Syringe case with needle, syringe case and injection unit

Abstract

FIELD: ophthalmological medical instruments.SUBSTANCE: syringe case, needle case and injection unit. A syringe case with a needle containing the following components for attachment to the syringe: a positioning barrel for attachment to the flange of the syringe barrel and a connecting barrel. The connecting barrel has a connecting end and an injection end. The connecting end is used to connect with the positioning barrel. The injection end is used to limit the portion of the needle tip that protrudes from the connecting barrel. On the inside of the injection end there is an annular protrusion or the injection end has a tapered part for clamping the needle connector and limiting the needle. A syringe case containing a needle and the following components for attachment to the syringe: a positioning barrel for attachment to the flange of the syringe barrel and a connecting barrel. The connecting barrel has a connecting end and an injection end. The connecting end is configured to be connected to a positioning barrel. The injection end is connected to the needle via a needle connector and defines the portion of the needle tip that protrudes from the injection end. On the inner side of the injection end of the connecting barrel, an annular protrusion is formed, or the injection end of the connecting barrel has a tapered part for clamping the needle connector and limiting the needle. The injection unit comprises a syringe case with a needle and a syringe placed in a connecting barrel and a positioning barrel, wherein the flange of the syringe barrel is clamped in the mounting groove of the positioning barrel, and the length of the syringe needle protruding from the connecting barrel is adjusted by means of a connection between the connecting barrel and the positioning barrel or a connection between the connecting barrel and the needle connector. An object of the embodiments of the present invention is to provide a syringe case, a needle case, and an injection unit to overcome the drawback that the injection accuracy cannot be conveniently adjusted in existing syringes and to realize convenient adjustment of the injection accuracy. Another object of the embodiments of the present invention is to provide a syringe case, a needle case, and an injection unit so that the injection unit can be adjusted quickly, accurately, and easily, and there is no need to re-measure and confirm the penetration depth and position of the needle in the ocular tissue during use, thereby significantly saving time and labor costs. Another object of the embodiments of the present invention is to provide a syringe case, a needle case, and an injection unit that can ensure a stable position of the syringe by quickly positioning the injection unit during injection into the ocular tissue and avoid retraction of the needle or deviation of the injection position.EFFECT: equipment for ensuring accurate, stable and quick positioning during injection.16 cl, 31 dwg, 3 tbl

Description

[0001] FIELD OF INVENTION

[0002] The present invention relates to the technical field of ophthalmological medical instruments, in particular to a syringe case, a needle case, an injection unit and a method for using them.

[0003] STATE OF THE ART

[0004] The eye is a highly complex visual organ, comprising the eyeball, the optic tract, and the adnexa, in which the eyeball and optic tract perform visual function. The eyeball consists of a wall and a lining, is roughly spherical, and has a highly complex structure. The wall of the eyeball consists of three layers: the outer layer, called the fibrous tunic, the middle layer, called the uvea, and the inner layer, called the retina. The fibrous tunic is composed primarily of fibrous tissue and is the outer layer of the eyeball. The fibrous tunic consists of the cornea and sclera, with the sclera accounting for five-sixths of the eyeball's surface. The sclera is strong yet flexible and is formed by dense, interwoven fibers. The thickness of the sclera varies in different parts and has individual specificities. At different stages of development, including childhood, adulthood and old age, the arrangement of collagen fiber bundles in the sclera varies in different parts of the eyeball.As an exposed organ, the eye is vulnerable to conjunctival or corneal damage caused by various pathogens. For example, the conjunctiva is a thin, transparent, highly vascular mucous membrane that lines the inner surface of the eyelid and the anterior aspect of the eyeball and helps protect the eyeball from injury, foreign bodies, and infection. However, the mucous membrane itself is very sensitive, easily irritated by chemicals or allergens, or infected by viruses and bacteria, causing conjunctivitis. Furthermore, the abundant blood vessels in the mucous membrane can inject large amounts of drugs (>60%) into the systemic circulation, easily causing unnecessary tissue toxicity.

[0005] Currently, ocular diseases are one of the major causes of irreversible visual impairment or injury, mainly including neovascular and age-related macular degeneration, diabetic retinopathy, diabetic macular edema, central retinal vein occlusion and branch retinal vein occlusion, etc. In the treatment of ocular diseases, given that tissue barriers (e.g., corneal, conjunctival, blood-aqueous barrier, and blood-retinal barrier) limit drug delivery to the fundus, ophthalmic drug delivery devices play a key role in drug delivery. Although existing delivery methods, such as ocular surface injection and intravitreal injection (IVT), are convenient, they are difficult to use to effectively and safely deliver drugs to fundus lesions.Furthermore, if the puncture is performed in the wrong position or at the wrong angle when injecting into the eye, this can lead to complications such as intraocular hemorrhage or retinal damage, which can lead to cataracts and retinal detachment. If medication leaks, it can cause infection in other ocular tissues.

[0006] As described above, drug delivery to the eye has always been a challenging issue due to the unique structure of the eye. Delivering drugs to the suprachoroidal space is particularly challenging due to its structure. The suprachoroidal space is a potential luminal gap between the sclera and the choroid, and there is no apparent luminal gap when there is no fluid and / or tissue separation. When fluid or other material accumulates between the choroid and sclera, a suprachoroidal space may appear in this area. Therefore, fluid accumulation is intentionally created by delivering, injecting, and / or infusing drugs into the suprachoroidal space to further create and / or enlarge the suprachoroidal space formed by separation of the choroid from the sclera.Local choroidal hemorrhage may occur during injection during drug administration into the suprachoroidal space, leading to retinal damage. In addition, the injection may cause complications such as endophthalmitis, scleral dilation, wound abscess, etc., and may also sometimes cause increased intraocular pressure and cataracts.

[0007] Ocular tissue injection places high demands on the precision of the distance between the syringe itself and the ocular tissue, as well as the penetration depth and needle position. The operator can achieve precise positioning before injection. However, with existing ocular tissue injection methods, the penetration depth and needle position must be confirmed and re-measured before injection. To meet the precision requirements when using a syringe, the syringe operator often requires a significant amount of time and effort to complete the syringe positioning in the eye, as it is inconvenient to make adjustments. On the other hand, to ensure the needle penetrates the eye, the operator can apply a certain amount of force to the syringe while wearing gloves during surgery, but slippage between the syringe and the gloves can easily occur.In addition, when the needle penetrates the ocular tissue, it is difficult to accurately position the syringe, and the needle may move backward or be displaced from the injection position under the influence of the ocular tissue; therefore, the desired injection effect may not be achieved, or accidents may even occur.

[0008] SUMMARY OF THE INVENTION

[0009] The embodiments of the present invention aim to provide a syringe case, a needle case, and an injection unit that overcome the problem of the injection accuracy being difficult to adjust in existing syringes and achieve convenient adjustment of injection accuracy. Another objective of the embodiments of the present invention is to provide a syringe case, a needle case, and an injection unit that allows for quick, accurate, and easy adjustment of the injection unit, eliminating the need to repeatedly measure and confirm the penetration depth and position of the needle in the ocular tissue during use, thereby significantly saving time and labor.Another object of the embodiments of the present invention is to provide a syringe case, a needle case, and an injection unit that can ensure a stable position of the syringe by quickly positioning the injection unit during injection into the ocular tissue and avoid retraction of the needle or deviation of the injection position.

[0010] In order to achieve the above objectives, the following technical schemes are proposed in the embodiments of the present invention:

[0011] The first aspect provides a syringe case that is designed to be mounted on the outside of a syringe. The syringe comprises a barrel with a flange and may have a needle; the syringe case comprises a positioning cylinder for fixed connection with the flange of the syringe barrel and a connecting cylinder, wherein the connecting cylinder comprises a connecting end for connection with the positioning cylinder and an injection end for defining a portion of the needle tip protruding from the connecting cylinder.

[0012] Using a syringe case, the syringe barrel flange can be rigidly connected to the positioning cylinder through the structure of the existing syringe. The syringe and positioning cylinder can then be connected. This allows the operator to grasp the syringe instead of grasping the syringe case, thereby making use and operation more convenient. By positioning the syringe case, the syringe can be positioned correctly during injection into the ocular tissue. This ensures a stable position of the syringe and prevents it from moving backward or deviating from the injection position.

