Patent Description:
Various surgical procedures involve the use of medical devices that require an energy source, e.g., to provide a discharge force to components of the devices. For example, an intraocular lens inserter device may be used to deliver a replacement lens within an eye suffering from a cataract. Such an IOL inserter may require an external power source to push a lens loaded into the inserter into a patient's eye.

Accordingly, energy sources for IOL inserters and other medical devices or tools would be useful.

<CIT> describes a pressure bulb cap welded to the neck of a pressure bulb. The cap includes a relatively thin wall adapted to be pierced by a piercing pin when the bulb is introduced into syphon.

<CIT> discloses a pressure relief device for a container having a cylindrical side wall which is closed at one end by an internally concave bottom wall. The device comprises an externally protruding first cup formed as an impression in the container bottom wall. The first cup has a first circular wall which is joined at one end to the container bottom wall and which is closed at the opposite end by a first base portion; A tab member is located in the first base portion. The tab member is partially circumscribed by a line of reduced material thickness along which the first base portion is adapted to separate in response to an overpressurization of the container contents, thus freeing the tab member for outward deflection to provide an outlet through which the contents may escape. A second element having a second circular wall is forcibly received within the first circular wall of the first cup. The second circular wall is dimensioned to coact with the first circular wall to radially stress the first base portion in tension.

<CIT> discloses a pressure vessel that includes a tank containing fluid under pressure, and includes a closure cap for closing the tank. The closure cap is a unitary part made entirely of a homogeneous material. The unitary part includes a rupturable closure wall which, when ruptured, permits fluid to flow outward from the tank. The unitary part also includes a conduit for directing fluid to flow outward from an outlet opening when the closure wall is ruptured. The closure wall has oppositely facing inner and outer side surfaces and includes a stress riser. The side surfaces have contours which direct the fluid pressure to maintain the stress riser under compressive stress and shear stress, rather than tensile stress, so as to resist creep throughout the time that the fluid is contained under pressure in the tank.

The present disclosure is directed to single-use gas canisters that may be loaded into a medical device or other tool for providing energy during use of the medical device or other tool, and to methods for making such canisters.

According to the claimed invention there is provided a single-use canister and method of making a single-use canister as claimed in the appended claims.

In accordance with an exemplary embodiment, a single-use canister is provided that includes an elongate, e.g., cylindrical, body and a cap attached to the body to define a cavity filled with gas, e.g., pressurized and/or at least partially liquefied carbon dioxide. The body includes a barrel region defining a first diameter, an enclosed first end, and a neck region, optionally defining a second diameter smaller than the first diameter, and extending from the barrel region to an open second end defining an end wall,
the body defining a central axis extending between the first end and the second end. The cap includes an annular portion including a closed first end an open second end, a penetrable or separable septum formed in the first end, and an annular flange extending radially from the second end of the annular portion, thereby defining a lower surface defining a plane substantially perpendicular to the central axis, and an annular projection extending from the lower surface.

The first end of the annular portion is inserted into the open second end of the body of the canister such that the annular portion is spaced from an interior surface of the neck region and the septum is disposed within the neck region, and the projection may be welded to the end wall of the second end of the body, thereby enclosing the cavity.

A gas-actuated tool is described that includes a housing comprising a functional portion and an actuator portion including a chamber; a canister within the chamber comprising an elongate body comprising an enclosed first end and an open second end, a cap welded to the open second end of the elongate body and including a septum, thereby defining an interior cavity filled with pressurized gas, the septum comprising a central region and a relatively-thin perimeter at least partially surrounding the central region; and a carriage movable within the housing from the first position, the carriage comprising a pin disposed adjacent the septum, the pin including a blunt, beveled tip. An actuator on the actuator portion is coupled to the carriage such that initial activation of the actuator causes the carriage to move from the first position to a second position such that the beveled tip of the pin applies localized force to the septum to at least partially separate the septum from the cap, thereby releasing pressurized gas from the canister into one or more passages within the housing.

In accordance with another embodiment, a method is provided for making a single-use canister that includes providing an elongate, e.g., cylindrical, body comprising a barrel region defining a first diameter, an enclosed first end, and a neck region defining a second diameter smaller than the first diameter and extending from the barrel region to an open second end defining an annular end wall, the body defining a central axis extending between the first end and the second end; and providing a cap comprising an annular portion including a closed first end and an open second end, a penetrable or separable septum formed in the first end, and an annular flange extending radially from the second end of the annular portion, thereby defining a lower surface defining a plane substantially perpendicular to the central axis, and an annular projection extending from the lower surface. The first end of the annular portion is inserted into the open second end of the body of the canister such that the annular portion is spaced from an interior surface of the neck region and the septum is disposed within the neck region. Gas, e.g. , carbon dioxide, nitrogen, or hydrofluorocarbon, is introduced into an interior of the body, and the projection is welded to the end wall of the second end of the body, thereby enclosing a cavity of the canister with the gas therein.

