into a complementary inwardly facing groove 186 in the adjacent rail structure of the housing 62 that is used to guide the longitudinal movement of the hub shell 164 relative to the handle 34. The snap of the flange into the groove locks the hub shell 164 against the aforementioned longitudinal movement. This is to prevent the inadvertent retraction of the outer element 38 of the delivery tube 36 and thus the inadvertent switching of the instrument 32 from the zero deployment stage to the first deployment stage. This locking is only released when the user intentionally triggers this switching by applying sufficient force to the deployment trigger 48. In this case (when sufficient force is applied), as shown in Figure 21bAs shown, the distal tongue 180 will deflect inward, causing the flange 184 to disengage from the groove 186, thereby releasing the hub 164 and enabling it to move relative to the housing 62.

[0174] Back Figure 19a The proximal tongue 182 is flush with the side surface 178 surrounding the body 166, but at its free end facing proximal end, the transverse slit 188 is widened to accommodate and engage the aforementioned wedge-shaped structure 108 on the side surface of the internal element hub 98. In the initial state, this engagement secures the internal element hub 98 to the proximal position of the hub housing 164. Therefore, the engagement... Figures 21a to 21c It can be seen that when the device 32 switches from the zero deployment stage to the first deployment stage, the internal component hub 98 will be constrained and move together with the hub housing 164 and the external component hub 96. Similarly, if the device 32 reverts from the first deployment stage to the zero deployment stage, the internal component hub 98 will also be constrained and move together with the hub housing 164 and the external component hub 96.

[0175] Unlike the external component hub 96, the internal component hub 98 is not fixed to the surrounding hub housing 164, but can move relative to the hub housing 164 within a limited longitudinal range. Figure 21d It is understood that this design allows the movement of the external component hub 96 (which in turn drives the outer sheath 90) to be independent of and no longer synchronized with the movement of the internal component hub 98 (which in turn drives the imaging sheath 92) when the device 32 switches from the first deployment stage to the second deployment stage.

[0176] Therefore, as Figures 21a to 21c As shown, during the transition from the zero deployment phase to the first deployment phase, the internal component hub 98 moves proximally along with the hub housing 164. Subsequently, as... Figure 21d As shown, the continuous proximal movement of the inner component hub 98 ceases, but from the first deployment phase to the second deployment phase, the hub housing 164 moves independently of the inner component hub 98 and continues to move proximal relative to it. The proximal tongue 182 deflects outward to avoid the wedge structure 108, thereby releasing the inner component hub 98 and enabling the hub housing 164 to perform the aforementioned relative movement. As the hub housing 164 moves proximal relative to the inner component hub 98, the proximal tongue 182 elastically returns to its original position and slides smoothly along the inclined surface of the wedge structure 108.

[0177] The decoupling of the internal component hub 98 from the hub housing 164 is achieved through a blocking element; this blocking element prevents the internal component hub 98 from moving proximally, but allows the hub housing 164 to continue moving proximally relative to the housing 62. Specifically, as Figure 21c and 21dAs shown, proximal movement of the inner element hub 98 is blocked by an integral stop feature 190 on the housing 62. The stop feature 190 is aligned with the proximally open longitudinal slot 174 of the hub shell 164 so as to be able to snap into the longitudinal slot 174 as the hub shell 164 continues to move proximally.

[0178] In combination Figures 22a to 22d , the deployment system 70 drives the longitudinal movement of the hub shell 164 by means of an integral rack extension 192 (e.g., an arm-like structure) that extends proximally from the main body 166. As shown in Figure 19a and 19b , the rack extension 192 is conveniently integral with one of the housing components. The rack extension 192 is offset laterally from the central longitudinal axis 58 of the housing 62, but extends generally parallel thereto. An integral rack structure 194 comprising a series of transverse teeth extends along one lateral surface of the rack extension 192 toward the central longitudinal axis 58.

[0179] Figures 22a to 22d As shown, according to one embodiment, the deployment system 70 comprises a transmission gear train 196 that receives a driving force input from the linear movement of the deployment trigger 48 along the trigger axis 78 and transmits a corresponding driving force output to the rack extension 192 of the hub shell 164. In one embodiment, the gear train is a gear set. The rack extension 192 translates the rotational motion of the gear train 196 into linear motion of the hub shell 164 that accurately follows the linear motion of the deployment trigger 48, but in a longitudinal direction that is perpendicular to the trigger axis 78.