[0013] In a preferred embodiment of the present invention, when the connecting cylinder and the positioning cylinder are connected, the overall length of the connecting cylinder and the positioning cylinder can be changed by means of the connection.

[0014] The overall length of the connecting cylinder and the positioning cylinder can be conveniently adjusted by connecting the connecting cylinder and the positioning cylinder. From the initial position and state of connection to the final position and state of connection, the overall length of the connecting cylinder and the positioning cylinder can be changed at least once, thereby realizing the change in the overall length of the connecting cylinder and the positioning cylinder. The injection end of the connecting cylinder limits the relative position of the needle, and the tip of the needle can protrude from the connecting cylinder. The length of the extended tip of the needle can be adjusted by adjusting the relative position of the connecting cylinder and the positioning cylinder.Since the total length of the connecting cylinder and positioning cylinder in the final connected state is determined in the prefabrication stage, and the syringe and needle lengths are also determined in the prefabrication stage, the length of the extended needle tip can be determined using the parameters in the prefabrication stage. When the connecting cylinder and positioning cylinder are connected, the final exposed needle tip length is the needle tip length required for ocular tissue injection. This ensures that the needle tip positioning meets the requirements for ocular tissue injection. Furthermore, connecting and adjusting the syringe case can be completed quickly, eliminating the need for repeated measurements and confirmations during use, significantly saving time and labor.

[0015] The term "limiting" in this document refers to fixing the portion of the needle tip protruding from the injection end of the connecting barrel in such a way as to avoid any change in the length of the protruding needle tip or any vibration of the needle during the injection process.

[0016] In a preferred embodiment of the present invention, the needle has a connector, and an annular projection is provided on the inside of the injection end of the connecting barrel for clamping the connector to limit the needle. Using the annular projection, the injection end of the connecting barrel can limit the length of the needle protruding from the connecting barrel, thereby limiting the length of the exposed tip of the needle to meet injection requirements.When the connecting cylinder and the positioning cylinder interact, the annular projection allows the syringe in the positioning cylinder to quickly connect with the needle connector to form an integral structure and lock the connector; thus, during the injection process into the eye, the needle can be prevented from moving backward toward the syringe or from deviating from the injection position under the influence of tissues at the injection site, which would otherwise lead to inaccurate injection dosage and affect the injection effect; furthermore, when the operator applies pushing force to the pusher to move the pusher in the syringe, the tip of the needle cannot move along with the plunger of the syringe because the connector is clamped by the annular projection, and the needle cannot be excessively advanced into the target eye tissue, which would otherwise cause injury to the target eye tissue or penetration through the target eye tissue.

[0017] In a preferred embodiment of the present invention, the needle connector's upper end is provided with raised ribs to protect against the annular projection and limit the length of the needle protruding from the injection end through the annular projection. The arrangement of the raised ribs, which can abut against the annular projection, facilitates clamping of the connector in the injection end of the connecting barrel.

[0018] In a preferred embodiment of the present invention, the tip of the injection end has a clamping hole for pressing the ocular tissue at the injection site, and the clamping hole has an annular end surface with a minimum inner diameter of 1 mm to 3 mm. During use, the needle penetrates the injection point to perform an injection; the minimum inner diameter of the annular end surface of the clamping hole refers to the length of the shortest line segment that passes through the injection point and has two ends located respectively inside the clamping hole, and the injection point is located at the center of the line segment. Experimental results show that when the minimum inner diameter is 1 mm to 3 mm, the area of ​​​​the ocular tissue in the clamping hole is suitable, and the ocular tissue in the clamping hole can form an obvious protrusion, which can facilitate the injection operation.The clamp hole can facilitate contact with the ocular tissue and fix the position of the syringe, so that the injection success rate can be improved and the drug solution can be successfully delivered to the target site.

[0019] In a preferred embodiment of the present invention, the injection end of the connecting cylinder has a cavity, wherein one end of the cavity is sealed by a needle seat, and the other end of the cavity is sealed by compression between the ocular tissue and the clamping hole. With this cavity arrangement, when reflux occurs, the refluxed medicinal solution is contained in the sealed cavity; when the clamping hole is separated from the ocular tissue, the refluxed medicinal solution will not easily leak out of the cavity, thereby effectively preventing diffusion of the refluxed drug onto the ocular surface due to injection failure.

[0020] In a preferred embodiment of the present invention, the side wall of the injection end of the connecting barrel has a viewing window made of a transparent material, or the injection end is a component made of a transparent material; with a viewing window or a component made of a transparent material, it is convenient to observe the backflow of the medicinal solution and quickly judge the success of the injection.

[0021] In a preferred embodiment of the present invention, the connecting end of the connecting cylinder can be connected to the positioning cylinder via a threaded connection or a snap-in connection. The threaded connection or the snap-in connection can realize the connection between the connecting cylinder and the positioning cylinder; in addition, the overall length can be adjusted at least once or can be continuously adjusted from the initial state or the state of incomplete connection to the final state of connection of the connecting cylinder and the positioning cylinder, and the overall length of the connecting cylinder and the positioning cylinder can be adjusted to the expected value, so that the open tip length of the needle can be adjusted according to the sclera thickness of different patients to meet the injection requirements.

[0022] In a preferred embodiment of the present invention, the connecting end of the connecting cylinder is connected to the end of the positioning cylinder facing the needle, or the connecting cylinder is inserted into the positioning cylinder and connected to it from the end of the positioning cylinder facing the tail end of the syringe pusher. According to the two connection methods, different connection modes or different processes for using the connecting cylinder and the positioning cylinder can be provided, and the scope of application of the syringe case is expanded.

[0023] In a preferred embodiment of the present invention, the connecting end of the connecting cylinder has an external thread, the positioning cylinder has an internal thread, and the connecting end can be connected to the positioning cylinder by rotation, allowing the overall length of the connecting cylinder and the positioning cylinder to be adjusted by rotation. The threaded connection allows the relative lengths of the connecting cylinder and the positioning cylinder to be adjusted, thereby adjusting the overall length.

[0024] In a preferred embodiment of the present invention, when the connecting cylinder is configured to be inserted into the positioning cylinder and connected to it from the end of the positioning cylinder facing the tail end of the syringe rod, after the syringe is installed, the flange of the syringe barrel abuts the connecting end of the connecting cylinder and restricts the reverse movement of the connecting end in the positioning cylinder. By clamping the flange of the syringe barrel on the positioning cylinder, the syringe can be integrated with the positioning cylinder, and the position of the connecting end of the connecting cylinder in the positioning cylinder can be adjusted.The final position of the backward movement of the connecting end is a position in which the tip of the connecting end abuts against the flange of the syringe barrel, and the connecting end cannot move backward further, thus realizing the backward movement prevention function of the syringe case.

[0025] In a preferred embodiment of the present invention, the inner wall of the connecting cylinder has a positioning groove extending in the axial direction for mutual clamping with the outer side of the syringe barrel or the outer side of the needle connector, so that the syringe can move in the axial direction of the connecting cylinder when guided by the positioning groove. Using the positioning groove, the connecting cylinder can provide at least one passage in the axial direction that can accommodate the outer side of the syringe barrel or the outer side of the needle connector, so that the syringe can be guided for movement in the connecting cylinder only in the direction of the central axis, and the needle cannot come into contact with the inner wall of the connecting cylinder during movement, which is useful for maintaining the cleanliness of the needle.

[0026] In a preferred embodiment of the present invention, a protrusion is formed on the outer side of the needle connector, the shape and size of which correspond to the cross-section of the positioning groove; by fitting between the structure of the protrusion on the outer side of the connector and the positioning groove, the needle can move in the axial direction in the connecting cylinder together with the positioning groove, and the syringe always moves in one direction without oscillating under the direction of the needle when the syringe is placed at the injection site; thus, contact between the needle and the inner wall of the connecting cylinder during the placement of the syringe is eliminated.

[0027] In a preferred embodiment of the present invention, the positioning cylinder has a mounting groove for receiving a syringe barrel flange, such that said flange is rotationally clamped in the mounting groove. The syringe barrel flange can be conveniently clamped in the positioning cylinder for connection via the mounting groove, so that the syringe barrel and the positioning cylinder are firmly connected.