Alternatively, in an unclaimed example, the cap (including a separable septum) may include an outer flange that is larger than the open second end of the body. Instead of inserting the cap into the open second end, the flange may be positioned over the open second end and welded to the neck region.

In accordance with yet another example, a method is provided for preparing a medical device or other tool for a procedure that includes providing a device comprising a housing including a chamber with a canister therein, an actuator, and a carriage in a first position within the housing, the canister comprising an elongate body comprising an enclosed first end and an open second end, a cap welded to the open second end including a septum, thereby defining an interior cavity filled with pressurized and/or at least partially liquefied gas; and actuating the actuator to cause the carriage to move from the first position to a second position such that a pin on the carriage opens the septum, thereby releasing pressurized gas from the canister into one or more passages within the device. In one embodiment, the septum may be a relatively thin-walled panel that may be penetrated or punctured by the pin to open the cap. According to the claimed invention, the septum includes a relatively thin perimeter surrounding a relatively thick central portion such that, the pin causes at least a portion of the perimeter to tear inwardly to open the cap.

In accordance with still another example, a method is provided for preparing a medical device or other tool for a procedure that includes providing a canister comprising an elongate body comprising an enclosed first end and an open second end, a cap welded to the open second end including a septum, thereby defining an interior cavity filled with pressurized and/or at least partially liquefied gas; loading the canister into a housing of a device; and actuating the device to cause a pin in the housing to open the septum, thereby releasing pressurized gas from the canister into one or more passages within the device.

In accordance with another example, a method is provided for performing a procedure that includes providing a medical device comprising a housing including a chamber with a canister therein, an actuator, and a carriage in a first position within the housing, the canister comprising an elongate body comprising an enclosed first end and an open second end, a cap welded to the open second end including a septum, thereby defining an interior cavity filled with pressurized and/or at least partially liquefied gas; initially actuating the actuator to cause the carriage to move from the first position to a second position such that a pin on the carriage opens the septum, thereby releasing pressurized gas from the canister into one or more passages within the medical device to pressurize an incompressible liquid within the housing; and subsequently actuating the actuator, thereby causing the incompressible liquid to flow and deliver one of an agent and an implant from the medical device into a patient.

In accordance with still another example, a medical device is provided that includes a housing comprising a treatment portion and an actuator portion including a chamber; a canister within the chamber comprising an elongate body comprising an enclosed first end and an open second end, a cap welded to the open second end and including a penetrable or separable septum, thereby defining an interior cavity filled with pressurized gas; a carriage movable within the housing from the first position, the carriage comprising a pin disposed adjacent the septum; and an actuator on the actuator portion coupled to the carriage such that initial activation of the actuator causes the carriage to move from the first position to a second position such that the pin opens the septum, thereby releasing pressurized gas from the canister into one or more passages within the medical device.

In accordance with yet another example, a gas-powered tool is provided that includes a housing comprising a functional portion and an actuator portion including a chamber; a canister within the chamber comprising an elongate body comprising an enclosed first end and an open second end, a cap welded to the open second end and including a penetrable or separable septum, thereby defining an interior cavity filled with pressurized and/or at least partially liquefied gas; a carriage movable within the housing from the first position, the carriage comprising a pin disposed adjacent the septum; and an actuator on the actuator portion coupled to the carriage such that initial activation of the actuator causes the carriage to move from the first position to a second position such that the pin opens the septum, thereby releasing pressurized gas from the canister into one or more passages within the tool.

The pin may include a blunt, e.g., beveled, tip that may be sized to open the septum. For example, a beveled tip may apply a more localized force to the septum, which may reduce the overall force needed to open the septum. The pin may have a diameter or other cross-section smaller than the septum, e.g., to allow gas to flow freely and/or quickly around the pin once the septum is opened.

Other aspects and features including the need for and use of the present disclosure will become apparent from consideration of the following description taken in conjunction with the accompanying drawings.

It will be appreciated that the exemplary apparatus and components thereof shown in the drawings are not necessarily drawn to scale, with emphasis instead being placed on illustrating the various aspects and features of the illustrated embodiments. The drawings illustrate exemplary embodiments, in which:.

Turning to the drawings, <FIG> and IB show an exemplary embodiment of intraocular lens (IOL) inserter <NUM> that includes a lens delivery portion <NUM>, an actuator <NUM>, and an energy device, e.g., canister <NUM>. The intraocular lens inserter <NUM> may include a main body portion <NUM>, which includes various cavities, recesses, and conduits, e.g., for providing communication between the canister <NUM> and the lens delivery portion <NUM>, e.g., for delivering a lens (not shown) from a lens compartment <NUM> loaded into or onto, secured to, or otherwise forming a part of the lens delivery portion <NUM>, e.g., as described in <CIT>. Alternatively, the actuator <NUM> and energy device, e.g., canister <NUM>, may be provided in other medical devices or tools, which may be actuated by releasing pressurized gas from the canister <NUM> to actuate a functional portion of the tool, similar to the methods described elsewhere herein. For example, the actuator <NUM> and canister <NUM> may be provided in a shunt inserter for glaucoma procedures, a syringe plunger pusher for liquid injections, or other tools (not shown).

