Systems and methods for microdose injection

Abstract

To provide a system and a method related to a syringe for delivering fluid of a dose in a microliter range in a medical site.SOLUTION: An injection system 400 includes: a syringe body 410 having a proximal end and a distal end; a syringe inside; and a syringe flange provided in the proximal end. The system 400 further includes injection fluid arranged in the inside of the syringe inside. The system 400 further includes a stopper member 420 arranged in the inside of the syringe inside, and includes a plunger member 450 connected to the stopper member 420. The system 400 further includes a finger flange 440 detachably connected to the syringe flange, and the finger flange 440 includes a screw facing in a proximal direction. The system 400 includes a rotation member arranged on the screw facing in the proximal direction. The rotation member defines a rotation member opening in which the plunger member 450 is arranged, and includes an elastic latch arranged adjacently to the rotation member opening.SELECTED DRAWING: Figure 21

Description

Technical Field

[0001] The present invention generally relates to injection systems, devices, and processes that facilitate the control of various levels of fluid injection, and more particularly to systems and methods related to syringes for delivering micro-liter range doses of fluid in a medical setting.

Background Art

[0002] In a medical setting, millions of syringes such as the syringe 2 shown in 2 of FIG. 1A are consumed daily. A typical syringe 2 includes a tubular body 4, a plunger 6, and an injection needle 8. As shown in FIG. 1B, such a syringe 2 can be used not only to inject fluid into a patient, but also to withdraw or discharge fluid from or into a container such as a vial, ampule, bag, or other drug storage system 10. In fact, in some countries such as the United States, due to regulatory constraints and concerns about maintaining sterility, when using a vial 10 with a syringe 2 as shown in the figure in a specific patient environment, such a vial can only be used by one patient and then must be discarded, which generates a large amount of medical waste from the disposal of vials and remaining drugs, and even causes periodic shortages of certain important pharmaceuticals.

[0003] Referring to Figure 2A, three Luer syringes 12 are shown, each having a distally positioned Luer fitting shape 14, which can be connected to other devices having similar connection shapes, such as the Luer manifold assembly 16 shown in Figure 2B. The Luer manifold assembly in Figure 2B can be used to intravenously administer liquid medication to a patient, with or without using an intravenous infusion bag. The Luer fittings 14 on the syringes in Figure 2A are sometimes called "male" Luer fittings, and those 18 in Figure 2B are sometimes called "female" Luer fittings, with one Luer interface being threaded (in this case, the configuration is called a "Luer lock" configuration), and the two sides can be connected by relative rotation, which may be combined with compressive load. In other words, in one embodiment of a Luer lock, by utilizing rotation, sometimes together with compression, the threads in the male fitting 14, which is configured to engage with the flange of the female fitting 18, can be engaged, allowing the devices to be fluid-sealed and connected. In other embodiments, a tapered interface shape can be used to provide a Luer engagement using compression without threading or rotation (such configurations are sometimes called “slip-on” or “conical” Luer configurations). While such Luer connections are perceived as relatively safe for operators, there is a risk of drug spillage, leakage, or parts breakage during filling to provide the Luer connection. On the other hand, when using injection needles, there is an undesirable risk of the sharp needle coming into contact with or piercing people or structures. For this reason, so-called “safety syringes” have been developed.

[0004] One embodiment of the safety syringe 20 is shown in Figure 3, in which a tubular shield member 22 is spring-biased to cover the needle 8 when released from the locked position relative to the syringe body 4. Another embodiment of the safety syringe 24 is shown in Figures 4A-4B. In this configuration, after the plunger 6 is fully inserted into the syringe body 4, the retractable needle 26 is configured to retract 28, 26 to a safe position within the tubular body 4, as shown in Figure 4B. Such a self-retracting configuration comes with problems such as blood splattering and aerosol generation, the safe storage of pre-loaded energy which may be activated by malfunction before reaching the desired state, reduced accuracy when performing full-volume injection due to dead space remaining in the compressed volume of the spring, and / or loss of control over the retraction speed which may lead to pain and patient discomfort.

[0005] Further complicating the syringe market is the increasing demand for drug-filled syringe assemblies, as shown in Figures 5A and 5B, which generally include a syringe body or "drug-sealed delivery system" 34, a plunger tip, plug, or stopper 36, and a distal seal or cap 35 that can be mounted on a Luer interface (Figure 5A shows the cap 35 in place, and Figure 5B shows the cap removed to illustrate the Luer interface 14). The drug solution may reside in the volume between the distal seal 35 and the distal end 37 of the stopper member 36, i.e., the drug reservoir 40. 6 may include a standard butyl rubber material and a biocompatible lubricating coating (for example, polytetrafluoroethylene ("PTFE"), which enhances the desirable sealing and relative movement characteristics of the corresponding syringe body 34. The proximal end of the syringe body 34 in Figure 5B includes a conventional one-piece syringe flange 38 formed integrally with the material of the syringe body 34. The flange 38 is configured to extend radially from the syringe body 34 and may be configured to be a full or partial circumference around the syringe body 34. A partial flange is called a "clip flange," and the other is This is called a "full flange." The flange provides support when gripping the syringe with your fingers and pushing the plunger to inject. The syringe body 34 preferably contains a translucent material such as glass or polymer. A stopper member 36 may be positioned within the syringe body 34 to form a volume to be contained within the drug chamber or reservoir 40 and to assist in the discharge of the associated fluid through the needle. The syringe body may be defined as substantially cylindrical in shape (i.e., so that the plunger tip 36 having a circular cross-sectional shape establishes a seal with the syringe body), or it may be configured to have other cross-sectional shapes such as elliptical.

