Devices, systems and methods for delivering gases - Patents.com

Abstract

Devices and methods for delivering gas are provided. In one example, the device includes a syringe body including a proximal end, a distal end including an outlet, and a gas chamber in communication with the outlet, and a plunger carrying a piston slidably received within the syringe body. A canister containing gas is provided within the plunger adjacent a passage through the piston that communicates with the gas chamber. A drive actuator is movable such that an opener pin opens a septum of the canister to release gas through the passage and into the gas chamber, thereby displacing the piston proximally to fill the gas chamber. Upon actuation, the plunger can be advanced to deliver gas within the gas chamber through the outlet into a patient's body, for example, into the eye, via a cannula connected to the outlet.

Description

[Technical field]

[0001] The present application relates to devices, systems and methods for delivering medicaments into a patient's body, and more particularly to injectors for delivering gases, e.g., premixed gases, e.g., into a patient's eye, and systems and methods for using such injectors.

[0002] Related Application Data This application claims the benefit of co-pending U.S. Provisional Application No. 63 / 220,917, filed July 12, 2021, the entire disclosure of which is expressly incorporated herein by reference. [Background technology]

[0003] Various devices are available for delivering the mixed gases into the patient's body, for example, to the inside of the eye during vitreous surgery. For example, a reusable gas cylinder can be used to manually mix and fill the syringe used to deliver the mixed gas. However, such manual mixing systems are complex, including multiple components, such as one or more filters, tubing, stopcocks, etc., to transfer the gases to be mixed from the cylinder into the syringe. They also require multiple operators, typically a circulating nurse and a cleaning technician, to coordinate the filling process, and may include multiple purge cycles prior to gas filling. They also require manual calculations of the gas and air volumes to provide the desired gas / air mixture, with the risk of injecting an inaccurate gas mixture, such as a thick gas mixture, into the patient's body.

[0004] Systems are available that attempt to semi-automate the purging and gas filling of syringes, but still require the user to manually calculate the desired gas and air volumes to provide the desired gas / air mixture.

[0005] Thus, devices, systems and methods that facilitate the delivery of gas into a patient's body would be useful. Summary of the Invention

[0006] The present invention relates to devices, systems and methods for delivering medicaments into a patient's body, and more particularly to injectors for delivering gases, such as premixed gases, into a patient's eye, and systems and methods for using such injectors.

[0007] In one example, the devices and systems herein can be provided to a user as a ready-to-use and / or disposable syringe system for delivering a premixed gas, such as twenty percent (20%) sulfur hexafluoride (SF6) or fourteen percent (14%) perfluoropropane (C3F8). The device can include an internally contained source, such as a gas canister, filled with the premixed gas and / or can perform automatic syringe purging and filling upon actuation.

[0008] The device may provide one or more advantages over conventional systems. For example, in one example, the device may be used immediately after activation since premixed gas is incorporated within the device, i.e., via a gas canister. The device herein may also improve the accuracy of the mix ratio and / or reduce risk since manual gas mixing is eliminated. The device may also maintain sterility and / or require only a single user, as compared to, for example, manual mixing systems. Furthermore, given the self-contained nature of the device, an external gas source and / or other equipment or supplies may not be required.

[0009] According to one example, a system for delivering gas into a patient's body is provided, the system comprising: a barrel including a proximal end, a closed distal end including an outlet, a longitudinal axis extending between the proximal and distal ends, and a gas chamber in communication with the outlet; a plunger slidably received within a syringe body, the plunger including a piston within the barrel adjacent the distal end and a handle extending from the proximal end of the syringe body; a canister containing gas within the plunger adjacent a passage through the piston in communication with the gas chamber, the canister including a septum adjacent an opener pin; and a drive actuator including a first end adjacent the handle and a second end within the plunger adjacent the canister, the drive actuator movable to move the second end distally to cause the opener pin to release gas from the canister, whereby gas moves through the passageway and into the gas chamber, thereby displacing the piston proximally along the axis to fill the gas chamber with gas.

[0010] According to another example, a method of preparing an injection device is provided, the method comprising the steps of providing a barrel including a proximal end, a closed distal end including an outlet, and a gas chamber in communication with the outlet, a plunger slidably received within the barrel including a piston within the barrel adjacent the distal end, a gas canister filled with gas, a handle on the proximal end of the syringe body, and a drive actuator; and actuating the drive actuator to cause an opener pin to open a septum of the gas canister to release gas from the canister, whereupon gas passes through the piston into the gas chamber, thereby displacing the piston proximally and filling the gas chamber with gas.