For example, in the exemplary embodiment shown in <FIG> and <FIG>, the IOL inserter <NUM> may be provided with a canister <NUM> already provided within the housing <NUM>, i.e., secured within chamber <NUM>. Alternatively, the housing <NUM> may include a removable cap <NUM> allowing the canister <NUM> to be removed and replaced with a new canister, if desired. In the embodiment shown, the IOL inserter <NUM> includes a carriage <NUM> coupled to the actuator <NUM> and carrying a pin <NUM>. When the canister <NUM> is loaded into the chamber <NUM> (e.g., during manufacturing or before use, such as, for example, where the canister <NUM> may be loaded into the housing <NUM> via the cap <NUM> sometime prior to use), the pin <NUM> may be disposed adjacent a septum <NUM> of the canister <NUM>, as shown in <FIG>. In addition, the IOL inserter <NUM> may include an O-ring or other seal <NUM> disposed within the chamber <NUM> adjacent the pin <NUM>, which may slidably engage a neck <NUM> of the canister <NUM>, e.g., to provide a substantially fluid-tight seal between the neck <NUM> and the fluid passages within the IOL inserter <NUM>.

Optionally, the carriage <NUM> may be slidably disposed within the main body portion <NUM>, e.g., such that activation of the actuator <NUM>, as shown in FIG. IB, causes the carriage <NUM> and pin <NUM> to move axially, e.g., from the original or distal position shown in <FIG> proximally towards the canister <NUM> to the proximal position shown in FIG. IB, thereby puncturing the septum <NUM> with the pin <NUM> and allowing gas to escape from the canister <NUM>. Optionally, a spring or other biasing mechanism <NUM> may be provided within the main body portion <NUM>, e.g., within the chamber <NUM> adjacent the O-ring <NUM> and/or around the neck <NUM> of the canister <NUM>, for biasing the carriage <NUM> distally towards the distal position. Thus, when the actuator <NUM> is released, the carriage <NUM> may automatically return to the distal position and the pin <NUM> may be withdrawn from the septum <NUM>, as shown in <FIG>.

For example, <FIG> shows an exemplary embodiment of a pin <NUM> that may be carried by the actuator <NUM> (not shown in <FIG>). In this embodiment, the pin <NUM> includes a blunt, e.g., beveled tip 34a that may be sized to open a canister <NUM>. For example, a beveled tip 34a may apply a more localized force to a septum <NUM> of the canister <NUM> (e.g., the septum <NUM> shown in <FIG> and <FIG> and described further elsewhere herein), which may reduce the overall force needed to open the septum <NUM>, as described further elsewhere herein. The pin <NUM> may have a diameter or other cross-section smaller than the septum <NUM>, e.g., to allow gas to flow freely and/or quickly around the pin <NUM> once the septum <NUM> is opened, as described elsewhere herein.

In some instances, the lens compartment <NUM> may be a lens cartridge that may be loaded into the lens delivery portion <NUM>. In other instances, the lens compartment <NUM> may be fixedly attached to or form an integral part of the IOL inserter <NUM>. The IOL inserter <NUM> may be used to deliver a lens contained within the lens compartment <NUM> into a patient's eye. For example, the actuator <NUM> may be activated to deliver gas from the canister <NUM> through one or more passages of the main body portion <NUM>, e.g., to pressurize an incompressible fluid to deliver the lens from the lens delivery portion <NUM> during a cataract surgical procedure.

Turning to <FIG>, an exemplary embodiment of a canister <NUM> is shown. In some instances, the canister <NUM> may provide a single-use energy source for a medical device or other tool, such as the IOL inserter <NUM> of <FIG> and <FIG>. Generally, the canister <NUM> includes a body <NUM> and a cap <NUM> welded to the body <NUM> to provide an enclosed cavity <NUM> filled with a fluid, e.g., carbon dioxide. The fluid contained within the enclosed cavity <NUM> may be used to provide a desired potential energy or discharge force to the IOL inserter <NUM>, e.g., to advance the lens from the lens delivery portion <NUM>. In alternative embodiments, the canister <NUM> may be filled with other two-phase gases, such as a hydrofluorocarbon (e.g., HFC-134a), or a single-phase gas, such as nitrogen. As used herein, "pressurized gas" may include a single-phase gas or a two-phase gas, e.g., in which the gas has been at least partially liquefied, and so may include either a gaseous or mixed liquid-gaseous state fluid. The volume of the cavity <NUM> may be sufficient to provide energy to the medical device, e.g., a discharge force for the IOL inserter <NUM> that may be substantially constant and/or controlled when the actuator <NUM> is actuated. In an exemplary embodiment, the cavity <NUM> may have an interior volume of no more than about <NUM> milliliters (<NUM>), or not more than about one milliliter (<NUM>), e.g., between about <NUM>-<NUM>, or between about <NUM>-<NUM>. However, in other embodiments, the interior volume of the cavity <NUM> may be any desired volume. For example, in some instances, the interior volume of the cavity <NUM> may be greater than <NUM> or less than <NUM>.