[0006] Such assemblies are needed because there are few manufacturers in the world that can afford to meet all of the ever-changing global regulations regarding filling, packaging, selection of pharmaceutical / drug interface materials, and component use, and that can standardize and mass-produce them with high precision. However, such simple configurations cannot meet new global standards such as single-use, safety, auto-deactivation, and needle-stick prevention. Therefore, some suppliers are moving towards more "vertical" solutions, such as 41 shown in Figure 5C, which attempt to meet all or at least some of the standards in a single solution. However, such products have considerable limitations (including some of the limitations mentioned above, see Figures 3-4B) as they try to meet these standards in many different scenarios, and can incur relatively high inventory and utilization costs.

[0007] Furthermore, the accuracy and precision of injection systems decrease when the volume of injected fluid reaches the microliter range ("microdoses"). In particular, with microdose injection systems, it is difficult to accurately remove air from the syringe body (defoaming) before injection.

[0008] An injection system is needed that addresses the shortcomings of currently available configurations. In particular, an injection system that operates precisely (defoaming and injecting) in microliter units is required. Furthermore, it is desirable that such syringe assemblies can utilize the existing, relatively well-managed supply chain of conventionally available pre-filled cartridges and other off-the-shelf components, as well as the corresponding assembly machines and personnel. [Overview of the project]

[0009] The embodiments relate to injection systems. In particular, the embodiments relate to microliter-range injection systems including at least several off-the-shelf syringe components.

[0010] In one embodiment, the injection system includes a syringe body having a proximal and distal end, the interior of the syringe, and a syringe flange provided at the proximal end. The system also includes an injection fluid disposed within the interior of the syringe. The system further includes a stopper member disposed within the interior of the syringe. Furthermore, the system includes a plunger member connected to the stopper member. The system further includes a finger flange detachably connected to the syringe flange, the finger flange including a proximal-facing thread. The system also includes a rotating member disposed on the proximal-facing thread, the rotating member defining a rotating member opening through which the plunger member is placed, and having an elastic latch disposed adjacent to the rotating member opening. The rotating member is configured to insert the plunger member and the stopper member connected thereto distally into the interior of the syringe relative to the syringe body by rotation of the rotating member relative to the proximal-facing thread. The elastic latch is configured to allow the plunger member to be inserted distally from the rotating member opening while preventing the plunger member from being removed proximal to the rotating member opening.

[0011] In one or more embodiments, the syringe body also includes a distal needle interface configured to connect to a needle assembly having a needle. When the rotating member is rotated, the plunger member and the stopper member are inserted, thereby priming the needle for injection with a portion of the injection fluid from inside the syringe passing through the needle.

[0012] In one or more embodiments, the plunger member includes a thumb pad at its proximal end, and the system also includes a plunger cap that is detachably connected to the rotating member and configured to prevent the user from contacting the thumb pad. The rotating member may have a sloping trough and a circumferential trough defined on its outer surface, and the plunger cap may include a tongue facing inward toward the longitudinal axis of the plunger cap. If the tongue is positioned in the circumferential trough, interference between the tongue and the circumferential trough can prevent the plunger cap from moving proximal to the rotating member. The rotating member may also include a bump positioned between the sloping trough and the circumferential trough on its outer surface. The bump of the rotating member and the tongue of the plunger cap may be configured to prevent the plunger cap from disengaging from the rotating member until a predetermined amount of torque is applied to the plunger cap relative to the rotating member. A predetermined amount of torque can be selected such that the plunger cap disengages from the rotating member only after the rotating member reaches the distal end of the proximal-facing screw on the finger flange, thereby allowing the needle to be primed for injection by a portion of the injection fluid from inside the syringe passing through the needle.

[0013] In one or more embodiments, the plunger cap defines a proximal opening large enough for the plunger member to pass through. The plunger member may include a flange configured to interfere with an elastic latch to restrict the proximal movement of the plunger member relative to the rotating member. The rotating member may include a threaded end at its distal end, and the finger flange may include a latch positioned on the proximal-facing thread, configured to interfere with the threaded end to restrict the rotation and proximal movement of the rotatable member relative to the finger flange.

[0014] In other embodiments, a method for assembling an injection system includes connecting a rotating member to a finger flange to form a finger flange / rotating member unit. The method also includes connecting a plunger cap to a rotating member to form a finger flange / rotating member / plunger cap unit. The method further includes mounting the finger flange / rotating member / plunger cap unit onto a filled syringe. The filled syringe includes a syringe body defining the inside of the syringe, an injection fluid disposed inside the syringe, and a stopper member disposed inside the syringe to hold the injection fluid inside the syringe. Furthermore, the method includes inserting a plunger member into the syringe through the finger flange / rotating member / plunger cap unit. Furthermore, the method includes connecting the plunger member to the stopper member inside the syringe.

[0015] In one or more embodiments, the finger flange includes proximal threads, and the method also includes connecting the rotating member to the finger flange by screwing the rotating member onto the proximal threads on the finger flange to form a finger flange / rotating member unit.

[0016] In one or more embodiments, a plunger cap defines a proximal opening, a rotating member defines a rotating member opening, and a finger flange defines a finger flange opening. The method includes inserting the plunger member into the syringe through the proximal opening, the rotating member opening, and the finger flange opening. The rotating member may have an inclined trough and a circumferential trough defined on its outer surface. The plunger cap may include a tongue oriented inward toward the longitudinal axis of the plunger cap. The method may also include connecting the plunger cap to the rotating member such that the tongue of the plunger cap is positioned in the circumferential trough, and the plunger cap is screwed onto the rotating member to form a finger flange / rotating member / plunger cap unit such that interference between the tongue and the circumferential trough prevents the plunger cap from moving proximal to the rotating member.