[0011] According to yet another example, a method for delivering gas into a patient's body is provided, the method comprising the steps of providing a barrel including a proximal end, a closed distal end including an outlet, and a gas chamber in communication with the outlet, a plunger slidably received within the barrel including a piston within the barrel adjacent the distal end, a gas canister filled with gas, a handle extending from the proximal end of the syringe body, and a drive actuator; actuating the drive actuator to cause an opener pin to open a septum of the gas canister to release gas from the canister, whereupon gas passes through the piston into the gas chamber, thereby displacing the piston proximally to fill the gas chamber with gas; introducing a tip of a cannula or needle in communication with the outlet into the patient's body; and advancing the plunger to deliver gas in the gas chamber into the patient's body via the outlet.

[0012] Other aspects and features of the present invention will become apparent from consideration of the following description taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0013] The invention will be better understood from the following description of specific examples taken in conjunction with the accompanying drawings, in which like reference numbers identify the same elements, and in which: [Figure 1] 1A and 1B are perspective and side views, respectively, of an example of a premixed gas delivery device. [Diagram 2] Figures 2A and 2B are longitudinal cross-sectional views of the device of Figures 1A and 1B before initial actuation, Figure 2C is a longitudinal cross-sectional view of the device of Figures 1A and 1B after initial actuation, and Figure 2D is a detailed view of the device of Figures 1A and 1B showing the flow path of gas delivered from a gas canister into a gas chamber of the device after actuation. [Diagram 3] 3A and 3B are perspective and side views, respectively, of another example of a premixed gas delivery device. [Figure 4]Figures 4A and 4B are longitudinal cross-sectional views of the device of Figures 3A and 3B before and after initial actuation, respectively, and Figure 4C is a detailed view of the device of Figures 3A and 3B showing the flow path of gas delivered from the gas canister into the gas chamber of the device after actuation. [Diagram 5] 5A-5C are detailed views of an alternative device including a pawl and ratchet mechanism.

[0014] The drawings are not intended to be limiting in any way, and it is contemplated that various examples of the invention may be embodied in other various ways, including those not necessarily depicted in the drawings. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several aspects of the invention and, together with the detailed description, serve to explain the principles of the invention, although it should be understood that the invention is not limited to the precise arrangements shown. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The following description of specific examples of the present invention should not be used to limit the scope of the present invention. Other examples, features, aspects, embodiments and advantages of the present invention will become apparent to those skilled in the art from the following description, which is an example of one of the best modes conceivable for carrying out the present invention. As will be understood, the present invention is also capable of various other obvious modes without departing from the present invention. For this reason, the drawings and description should be regarded as illustrative in nature and not restrictive.

[0016] Before describing the embodiments, it is to be understood that the invention is not limited to particular embodiments described, as such may, of course, vary, and the scope of the present invention will be limited only by the appended claims. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.

[0017] Where a range of values ​​is given, it is understood that each intervening value between the upper and lower limits of that range, to the tenth of the unit of the lower limit, is also specifically disclosed unless the context clearly dictates otherwise. Each smaller range between any stated value or intervening value in a stated range and any other stated value or intervening value in a stated range is encompassed within the invention. The upper and lower limits of such smaller ranges may each be independently included or excluded within the range, and each range is encompassed within the invention, whether or not both or either are included in the smaller range, subject to the specifically excluded limit in the stated range. Where a stated range includes one or both of the limits, ranges excluding either or both of those included limits are also intended to be included within the invention.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, some possible exemplary methods and materials are described herein.

[0019] It should be noted that, as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, a reference to a "compound" includes a plurality of such compounds, and a reference to a "polymer" includes a reference to one or more polymers and equivalents thereof known to those skilled in the art.

[0020] In this specification, certain ranges are indicated by the term "about" before the numerical values. The term "about" is used in this specification to provide literal support for the exact numerical value following the term and for a numerical value close to or close to the numerical value following the term. In determining whether a numerical value is close to or close to a specifically stated numerical value, the close or close unstated numerical value may be a numerical value that provides a substantial equivalent to the specifically stated numerical value in the context in which it is presented.