In some embodiments, the body <NUM> and cap <NUM> are formed from stainless steel or other corrosion resistant, desired, or suitable metal, or other material. In some embodiments, one or more of the body <NUM> and cap <NUM> may be formed by one or more of drawing, stamping, machining, casting, molding, and the like. For example, with reference to <FIG>, the body <NUM> may be deep drawn from sheet metal, e.g., a round sheet metal blank of Type <NUM> stainless steel, using one or more dies and punches (not shown), e.g., to form a main barrel region <NUM> and enclosed base or first end <NUM> of the body <NUM>. Additional processing may be used to form a tapered shoulder region <NUM> and open neck region or second end <NUM> defining an opening or passage <NUM> communicating with an interior <NUM> of the body <NUM>. For example, the shoulder and neck regions <NUM>, <NUM> may be formed by necking and the like, such that the neck region <NUM> has a substantially uniform diameter smaller than the diameter of the main barrel region <NUM>. Alternatively, the neck region <NUM> may have a diameter similar to the main barrel region <NUM>, i.e., omitting the shoulder region <NUM>. The regions of the body <NUM> may be substantially radially symmetrical about a central axis <NUM> of the canister <NUM>. The neck region <NUM> may terminate in a substantially planar end wall 58a defining a plane substantially perpendicular to the axis <NUM>.

In an exemplary embodiment, the body <NUM> may have a length between the first end <NUM> and the end wall 58a of the neck region <NUM> that is less than about thirty millimeters (<NUM>), the outer diameter of the barrel region <NUM> may be not more than about ten millimeters (<NUM>) or not more than about eight millimeters (<NUM>), and the outer diameter of the neck region <NUM> may be not more than about five millimeters (<NUM>), or not more than about four millimeters (<NUM>). The neck region <NUM> may have a substantially uniform diameter length between about three to eight millimeters (<NUM>-<NUM>) or between about four to six millimeters (<NUM>-<NUM>), e.g., having sufficient length to accommodate the O-ring <NUM> and carriage <NUM> sliding along the neck region <NUM> during actuation of the IOL inserter <NUM>, as described elsewhere herein. However, the provided dimensions and shapes are merely examples. Thus, the various dimensions of the various aspects of the canister <NUM> may be selected to be any desired dimension. Further, the shapes of the various aspects of the canister may be any desired shape. For example, one or more shapes of one or more aspects of the canister may be radially asymmetrical relative to the central axis <NUM> of the canister <NUM>.

Similarly, as best seen in <FIG>, the cap <NUM> may be stamped, coined, drawn, and/or otherwise processed from another blank, e.g., to define an annular body <NUM> having a relatively thin closed or first end <NUM> and an open second end <NUM> also symmetrical about the axis <NUM>. The annular body <NUM> may have an outer diameter smaller than the neck region <NUM> of the body <NUM> such that the annular body <NUM> may be inserted into the opening <NUM> while providing a desired clearance between the annular body <NUM> and the neck region <NUM>, which facilitates projection welding the cap <NUM> to the body <NUM>, as described elsewhere herein.

The closed end <NUM> is formed to include a penetrable wall or septum <NUM> having a desired diameter and/or thickness for accessing the gas within the cavity <NUM> once the canister <NUM> is loaded into a medical device, as described further elsewhere herein. The septum <NUM> may have a substantially uniform thickness. For example, the septum <NUM> may have a wall thickness between about <NUM>-<NUM>. The septum <NUM> may have a wall thickness of not more than about <NUM>. The septum <NUM> may have a diameter between about <NUM>-<NUM>. The septum <NUM> may have a diameter of not more than about <NUM>. Although some exemplary dimensions are provided, the scope of the disclosure is not so limited. Rather, the dimensions and shapes of various aspects of the cap <NUM> may be any desired shape or dimension. For example, the various dimensions and shapes of the cap <NUM> may be selected based on the application of the cap <NUM> and/or canister <NUM>.