[0017] In one or more embodiments, the finger flange includes a side opening, and the syringe body includes a syringe flange. The method includes mounting the finger flange / rotating member / plunger cap unit onto the syringe body by inserting the syringe flange of the syringe body into the side opening of the finger flange. The stopper member may include a threaded stopper member recess, and the plunger member may include a distal threaded member. The method also includes connecting the plunger member to the stopper member inside the syringe by screwing the distal threaded member of the plunger member into the threaded stopper member recess of the stopper member.

[0018] In yet another embodiment, the method of injecting a fluid includes preparing a syringe assembly. The syringe assembly includes a syringe body having a proximal end and a distal end, the interior of the syringe, a distal needle interface provided at the distal end, and a syringe flange provided at the proximal end. The syringe assembly also includes the fluid to be injected, disposed within the syringe interior. The syringe assembly further includes a stopper member disposed within the syringe interior. Furthermore, the syringe assembly includes a plunger member connected to the stopper member. In addition, the syringe assembly includes a finger flange detachably connected to the syringe flange, the finger flange including a proximal-facing thread. The syringe assembly also includes a rotating member disposed on the proximal-facing thread. The syringe assembly further includes a plunger cap detachably connected to the rotating member. Furthermore, the syringe assembly includes a needle assembly having a needle connected to the distal needle interface of the syringe body. The method also includes priming the needle for injection with a portion of the injection fluid from inside the syringe through the needle by rotating the plunger cap relative to a proximal-facing screw and rotating the rotating member relative to a proximal-facing screw. The method further includes removing the plunger cap from the rotating member, thereby exposing the proximal end of the plunger member. Furthermore, the method includes applying a distal force to the proximal end of the plunger member to expel the remaining portion of the injection fluid from inside the syringe through the needle.

[0019] In one or more embodiments, the rotating member includes an inclined trough and a circumferential trough defined on its outer surface, and a bump positioned between the inclined trough and the circumferential trough on its outer surface. The plunger cap may include a tongue oriented inward toward the longitudinal axis of the plunger cap. When the tongue is positioned in the circumferential trough, interference between the tongue and the circumferential trough can prevent the plunger cap from moving proximal to the rotating member. The bump of the rotating member and the tongue of the plunger cap may be configured to prevent the plunger cap from disengaging from the rotating member until a predetermined amount of torque is applied to the plunger cap with respect to the rotating member. Removing the plunger cap from the rotating member may include applying a predetermined amount of torque to the plunger cap with respect to the rotating member after the rotating member has reached the distal end of the thread facing proximal to the finger flange.

[0020] The above-mentioned and other embodiments of the present invention are described in the detailed description below. [Brief explanation of the drawing]

[0021] The aforementioned and other embodiments of the embodiment will be described in further detail with reference to the accompanying drawings, in which the same elements in different figures are referred to by common reference numerals.

[0022] [Figure 1] Figures 1A-B show the configuration of a conventional injection syringe. [Figure 2] Figures 2A-B show the configuration of a conventional injection syringe. [Figure 3] Figure 3 shows a configuration of a conventional injection syringe. [Figure 4] Figures 4A-B show the configuration of a conventional injection syringe. [Figure 5] Figures 5A-C show the configuration of a conventional injection syringe. [Figure 6] Figure 6 shows an embodiment of a microdose injection system and a microdose injection method according to some embodiments. [Figure 7] Figure 7 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 8] Figure 8 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 9] Figure 9 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 10] Figure 10 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 11] Figure 11 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 12] Figure 12 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 13] Figure 13 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 14] Figure 14 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 15] Figure 15 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 16] Figure 16 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 17] Figure 17 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 18] Figure 18 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 19] Figure 19 shows aspects of a microdose injection system and a microdose injection method according to some embodiments. [Figure 20]Figure 20 shows an embodiment of a microdose injection system and a microdose injection method according to some embodiments. [Figure 21] Figure 21 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to some embodiments. [Figure 22] Figure 22 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to some embodiments. [Figure 23] Figure 23 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to some embodiments. [Figure 24] Figure 24 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to some embodiments. [Figure 25] Figure 25 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to one of the embodiments. [Figure 26] Figure 26 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to some embodiments. [Figure 27] Figure 27 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to some embodiments. [Figure 28] Figure 28 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to some embodiments. [Figure 29] Figure 29 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to some embodiments. [Figure 30] Figure 30 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to one of the embodiments. [Figure 31]Figure 31 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to some embodiments. [Figure 32] Figure 32 shows an embodiment of a microdose injection stem and microdose injection method equipped with a plunger cap according to one of the embodiments.

[0023] To better understand the above-mentioned and other advantages and objectives of the various embodiments, the embodiments will be described in more detail with reference to the attached drawings. Note that the drawings are not in exact proportions, and elements having similar structure or function are represented by similar reference numbers throughout. Please understand that these drawings illustrate only specific illustrative embodiments and are not intended to limit the scope of the embodiments. [Modes for carrying out the invention]

[0024] Exemplary Microdose Injection System Figures 6-20 show a microdose injection system 300 according to other embodiments. The term “microdose” or “micro-dose” as used herein includes, but is not limited to, injections in the range of 1 to 1,000 microliters. The microdose injection system 300 addresses the problem of injections in the microliter (e.g., 10 μL) volume range, which is difficult to perform with standard injection systems, while maintaining precision (e.g., reproducibility) and accuracy (e.g., approximation to the desired volume). The microdose injection system 300 performs microdose injections using a rotating microdose adapter / rotating member 360 and the travel distance / gap of a fixed plunger member.