[0021] 1A and 1B show an example of a device or system 8 for delivering gas into a patient's body, e.g., about twenty percent (20%) sulfur hexafluoride (SF6) or about fourteen percent (14%) perfluoropropane (C3F8) premixed gas into a patient's eye (not shown). The device 8 generally includes a syringe body or barrel 10 having an open proximal end 12 and a closed distal end 14 defining a longitudinal axis 18 therebetween, and a gas chamber or interior 16 in communication with an outlet 15 at the distal end 14, which may be automatically filled with premixed gas upon actuation for delivery into the eye, e.g., as further described elsewhere herein.

[0022] An elongated plunger 20 is slidably received within the barrel 10 and includes a proximal end 22, e.g., extending proximally from the proximal end 12 of the barrel 10, and a distal end 24 carrying a piston 28 slidable along the inner surface of the barrel 10, e.g., including one or more O-rings or other seals 28a for maintaining a fluid-tight seal at the proximal end of the gas chamber 16. As shown in FIGS. 2A and 2B, the plunger 20 may be initially provided in a distal position with the piston 28 immediately adjacent the distal end 24 of the barrel 20, e.g., to minimize the interior volume of the gas chamber 16. As described further below, upon actuation of the device 8, the plunger 20 may automatically move axially within the barrel 10, i.e., proximally toward a proximal position as shown in FIG. 2C, as gas fills the gas chamber 16.

[0023] A canister 40 containing the premixed gas is provided within the plunger 20, e.g., in a cavity 26 adjacent the distal end 24 of the plunger 20 in fluid communication with the gas chamber 16 via one or more passages (one passage 48a is shown) through the piston 28. The canister 40 generally includes an elongated body 42 having a closed first end and an open second end having a cap 44 welded or otherwise attached to the second end to seal the interior 46 of the canister 40. The cap 44 includes a septum 44a that can be penetrated or otherwise opened, e.g., by an opener pin 36a, as further described elsewhere herein. For example, the septum 44a may include, e.g., a thin-walled or weakened region extending at least partially around a periphery of the cap 44, or a relatively thin central region (not shown), and the pin 36a may be a puncture pin including an angled tip configured to tear the septum 44a. Alternatively, the puncture pin may include a pointed, sharp or other tip (not shown) configured to pierce or tear the septum 44a. In a further alternative, the septum may be formed using other sealing members that may be pierced or displaced by the opener pin 36a to release gas in the interior 46.

[0024] The interior 46 can be filled with gas at a desired pressure, such that upon actuation of the device 8, the gas chamber 16 automatically fills with gas, as further described elsewhere herein. An example of a canister that may be included in the devices and systems herein is disclosed in U.S. Patent No. 10,610,351, the entire disclosure of which is expressly incorporated herein by reference.

[0025] In the example shown in FIGS. 2A-2C, for example, the canister 40 may be received in the cavity 26 through an opening in the piston 28, such that the septum 44a faces proximally. For example, the piston 28 may include a tubular extension 28b that extends proximally within the plunger 20 and defines a wall having a similar contour to the wall of the cavity 26, such as the body 42 of the canister 40. The extension 28b may be integrally molded or otherwise formed with the piston 28 and fixed relative to the plunger 20 such that the piston 28 and the canister 40 in the cavity 26 are coupled to the movement of the plunger 20. Alternatively, the cavity may be formed in the distal end 24 of the plunger 20, and the piston 28 may be a separate member (not shown) attached to the distal end 24. Optionally, the walls of cavity 26 may include one or more ribs, tabs, etc. (not shown) to support canister 40, e.g., prevent lateral movement, while at the same time providing a flow path for premixed gas around canister 40.

[0026] In the example shown in Figures 2A-2D, a cap 48 can be attached to the piston 28, e.g., during manufacturing or other final assembly, to seal the cavity 26 and prevent removal or other axial movement of the canister 40. The cap 48 can include a passageway 48a through the cap for delivery of premixed gas in the cavity 26 into the gas chamber 16. The cap 48 can be substantially permanently attached to the piston 28, e.g., using one or more of adhesive bonding, sonic welding, and one or more connectors, e.g., cooperating grooves, detents, screws, etc. (not shown). Figure 2D shows a series of arrows representing an exemplary flow path of premixed gas from the interior 46 of the canister 40 (through the open septum 44a), through the cavity 26 around the body 42 of the canister 40, and into the gas chamber 16 via the passageway 48a.