The septum <NUM> may be surrounded by thicker shoulder <NUM> to support the septum <NUM> while allowing the septum <NUM> to be penetrated during operation of a medical device. For example, the septum <NUM> may be penetrated during loading of the canister <NUM> into a medical device. Alternatively, the septum <NUM> may be penetrated some time after installation of the canister <NUM> into the medical device, such as, for example, during actuation of the medical device. For example, the septum <NUM> may be sized to engage the pin <NUM> of the IOL inserter <NUM> shown in FIG. IB when the canister <NUM> is loaded into the chamber <NUM> of the IOL inserter <NUM> such that the pin <NUM> easily punctures the septum <NUM> with a desired maximum puncture force when the actuator <NUM> is first activated. In some examples, the force needed to puncture the septum <NUM> may be not more than about one hundred Newtons (<NUM> N). Alternatively, the force needed to puncture the septum <NUM> may be not more than about eighty Newtons (<NUM> N). However, the force needed to puncture the septum <NUM> may be selected to be any desired force. Thus, the puncture force may be greater than eighty Newtons (<NUM> N) or greater than one hundred Newtons (<NUM> N). Upon puncture of the septum <NUM>, the gas within the canister <NUM> is controllably released during use of the IOL inserter <NUM>, as described elsewhere herein.

Alternatively, as shown in <FIG>, the septum <NUM> may be a generally circular disc or panel defining a first thickness surrounded by a relatively thin- walled perimeter 167b extending to the shoulder <NUM>, e.g. , similar to the septum <NUM> shown in <FIG> and <FIG> described elsewhere herein. The thickness of the perimeter 167b may be selected to facilitate separation of the septum <NUM> at least partially from the shoulder <NUM> when a predetermined puncture force is applied to the septum <NUM>, e.g., not more than about eighty Newtons (<NUM> N) or otherwise similar to the other embodiments described elsewhere herein.

The second end <NUM> of the cap <NUM> includes an annular flange <NUM> extending radially outwardly relative to the annular body <NUM>, e.g. , substantially perpendicular to the axis <NUM>, thereby defining a lower surface 69a adjacent the annular body <NUM> and an upper surface 69b opposite the lower surface 69a. The lower surface 69a may be substantially planar and may include an annular projection <NUM> that is spaced apart from the annular body <NUM> and from an outer edge 69c of the annular flange <NUM>. In some embodiments, the projection <NUM> may extend entirely around the annular body <NUM> along the lower surface 69a. In some embodiments, the projection <NUM> may be continuous. In other embodiments, the projection <NUM> may be discontinuous. In an exemplary embodiment, the projection <NUM> may taper from the lower surface 69a and terminate in a substantially planar end surface 70a, e.g. , having a height between about <NUM>-<NUM>, e.g., about <NUM>. Alternatively, as shown in <FIG>, the projection <NUM> may be omitted and the lower surface 169a of the annular flange <NUM> may be positioned immediately against the end wall 58a of the neck region <NUM>, as described elsewhere herein.

Once formed, the body <NUM> and cap <NUM> may be further processed, e.g., deburred, have sharp edges broken, and the like, to provide, for example, a desired finish for the components before assembly.

The cap <NUM> may be substantially permanently attached to the body <NUM>, e.g., by projection welding. For example, in an exemplary process, the body <NUM> and cap <NUM> may be placed in a filling chamber (not shown) and the filling chamber may be filled with carbon dioxide (or other gas) to a desired pressure, thereby filling the interior <NUM> of the body <NUM> with the C02. The filling chamber may be controlled to a desired temperature such that it is below the saturation temperature of the gas at filling pressure to condense the gas in the canister <NUM>, thus filling the canister <NUM> with liquefied gas.

Once filled, the cap <NUM> may be welded to the neck region <NUM> to close the interior <NUM> and seal the liquid C02 within the resulting canister <NUM>. For example, the first end <NUM> of the annular body <NUM> may inserted into the passage <NUM> in the neck region <NUM> such that the wall of the annular body <NUM> is spaced apart from the inner surface of the neck region <NUM>, e.g. , until the end surface 70a of the projection <NUM> contacts the end wall 58a of the neck region <NUM>. In this manner, when the cap <NUM> is welded to the body <NUM>, the resulting weld may be formed between the projection <NUM> and the end wall 58a of the neck region <NUM>. For example, in an exemplary projection welding procedure, the body <NUM> may be coupled to ground (or one electrode) within the filling chamber and an opposite electrode may be placed against the upper surface 69b of the annular flange <NUM> on the cap <NUM>, thereby holding the projection <NUM> against the end wall 58a of the neck region <NUM>. Once the body <NUM> and cap <NUM> are engaged, electrical energy may be applied to the electrode, thereby forming a weld to attach the cap <NUM> and seal the resulting cavity <NUM> of the canister <NUM> with a desired volume of liquid C02 therein.

In another, unclaimed, alternative, instead of the annular body <NUM>, the septum may be formed within the same plane as the annular flange <NUM>, which may have an outer diameter that is larger than the neck region <NUM> of the body <NUM>, and an outer lip or flange may be provided (not shown) around the annular flange <NUM> sized to be received over the neck region <NUM>. In this alternative, instead of inserting the annular body of the cap into the open second end, the outer lip or flange may be positioned over the open second end and welded to the neck region <NUM>, e.g., similar to a bottle cap, except including a separable septum, such as any of the embodiments described herein.