[0025] The microdose injection system 300 utilizes a ready-made syringe body 310, stopper member 320, and connecting member 330. The microdose injection system 300 can also use a ready-made needle assembly 390, including a needle 392. The finger flange 340 of the microdose injection system 300 includes a male-threaded proximal section 342 configured to mate with a microdose adapter / rotating member 360 having a corresponding female thread, as shown in Figures 11, 14, 17, and 20.

[0026] The microdose injection system 300 includes a syringe body 310, a stopper member 320, a connecting member 330, a finger flange 340, a plunger member 350, a needle assembly 390, and a microdose adapter / rotating member 360. Many of these system components (e.g., the syringe body 310, the stopper member 320, and the connecting member 330) may be off-the-shelf components to utilize existing, relatively well-managed supply chains and corresponding assembly machines and personnel. The syringe body 310 may be an off-the-shelf 0.50cc syringe body 310 to improve the precision of the microdose injection system 300. The needle assembly 390 may be a commercially available off-the-shelf needle assembly with a needle 392 (e.g., 20-34 gauge, 6mm-5 / 8 inch in length, particularly 32 gauge × 6mm in length). The needle assembly 390 may utilize a Luer lock configuration or a Luer slip configuration for attaching the needle assembly 390 to the syringe body 310 / connecting member 330. In some embodiments, the microdose injection system 300 can achieve an error rate of less than ±10 μL.

[0027] The microdose adapter / rotating member 360 includes a flange 362 configured to exert a small distal force on a shoulder / internal stop 352 formed on the plunger member 350 when the microdose adapter / rotating member 360 is rotated clockwise on the male threaded proximal section 342 of the finger flange 340. Rotating the microdose adapter / rotating member 360 with the microdose injection system 300 oriented vertically can remove bubbles from the injectable substance inside the syringe interior 312 and / or the needle assembly 390 / needle 392 ("defoaming" or "degassing").

[0028] Furthermore, the plunger member 350 includes a constricted portion 354 configured to pass through the opening 364 of the microdose adapter / rotating member 360, which is surrounded / expanded to form a shoulder / internal stop 352. By changing the length of the constricted portion 354, the injection volume and travel distance / gap can be controlled.

[0029] Furthermore, the microdose injection system 300 shown in Figures 6-20 includes a plunger cap 370. The plunger cap 370 is configured to prevent premature injection by preventing distal movement of the plunger member 350, while allowing the microdose adapter / rotating member 360 to rotate to degas the microdose injection system 300. After the plunger cap 370 is removed, the plunger member 350 can move distally, but only by a distance equal to the travel distance / gap, which is equal to the length of the constricted portion 354 outside the microdose adapter / rotating member 360. Thus, the injection volume is controlled by the length of this constricted portion 354. Therefore, the microdose injection system 300, along with a precise degassing mechanism, enables precise and accurate injection.

[0030] Figures 6-20 illustrate the injection process using the microdose injection system 300. Figures 6-8 show the microdose injection system 300 before it is connected to the needle using the connecting member 330. In this state, the connecting member 330 is covered by the connecting member cover.

[0031] Figures 9-11 show the microdose injection system 300 after the needle has been connected to the microdose injection system 300 using the connecting member 330. In this embodiment, the connecting member 330 is a female Luer connector, and the corresponding connecting member on the needle is a male Luer connector, so a Luer lock connection is formed as shown in Figure 10.

[0032] Figures 9-11 show the microdose injection system 300 in a vertical position, with the needle generally facing upward. Therefore, as shown by the gas / air bubbles 302 in Figure 10, all the gas / air within the syringe body 310 moves to the top of the syringe body 310. At this position, distal movement of the stopper member 320 expels the gas / air bubbles 302 from the syringe body 310 and / or air from inside the needle assembly 390 / needle 392, preparing the microdose injection system 300 for injection. The process of expelling the gas / air bubbles 302 from the syringe body 310 and / or air from inside the needle assembly 390 / needle 392 is also called degassing or priming the injection system 300. Additionally, during the priming process of the injection system, some of the injection fluid may be expelled from the syringe or needle.

[0033] Figure 11 shows in detail the relative positions of the microdose adapter / rotating member 360, the threaded proximal section 342 of the finger flange 340, and the plunger cap 370, showing the microdose injection system 300 in the vertical position, i.e., the "defoamed" position. The threads of the threaded proximal section 342 of the finger flange 340 are omitted for clarity in the figure.

[0034] Figures 12-14 show the microdose injection system 300 after degassing. The degassing process involves rotation of the microdose adapter / rotating member 360 in the direction (for example, clockwise for a typical screw part) when the microdose injection system 300 is in the vertical degassing position.

[0035] The plunger cap 370 has a plurality of inward-facing splines, and the microdose adapter / rotating member 360 has a corresponding plurality of outward-facing splines. The inward and outward splines are configured such that when the plunger cap 370 is removably connected to the plunger microdose adapter / rotating member 360, the rotation of the plunger cap 370 causes the corresponding rotation of the microdose adapter / rotating member 360.