[0027] The plunger 20 also includes therein, for example, a drive actuator shaft 30 slidably disposed within a chamber 38 extending between the proximal and distal ends 22, 24 of the plunger 20. The shaft 30 includes a first or proximal end 32 disposed adjacent the proximal end 22 of the plunger 20 and a second or distal end 34 disposed adjacent the canister 40. An element 36 is carried at the second end 34 for opening a septum 44a, for example an opener pin 36a extending distally from the second end 34, the opener pin 36a extending through an opening 28c in the tubular extension 28b that houses the canister 40 so as to be initially spaced from the septum 44a of the canister 40. The distal end 34 of the shaft 30 and / or the tubular extension 28b may include one or more seals (not shown), for example, to prevent gas released from the canister 40 from passing proximally into the chamber 38 of the plunger 20.

[0028] The drive actuator shaft 30 can, for example, be movable distally within the chamber 38 of the plunger 20 to move the second end 34 distally, thereby causing the opener pin 36a to open the septum 44a to release the premixed gas from the canister 40. For example, the drive actuator shaft 30 can be initially restrained in a proximal position, i.e., with the opener pin 36a spaced proximally from the septum 44a, as shown, for example, in FIG. 2A, but biased to move distally within the plunger 20 toward a distal position, as shown, for example, in FIG. 2B. Upon actuation of the device 8, the shaft 30 can automatically move axially toward the distal position shown in FIG. 2B to cause the opener pin 36a to open the septum 44a to release the mixed gas therein, thereby filling the gas chamber 16, as further described elsewhere herein.

[0029] For example, as shown, device 8 may include a handle 50 on the proximal end 22 of barrel 10, i.e., the handle is substantially stationary relative to barrel 10, and an activation button 60 on handle 50 that is coupled to drive actuator shaft 30 and is actuated by a user to release shaft 30. In the example shown in FIGS. 1A-2B , handle 50 includes a pair of finger grips, wings or other features 52 extending transversely from proximal end 22 relative to axis 18, e.g., to facilitate holding and manipulating device 8 during use. Activation button 60 is attached to handle 50 such that, for example, a user may use their thumb to press button 60 while gripping grip 52 with index and middle fingers.

[0030] 2B and 2C, the button 60 is coupled to a locking member 62 that extends partially into the handle 50, e.g., around the barrel 20, and is initially coupled to the drive actuator shaft 30 to lock the shaft 30 in its initial proximal position. For example, the locking member 62 may include a detent tab or other feature 64 that is received in a recess, slot or other corresponding feature 33 in the proximal end 32 of the drive actuator shaft 30, e.g., through an opening 22a in the wall of the plunger 20, to prevent movement of the shaft 30. A spring or other resilient member 66 may be provided at the proximal end 22 of the plunger 20, e.g., between the proximal end 32 of the shaft 30 and the closed end 23 of the plunger 20, to bias the shaft 30 to move distally in the absence of the locking member 62. When the activation button 60 is depressed, for example, laterally relative to the longitudinal axis 18, the locking member 62 can move to release the features 64, 33, and in so doing, the spring 66 automatically directs the shaft 30 distally, causing the opener pin 36a to open the septum 44a and allow the premixed gas in the canister 40 to pass through the flow passage and into the gas chamber 16. For example, as shown in Figures 2B and 2C, depression of the activation button 60 causes the detent 64 to move laterally out of the recess 33 in the plunger 30, thereby releasing the plunger 30 and allowing the spring 66 to advance the plunger 30 distally.

[0031] As the premixed gas is released from the interior 46 of the canister 40, the piston 28 and plunger 20 may be displaced axially, i.e., proximally, within the barrel 10 as the gas chamber 16 fills with the premixed gas, for example, automatically under the pressure of the premixed gas in the canister 40. Additionally, as the gas chamber 16 fills with the premixed gas, the pressure of the premixed gas may expel any residual air within the gas chamber 16 through the outlet 15. The pressure and / or volume of the premixed gas in the canister 40 fills the gas chamber 16 to a preset volume, and excess gas is vented through the outlet 15 to obtain the volume at atmospheric pressure. In one example, the pressure of the premixed gas in the canister 40 may be set such that the gas chamber 16 is filled with approximately fifty milliliters (40 mL) of premixed gas at atmospheric pressure, with the only action required from the user being to press the activation button 60.