When the canister <NUM> is removed from the filling chamber, the C02 may return to its gaseous state or a mixed liquid-gaseous state, thereby providing a desired pressure within the cavity <NUM>. In an exemplary embodiment, the mass of C02 provided within the canister <NUM> after filling may be about six hundred milligrams (<NUM>) or less, or about five hundred milligrams (<NUM>) or less and/or having a resulting density between about <NUM>-<NUM>/L or between about <NUM>-<NUM>/L. In still other embodiments, the mass and/or density of the fluid, such as C02, within the canister <NUM> may be selected to be any desired mass or density. Further, it will be appreciated that gases or fluids other than C02 may be used to fill the canister <NUM> that provide a desired pressure and/or discharge force during use, as desired.

Turning to <FIG> and <FIG>, another embodiment of a cap <NUM> is shown that may be formed using similar materials and methods as the cap <NUM>, e.g., drawn from a blank to define an annular body <NUM> having a relatively thin closed or first end <NUM> and an open second end <NUM>. The annular body <NUM> may have an outer diameter smaller than the neck region <NUM> of the body <NUM> such that the annular body <NUM> may be inserted into the opening <NUM> while providing a desired clearance between the annular body <NUM> and the neck region <NUM>, which facilitates projection welding the cap <NUM> to the body <NUM>, as described elsewhere herein.

The closed end <NUM> is formed to include a separable wall or septum <NUM> having a desired diameter and/or thickness for accessing the gas within the cavity <NUM> once the canister <NUM> is loaded into a medical device (not shown), as described further elsewhere herein. For example, as shown in <FIG> and <FIG>, the septum <NUM> may include a relatively thicker central region 167a at least partially surrounded by a relatively thin perimeter 167b. Optionally, the perimeter 167b may completely surround the central region 167a or may extend only partially around the central region 167a, e.g., to provide a preferential hinge, as explained further elsewhere herein. Optionally, the central region 167a may have a dome shape, e.g., as best seen in <FIG> or may have a substantially uniform thickness that is substantially thicker than the perimeter 167b. Alternatively, the cap <NUM> may include a relatively thin- walled septum <NUM>' similar to the cap <NUM>, e.g., as shown in <FIG>, or the cap <NUM> shown in <FIG> may include a thin perimeter surrounding a thicker central region (not shown).

The septum <NUM> may be surrounded by a relatively thicker shoulder <NUM> to support the septum <NUM> while allowing the septum <NUM> to be at least partially separated from the shoulder <NUM> during operation of a medical device. The septum <NUM> is configured to be pressed inwardly to cause the perimeter 167b to tear or otherwise separate at least partially between the central region 167a and the shoulder during or after loading of the canister <NUM> into a medical device, as described elsewhere herein. For example, as shown in <FIG>, a pin <NUM> may be provided that includes a beveled tip 34a, which may apply a localized force against one side of the septum <NUM>, which may enhance separation of the septum <NUM> at least partially from the shoulder <NUM>. The pin <NUM> may have a diameter smaller than the outer perimeter of the septum <NUM>, e.g., to facilitate gas flowing freely from the canister <NUM> around the pin <NUM> once the septum <NUM> is at least partially separated from the shoulder <NUM>.

The second end <NUM> of the cap <NUM> includes an annular flange <NUM> extending radially outwardly relative to the annular body <NUM>, e.g., substantially perpendicular to the axis <NUM>, thereby defining a lower surface 169a adjacent the annular body <NUM> and an upper surface 169b opposite the lower surface 169a. The lower surface 169a may be substantially planar and may include an annular chamfer <NUM> that transitions from the lower surface 169a to the second end <NUM> of the annular body <NUM>, e.g., to provide a welding interface for attaching the cap <NUM> to the body <NUM>, as described further elsewhere herein.

Optionally, the annular body <NUM> may include one or more radial projections <NUM>, e.g., a plurality of projections <NUM> spaced apart around the circumference of the second end <NUM>. The projections <NUM> may be sized to contact the inner surface of the neck region <NUM> immediately adjacent the end wall 58a (shown in <FIG>) to hold the cap <NUM> stationary and/or centered on the neck region <NUM> during attachment. In addition or alternatively, the annular body <NUM> may include one or more grooves or passages <NUM> in the outer surface of the annular body <NUM>, e.g., a plurality of passages <NUM> extending between the first and second ends <NUM>, <NUM>, which may facilitate gas entering the interior of the canister <NUM> during filling.

For example, with additional reference to <FIG>, the first end <NUM> of the cap <NUM> may be inserted into the passage <NUM> in the neck region <NUM> of the body <NUM> until the flange <NUM> contacts the end wall 58a of the neck region <NUM>. The projections <NUM> (not shown in <FIG>) may hold the cap <NUM> in place and/or center the cap <NUM> within the passage <NUM>.