[0036] The clockwise rotation of the microdose adapter / rotating member 360 moves it distally on the threaded proximal section 342 of the finger flange 340, thereby advancing the plunger member 350 and the stopper member 320 connected to it distally within the syringe body 310. As the microdose adapter / rotating member 360 moves distally relative to the syringe body 310, as shown in Figure 14, the distally facing surface 361 on the adapter 360 exerts a distal force on the proximal facing surface 353 on the shoulder / internal stop 352 connected to or formed at the proximal end of the plunger member 350. The distal force is proportional to the amount of rotation of the microdose adapter / rotating member 360 and is transmitted to the stopper member 320 via the plunger member 350.

[0037] A distal force causes the stopper member 320 to move distally within the syringe body 310. Since the microdose injection system 300 is in a vertical degassing position, the distal movement of the stopper member 320 within the syringe body 310 causes gas / air bubbles (see 302 in Figure 10) to be expelled from the syringe body 310 and / or air to be expelled from the needle assembly 390 / needle 392, thereby degassing or priming the microdose injection system 300.

[0038] Figures 15-17 show the next step in the injection process, the removal of the plunger cap 370. By applying sufficient proximal force to the plunger cap 370, the plunger cap 370 can overcome the elasticity of the retaining member in the embodiments shown in Figures 6-20 and move proximal to the microdose adapter / rotating member 360. The removal of the plunger cap 370 allows the thumb pad / external stop 356 and the plunger member 350 to move distally, thereby placing the microdose injection system 300 ready for injection.

[0039] As shown in Figure 17, the microdose adapter / rotating member 360 includes a proximal flange 362. The narrow portion 354 of the plunger member 350 defines a gap 358 between the proximal-facing surface of the proximal flange 362 and the distal-facing surface of the thumb pad / external stop 356. The size of the gap 358 can be changed by modifying the plunger member 350 and / or the thumb pad / external stop 356. The size / axial length of the gap 358 determines the amount of axial movement of the stopper member 320 inside the syringe body 310, and therefore determines the amount of fluid (e.g., drug) injected by the microdose injection system 300.

[0040] Furthermore, referring to Figure 17, the plunger member 350 also includes a shoulder / internal stop 352. Both the shoulder / internal stop 352 and the thumb pad / external stop 356 are sized so that they cannot pass through the opening of the microdose adapter / rotating member 360. Therefore, the relative positions of the shoulder / internal stop 352 and the thumb pad / external stop 356 define the maximum amount of movement of the plunger member 350 relative to the microdose adapter / rotating member 360. This maximum amount of movement of the plunger member 350 also corresponds to the size / axial length of the gap 358. In addition, the shoulder / internal stop 352 prevents the plunger member 350 from being removed from the microdose adapter / rotating member 360.

[0041] Figures 18-20 illustrate the next step in the injection process, microdose injection. A distal force is applied to the thumb pad / external stop 356, thereby advancing the plunger member 350 and the stopper member 320 connected to it distally within the syringe body 310. This distal force can be applied manually by the user or automatically by the auto-injector.

[0042] Comparing Figures 17 to 20, it can be seen that when a distal force is applied to the thumb pad / external stop 356, the outer gap 358 (see Figure 17) of the microdose adapter / rotating member 360 disappears. This also moves the shoulder / internal stop 352 distally away from the distal-facing surface 361 of the microdose adapter / rotating member 360. In practice, as shown in Figure 20, an internal gap 358' is formed inside the microdose adapter / rotating member 360. This internal gap 358' has the same size / axial length as the original gap 358 on the outside of the microdose adapter / rotating member 360.

[0043] Comparing Figures 16 and 19, it can be seen that the distal movement of the stopper member 320 inside the syringe body 310 causes some of the fluid to be discharged from inside the syringe body 310, resulting in the injection of a predetermined amount of fluid. In microdose applications, this predetermined amount of fluid can range from approximately 5 μL to approximately 250 μL. In a particular embodiment, this predetermined amount of fluid is approximately 10 μL.

[0044] Exemplary Plunger Cap / Rotating Member Embodiment Figures 21-29 show a microdose injection system 400 according to some embodiments. The microdose injection system 400 is structurally and functionally similar to the system 300 shown in Figures 6-20. However, the microdose injection system 400 includes a finger flange 440, a microdose adapter / rotating member 460, and a plunger cap 470, which differ from the corresponding components 340, 360, and 370 of the system 300 shown in Figures 6-20.

[0045] The microdose injection system 400 includes a syringe body 410, a stopper member 420, a connecting member 430, a finger flange 440, a plunger member 450, a needle assembly 490, a microdose adapter / rotating member 460, and a plunger cap 470. Many of these system components (e.g., the syringe body 410, the stopper member 420, and the connecting member 430) may be off-the-shelf components to take advantage of existing, relatively well-managed supply chains and corresponding assembly machines and personnel. For example, the off-the-shelf stopper member 420 is a commercially available stopper member whose distal surface is generally smooth and does not include any protrusions or recesses for connecting to a needle.

[0046] Similar to the finger flange 340 of system 300 shown in Figures 6-20, the finger flange 440 is detachably connectable to the syringe body 410 and includes a male threaded proximal section 442 configured to mate with a microdose adapter / rotating member 460 having a corresponding female thread. As shown in Figure 29, the male threaded proximal section 442 includes a latch 444 configured to interfere with the end 461 of the female thread on the microdose adapter / rotating member 460, allowing the microdose adapter / rotating member 460 to rotate clockwise on the male threaded proximal section 442 of the finger flange 440, while preventing the microdose adapter / rotating member 460 from rotating counterclockwise beyond the latch 444. Thus, the latch 444 prevents the microdose adapter / rotating member 460 from being detached from the finger flange 440 after it has been connected to the finger flange 440. The adapter / rotating member 460 may include inwardly projecting ribs (not shown) that engage with the latch 444 to provide multiple spaced stopping points on its inner circumference to minimize backlash while preventing counterclockwise rotation. Furthermore, the inwardly projecting ribs may be configured to provide tactile or auditory feedback to the operator.