[0032] Optionally, a filter 29 can be provided adjacent the outlet 15, for example against or in the distal wall 14 of the barrel, or in the gas chamber 16, for filtering the premixed gas exiting the gas chamber 16 via the outlet 15. This filter 29 can have a pore size of about 0.22 μm or less, for example, to filter out bacteria so that the gas is considered sterile. Alternatively, a separate filter can be attached to the outlet 15, for example to a luer fitting or other connector provided at the distal end 14 of the barrel 10.

[0033] Once device 8 is actuated to fill gas chamber 16 with the mixed gas, a needle or other cannula (not shown) can be connected to distal end 14 of barrel 10 to allow delivery into the patient's body, e.g., to a luer fitting or other connector at distal end 14 that communicates with outlet 15. Alternatively, a needle or other cannula can be integrally provided at distal end 14 of barrel 10, if desired, e.g., molded into barrel 10 or otherwise permanently attached to the barrel.

[0034] Optionally, barrel 10 can include one or more segments that indicate the volume of gas in gas chamber 16 that has been delivered to the patient. For example, as plunger 20 retracts during filling, piston 28 can automatically align with "0" or other initial volume indicator. A user can then deliver premixed gas from gas chamber 16 into the patient's body by simply depressing plunger 20, e.g., by pressing thumb rest or other feature 23a on proximal end 22, and the segments can be used to verify the volume delivered.

[0035] Alternatively, other actuation configurations may be provided. For example, referring to Figures 3A-4C, another example of a device 108 is shown that includes a barrel 110, a plunger 120 with a piston 128, a drive actuator shaft 130, and a canister 140, generally similar to device 8 (with similar features numbered by 100). However, in this example, an opener pin 136 is provided that is attached to the piston 128, i.e., an opener pin 144a is located distal to the canister 140, faces proximally, and is substantially stationary relative to the plunger 120. The canister 140 is arranged such that the septum 144a faces distally, but is initially spaced from the opener pin 144a. For example, the canister 140 is received within the cavity 126 of the tubular extension 128b, which is integrally formed with or otherwise extends proximally from the piston 128 within the chamber 138 of the plunger 120, as in device 8. However, in this device 108, the canister 140 is axially movable within the chamber 126.

[0036] For example, the canister 140 can be initially disposed within the chamber 126 such that the septum 144a is spaced proximally from the opener pin 136. The drive actuator shaft 130 is disposed within the plunger 120 and includes a proximal end 132 adjacent the plunger proximal end 122 and a distal end 134 located immediately adjacent the canister 140. For example, the distal end 134 can include a concave or other shape similar to the first end of the canister body 142 such that in the initial position, the distal end 134 abuts the canister body 142.

[0037] The device 160 includes an actuation button 160 coupled to the proximal end 132 of the drive actuator shaft 130, which when pressed, e.g., pushed distally, releases the shaft 130, whereupon the distal end 134 advances distally to move the canister 140 distally until the opener pin 136 opens the septum 144a. The piston 128 may include one or more passages, e.g., passage 128a, therethrough to direct gas released from the canister 140 into the gas chamber 116. Once the chamber 116 is filled, the plunger 120 and internal components, i.e., shaft 130 and canister 140, may be retracted proximally, similar to device 8, until the chamber 116 is filled. The plunger 120 may then be advanced, e.g., by pushing against a thumb rest or other feature 123a on the proximal end 122, thereby directing gas from the chamber 116 into the patient's body via the outlet 115.