Similar to other methods herein, in an exemplary process, the body <NUM> and cap <NUM> may be placed in a filling chamber (not shown) and the filling chamber may be filled with carbon dioxide (or other gas) to a desired pressure, thereby filling the interior <NUM> of the body <NUM> with the CO2. The passages <NUM> may facilitate the gas passing by the cap <NUM> into the interior <NUM>.

Once filled, the cap <NUM> may be welded to the neck region <NUM> to close the interior <NUM> and seal the liquid CO2 within the resulting canister <NUM>. For example, the first end <NUM> of the annular body <NUM> may inserted into the passage <NUM> in the neck region <NUM> such that the wall of the annular body <NUM> is spaced apart from the inner surface of the neck region <NUM>, e.g., until the lower surface 169a of the flange <NUM> contacts the end wall 58a of the neck region <NUM>. Once the body <NUM> and cap <NUM> are engaged, electrical energy may be applied to electrodes (not shown) coupled to the cap <NUM> and body <NUM>, thereby forming a weld to attach the cap <NUM> and seal the resulting cavity <NUM> of the canister <NUM> with a desired volume of liquid CO2 therein. When the cap <NUM> is welded to the body <NUM>, the chamfer <NUM> may localize the resulting weld to the inner perimeter of the neck region <NUM>, provide line contact to localize weld current to enable a consistent weld, may center the cap <NUM> in the neck region <NUM>, and/or reduce flaring of the outer neck diameter. Optionally, it will be appreciated that other features may be provided on the cap <NUM> to create a concentrated flow of current at desired locations of the cap <NUM> and/or neck <NUM> to enhance resistance welding of the cap <NUM> to the neck <NUM>.

Optionally, after the canister <NUM> is removed from the filling chamber, the canister <NUM> may be weighed to confirm that a desired amount of gas has been loaded into the canister <NUM>. For example, the mass and pressure of the gas may be determined by comparing the mass after filling with the original mass of the body <NUM> and cap <NUM>, e.g., to confirm that the mass and pressure lie within desired tolerances. For example, it may be desirable to confirm that the pressure within the canister <NUM> does not exceed a desired maximum density (e.g., <NUM>/mL), which may otherwise result in the canister <NUM> exceeding regulatory standards and/or safe pressures. Again, the density and/or mass of the fluid contained within the canister <NUM> may be any desired density or mass.

During subsequent storage of the canister <NUM> (e.g., during its normal shelf life before being loaded into and used with a medical device), it may be desirable to confirm that gas has not leaked from the canister <NUM> during its intended shelf life. For example, the canister <NUM> may be weighed again, e.g., at one or more desired intervals, to ensure that the gas has not leaked from the canister <NUM>. Alternatively, other methods may be used to confirm that gas remains within the canister <NUM>, e.g., mass spectrometry and the like. For example, despite the cap <NUM> being welded to the body <NUM>, gas may still leak from the canister <NUM> and, therefore, the canister <NUM> may be weighed to ensure that an adequate fill of gas remains to ensure sufficient gas through the stroke of the medical device into which the canister <NUM> is to be loaded. One approach is to weigh the canister <NUM> following filling; expose the canister <NUM> to elevated temperatures to raise the internal pressure to accelerate any leakage that may be present; reweigh the canister <NUM> to determine if the mass has been reduced indicating the leak; and then extrapolate the leakage rate over the shelf life to ensure that sufficient gas will remain in the canister <NUM> over the shelf life of the product.

Forming the body <NUM> and cap <NUM> from stainless steel may provide corrosion protection for the resulting canister <NUM> over its target shelf life. Galvanized steel has been used for conventional gas canisters to provide corrosion protection, but may be inadequate for the canister <NUM>. In particular, metallic plating, e.g., zinc, cannot be applied before welding the cap <NUM> to the body <NUM> since the plating would be lost at the weld, thereby compromising the corrosion protection. If additional plating were applied to the weld, the plating may not have a uniform thickness (on each canister and between different canisters). However, it will be appreciated that any appropriate and/or desired material, such as metal, plastic, and/or composite materials, may be used instead of stainless steel or galvanized steel.

Such variances in plating (before or after welding) may not meet the required tolerances to ensure that the mass and/or pressure of the gas within the finished cylinder falls within the desired range. Stainless steel can be formed to higher tolerances since no such plating is needed, thereby ensuring that the properties of the gas may be accurately determined after filling and/or over the shelf life of the canister.

Subsequently, during manufacturing, the canister <NUM> may be loaded into a medical device to provide an energy source that may be controllably released to provide a desired discharge force to operate the medical device. As explained above, in some embodiments, the energy source may be pressurized CO2. For example, in some embodiments, the IOL inserter <NUM> may be provided to the user with the canister <NUM> pre-loaded within the chamber <NUM> of the housing <NUM>. Thus, in some instances, a medical device pre-loaded with the canister <NUM> may be a disposable, single-use device. In some embodiments, the cap <NUM> may be substantially permanently coupled to the housing <NUM>, e.g., by bonding with adhesive, sonic welding, interference fit, one or more connectors, and the like (not shown) to prevent the cap <NUM> and canister <NUM> from being removed by the user.