[0047] As shown in Figures 22, 27, and 28, the microdose adapter / rotating member 460 includes a plurality of elastic latches 462 arranged around a central opening 464 and facing inward toward the longitudinal axis of the microdose adapter / rotating member 460. In the embodiments shown in Figures 21-29, the microdose adapter / rotating member 460 includes elastic latches 462. The elastic latches 462 are configured to interfere with shoulder / internal stop 452 on the plunger member 450, allowing distal insertion of the plunger member 450 through the central opening 464 relative to the microdose adapter / rotating member 460, while preventing the removal of the plunger member 450 from the microdose adapter / rotating member 460 after it has been inserted through the latter.

[0048] The microdose adapter / rotating member 460 also includes a pair of troughs on its outer surface. Each of the pair of troughs includes an inclined / diagonal trough 465, which is proximal to the side at its proximal end to allow components of the plunger cap 470 to enter the inclined / diagonal trough 465. The distal end of the inclined / diagonal trough 465 connects to a circumferential trough 466. The circumferential trough 466 includes a bump 467 and a proximal surface 468 configured to removably connect the plunger cap 470 to the microdose adapter / rotating member 460. The circumferential trough 466 also includes a circumferential surface 469 (together with the bump 467) configured to allow the plunger cap 470 to rotate the microdose adapter / rotating member 460. When the microdose adapter / rotating member 460 is rotated clockwise, the microdose adapter / rotating member 460 moves distally. Due to interference between the elastic latch 462 and the shoulder / internal stop 452 of the plunger member 450, when the microdose adapter / rotating member 460 is moved distally, the plunger member 450 (and the stopper member 420 attached thereto) also moves distally.

[0049] As shown in Figure 28, the plunger cap 470 includes a pair of elastic fingers 472 positioned on its inner circumferential surface. The pair of elastic fingers 472 interfere with a corresponding pair of troughs 465, 466 and bumps 467, thereby configuring the plunger cap 470 to be removably connected to the microdose adapter / rotating member 460. The elastic fingers 472 are also configured to interfere with the circumferential surface 469 and bumps 467 of the corresponding circumferential trough 466, allowing the plunger cap 470 to rotate the microdose adapter / rotating member 460. The interference between the elastic fingers 472 and the bumps 467 allows the plunger cap 470 to rotate the microdose adapter / rotating member 460 clockwise, thereby advancing the plunger member 450 distally. After the microdose adapter / rotating member 460 has rotated clockwise to its limit of movement, if the plunger cap 470 continues to rotate clockwise, the elastic finger 472 moves beyond the bump 467 of the circumferential trough 466 and into the inclined / diagonal trough 465. As the plunger cap 470 continues to rotate clockwise, the elastic finger 472 follows the inclined / diagonal trough 465, pushing the plunger cap 470 out of the adapter / rotating member 460. At this point, the elastic finger 472 disengages from the inclined / diagonal trough 465, thereby freeing the plunger cap 470 from the microdose adapter / rotating member 460.

[0050] The plunger member 450 includes a thumb pad / external stop 456 at its distal end, facilitating the user to apply distal force to the plunger member 450 for microdose injection. The plunger cap 470 also includes an axial window 474 that allows the thumb pad / external stop 456 to be seen through the plunger cap 470, even when it is detachably coupled to the microdose adapter / rotating member 460. The axial window 474 helps prevent a situation where the user mistakes the plunger cap 470 for the thumb pad and applies distal force thereto, by allowing the user to see the thumb pad / external stop 456. While the plunger cap 470 cannot actually push the thumb pad / external stop 456 distally, applying distal force to the plunger cap 470 could damage it. The axial opening 474 is sized and shaped to prevent manual manipulation of the thumb pad / external stop 456 from outside the plunger cap 470. Furthermore, the plunger cap 470 includes a knurled outer surface 476 to facilitate its rotation.

[0051] Figures 22-25 show various steps in assembling a microdose injection system 400 according to some embodiments. In Figure 22, the finger flange 440, the microdose adapter / rotating member 460, and the plunger cap 470 are positioned for assembly. The microdose adapter / rotating member 460 is rotated clockwise on the proximal section 442 of the finger flange 440. The microdose adapter / rotating member 460 is rotated on the finger flange 440 until the latch 444 of the finger flange 440 engages with the microdose adapter / rotating member 460. Next, the plunger cap 470 is rotated counterclockwise on the microdose adapter / rotating member 460 by aligning the pair of elastic fingers 472 with the corresponding pair of inclined / diagonal troughs 465 on the microdose adapter / rotating member 460 via the proximal opening. The plunger cap 470 is rotated on the microdose adapter / rotating member 460 until the elastic finger 472 passes through the bump 467 in the circumferential trough 466, thereby temporarily fixing the plunger cap 470 on the microdose adapter / rotating member 460.