[0028] In a preferred embodiment of the present invention, the positioning cylinder has a flange mounting platform for supporting one side of the syringe barrel flange and a locking projection for clamping the other side of the syringe barrel flange, wherein the gap between the locking projection and the flange mounting platform forms an installation groove; when the flange mounting platform and the locking projection are positioned on the positioning cylinder, a space is formed for clamping the syringe barrel flange, so that the syringe can be conveniently fixed on the positioning cylinder.

[0029] In a preferred embodiment of the present invention, an arcuate protruding structure is formed at the upper portion of the flange mounting platform or at the lower portion of the locking projection for fixing the flange of the syringe barrel on one side; with the arcuate protruding structure, when the flange of the syringe barrel is rotationally clamped in the installation groove, the flange mounting platform or the locking projection can be tightly pressed against the surface of the flange of the syringe barrel, so that the syringe barrel is clamped and fixed in the installation groove and is held in a locked state after it is clamped in the installation groove; thus, the syringe can be prevented from being detached from the positioning cylinder.

[0030] In a preferred embodiment of the present invention, a limiting structure is provided on the outside of the positioning cylinder to secure the operator's fingers. This limiting structure can be a protrusion, recess, or ring. The outer diameter of an ophthalmic syringe is typically several millimeters, requiring the operator to wear gloves and manipulate the syringe directly. However, handling the syringe barrel while wearing rubber gloves is inconvenient, often resulting in an unstable grip and slippage. The limiting structure ensures comfortable finger placement, allowing the operator to comfortably hold the syringe case, facilitating operation.

[0031] In a preferred embodiment of the present invention, the needle may have various specifications, and the needle shafts of different specifications vary in length and may be 5 to 10 mm long. Needles of different specifications are provided by adjusting the needle shaft length. Thus, the operator can select needles of different specifications according to different situations and the needs of different patients.

[0032] In a preferred embodiment of the present invention, the injection end of the connecting cylinder has a tapered section for clamping the needle connector and restricting the needle. The inner opening of the tapered section is small, and the injection end can clamp the upper end of the connector to restrict further movement of the connector, thereby realizing the needle restriction function. Furthermore, the injection end allows the needle shaft to pass through it, so that the needle tip can be exposed at the injection end of the connecting cylinder after the connecting cylinder is connected to the positioning cylinder. The syringe case can replace the initial operation of the operator gripping the syringe with the operation of the operator gripping the syringe case, thereby making use and operation more convenient.The total length of the connecting cylinder and the positioning cylinder can be conveniently adjusted by the connection between the connecting cylinder and the positioning cylinder, so that the length of the open tip of the needle can be adjusted by adjusting the relative position of the connecting cylinder and the positioning cylinder so that the tip of the needle is located in the desired position, and the length of the open tip of the needle can meet the requirements of injection into the ocular tissue.

[0033] When the connecting cylinder and the positioning cylinder cooperate to adjust the open length of the needle tip and limit the position of the needle, the syringe in the positioning cylinder can be quickly connected to the needle connector to form a single structure and lock the needle connector; thus, during the injection process into the eye, it can avoid the needle from moving backward toward the syringe or being deflected from the injection position by the tissue at the injection site, which would cause inaccurate injection dosage and affect the injection effect; moreover, when the operator applies pushing force to the pusher to move the pusher in the syringe, the tip of the needle cannot move along with the syringe pusher, because the syringe locks the connector, and the needle cannot be excessively extended into the target eye tissue, which would cause injury to the target eye tissue or penetration through the target eye tissue.

[0034] In a preferred embodiment of the present invention, the syringe case connects the positioning cylinder and the connecting cylinder in such a way that the syringe clamps the needle, thereby preventing inaccurate dosing during injection due to the needle moving backward toward the syringe or the needle being deflected from the injection position under the influence of tissues at the injection site during the injection process.

[0035] In a preferred embodiment of the present invention, the syringe case connects the positioning cylinder and the connecting cylinder in such a way that the tip of the needle does not move when the pusher is moved, thereby preventing further advancement of the needle into the target tissue of the eye, thereby preventing injury to the target tissue of the eye or penetration through the target tissue of the eye.

[0036] The second aspect provides a needle sheath. The sheath is designed to be attached to a syringe from the outside. The syringe comprises a barrel with a flange, and the needle has a connector; the syringe sheath comprises a positioning cylinder for attaching to the flange of the syringe barrel and a connecting cylinder, wherein the connecting cylinder comprises a connecting end for connecting to the positioning cylinder and an injection end connected therein to the connector for defining a portion of the needle tip protruding from the connecting cylinder.

[0037] In a preferred embodiment of the present invention, when the injection end and the connector are connected, the total length of the injection end and the connector can be changed by connecting.

[0038] The syringe case directly connects the needle to the connecting barrel and limits the open tip length of the needle with the injection end. Therefore, since the injection end length of the connecting barrel and the needle are determined in the pre-fabrication stage, the open tip length of the needle when the connecting barrel and needle are in the final connection state can be determined by the parameters in the pre-fabrication stage. When the connecting barrel and needle are connected in the final state, the open tip length of the needle is the length of the needle tip required for injection into the eye. This allows the needle tip to be positioned correctly, thereby meeting the injection requirements for ocular tissue. The connection and adjustment of the syringe case with the needle can be completed quickly, and there is no need to repeat the measurement and confirmation during use, thereby greatly saving time and labor.

[0039] When the connecting cylinder and the positioning cylinder cooperate to adjust the open length of the needle tip and limit the position of the needle, the syringe in the positioning cylinder can be quickly connected to the needle connector, forming a single structure, and locking the needle connector; thus, it can avoid the needle from moving backward toward the syringe or deviating from the injection position under the influence of the tissue at the injection site, which would lead to inaccurate injection dosage and affect the injection effect, during the process of injection into the eye; moreover, when the operator applies pushing force to the pusher to move the pusher in the syringe, the tip of the needle cannot move along with the plunger of the syringe, because the syringe locks the connector, and the needle cannot be excessively extended into the target tissue in the eye, which would cause injury to the target tissue in the eye or penetration through the target tissue in the eye.

[0040] The third aspect provides an injection unit. The injection unit comprises the above-mentioned syringe case or the above-mentioned case with a needle and a syringe, wherein the syringe is located in a connecting cylinder and a positioning cylinder, and the flange of the syringe barrel is clamped in a mounting groove; wherein the length of the syringe needle protruding from the connecting cylinder can be adjusted by a connection between the connecting cylinder and the positioning cylinder or a connection between the connecting cylinder and the needle connector.The injection unit can be connected to an existing syringe, thereby conveniently adjusting the length of the needle tip for injection into the ocular tissue to the required length and accuracy, making it easier for the operator to operate with one hand, and making the use and operation more convenient. Moreover, when the connecting cylinder and the positioning cylinder cooperate to adjust and limit the length of the exposed needle tip, the syringe in the positioning cylinder can be quickly connected to the needle connector to form a single structure, and the needle connector is locked.

[0041] The fourth aspect provides a method for using a syringe case. The method uses the above-mentioned syringe case or the above-mentioned case with a needle, wherein the method comprises the following steps: first, connecting a connecting cylinder with a positioning cylinder, then placing a syringe barrel in the connecting cylinder and the positioning cylinder, and then clamping the flange of the syringe barrel in the installation groove for fixation; alternatively, first putting the positioning cylinder on the outside of the syringe barrel, then clamping the flange of the syringe barrel in the installation groove for fixation, and then connecting the connecting cylinder with the positioning cylinder; by this method, the positioning cylinder and the syringe can be fixed relative to each other to form a case outside the syringe, to obtain a single structure combining the syringe and the case, so as to facilitate the use and operation of the operator; in addition, the syringe can lock the needle connector;thus, during the injection, inaccurate dosing will not occur as a result of the needle moving backwards towards the syringe or the needle being deflected from the injection position under the influence of the tissues at the injection site during the injection process.

[0042] In the process when the operator applies a pulling force to the syringe pusher to move the pusher in the syringe, because the needle connector is locked, the proposed sheath prevents the needle tip from moving along with the movement of the pusher, so as to avoid excessive damage to the target eye tissue or penetration through the target eye tissue due to further advancing the needle into the target eye tissue.