[0180] The gear train 196 includes an input gear 198 that meshes with a rack 200 extending from the deployment trigger 48 and parallel to the trigger axis 78. The input gear 198 meshes with an output gear 202 that, in turn, meshes with the rack extension 192 of the hub shell 164. The reversal of the direction of transmission achieved by the gear train 196 ensures that pressing the deployment trigger 48 along the trigger axis 78 causes the hub shell 164 to move proximally within the handle 34 when the instrument 32 is switched from the zero deployment stage to the first and second deployment stages.

[0181] If the user decides to retract the instrument 32 from the first deployment stage to the zero deployment stage, the user simply pulls or withdraws the deployment trigger 48 from the housing 62 of the handle 34 to cause the hub shell 164 to move distally within the handle 34. To this end, the outer portion of the deployment trigger 48 is provided with concave recesses 204 on opposite sides to facilitate the user's thumb and index finger to pinch the trigger for operation.

[0182] The overall gear ratio of gear train 196 is primarily selected based on mechanical advantages, allowing the user operating deployment trigger 48 to easily push hub 164, which in turn drives the external components 38 and internal components 40 of delivery tube 36. Simultaneously, the gear ratio selection also considers sensitivity requirements: a small movement of deployment trigger 48 along trigger axis 78 can correspondingly drive a larger movement of hub 164. The purpose of this design is to ensure that instrument 32 can quickly and clearly switch from one deployment stage to another, avoiding prolonged stagnation of hub 164 in the intermediate position during stage transitions. Although instrument 32 is specifically designed for high sensitivity to the movement of deployment trigger 48, the positioning mechanism prevents accidental operation.

[0183] like Figures 23a to 23d As shown, inside the housing 62, the deployment trigger 48, used as a deployment control element, includes an integral trigger ramp 204 facing the positioning axis 80. The trigger ramp 204 gradually moves away from the positioning axis 80 (in a sloping, converging manner) along a direction extending into the housing 62 and parallel to the trigger axis 78. At the inner end of the trigger ramp 204, there is a base platform 206 facing the positioning axis 80; while at the outer end of the trigger ramp 204, there is an inwardly projecting shoulder 208 extending towards the positioning axis 80.

[0184] The positioning button 60, which serves as a positioning release element, has an integrated follower engagement structure, namely a protrusion 210, on its inner side. This protrusion gradually tapers (becomes tapered) along a direction extending into the housing 62 and parallel to the positioning axis 80. The tapered structure of the protrusion 210 forms a positioning ramp 212, which faces away from the trigger axis 78.

[0185] A follower 214 is provided within the housing 62. This follower interacts with the deployment trigger 48 and the positioning button 60, being both driven by and exerting force on them. The follower 214 is pushed towards the trigger axis 78 by an integral spring 216; the spring acts in a compressed state between the adjacent outer wall of the housing 62 and the follower 214. The spring 216 sequentially presses the follower 214 against the trigger ramp 204 and the positioning ramp 212; according to one embodiment, when the deployment trigger 48 and the positioning button 60 are pressed inward in sequence, these ramps 204 and 212 act on the follower 214 sequentially through a cam action.

[0186] The follower 214 is provided with a trigger bearing edge 218 for abutting the trigger ramp 204 and a positioning bearing edge 220 for abutting the positioning ramp 212. In particular, the trigger bearing edge 218 is located at the free end of the follower 214 closest to the trigger axis 78; the positioning bearing edge 220 is located closer to the spring 216, in the present example, the edge is constituted by the inner edge of a window 222 through the follower 214. In more detail, the positioning bearing edge 220 is located on a lateral stop 224 of the follower; in the present example, the lateral stop is constituted by the inner side of the frame around the window 222, adjacent to the spring 216 of the follower 214. The width of the window 222 is sufficient to accommodate the protrusion 210 on the inside of the positioning button 60.