[0052] Figure 23 shows the assembled finger flange 440, microdose adapter / rotating member 460, and plunger cap 470. Figure 24 shows the next step in which the assembled finger flange 440, microdose adapter / rotating member 460, and plunger cap 470 are removably connected to the glass syringe flange of the syringe body 410. The side opening of the finger flange 440 is slid on the syringe flange of the syringe body 410 to removably connect the finger flange 440 to the syringe body 410. The syringe body 410 can be formed from glass, polymer (such as COC, COP, polypropylene, polyester, or other polymer materials), metal, or other suitable material. The syringe body may be configured with a user-removable connecting member cap 432' for later needle attachment, or it may have a pre-attached needle (not shown). Prior to assembling the flange and plunger components, the syringe body 410 may be pre-filled with the drug 412 and then closed with the syringe cap and stopper component 420. The pre-filling of the syringe body 410 is performed using a sterile filling machine. By assembling the finger flange and plunger components after the syringe is pre-filled, it becomes unnecessary to install the mechanism required for attaching the finger flange inside the sterile filling machine, thereby improving the throughput of the filling machine and reducing the cost of the sterile filling machine.

[0053] Figure 25 shows how the plunger member 450 is inserted into the syringe body 410 through the proximal opening 474 of the plunger cover 470, the central opening 464 of the microdose adapter / rotating member 460, and the finger flange 440. The plunger member 450 is inserted until its shoulder / internal stop 452 moves distally beyond the elastic latch 462 of the microdose adapter / rotating member 460, thereby preventing the plunger member 450 from being pulled proximal out of the microdose adapter / rotating member 460.

[0054] After the plunger member 450 is inserted into the syringe body 410, the distal end of the plunger member 450 is connected to the stopper member 420 (for example, by rotating the plunger member 450 on the stopper member 420 via the proximal opening 474 of the plunger cap 470). By connecting the plunger member 450 to the stopper member 420, the assembly process is completed, resulting in a ready-to-use microdose injection system 400, as shown in Figure 21. The connection of the plunger member 450 to the stopper member 420 may occur simultaneously with the insertion of the shoulder 452 beyond the elastic latch 462. Alternatively, the connection of the plunger member 450 may occur before or after the insertion of the shoulder 452 beyond the elastic latch 462. In other embodiments, the end of the plunger member 450 is not threaded. Instead, it is provided with a bump that fits into a socket on the stopper member 420. In yet another embodiment, the end of the plunger member 450 is provided with a pin that maintains alignment while engaged with the stopper member 420.

[0055] Figure 26 shows an intermediate step in the assembly of a microdose injection system 400 according to one of the alternative embodiments. In this embodiment, the microdose adapter / rotating member 460 is rotated on a finger flange 440, which is removably connected to a syringe flange on the syringe body 410. The plunger member 450 is then inserted into the syringe body 410 through the central opening 464 of the microdose adapter / rotating member 460 and the finger flange 440. The distal end of the plunger member 450 is then connected to a stopper member 420 (for example, by rotating the plunger member 450 on the stopper member 420). Finally, the plunger cap 470 is rotated on the microdose adapter / rotating member 460 to complete the assembly of the microdose injection system 400. The plunger member 450 may be inserted into the adapter / rotating member 460 with the plunger cap 470 positioned in the predetermined location on the adapter / rotating member 460, or before the plunger cap 470 is assembled to the adapter / rotating member 460. Figure 27 shows the insertion of the plunger member 450 into the central opening 464 of the microdose adapter / rotating member 460.

[0056] Figures 30 to 32 show a microdose injection system 400' according to some embodiments. The microdose injection system 400' is structurally and functionally similar to the microdose injection system 400 shown in Figures 21 to 29. For example, the microdose injection system 400' shown in Figure 30 includes a syringe body 410, a stopper member 420, a finger flange 440, a plunger member 450, and a microdose adapter / rotating member 460'. The system 400' also includes a connecting member, a needle assembly, a removable connecting member cap, and a plunger cap, as shown and described above in Figures 21 to 29. However, these elements are omitted for clarity in the figures.

[0057] One difference between the microdose injection systems 400 and 400' shown in Figures 21-29 and 30-32 is the number of elastic latches 426 and 426'. The microdose injection system 400 shown in Figures 21-29 has four elastic latches 426, while the microdose injection system 400' shown in Figures 30-32 has six elastic latches 426' (see Figure 32).

[0058] Another difference between the microdose injection systems 400 and 400' shown in Figures 21-29 and 30-32 is the shape of the proximal flange 463 located at the proximal end of the microdose adapter / rotating member 460'. The microdose injection system 400 shown in Figures 21-29 has an inclined flange (see Figure 28), while the microdose adapter / rotating member 460' shown in Figures 30-32 has a vertical flange 463 (see Figures 31 and 32). The flange 463 on the microdose adapter / rotating member 460' interferes with the external stop 458 on the distal surface of the thumb pad 456, limiting the distal movement of the plunger member 450 and defining the size of the injection dose. This interference is achieved by elastic finger-style latches 462', as shown in Figures 30-32, but can also be achieved by other mechanical interference mechanisms such as ratchets / pawls, snap-fits, press-fits, clutches, and toothless friction ratchets.

[0059] Although various embodiments using specific connectors (such as slip or luer connectors) have been described above, these embodiments can use any known connector of injection system. Although various embodiments using stake needles and needle connectors have been described, these embodiments can use any known permanently connected needle or needle connector system.

[0060] Various exemplary embodiments of the present invention are described herein. These examples are described in a non-limiting manner. They are provided to illustrate broader applicable aspects of the present invention. Various modifications can be made to the described inventions and replaced with equivalents without departing from the true spirit and scope of the present invention. Furthermore, numerous modifications can be made to adapt specific situations, materials, composition of substances, processes, process procedures, or steps to the object, spirit, or scope of the present invention. Furthermore, those skilled in the art will understand that the individual configurations described and illustrated herein have individual components and features that can be readily separated from or combined with features of any of several other embodiments without departing from the scope or spirit of the present invention. All such modifications are intended to be within the scope of the claims relating to this disclosure.