[0043] In a preferred embodiment of the present invention, the overall length of the connecting cylinder and the positioning cylinder is adjusted by a connection between the connecting cylinder and the positioning cylinder, or the overall length of the connecting cylinder and the needle connector is adjusted by a connection between the connecting cylinder and the connector, thereby adjusting the relative length of the needle tip protruding from the injection end of the connecting cylinder; an assembled unitary structure is formed by a connection between the connecting cylinder and the positioning cylinder, and the unitary structure makes it possible to adjust the overall length of the connecting cylinder and the positioning cylinder by a connection between the connecting cylinder and the positioning cylinder, thereby adjusting the length of the exposed tip of the needle.

[0044] In a preferred embodiment of the present invention, after the flange of the syringe barrel has moved to a position corresponding to the mounting groove during use, the flange of the syringe barrel is rotated together with the connecting cylinder, or the flange of the syringe barrel is rotated and clamped in the mounting groove by manual rotation, and then the syringe barrel is fixed by a positioning cylinder; by clamping by rotating the syringe, the syringe barrel can be quickly and conveniently connected and fixed by the positioning cylinder, and the locking can be realized by clamping.

[0045] The fifth aspect provides a method for using the above-mentioned injection unit. The method comprises the steps of selecting a syringe with a needle of a certain specification according to requirements and then fixing the syringe to a positioning cylinder; and adjusting the length of the needle tip protruding from the connecting cylinder by adjusting the overall length of the connection between the connecting cylinder and the positioning cylinder or the overall length of the connecting cylinder and the needle connector. By selecting syringes with needles of different specifications, the needs of people of different ages and different patients with different actual ocular tissue thicknesses can be met.

[0046] In the sixth aspect, a method for using the above-mentioned injection unit is provided. The method comprises the following steps: selecting a needle of a certain specification according to requirements and placing the needle in a connecting cylinder; forcibly moving the needle to the injection end of the injection cylinder, and adjusting the length of the needle tip protruding from the connecting cylinder by adjusting the overall length of the connection between the connecting cylinder and the positioning cylinder or the overall length of the connecting cylinder and the needle connector.The operator can quickly select a needle of a certain specification according to the patient's scleral thickness and accurately adjust the open tip length of the needle through the connector as needed. This allows the operator to quickly select the needle and safely complete the assembly, meeting the needs of people of different ages and different patients with different actual ocular tissue thickness parameters, and improving the injection success rate.

[0047] In a preferred embodiment of the present invention, when the connecting cylinder is connected to the positioning cylinder via a thread from the end of the positioning cylinder facing the tail of the syringe plunger, the length of the needle tip protruding from the positioning cylinder can be adjusted by rotating the positioning cylinder in the reverse direction, assuming that the rotation direction of the positioning cylinder during connection is positive. By changing the rotation mode of the positioning cylinder, the connection between the positioning cylinder and the positioning cylinder is divided into two stages: one stage is a rotational connection for connecting the connecting cylinder and the positioning cylinder; the other stage is a reverse rotation for adjusting the overall length of the connecting cylinder and the positioning cylinder, thereby adjusting the length of the exposed tip of the needle.

[0048] In a preferred embodiment of the present invention, the open tip length of the needle is 500-2000 μm, preferably 700-1350 μm, more preferably 700-1100 μm.

[0049] In a preferred embodiment of the present invention, the length of the blade tip of the needle is less than or equal to 1100 μm, preferably less than or equal to 900 μm, even more preferably less than or equal to 700 μm, even more preferably less than or equal to 550 μm, optimally 250 - 550 μm.

[0050] In a preferred embodiment of the present invention, the method further comprises: holding the fingers by means of a limiting structure; holding the syringe case in the hand and creating contact of the clamping hole with the eye tissue at the injection site by pressing it, so that the eye tissue at the injection site protrudes into the connecting cylinder; then forcibly piercing the eye tissue at the injection site with the tip of the needle into the target eye tissue; and manipulating the syringe pusher to push the drug into the target tissue.The fingers can be fixed on the outside of the case by means of a limiting structure; thus, the fingers of one hand can be conveniently fixed on the case, and the eye tissue can be in contact and fixed by pressing through the clamping hole, so that the tip of the needle can penetrate the target tissue; thus, the operator can operate with one hand conveniently to inject the drug into the eye tissue.

[0051] The syringe case, needle case, injection unit, and method of using the same, provided in the embodiments of the present invention, can be widely used for eye diseases and related diseases. Eye diseases include, but are not limited to, uveitis, glaucoma, diabetic macular edema, retinopathy, macular degeneration, retinoblastoma, and genetic diseases.

[0052] In the present application, ocular diseases can be treated by inserting a needle into the scleral tissue of a patient to an effective length and delivering a drug into the suprachoroidal space through the inserted needle using any device or method. In some embodiments, the effective amount of a drug introduced into the suprachoroidal space provides a higher therapeutic efficacy of the drug compared to the therapeutic efficacy achieved by administering the same amount of the drug intravitreally, topically, intravenously, parenterally, or orally. The drug is precisely delivered into the suprachoroidal space by any device or method proposed in embodiments of the present invention for subsequent local delivery to nearby posterior ocular tissues (e.g., the retina and choroid) in need of treatment.For a period of time following drug administration, such as several hours, several days, several weeks, or several months, the drug may be continuously released into the ocular tissue. In some embodiments, compared to oral, parenteral, or intravitreal administration of the same drug dosage, any device or method provided in embodiments of the present invention may also improve drug bioavailability by local administration to ocular tissue.

[0053] The syringe case, the needle case, the injection unit and the method of using them, presented in the embodiments of the present invention, are particularly suitable for delivering drugs to local posterior regions of the eyes, such as the retina and choroid, the macula and the optic nerves in the posterior parts of the eyes. The syringe case, the needle case, the injection unit and the method of using them, presented in the embodiments of the present invention, can also be used in gene therapy, in which a medical solution containing therapeutic gene fragments is delivered to the suprachoroidal space, and the therapeutic gene fragments are delivered to the target tissue of the eye in any one or more carriers selected from DNA, RNA or oligonucleotides.

[0054] As used herein, the term "medicinal product" refers to any prophylactic, therapeutic, or diagnostic agent (e.g., a contrast agent). The medicinal product may be selected from suitable proteins, peptides, or fragments thereof, which may be natural, synthesized, or recombinantly produced.

[0055] In some embodiments of the present invention, the syringe contains a medicinal solution of one or more pharmaceutically active substances, which can be selected from antibodies, antiviral agents, chemotherapeutic agents, analgesics, anesthetics, aptamers, antihistamines, anti-inflammatory agents and antitumor agents.

[0056] As used herein, the term "antibody" generally refers to any immunoconjugator, such as IgG, IgM, IgA, IgD, and IgE. Antibodies can be monoclonal or polyclonal, and in some embodiments are humanized antibodies. The term "antibody" also refers to any antibody-like molecule that has an antigen-binding region and includes antibody fragments such as Fab", Fab, F(ab")2, single-domain antibody (DAB), Fv, scFv (single-chain Fv), and engineered multivalent antibody fragments such as divalent antibody, trivalent antibody, and multivalent antibody. Techniques for producing and using antibodies and various antibody-based structures and fragments are well known in the art.

[0057] In some embodiments of the present invention, the syringe comprises one or more genetic therapeutic drugs that use recombinant adeno-associated viruses (rAAV) as carriers, and the AAV is selected from AAV1, AAV2, AAV3, AAV4, AAV5, AAV6, AAV7, AAV8, AAV9, AAV10 or mutants thereof; preferably, the AAV is AAV8 or mutants thereof. The recombinant adeno-associated virus rAAV preferably comprises drugs intended for the treatment of ocular diseases, such as anti-VEGF drugs, complement factor inhibitors (complement component C3, complement factor B and complement factor D), plasma kallikrein inhibitors, PDGFR inhibitors, tyrosine kinase inhibitors, integrin inhibitors, angiopoietin-2 inhibitors and Tie-2 agonists.