Alternatively, the IOL inserter <NUM> may be a reusable device, e.g., in which the user may load one or more canisters <NUM> successively into the housing <NUM>, as desired. For example, with the IOL inserter <NUM> shown in <FIG> and <FIG>, the user may remove the cap <NUM> and load a canister <NUM> into the chamber <NUM> of the main body portion <NUM> of the IOL inserter <NUM>, e.g., such that the septum <NUM> of the cap <NUM> is disposed adjacent the pin <NUM>, as shown in <FIG>. The cap <NUM> may then be reconnected to the main body portion <NUM> to secure the canister <NUM> within the housing <NUM>.

At any time, the actuator <NUM> may be activated to direct the carriage <NUM> proximally to the proximal position shown in FIG. IB such that the pin <NUM> penetrates the septum <NUM>, thereby delivering C02 from the canister <NUM> into one or more passages of the IOL inserter <NUM>. Alternatively, in the embodiment shown in <FIG> and <FIG>, the perimeter 167b of the septum <NUM> may tear or otherwise separate at least partially around the central region 167a, thereby delivering C02 from the canister <NUM>. The released C02 may be used to pressurize an incompressible liquid, e.g., silicone oil, within the housing <NUM>. The pressurized incompressible liquid may be used to deliver a lens from the lens compartment <NUM>. The O- ring seal <NUM> may slide along the neck region <NUM> and prevent C02 from leaking into the chamber <NUM> or elsewhere other than the intended passages within the IOL inserter <NUM>. The actuator <NUM> may then be released, allowing the carriage <NUM> to return to the distal position shown in <FIG>.

In embodiments in which the lens compartment <NUM> defines a separate lens cartridge, the lens compartment <NUM> may loaded into the lens delivery portion <NUM> (or may already be loaded). However, as explained above, the lens compartment <NUM> may be fixedly attached to the main body portion <NUM> or form an integral portion thereof. The actuator <NUM> of the IOL inserter <NUM> may be activated at any time to controllably deliver the incompressible fluid under constant pressure from the C02, e.g., silicone oil, to deliver the lens from the lens compartment <NUM>. For example, the actuator <NUM> may be selectively actuated such that the flow rate of the incompressible liquid is proportional to the extent the actuator <NUM> is activated, e.g., to advance the lens from the lens compartment <NUM> at a controlled speed.

After the procedure, the entire IOL inserter <NUM> may be disposed of or, if reusable, the canister <NUM> may be removed, the medical device may be cleaned and/or otherwise prepared for another procedure, at which time another canister may be loaded into the medical device.

Although the gas canisters herein have been described for use with an IOL inserter, it will be appreciated that the gas canisters may be used with other medical devices. For example, the gas canisters may be used within a syringe device, such as that disclosed in <CIT>. For example, such a syringe device may include a needle or other cannula that may be used to deliver viscous or other fluids contained within the device into an eye, with the gas canister providing a discharge force that may be controlled by an actuator of the syringe device to controllably deliver the fluid into an eye. In another embodiment, the gas canisters may be used to deliver a tubular shunt or other implant (not shown) into an eye or other region of a patient's body.

It is fully contemplated that the features, components, and/or steps described with respect to one or more embodiments, methods, or Figures may be combined with the features, components, and/or steps described with respect to other embodiments, methods, or Figures of the present disclosure.

Claim 1:
A single-use canister (<NUM>) suitable for loading into a medical device or other tool, comprising:
an elongate body (<NUM>) comprising a barrel region (<NUM>) defining a first diameter, an enclosed first end (<NUM>), and a neck region (<NUM>) extending from the barrel region to an open second end defining an end wall (58a), the elongate body defining a central axis (<NUM>) extending between the first end and the second end; and
a cap (<NUM>) comprising an annular portion (<NUM>) including a closed first end (<NUM>) and an open second end (<NUM>), a penetrable or separable septum (<NUM>) formed in the first end of the cap, and an annular flange (<NUM>) extending radially from the second end of the annular portion of the cap, thereby defining a lower surface (169a) defining a plane substantially perpendicular to the central axis, the septum comprising a relatively thicker central region (167a) and a relatively-thin perimeter (167b) at least partially surrounding the central region and configured to tear inwardly to at least partially separate the central region from the cap,
the first end of the annular portion of the cap inserted into the open second end of the elongate body such that the annular portion is spaced from an interior surface of the neck region and the septum is disposed within the neck region, the annular flange secured to the end wall of the second end of the elongate body, thereby enclosing a cavity,
the cavity filled with pressurized and/or at least partially liquefied gas.