[0061] Any device described for performing the diagnostic or interventional procedure in question is available as a packaged combination for performing such intervention. These supply “kits” include instructions for use and are packaged in sterile trays or containers commonly used for such purposes.

[0062] The present invention includes methods that can be carried out using the subject device. The methods may include the act of preparing such a suitable device. Such preparation can be performed by an end user. That is, the act of “preparing” simply means that the end user prepares the device required in the subject method by obtaining, accessing, approaching, arranging, setting up, starting, powering on, etc. The methods described herein can be carried out in any logically possible order, not just the order of events described.

[0063] Exemplary embodiments of the present invention have been described, along with details of material selection and manufacturing. Other details of the present invention are understandable from the aforementioned patents and published documents, and are also widely known or understandable to those skilled in the art. For example, those skilled in the art will understand that applying one or more lubricating coatings (e.g., hydrophilic polymers such as polyvinylpyrrolidone compositions, fluoropolymers such as tetrafluoroethylene, PTFE, hydrophilic gels, silicones, etc.) to various parts of a device, such as relatively large interfaces of movably connected parts, can facilitate, for example, low-friction operation or advancement of such objects against other parts of the instrument or adjacent tissue structures. The same is true with respect to method-based embodiments of the present invention in terms of additional actions that are generally or logically performed.

[0064] Furthermore, while the present invention has been described with reference to several examples incorporating various features as options, the present invention is not limited to the features described or shown in each carefully considered modification of the present invention. Various modifications can be made to the described invention without departing from the true spirit and scope of the invention, and substitutions can be made with equivalents (whether described herein or not, for the sake of brevity). Furthermore, where a range of values ​​is presented, it is understood that all intermediate values ​​between the upper and lower limits of that range, and other presented values ​​or intermediate values ​​within that presented range, are included in the present invention.

[0065] Furthermore, any inventive feature described herein is considered claimable, either independently or in combination with any one or more features described herein. A singular item includes the possibility of multiple identical items. More specifically, as used herein and in related claims, the singular forms “a,” “an,” and “said and the” include multiple subjects unless otherwise specified. In other words, the use of articles leaves room for “at least one” subject matter, not only in the claims relating to this disclosure but also in the above description. It should be noted that such claims can be drafted to exclude any optional elements. In this regard, this statement is intended to provide a basis for the use of exclusive terms such as “single,” “only,” or “negative” limitations in the description of claim elements.

[0066] If such exclusive terms are not used, the term “comprising” in the claims relating to this disclosure shall allow the inclusion of any additional elements, regardless of whether a predetermined number of elements are enumerated in such claims, or whether the addition of features is deemed to alter the nature of the elements described in such claims. Unless expressly defined herein, all technical and scientific terms used herein shall be used in the broadest possible sense as commonly understood, while maintaining the validity of the claims.

[0067] The scope of the present invention is not limited to the examples and / or related specifications provided, but is limited only by the claims relating to this disclosure.

Claims

1. Connecting the rotating member to the finger flange to form a finger flange / rotating member unit, The plunger cap is connected to the rotating member to form a finger flange / rotating member / plunger cap unit, This includes attaching the finger flange / rotating member / plunger cap unit to the filled syringe, wherein the filled syringe is The syringe body defines the inside of the syringe, The injection fluid placed inside the syringe, The syringe comprises a stopper member disposed inside the syringe and holding the injection fluid inside the syringe. Furthermore, the plunger member is inserted into the syringe through the finger flange / rotating member / plunger cap unit, This includes connecting the plunger member to the stopper member inside the syringe, A method for assembling an injection system, wherein the rotating member comprises a rotating member flange, the plunger member comprises a distal shoulder and a proximal thumb pad / external stop, and the rotating member flange and the distal shoulder are configured such that a distal force is applied to the plunger member by rotating the rotating member together with the injection system located vertically, thereby removing air from the syringe body, A method for assembling an injection system, characterized in that the proximal thumb pad / external stop and the rotating member flange define a gap such that the amount of injection solution delivered by the injection system is controlled by the size of the gap.

2. The aforementioned finger flange includes threads facing in the proximal direction, The method according to claim 1, further comprising connecting the rotating member to the finger flange and screwing the rotating member onto the proximal-facing thread on the finger flange to form the finger flange / rotating member unit.

3. The plunger cap defines the proximal opening, The aforementioned rotating member defines the opening of the rotating member, The aforementioned finger flange defines the finger flange opening, The method according to claim 1, further comprising inserting the plunger member into the syringe through the proximal opening, the rotating member opening, and the finger flange opening.

4. The rotating member has an inclined trough and a circumferential trough defined on its outer surface, The plunger cap is provided with a tongue that faces inward toward the longitudinal axis of the plunger cap, The method according to claim 3, further comprising connecting the plunger cap to the rotating member, screwing the plunger cap onto the rotating member such that the tongue of the plunger cap is positioned in the circumferential trough, and interference between the tongue and the circumferential trough prevents the plunger cap from moving proximal to the rotating member, thereby forming the finger flange / rotating member / plunger cap unit.

5. The finger flange is provided with a side opening, The syringe body is equipped with a syringe flange. The method according to claim 1, further comprising attaching the finger flange / rotating member / plunger cap unit to the syringe body by inserting the syringe flange of the syringe body into the side opening of the finger flange.

6. The stopper member is provided with a threaded stopper member recess. The plunger member includes a distal threaded member, The method according to claim 1, further comprising connecting the plunger member to the stopper member inside the syringe by screwing the distal threaded member of the plunger member into the threaded stopper member recess of the stopper member.

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