[0058] In some embodiments of the present invention, the syringe is a pre-filled syringe, which not only prevents operator injury or inaccurate dosage during dosing and reduces the possibility of misuse of the drug, but also effectively reduces the amount of residual drug solution, making the dosage of the drug more accurate, and prevents air from contacting the drug, thereby avoiding cross-contamination.

[0059] The seventh aspect provides a kit. The kit comprises a vial containing a medicinal solution and an injection unit, wherein the injection unit uses the above-mentioned syringe case or the above-mentioned needle case, wherein the syringe is disposed in a connecting cylinder and a positioning cylinder, and the flange of the syringe barrel is clamped in a mounting groove; the length of the syringe needle protruding from the connecting cylinder can be adjusted by a connection between the connecting cylinder and the positioning cylinder or a connection between the connecting cylinder and the needle connector; the injection unit can be combined with an existing syringe, thereby conveniently adjusting the length of the needle tip for injection into the ocular tissue to the required length and accuracy, making it easier for the operator to operate with one hand, and making use and operation more convenient.Moreover, when the connecting cylinder and the positioning cylinder cooperate to adjust and limit the length of the exposed tip of the needle, the syringe in the positioning cylinder can be quickly connected to the needle connector to form a single structure, and the needle connector is locked.

[0060] In some embodiments of the present invention, the medicinal solution is a medicinal solution containing one or more pharmaceutically active substances that can be selected from antibodies, antiviral agents, chemotherapeutic agents, analgesics, anesthetics, aptamers, antihistamines, anti-inflammatory agents, and antitumor agents.

[0061] In some embodiments of the present invention, the vial contains one or more genetic therapeutic drugs that use recombinant adeno-associated viruses (rAAV) as carriers, and the AAV is selected from AAV1, AAV2, AAV3, AAV4, AAV5, AAV6, AAV7, AAV8, AAV9, AAV10 or mutants thereof; preferably, the AAV is AAV8 or mutants thereof. rAAV preferably contains drugs expressed for the treatment of ocular diseases, such as anti-VEGF drugs, complement factor inhibitors (complement component C3, complement factor B and complement factor D), plasma kallikrein inhibitors, PDGFR inhibitors, tyrosine kinase inhibitors, integrin inhibitors, angiopoietin-2 inhibitors and Tie-2 agonists.

[0062] In the eighth aspect, a kit is provided. The kit comprises a pre-filled injection unit that uses the above-mentioned syringe case or the above-mentioned case with a needle and a pre-filled syringe, wherein the pre-filled syringe is disposed in a connecting cylinder and a positioning cylinder, and the flange of the syringe barrel of the pre-filled syringe is clamped in the installation groove; and the length of the needle of the pre-filled syringe protruding from the connecting cylinder can be adjusted by the connection between the connecting cylinder and the positioning cylinder or the connection between the connecting cylinder and the needle connector;The pre-filled injection unit can be combined with the existing pre-filled syringe, thereby conveniently adjusting the length of the needle tip for injection into the ocular tissue to the required length and accuracy, making it easier for the operator to operate with one hand, and making the use and operation more convenient; Moreover, when the connecting cylinder and the positioning cylinder cooperate to adjust and limit the length of the exposed needle tip, the pre-filled syringe in the positioning cylinder can be quickly connected to the needle connector, forming a single structure, and the needle connector is locked.

[0063] In some embodiments of the present invention, the pre-filled syringe is pre-filled with a pharmaceutical solution of one or more pharmaceutically active substances, which may be selected from antibodies, antiviral agents, chemotherapeutic agents, analgesics, anesthetics, aptamers, antihistamines, anti-inflammatory agents and antitumor agents.

[0064] In some embodiments of the present invention, the prefilled syringe is prefilled with one or more genetic therapeutic drugs that use recombinant adeno-associated viruses (rAAV) as carriers, and the AAV is selected from AAV1, AAV2, AAV3, AAV4, AAV5, AAV6, AAV7, AAV8, AAV9, AAV10 or mutants thereof; preferably, the AAV is AAV8 or mutants thereof. Preferably, the rAAV contains drugs intended for the treatment of ocular diseases, such as anti-VEGF drugs, complement factor inhibitors (complement component C3, complement factor B and complement factor D), plasma kallikrein inhibitors, PDGFR inhibitors, tyrosine kinase inhibitors, integrin inhibitors, angiopoietin-2 inhibitors and Tie-2 agonists.

[0065] The technique of filling a pre-filled syringe with a medicinal solution in the present invention is well known in the art.

[0066] Compared with the prior art, embodiments of the present invention achieve the following advantageous effects.

[0067] 1. The syringe case / syringe case with a needle provided in the embodiments of the present invention utilizes the structure of the existing syringe, integrates the syringe with the case, and changes the operation of the operator gripping the syringe to the operation of the operator gripping the syringe case, which is more convenient for use and operation; by positioning the syringe case, the syringe can be positioned during injection into the ocular tissue, thereby ensuring a stable position of the syringe and preventing the syringe from moving backward or deviating from the injection position.In addition, the annular protrusion on the inner side of the injection end of the connecting cylinder is provided with raised ribs located on the periphery of the upper end of the connector, so that the length of the needle tip protruding from the injection end of the connecting cylinder can be changed, thereby the needle tip can be accurately positioned, and the requirements of injection into the ocular tissue can be met; in addition, the connection and adjustment can be completed quickly, and the syringe can lock the needle connector; there is no need to conduct repeated measurement and confirmation during use, which greatly saves time and labor; during injection, inaccurate dosage will not occur due to the reverse movement of the needle toward the syringe or the deviation of the syringe from the injection position due to the impact of tissues at the injection site during injection into the ocular tissue.

[0068] 2. The syringe case proposed in the embodiments of the present invention is connected to the positioning cylinder or the needle connector through the connecting end of the connecting cylinder, and the length of the open tip of the needle can be adjusted by adjusting the total length of the connecting cylinder and the positioning cylinder or the total length of the connecting cylinder and the needle connector.

[0069] 3. The syringe case provided in the embodiments of the present invention can facilitate the positioning of fingers, and the operator can comfortably hold the syringe case and fix the fingers relative to the syringe case, thereby making the operation more convenient.

[0070] 4. The syringe case proposed in the embodiments of the present invention can be integrated with the positioning cylinder by clamping the flange of the syringe barrel to the positioning cylinder, and the position of the connecting end of the connecting cylinder in the positioning cylinder can be adjusted. The final position of the backward movement of the connecting end is a position in which the tip of the connecting end abuts the flange of the syringe barrel, and the connecting end cannot move further backward, thereby realizing the backward movement prevention function of the syringe case.

[0071] 5. The injection unit proposed in the embodiments of the present invention integrates a sheath with an existing syringe, thereby meeting various usage requirements by selecting needles with different length specifications; thus, the length of the exposed tip of the needle can be adjusted through the connecting structure of the sheath itself; when the sheath is adjusted to the correct position, the length of the exposed tip of the needle reaches the required value and accuracy, and meets the requirements of injection into the eye; in addition, the injection unit is convenient for the operator because it can be operated with one hand, and is more convenient to use and operate.

[0072] 6. The method of using a syringe case proposed in the embodiments of the present invention can realize the relative fixation between the positioning cylinder and the syringe, form a case outside the syringe, and provide a single structure combining the syringe with the case, which is convenient for the operator to operate and use.

[0073] 7. The method of using the injection unit proposed in the embodiments of the present invention can meet the needs of people of different ages and different patients with different actual ocular tissue thickness parameters by selecting syringes with needles of different specifications; in addition, the open length of the needle tip can be adjusted by the total length of the connecting cylinder and the positioning cylinder or the total length of the connecting cylinder and the needle connector; thus, the needle can successfully reach the predetermined position of the ocular tissue, ensure the injection effect, and improve the injection success rate.

[0074] 8. The injection unit proposed in the embodiments of the present invention integrates a sheath with an existing syringe, the tip of the needle will not move back toward the syringe or swing during penetration and cause the needle to deviate from the injection position; the tip of the needle will not move when a pressing force is applied to the plunger of the syringe to move the plunger in the syringe; thus, the tip of the needle cannot be excessively extended in the target tissue of the eye, which could lead to injury to the target tissue of the eye or penetration through the target tissue of the eye.