[0187] By interaction of the trigger ramp 204 with the trigger bearing edge 218 and of the positioning ramp 212 with the positioning bearing edge 220, the follower 214 can assume any one of three states depending on the position of the deployment trigger 48 and of the positioning button 60. In particular, the states of the follower 214 are as follows: as shown in Figure 23a , when the deployment trigger 48 is in the extended position corresponding to the zero deployment stage, the follower is in the positioning stop position; as shown in Figure 23b , when the deployment trigger 48 is pressed to the intermediate position corresponding to the first deployment stage, the follower is in the deployment stop or trigger stop position; as shown in Figure 23c , when the positioning button 60 is pressed while in the first deployment stage, the follower is in the deployment release or trigger release position. This enables the deployment trigger 48 to be moved further inwards to the fully retracted position corresponding to the second deployment stage, as shown in Figure 23d . Movement of the follower 214 from the positioning stop position to the intermediate trigger stop position and from the latter to the trigger release position requires overcoming the biasing force of the spring 216.

[0188] Therefore, pressing the deployment trigger 48 inwards to bring the instrument 32 into the first deployment stage moves the follower 214 to the trigger stop position shown in Figure 23a ; in this position, the deployment trigger 48 cannot be moved further inwards, but the positioning button 60 can be pressed inwards. The trigger stop position can thus also be considered a positioning release position. Subsequently, pressing the positioning button 60 inwards moves the follower 214 to the trigger release position; in this position, the deployment trigger 48 can be moved further inwards, thus transitioning the instrument 32 from the first deployment stage to the second deployment stage.

[0189] In particular, as shown in Figure 23aAs shown, when the deployment trigger 48 is in the extended position corresponding to the zero deployment stage, the trigger bearing edge 218 of the follower 214 abuts against the base platform 206 at the inner end of the trigger ramp 204. At this time, the blocking member 224 of the follower 214 aligns with the protrusion 210 of the positioning button 60, thereby preventing the positioning button 60 from moving inward.

[0190] like Figure 23b As shown, when the deployment trigger 48 is pressed inward and moves toward the retracted position corresponding to the first deployment stage, the trigger ramp 204 slides over the trigger bearing edge 218 of the follower 214, overcoming the biasing force of the spring 216 and pushing the follower 214 away from the trigger axis 78. The deployment trigger 48 continues to move inward until the follower 214 touches the shoulder 208 at the outer end of the trigger ramp 204, at which point the deployment trigger 48 is in the position corresponding to the first deployment stage. The interaction between the follower 214 and the shoulder 208 initially prevents the deployment trigger 48 from moving further inward and beyond the position of the first deployment stage.

[0191] Under the action of the trigger ramp 204, the follower 214 moves away from the trigger axis 78, which causes the stop 224 of the follower 214 to be misaligned with the protrusion 210 of the positioning button 60; conversely, the window 222 of the follower 214 will be aligned with the protrusion 210 of the positioning button 60. When the protrusion 210 is accommodated in the window 222, the positioning button 60 can move inward.

[0192] When the protrusion 210 of the positioning button 60 enters the window 222 of the follower 214, the positioning ramp 212 contacts the positioning bearing edge 220 on the transverse stop 224, which forms the inner edge of the window 222. As the positioning button 60 continues to move inward, the positioning ramp 212 slides past the positioning bearing edge 220, thereby overcoming the biasing force of the spring 216 and pushing the follower 214 further away from the trigger axis 78. This further movement of the follower 214 disengages it from the shoulder 208 at the outer end of the trigger ramp 204, allowing the deployment trigger 48 to move further inward, bypassing the first deployment stage and entering the second deployment stage.

[0193] If the deployment trigger 48 is moved in the reverse direction, the device 32 will be moved back from the first deployment stage to the zero deployment stage. The follower 214 will return to its initial position, at which point its trigger bearing edge 218 will abut against the base platform 206 at the inner end of the trigger ramp 204. At this time, the blocking member 224 of the follower 214 will align with the protrusion 210 of the positioning button 60 again, thereby preventing the positioning button 60 from moving inward.

[0194] Accordingly, the positioning button 60 is configured to allow the deployment trigger 48 to move to the second deployment stage, provided that the deployment trigger 48 is first moved from the zero deployment stage to the first deployment stage, thereby unlocking the positioning button for actuation. When the deployment trigger 48 is pressed inwardly to bring the instrument 32 into the first deployment stage, the follower 214 is urged to move against the biasing force of the spring 216. This movement of the follower enables the positioning button 60 to be pressed inwardly. Subsequently, pressing the positioning button 60 inwardly enables the deployment trigger 48 to be moved further inwardly, thereby switching the instrument 32 from the first deployment stage to the second deployment stage.