[0038] Optionally, any of the devices herein may include a locking mechanism configured to engage and lock the plunger from moving in a proximal direction once the gas chamber is filled with the premixed gas. For example, as shown in FIGS. 4A and 4B, the plunger 120 may be provided with a ratchet mechanism that remains passive as the plunger 120 moves in a proximal direction (during filling) and engages when the plunger 120 is guided to a proximal position, thereby locking the plunger 120 relative to the barrel 110 once the gas chamber 116 is filled. For example, the plunger 120 may include a number of ratchets or engagement elements 127 extending axially along a portion of the plunger 120, e.g., on a rack formed or attached to an outer surface of the plunger 120. A pawl member 154 including one or more ratchets or engagement elements 154a that may interact with the elements 127 on the plunger 120 may be mounted within the barrel 110. For example, the pawl member 154 can be spaced from the plunger 120, as shown, for example, in FIG. 4A, allowing the plunger 120 to freely retract while the gas chamber 116 is filling. Once the chamber 116 is filled, the pawl member 154 can be engaged, thereby preventing the elements 127, 154a from further proximal movement of the plunger 120. Thus, the ratchet mechanism can prevent the plunger 120 from being pulled proximally after the initial actuation (and after degassing and filling of the chamber 116), thereby preventing a user from altering the delivery, which could affect the mix of premixed gas delivered from the gas chamber 116.

[0039] 5A-5C show details of an alternative device 8', which is generally similar to device 8, but includes a pawl member 54' and a ratchet 27', which can operate similarly to the ratchet mechanism shown in FIGS. 4A and 4B. As shown in FIG. 5A, the pawl member 54' can be pivotally mounted to the barrel 10', and the ratchet 27' can be provided on the plunger 20'. The pawl member 54' is initially held in an inactivated position with teeth 54a' spaced apart from teeth 27a' of the ratchet 27'. When the actuation button 60 is actuated, the plunger 20' retracts as gas is released from the canister 60, and when gas is charged, the pawl member 54' is released. The pawl member 54' is biased, for example by a spring or other resilient member 54b', to pivot inwardly to engage the teeth 54a', 27a', as shown in FIG. 5B. Teeth 54a', 27a' may include blunt proximal edges to prevent further movement of plunger 20' in the proximal direction. Additionally, teeth 54a', 27a' may include tapered distal edges such that pawl member 54' may slide over ratchet 27' as plunger 20' advances while gas is being delivered from device 8'. Thus, pawl 54' and ratchet 27' may prevent removal of plunger 20' without impeding delivery of gas to fill gas chamber 16'.

[0040] The devices and systems herein can be used to deliver premixed gases into a patient's body, for example, to the interior of a patient's eye during vitreous surgery, similar to the methods disclosed in U.S. Pat. No. 8,986,242, the entire disclosure of which is expressly incorporated herein by reference.

[0041] While the invention is susceptible to various modifications and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail, It is to be understood, however, that the invention is not limited to the specific forms or methods disclosed, but rather, the invention is intended to cover all modifications, equivalents, and alternatives falling within the scope of the appended claims.

Claims

1. A system for delivering gas, comprising: a barrel including a proximal end, a closed distal end including an outlet, a longitudinal axis extending between the proximal end and the distal end, and a gas chamber in communication with the outlet; a plunger slidably received within a syringe body, the plunger including a piston within the barrel adjacent the distal end and a handle extending from the proximal end of the syringe body; a cannister for containing gas within the plunger, adjacent a through-passage of the piston in communication with the gas chamber, the cannister having a partition adjacent an opener pin; a drive actuator including a first end adjacent the handle and a second end within the plunger adjacent the cannister, the drive actuator being movable to move the second end in a distal direction to release gas from the cannister to the opener pin, whereby gas moves through a passage into the gas chamber, thereby displacing the piston proximally along the axis to fill the gas chamber with gas.

2. The system of claim 1, further comprising a locking mechanism configured to engage the plunger when the gas chamber is filled with gas.

3. The system of claim 2, wherein the gas is a premixed gas, the locking mechanism includes a spring and a rack, and the rack is configured to prevent proximal movement of the plunger so as not to affect the ratio of the premixed gas during introduction of the premixed gas when the gas chamber is filled with the premixed gas.