[0075] BRIEF DESCRIPTION OF DRAWINGS

[0076] To more clearly explain the technical diagrams in the embodiments of the present invention and in the prior art, the drawings used in the description of the embodiments and the prior art are briefly presented below. Obviously, the drawings used in the description below illustrate only some embodiments of the present invention, and those with ordinary skill in the art can develop other drawings based on these drawings without any creative effort.

[0077] Fig. 1 is a schematic exploded view of a syringe case provided in Embodiment 1 of the present invention;

[0078] Fig. 2 is a schematic view of a needle used in a syringe case in Embodiment 1 of the present invention;

[0079] Fig. 3 is a schematic sectional view of the injection end of the syringe case in Embodiment 1 of the present invention, showing the tip of the needle;

[0080] Fig. 4-6 are schematic views of annular end surfaces of various shapes in various examples of the syringe case in Embodiment 1 of the present invention;

[0081] Fig. 7 is a schematic view of a projection formed by a syringe case and an eye tissue, and also illustrates the injection administration in Embodiment 1 of the present invention;

[0082] Fig. 8 is a schematic view of needles of various specifications used in the syringe case in Embodiment 1 of the present invention;

[0083] Fig. 9 schematically illustrates the connection of the syringe case in Embodiment 2 of the present invention;

[0084] Fig. 10 is a schematic view of a positioning cylinder of a syringe case in Embodiment 2 of the present invention;

[0085] Fig. 11 schematically illustrates the use of the syringe case in Embodiment 2 of the present invention;

[0086] Fig. 12 is a schematic view of a syringe used in embodiments of the present invention;

[0087] Fig. 13-15 are schematic views of restriction structures of various shapes used in various examples of the syringe case in Embodiment 2 of the present invention;

[0088] Fig. 16 is a schematic cross-sectional view of a connecting cylinder of a syringe case in Embodiment 2 of the present invention;

[0089] Fig. 17 is a partial sectional view of a syringe case in Embodiment 2 of the present invention;

[0090] Fig. 18 is a combined diagram of a syringe case in Embodiment 3 of the present invention;

[0091] Fig. 19 is a schematic exploded view of a syringe case in Embodiment 3 of the present invention;

[0092] Fig. 20 schematically illustrates the connection of the syringe case in Embodiment 4 of the present invention;

[0093] Fig. 21 is a combined diagram of a syringe case in Embodiment 5 of the present invention;

[0094] Fig. 22 is a schematic exploded view of a syringe case with a needle and a connecting barrel in Embodiment 6 of the present invention;

[0095] Fig. 23 is a schematic view of the connection of the needle and the connecting barrel in the first example of the syringe case with the needle and the connecting barrel in Embodiment 6 of the present invention;

[0096] Fig. 24 is a schematic view of the connection of the second example of the syringe case with the needle and the connecting barrel in Embodiment 6 of the present invention;

[0097] Fig. 25 is a schematic view of the connection of a third example of a syringe case with a needle and a connecting barrel in Embodiment 6 of the present invention;

[0098] Fig. 26 shows a section of the fundus tissue in Test Example 1 of the present invention;

[0099] Fig. 27 shows a section of the fundus tissue in Test Example 4 of the present invention;

[0100] Fig. 28 shows a section of the fundus tissue in Test Example 5 of the present invention;

[0101] Fig. 29 shows a section of the fundus tissue in Test Example 6 of the present invention;

[0102] Fig. 30 shows a section of the fundus tissue in Test Example 7 of the present invention;

[0103] Fig. 31 shows a section of the fundus tissue in Test Example 8 of the present invention.

[0104] Legend: 1 - Connecting cylinder; 11 - Injection end; 111 - Annular projection; 112 - Clamping hole; 113 - Cavity; 114 - Annular end surface; 115 - Tapering part; 12 - Connecting end; 13 - Positioning groove; 2 - Positioning cylinder; 21 - Mounting groove; 22 - Locking projection; 23 - Flange installation platform; 24 - Limiting structure; 25 - Limiting flange; 26 - Arc-shaped projection; 3 - Needle; 31 - Raised rib; 32 - Projection; 33 - Connector; 34 - Needle rod; 4 - Syringe; 41 - Syringe barrel flange; 5 - Luer connector.

[0105] DETAILED DESCRIPTION

[0106] The technical idea of ​​the present invention is described in detail with reference to test examples and specific embodiments. However, the scope of the above-mentioned subject matter of the present invention is not limited to the following embodiments; and all technical solutions implemented based on the content of the present invention fall within the scope of the present invention.

[0107] The contents of the present applicant's previous application PCT / CN2022 / 107104, entitled "Ophthalmic Injection Unit, Injection Device, and Method of Use Therefor," are incorporated into this application as part of the present invention. The injection site, needle specification, effective needle length, blade length, and blade penetration force are further explained as follows.

[0108] 1. Injection site

[0109] The injection site described here refers to any area of ​​the mucous membrane, such as the upper nasal area, the lower nasal area, the upper temporal area, or the lower temporal area.

[0110] The injection site can be located anywhere in any area of ​​the mucous membrane between the edge of the iris and the edge of the cornea, such as the superior nasal region, inferior nasal region, superior temporal region, or inferior temporal region, at a distance of approximately 3-9 mm, approximately 4-8 mm, approximately 4-7 mm, approximately 6-8 mm, approximately 7-8 mm, or approximately 4-5 mm from the edge of the cornea. The distance from the edge of the cornea can be approximately 3 mm, or approximately 4 mm, or approximately 5 mm, or approximately 6 mm, or approximately 7 mm, or approximately 8 mm.

[0111] 2. Needle specifications: You can choose existing commercial injection needles such as 28G, 30G, 31G, 32G, 33G and 34G, or use customized injection needles manufactured using the existing injection needle manufacturing method.

[0112] Needle technical parameters: The tip of the needle is usually sharp, beveled, or otherwise shaped to allow the needle to penetrate the ocular surface (e.g., the sclera). The needle used can have any suitable gauge, such as approximately 25G, approximately 26G, approximately 27G, approximately 28G, approximately 29G, approximately 30G, approximately 31G, approximately 32G, approximately 33G, approximately 34G, approximately 35G, or approximately 36G. The needle wall can have any suitable thickness. For example, in addition to the existing wall thickness (RW), the needle wall can be designed as thin wall (TW), extra / ultra thin wall (XTW / UTW), or extra thin wall (XXTW). These designations are well known to those skilled in the art. For example, the needle can be a cannula or a fine gauge needle. In some embodiments, the needle may have a gauge of 25G to 36G. In other embodiments, the needle may have a gauge of 27G to 35G.In other variations, the needle may have a gauge from 30G to 33G.

[0113] Effective needle length:

[0114] The effective length of the needle is the length extending from the clamping hole of the injection end of the connecting cylinder, and is approximately 1400 μm or less, approximately 1300 μm or less, approximately 1200 μm or less, approximately 1100 μm or less, approximately 1000 μm or less, approximately 900 μm or less, approximately 800 μm or less, approximately 850 μm or less, approximately 700 μm or less, approximately 650 μm or less, approximately 500 μm or less, or approximately 450 μm or less. In some embodiments, the effective length of the needle may be approximately 700 μm. In other embodiments, the effective length of the needle may be approximately 750 μm, or approximately 800 μm, or approximately 850 μm, or approximately 900 μm, or approximately 950 μm, or approximately 1000 μm, or approximately 1100 μm, or approximately 1350 μm.

[0115] Blade Length:

[0116] The blade length is the linear distance from the proximal inner edge of the needle wall at the liquid outlet of the needle tip to the edge of the tip of the outer wall of the liquid outlet of the needle tip and is approximately 800 μm or less, approximately 700 μm or less, approximately 650 μm or less, approximately 600 μm or less, approximately 550 μm or less, approximately 500 μm or less, approximately 450 μm or less, approximately 400 μm or less, approximately 350 μm or less, approximately 300 μm or less, or approximately 250 μm or less. In some embodiments, the blade length may be approximately 550 μm; in other embodiments, the blade length may be approximately 700 μm, or approximately 650 μm, or approximately 600 μm, or approximately 500 μm, or approximately 450 μm, or approximately 300 μm, or approximately 250 μm.