[0195] Finally, in combination Figure 24a and 24b The steering lever 44 of the steering system 72 acts on a steering dial 226, which is rotatable within the housing 62 about a pivot axis 82. Steering wires (not shown) extend distally from opposite sides of the steering dial 226 and are crimped to corresponding steering wires 106 extending proximally from the intermediate element hub 100. Thus, when the steering lever 44 is rotated to cause the steering dial 226 to rotate, selective tension is applied to the steering wires 106, which causes the deflection of the steering sheath 94 of the delivery tube 36 as described above.

[0196] At the inner end of the housing 62, the steering lever 44 is provided with an integral fork 228 that is distributed about the pivot axis 82 of the steering lever 44. The lock axis 84 (i.e. the longitudinal axis of the steering lever 44) mentioned above extends in a radial direction and intersects the pivot axis 82.

[0197] The fork 228 encircles and engages a complementary hub boss 230 of the steering dial 226. In the direction of the lock axis 84, the fork 228 is dimensionally oversized with respect to the hub boss 230; in the direction perpendicular to the axis 84, the hub boss 230 and the fork 228 form a close sliding fit. Specifically, parallel side planes of the hub boss 230 abut opposite side arms of the fork 228, thereby locking the fork 228 against angular movement with respect to the hub boss 230. Thus, when the steering lever 44 is angularly moved (e.g. by a user operating the steering lever with a thumb), the torque transmitted thereby causes the dial 226 to rotate about the pivot axis 82. Conversely, the fork 228 is able to move reciprocally in the direction parallel to the lock axis 84. In this case, the side planes of the hub boss 230 slide within the opposite side arms of the fork 228.

[0198] The spring 232 is distributed around the locking axis 84 outside the pivot axis 82 to act between the fork 228 and the hub boss 230 in a compressed state to push the steering rod 44 outward along the locking axis 84 (to provide an outward biasing force). Thus, a user can use a thumb to overcome the biasing force of the spring 232 to press the steering rod 44 inward to translate into the housing 62 to release the locking state of the steering rod 44 to enable angular movement. When the thumb releases the inward pressure, the biasing force of the spring 232 pushes the steering rod 44 back to the outward position; in this position, the steering rod 44 is re-locked to prevent accidental angular movement.

[0199] To achieve the locking function of the steering rod 44, the fork 228 is provided with a locking structure outwardly facing along the locking axis 84. In this example, the locking structure is specifically a set of convex arc-shaped teeth 234; and it is matched with a set of complementary concave arc-shaped teeth 236 inwardly facing from the inner surface of the housing 62, both corresponding to each other.

[0200] Both sets of teeth 234, 236 are curved along their lengths with a constant radius of curvature, and the center of the curvature coincides with the pivot axis 82. The teeth on the teeth 234, 236 are spaced along the length of the teeth, so they are angularly spaced around the pivot axis 82. In this example, the direction of the teeth is perpendicular to the length direction of the respective teeth 234, 236. Cleverly, as shown, the concave arc-shaped teeth 236 inwardly facing from the housing 62 are integrally molded with one or two half-housings 64 of the housing 62; these half-housings 64 also have a corresponding curvature around the pivot axis 82.

[0201] When the steering rod 44 is released, the biasing force of the spring 232 pushes the fork 228 and its locking structure outward to engage the teeth of the inwardly facing teeth 236 corresponding to the current angular position of the steering rod 44. This action locks the steering rod 44 at the desired angular position. Conversely, when the steering rod 44 is pressed against the biasing force of the spring 232, the locking structure disengages from the teeth of the inwardly facing teeth 236, thereby releasing the locking of the steering rod 44 to enable angular movement.

[0202] Within the scope of the inventive concept, various variant designs can also be derived. For example: the instrument can be integrated with a built-in power source; the imaging function can be realized through a non-chip-based non-digital imaging system, such as through a fiber bundle to transmit images; the stiffness of the imaging sheath can be customized along its length, for example, through a customized braided structure (including braided or coiled elements with different densities, pitches, angles, and / or thicknesses) combined with polymer hardness, to provide stable support for the implant and flexible navigation in the deflected steering sheath.

[0203] In the illustrated example, the implant fixation structure is a molded turn tip component that houses the turn ring as a separate component. In another embodiment, however, the implant fixation structure can be integrated with the pull ring or other turn structure as a single component.