4. A system for delivering gas, comprising: a barrel including a proximal end, a closed distal end including an outlet, and a gas chamber in communication with the outlet; a plunger slidably received within the barrel, the plunger including a piston within the barrel adjacent the distal end; a gas-filled cannister; a handle on the proximal end of the syringe body; and a drive actuator. ​ ​ The drive actuator is configured to operate to open the partition wall of the gas canister with an opener pin to release gas from the canister, and at that time, gas enters the gas chamber through the piston, thereby displacing the piston in the proximal direction to fill the gas chamber with gas. A system, characterized in that after introducing the tip of a cannula or a needle communicating with the outlet into a patient's body, the plunger is configured to advance to send the gas in the gas chamber into the patient's body through the outlet. Claim 5 A system for delivering gas into a patient's body, comprising a barrel including a proximal end, a closed distal end including an outlet, and a gas chamber communicating with the outlet, a plunger slidably received in the barrel including a piston in the barrel adjacent to the distal end, a gas-filled gas canister, a handle extending from the proximal end of the syringe body, and a drive actuator. The drive actuator is configured to operate to open the partition wall of the gas canister with an opener pin to release gas from the canister, and at that time, gas enters the gas chamber through the piston, thereby displacing the piston in the proximal direction to fill the gas chamber with gas. A system, characterized in that after introducing the tip of a cannula or a needle communicating with the outlet into a patient's body, the plunger is movable forward to send the gas in the gas chamber into the patient's body through the outlet. Claim 6 In the system according to any one of claims 1 to 5, further comprising a cannula or a needle, characterized in that the cannula or the needle is connectable to the distal end of the barrel so as to communicate with the outlet. Claim 7 In the system according to any one of claims 1 to 5, a system, characterized in that the cannula or the needle is permanently attached to the distal end of the barrel. Claim 8 In the system according to claim 7, a system, characterized in that the tip is configured to be introduced into the interior of a patient's eye. Claim 9 In the system according to any one of claims 1 to 5, a system, characterized in that when the gas chamber is filled with gas, the plunger is locked so as not to move in the proximal direction.

10. In the system according to any one of Claims 1 to 5, the system is characterized in that the barrel is provided with a filter adjacent to the outlet for filtering the gas exiting the gas chamber through the outlet.

11. In the system according to Claim 10, the system is characterized in that the filter has a pore size for filtering bacteria such that the gas is considered to be sterile.

12. In the system according to Claim 10, the system is characterized in that the filter has a pore size of about 0.22 μm or less.

13. In the system according to any one of Claims 1 to 5, the drive actuator includes an operating button extending from the handle of the plunger, and this button is operable to move the drive actuator in the distal direction to displace one of the cannister and the opener pin, thereby causing the partition wall to be opened in the opener pin.

14. In the system according to Claim 13, the system is characterized in that the operating button can move in a direction transverse to the longitudinal axis.

15. In the system according to Claim 14, the drive actuator is locked in the proximal position by the operating button, and the drive actuator is released by the movement of the operating button, whereby the drive actuator is biased toward the distal position so as to automatically move toward the distal position to release gas from the cannister.

16. In the system according to any one of Claims 1 to 5, the system is characterized in that the cannister is received in the cavity of the plunger such that the partition wall faces the proximal direction, and the opener is disposed proximal to and spaced from the partition wall in the initial position.

17. In the system according to Claim 16, the system is characterized in that when the operating button is actuated, the drive actuator advances in the distal direction to guide the opener pin in the distal direction to open the partition wall.

18. In the system according to any one of Claims 1 to 5, The system is characterized in that the canister is received within the cavity of the plunger such that the partition wall faces in the distal direction, and the opener is disposed spaced apart from the partition wall on the distal side of the partition wall in the initial position.

19. In the system according to claim 18, when the activation button is actuated, the drive actuator advances in the distal direction to guide the canister in the distal direction to cause the partition wall to open the opener pin. The system is characterized by this.

20. In the system according to any one of claims 1 to 5, the gas is a premixed gas. The system is characterized by this.

21. In the system according to claim 20, the premixed gas contains one of sulfur hexafluoride (SF6) or octafluoropropane (C3F8). The system is characterized by this.

22. In the system according to claim 20, the premixed gas contains about 20 percent (20%) sulfur hexafluoride (SF6). The system is characterized by this.

23. In the system according to claim 20, the premixed gas contains about 14 percent (14%) octafluoropropane (C3F8). The system is characterized by this.

24. In the system according to any one of claims 1 to 5, when the partition wall is opened, as the gas chamber is filled with gas, the gas is supplied under pressure such that the gas expels the residual air in the gas chamber from the outlet. The system is characterized by this.

25. In the system according to claim 24, the gas canister is configured to fill the gas chamber with a preset amount of gas. The system is characterized by this.

Images