[0117] Blade penetration power:

[0118] The penetration force of the blade at the liquid outlet at the needle tip is approximately 0.7 N or less, approximately 0.65 N or less, approximately 0.5 N or less, approximately 0.4 N or less, or approximately 0.3 N or less, to achieve the desired position in the target tissue (e.g., the suprachoroidal space and / or vitreous body) and form a drug solution delivery channel. In some embodiments, the penetration force of the blade may be approximately 0.5 N; in other embodiments, the penetration force of the blade may be approximately 0.7 N or approximately 0.65 N or approximately 0.4 N or approximately 0.3 N.

[0119] Needle shaft length:

[0120] The needle shaft length is the length of the needle extending from the upper end surfaces of the raised ribs of the connector, and is approximately 10 mm or less, approximately 9 mm or less, approximately 8 mm or less, approximately 7 mm or less, approximately 6 mm or less, approximately 5 mm or less, approximately 4 mm or less, or approximately 3 mm or less. In some embodiments, the needle shaft length may be approximately 6.5 mm. In other embodiments, the needle shaft length may be approximately 6.9 mm, or approximately 7.0 mm, or approximately 7.5 mm, or approximately 7.8 mm, or approximately 8.0 mm, or approximately 8.2 mm.

[0121] 3. rAAV-anti-VEGF

[0122] In this document, the term “rAAV-anti-VEGF” means that the rAAV contains a VEGF antagonist expressed for the treatment of ocular diseases, and the VEGF antagonist is preferably Aflibercept, Conbercept, Ranibizumab or Bevacizumab.

[0123] Furthermore, the term "syringe," as used herein, has the definition commonly understood in the art and may include a barrel and a push rod, with the barrel having at least a flange to facilitate operator grip. The "syringe" may be pre-fitted with a needle, or the operator may select a needle suitable for injection into the patient.

[0124] Execution Option 1

[0125] As shown in Fig. 1 and 3, this embodiment provides a syringe case. The syringe case includes a connecting cylinder 1 and a positioning cylinder 2, both of which have a cylindrical structure, wherein the positioning cylinder 2 is used to be mounted outside the syringe 4 (Fig. 11); the two ends of the connecting cylinder 1 are respectively an injection end 11 and a connecting end 12, wherein the injection end 11 has an annular projection 111 and a clamping hole 112; as shown in Fig. 1, Fig. 3 and Fig. 15-17, which are described below, the annular projection 111 is a structure similar to a step around the inner side of the injection end 11, wherein the annular projection 111 is used to clamp the connector 33 of the needle 3 to limit the position of the needle 3. As shown in Fig.2, since the connector 33 of the needle 3 has raised ribs 31 and is clamped on the annular projection 111 by these ribs 31, the connector 33 cannot extend from the injection end 11. Therefore, by means of the projection 111, the injection end 11 of the connecting cylinder 1 can limit the length of the needle 3 protruding from the connecting cylinder 1, thereby limiting the length of the open tip of the needle 3 to the required range to meet the injection requirements for the tip of the needle 3. Thus, during the injection, the tip of the needle 3 can easily reach the sclera in the tissues of the eye, and the needle is suitable for injection into the target tissue of the eye.

[0126] In this embodiment, the upper end of the positioning cylinder 2 is the end facing the tail of the pusher (installed) of the syringe 4, and the lower end of the positioning cylinder 2 is the end facing the connecting cylinder 1. The outer diameter of the connecting end 12 of the connecting cylinder 1 corresponds to the inner diameter of the lower end of the positioning cylinder 2, and the connecting end 12 of the connecting cylinder 1 is inserted into the positioning cylinder 2 and connected to it from its lower end. The connecting end 12 of the connecting cylinder 1 has an external thread, and the inner wall of the lower end of the positioning cylinder 2 has an internal thread; by means of a threaded connection, the connecting end 12 can be connected to the positioning cylinder 2, and the total length of the cylinders 1 and 2 can be adjusted by rotation.When the connecting end 12 of connecting cylinder 1 rotates toward the end of the thread, cylinders 1 and 2 are connected in the final state and cannot rotate any further. At this point, the tip of needle 3 protrudes from the injection end 11 of connecting cylinder 1 to a predetermined length.

[0127] Next, let us consider Fig. 2. In this embodiment, on the periphery of the upper end of the connector 33 of the needle 3, there are three raised ribs 31, which are evenly distributed along the periphery of the connector 33; The raised ribs 31 form ridges distributed longitudinally along the periphery of the connector 33 in the direction of the needle shaft 34, so that the outer diameter of the upper end of the connector 33 is larger than the annular projection 111. The raised ribs 31 can be clamped or abut against the annular projection 111, and the length of the needle 3 protruding from the injection end 11 can be limited by the annular projection 111. The raised ribs 31 facilitate the clamping of the connector 33 in the injection end 11 of the connecting cylinder 1, so that the length of the needle shaft 34 minus the distance from the annular projection 111 to the clamping hole 112 is the length of the open tip of the needle 3. During use, as soon as the ribs 31 are clamped on the annular projection 111, the needle 3 reaches the end position and will no longer protrude outward.Thus, by precisely setting the positions of the needle shaft and the annular projection 111, it is possible to ensure that the tip of the needle 3 is extended only by a predetermined length to meet the requirements of injection into the eye tissue. Moreover, when the cylinders 1 and 2, rigidly connected by the syringe barrel, are rotated and tightened, the connecting cylinder 1 rests against the flange 41 of the syringe barrel, and the ribs 31 of the needle 3 are clamped in the annular projection 111. Thus, by precisely designing the positions of the flange 41 of the syringe barrel and the annular projection 111, the length of the open tip of the needle 3 can be adjusted, and the needle can be limited by cylinders 1 and 2, and the connector 33 can be quickly connected to the syringe in the positioning cylinder 2 into a single injection device, and the syringe 4 can lock the connector 33.From the above description, it can be seen that when using the syringe case proposed in this embodiment, there is no need to re-measure and confirm the penetration length and the position of the needle penetrating the eye tissue before injection, thereby saving time and labor, and no inaccurate dosage will occur during injection due to the reverse movement of the needle toward the syringe or the deviation of the needle from the injection site under the influence of the eye tissue at the injection site during injection into the eye.

[0128] In the process of the operator applying traction force to the syringe pusher to move the pusher in the syringe, since the connecting cylinder 1 locks the connector 33 of the needle, the tip of the needle 3 will not move along with the movement of the pusher, thereby avoiding injury to the target eye tissue or penetration through the target eye tissue due to excessive extension of the needle in the target eye tissue.

[0129] Next, let us consider Fig. 3. In this embodiment, the injection end 11 of the connecting cylinder 1 is the end facing the eye tissue and is used to allow the tip of the needle 3 to be extended for performing an injection operation. The tip of the injection end 11 of the connecting cylinder 1, i.e., the end of the connecting cylinder 1 facing the eye tissue, has a clamping hole 112, which is a round hole for pressing the eye tissue at the injection site. The clamping hole 112 has an annular end surface 114, which is the end surface of the injection end 11 and is annular. The annular end surface 114 has an inner annular curve and an outer annular curve with a certain distance between them. Both the inner annular curve and the outer annular curve are smooth transition curves, and the space surrounded by the inner annular curve is the clamping hole 112.The shortest line segment that passes through the injection point and has two ends located in the curve of the inner ring, i.e. the minimum inner diameter of the annular end surface of the clamping hole, is also called the inner diameter of the clamping hole. The portion between the inner annular curve and the outer annular curve is the wall thickness of the injection end 11. In this embodiment, the clamping hole 112 is a round hole, and the annular end surface 114 is shown in Fig. 4. In other embodiments, an elliptical annular end surface, as shown in Fig. 5, or a polygonal annular end surface, as shown in Fig. 6, can be used. Clamping holes of various shapes can be used to compress the eye tissue, such as a round shape, an elliptical shape, a hexagonal shape, an octagonal shape, a square shape, or an irregular shape.The annular end surface 114 is preferably an end surface with a ring shape, which is not only more favorable for preventing injury to the mucous membrane, but also more favorable for the recovery of eye tissue during injection.