[0204] The ramp structure that deploys the trigger and the positioning button can alternatively or additionally be provided on the follower.

[0205] Changes and modifications can be made to the disclosed embodiments without departing from the scope of the disclosure. Each of the disclosed aspects and examples can stand on its own, or can be combined in various permutations and combinations with one another. Those of skill in the art will understand that information and examples, shown and described in relation to one aspect, can be re-used in relation to another aspect.

[0206] While various modifications and alterations of the methods, devices, and systems described herein have been discussed, other changes can be made to the disclosed embodiments without departing from the spirit and scope of the disclosure. For example, each of the disclosed aspects and examples can stand on its own, or can be combined in various permutations and combinations with one another. Those of skill in the art will understand that information and examples, shown and described in relation to one aspect, can be re-used in relation to another aspect. In addition, certain features, aspects, methods, properties, characteristics, qualities, elements, etc. disclosed in relation to any one example can be applied to all other examples listed herein. Unless otherwise expressly specified, the various steps of the methods described herein are not limited to any particular order of execution. Any of the methods disclosed herein need not be performed in the order described. Unless specifically stated or otherwise understood in context, the use of ordinal terms, such as "then," "next," "after," "subsequently," and other comparable terms, is generally intended to convey a chronological sequence of execution, but is not intended to limit the order of execution unless explicitly stated otherwise. Thus, some examples can perform the sequences of operations described herein, while other examples can follow different sequences of operations.

[0207] Conditional language used herein, including the terms "could," "might," "may," "for example," and the like, unless specifically stated otherwise, generally are intended to convey that certain examples include, while other examples do not include, certain features, elements, and / or states. Thus, such conditional language is not generally intended to imply that features, elements, and / or states are in any way required, or that one or more examples are necessarily comprised of any particular features, elements, and / or states. Unless specifically stated otherwise, the use of ordinal terms, such as "first," "second," "third," and the like, is generally intended to convey a chronological order, but is not intended to imply any order of execution unless explicitly stated otherwise. Thus, a feature, element, or step that is described as "first" can be executed before, after, or at the same time as a feature, element, or step that is described as "second," unless specifically stated otherwise.

[0208] The methods disclosed herein can include specific operations performed by an operator; however, the methods equally encompass any instructions for the operations made by a user or third party in an explicit or implicit manner. For example, the operation "positioning the instrument" includes "instructing positioning of the instrument."

[0209] The ranges disclosed herein also encompass any and all overlap ranges, sub-ranges, and combinations thereof. Language such as "up to," "at least," "greater than," "less than," "between," and the like includes the number value itself. Numerical values prefaced by "about" or "approximately" include the recited value, and should be interpreted in the context according to the specific circumstances (e.g., as precisely as reasonably possible, such as ±5%, ±10%, ±15%, etc., as reasonable). For example, "about 4 mm" includes "4 mm." Phrases prefaced by "substantially" or the like include the recited state, and should be interpreted according to the context (e.g., as close as reasonably possible to the recited state, under the circumstances). For example, "substantially linear" includes "linear." Unless otherwise stated, all measurements are made at standard temperature and pressure. The recitation of "at least one" is intended to require selection of at least one item from the list of items following the term, and not to require selection of one of each type of item from the list of items. For example, "at least one of A, B, and C" can include: A; B; C; A and B; A and C; B and C; or A, B, and C.

Claims

1. A deployment system for deploying an implant within a patient's body, the system comprising: a deployment driver operable in response to movement of a deployment control element; the deployment control element being movable through a range of positions from a first position in which the implant is undeployed, to a second position in which the implant is partially deployed, to a third position in which the implant is fully deployed; and a positioning mechanism configured to prevent movement of the deployment control element from the second position to the third position; wherein the positioning mechanism comprises: a follower which is movable by the deployment control element from the first position to the second position to a deployment stop position, thereby preventing further movement of the deployment control element to the third position; and a positioning release element which is movable to an unlocked position, movement of the positioning release element acting on the follower to move the follower from the deployment stop position to a deployment release position in which the deployment control element is free to move from the second position to the third position. the follower is movable from a positioning stop position to the deployment stop position, the follower preventing movement of the positioning release element to the unlocked position in the positioning stop position.

2. The system of claim 1, wherein: the positioning release element is unable to move from the locked position to the unlocked position until the follower has moved to the deployment stop position to unlock the operating authority.

3. The system of claim 2, wherein: the follower is in the positioning stop position when the deployment control element is in the first position.

4. The system of claim 2 or 3, wherein: the follower is biased towards the positioning stop position.

5. The system of any one of claims 2 to 4, wherein: the follower is movable against the bias to the deployment stop position and the deployment release position.

6. The system of any preceding claim, wherein: the positioning release element is located adjacent the deployment control element.

7. The system of any preceding claim, wherein: the deployment control element is movable along a trigger axis between the first, second and third positions, the follower is movable along a follower axis which is perpendicular to the trigger axis between the positioning stop position and the positioning release position, and the positioning release element is movable along a positioning axis between the locked position and the unlocked position.

8. The system of any preceding claim, wherein: the positioning axis is substantially parallel to the trigger axis.

9. The system of claim 8, wherein: a trigger ramp which is movable with the deployment control element is located opposite the follower and is inclined relative to the trigger axis, such that when the deployment control element is moved along the trigger axis towards the second position, the ramp slides relative to the follower to drive the follower along the follower axis to the positioning release position.

10. The system of claim 8 or 9, wherein: the trigger ramp is shaped such that when the deployment control element reaches the second position, the ramp engages the follower to prevent further movement of the deployment control element towards the third position.

11. The system of claim 10, wherein: the trigger ramp includes a shoulder which extends transversely relative to the inclined surface of the trigger ramp and is located opposite the follower.

12. The system of claim 11, wherein: the follower includes a block and an opening, the block being in blocking opposition with a feature of the positioning release element when the follower is in the positioning stop position, and the opening being in receiving opposition with the feature when the follower is in the positioning release position.

13. The system of any preceding claim, wherein: the block and the opening are located in sequence along the follower axis. ​ 14. The system of claim 13, wherein: ​ 15. The system of claim 13 or 14, wherein: The structure of the positioning release element includes a positioning ramp, which is arranged opposite to the follower and is inclined relative to the positioning axis. In this way, when the positioning release element moves along the positioning axis to the unlocking position, the positioning ramp slides relative to the follower, thereby driving the follower to move along the follower axis, i.e. to pass through the enabling position and reach the release position, which can release the restriction on the deployment control element, so that the deployment control element can move from the second position to the third position.

16. The system of claim 15, wherein: The movement of the follower to the release position causes the follower to disengage from the trigger ramp.

17. The system of claim 16 dependent on claim 12, characterized in that: The movement of the follower to the release position causes the follower to be lifted and completely disengage from the shoulder.

18. The system of any preceding claim, wherein: The deployment control element includes a holding structure, which is used to facilitate the operator to hold the deployment control element and pull it back from the second position to the first position.

19. A method of operating an implant deployment instrument, comprising the steps of: moving a deployment control element of the instrument from a first position in which the implant is not deployed to a second position in which the implant is partially deployed; moving a follower of the instrument by the movement of the deployment control element to a deployment stop position in which the follower prevents the deployment control element from moving further to a third position in which the implant is fully deployed; moving a positioning release element of the instrument to an unlocking position; the movement of the positioning release element acts on the follower to move the follower to a deployment release position; in the deployment release position, the deployment control element is free to move from the second position to the third position.

20. The method of claim 19, wherein: The method includes moving the follower from a positioning stop position to a deployment stop position; in the positioning stop position, the follower prevents the positioning release element from moving to the unlocking position.

21. The method of claim 19 or 20, wherein: The deployment control element and the positioning release element apply force to the follower through respective cam actions.

22. The method of any one of claims 19 to 21, wherein: The method includes moving the deployment control element and the positioning release element along substantially parallel axes.

23. The method of any one of claims 19 to 22, wherein: The method includes moving the follower in a direction perpendicular to the movement direction of the deployment control element and the positioning release element.

24. The method of any one of claims 19 to 23, wherein: The method includes applying a biasing force to the follower to abut against the deployment control element and the positioning release element.

25. The method of any one of claims 19 to 24, wherein: The method includes moving the follower to the deployment stop position and the deployment release position against the biasing force. The method includes applying a biasing force to the follower to abut against the deployment control element and the positioning release element. The method includes moving the follower to the deployment stop position and the deployment release position against the biasing force.

Images