[0130] During use, as shown in Fig. 7, the round edge of the clamping hole 112 contacts and presses against the ocular tissue. In this position, the ocular tissue protrudes into the injection end 11 in the clamping hole 112. At this time, the tip of the needle 3 penetrates the target ocular tissue at the injection site. By clamping an appropriate amount of ocular tissue with the clamping hole 112 and making the ocular tissue clearly protrude in the clamping hole 112, the medicinal solution can be successfully delivered to the target site, the injection success rate can be improved, reflux can be effectively prevented, and the diffusion of the medicinal solution under the mucous membrane can be prevented.

[0131] As shown in Fig. 3, in this embodiment, the injection end 11 further has a cavity 113, which is located in the injection end 11 near the clamping hole 112. The cavity 113 is cylindrical, and one end of the cavity 113 is closed by a connector 33, that is, the connector 33 abuts against the cavity 113 and separates the cavity 113 from the connecting tube 1, and the other end of the cavity 113 is closed by pressing the clamping hole 112 onto the eye tissues. With this arrangement of the cavity 113, when reflux occurs, the drug solution in the reflux will be contained in the closed cavity 113; when the clamping hole 112 is separated from the eye tissues, the drug solution will be absorbed by the cavity 113 by the siphon effect and will not easily flow out of the closed cavity 113, thus preventing the drug solution from entering the eye tissues.

[0132] In this embodiment, the injection end is made of a transparent material such as polypropylene, allowing the operator to conveniently observe the reflux of the drug solution and quickly judge the success of the injection. Alternatively, a viewing window made of a transparent material can be provided in the side wall of the injection end. The viewing window can also achieve convenient observation. The transparent injection end or transparent window can be further provided with scale lines, which are more conducive to accurately assessing the reflux of the drug solution and observing the reflux volume of the drug solution, thereby conveniently calculating the amount of drug solution injected.

[0133] The needle 3 is available in various specifications, and the syringe 4 can use 3 needles of different specifications to meet injection requirements. The needle shaft 34 and the 3 needles of different specifications have different lengths in the range of 5-10 mm. In this embodiment, the length of the needle shaft 34 can be selected from 6.7 mm, 6.9 mm, 7.1 mm, 7.5 mm, 7.8 mm, 8.0 mm, 8.2 mm, and 8.5 mm, etc. The needles 3 with the shaft 34 of different lengths can be individually selected according to different situations and the needs of different patients.

[0134] Execution Option 2

[0135] As shown in Figs. 9-10 and 12-17, this embodiment provides a syringe case. The structure of the syringe case is essentially the same as that of Embodiment 1, except for the following differences: in this embodiment, the connecting cylinder 1 has a positioning groove 13, and the positioning cylinder 2 has an installation groove 21 for installing the flange 41 of the syringe barrel. The installation groove 21 is a gap formed between the locking projection 22 and the platform 23 for installing the flange. The outer side of the positioning cylinder 2 additionally has a limiting structure 24. Using a syringe case, the flange 41 of the syringe barrel can be fixed to the positioning cylinder 2 by means of the structure of the existing syringe, so that the operation of the operator gripping the syringe 4 can be replaced by the operation of the operator gripping the syringe case, thereby making the use and operation more convenient.The total length of the cylinders 1 and 2 can be conveniently adjusted by the connection between the cylinders 1 and 2, so that the length of the open tip of the needle 3 can be adjusted by adjusting the relative position of the cylinders 1 and 2, so that the tip of the needle 3 is located in a desired position, and the length of the open tip of the needle 3 can meet the requirements of injection into the eye tissue.

[0136] As shown in Fig. 9, in this embodiment, the outer diameter of the connecting end 12 of the connecting cylinder 1 is the same as the inner diameter of the positioning cylinder 2, and the connecting cylinder 1 is inserted into the positioning cylinder 2 from the end of the cylinder 2 facing the tail of the syringe pusher 4 (the upper end of the positioning cylinder 2 in Fig. 9) to connect, that is, after the cylinders 1 and 2 enter a coaxial state, the injection end 11 of the connecting cylinder 1 is inserted into the positioning cylinder 2 from the end of the positioning cylinder 2 facing the tail of the syringe pusher 4. After insertion, the injection end 11 of the connecting cylinder 1 protrudes from the other end of the positioning cylinder 2 (the lower end of the positioning cylinder 2 in Fig. 9). The connecting end 12 of the connecting cylinder 1 has an external thread, and the inner wall of the positioning cylinder 2 has an internal thread.The end with the internal thread is spaced from the other end of the positioning cylinder 2, so that the external thread of the connecting cylinder 1 always corresponds to the internal thread of the positioning cylinder 2 when the connecting cylinder 1 is rotated to maintain the connection, and the connecting cylinder 1 will not be disconnected from the positioning cylinder 2. The connecting end 12 is connected to the positioning cylinder 2 by rotation, wherein the total length of the cylinders 1 and 2 is adjusted by rotation, and the relative length of the cylinders 1 and 2 can be adjusted by means of a threaded connection, thereby the total length can be adjusted. After installing the syringe 4 on the syringe case, the flange 41 of the syringe barrel rests against the connecting end 12 and limits the distance of the rear rotational movement of the connecting end 12 in the positioning cylinder 2.The syringe 4 can be integrated with the positioning cylinder 2, and the position of the connecting end 12 of the connecting cylinder 1 in the positioning cylinder 2 can be adjusted. The final position of the backward movement of the connecting end 12 is the position in which the tip of the connecting end 12 rests against the flange 41. At this time, the connecting end 12 can no longer move backward, thereby implementing the function of preventing the backward movement of the connecting cylinder.

[0137] As shown in Fig. 10-12, in this embodiment, the positioning cylinder 2 has a locking projection 22, a flange mounting platform 23 and a limiting structure 24; the upper end of the positioning cylinder 2 is the end of the positioning cylinder 2 facing the tail of the syringe pusher 4 after installing the syringe 4, and the lower end of the positioning cylinder 2 is the end of the positioning cylinder 2 facing the connecting cylinder 1 after connecting the positioning cylinder 2 with the connecting cylinder 1. The upper end of the positioning cylinder 2 is provided with a platform 23 for installing a flange, which is a platform for installing a flange 41 and is used to support one side of the flange 41. The upper end of the positioning cylinder 2 is connected to a locking protrusion 22 for clamping the other side of the flange 41. The locking protrusion 22 consists of two structures symmetrically located on the upper end of the positioning cylinder 2.The locking projection 22 has the shape of the Arabic numeral 7, and its lower end is connected to two sides of the platform 23 for installing the flange of the positioning cylinder 2. Two locking projections 22 are located opposite each other with a gap between them; the gap is used to allow the flange 41 of the syringe barrel to pass through it in the vertical direction when the syringe 4 is rotated, so that the flange 41 is clamped in the corresponding horizontal position of the mounting groove 21. Between the locking projection 22 and the platform 23 there is a gap, and the gap is also the mounting groove 21. After the flange 41 is positioned in accordance with the mounting groove 21 in the horizontal position, the flange 41 is rotated and clamped in the mounting groove 21 in the horizontal direction. The mounting groove 21 provides space for clamping the flange 41 on the positioning cylinder 2, so that the syringe 4 can be conveniently fixed on the cylinder 2.In this embodiment, the lower portion of the locking projection 22 has an arcuate projection 26, or the upper portion of the platform 23 has an arcuate projection 26 for fixing one side of the flange 41. When the arcuate projection 26 is located, the distance from the corresponding position of the projection 26 of the locking projection 22 to the platform 23 is less than the thickness of the flange 41, i.e. there is an interference fit between the flange 41, the locking projection 22 and the platform 23. With the arcuate projection 26 present, the flange 41 is clamped and fixed in the mounting groove 21, wherein the flange 41 is in a locked state after being clamped in order to prevent the syringe 4 from being disconnected from the positioning cylinder 2.

[0138] In this embodiment, the positioning cylinder 2 has a limiting structure 24, which is located on its outer side. As shown in Fig. 11, the limiting structure 24 can be a ring structure, which is located on one side of the positioning cylinder 2 and is used to clamp the operator's fingers. The ring structure makes it convenient to place the fingers. During use, the operator extends the index finger or another finger and fixes it in the ring structure, so that the operator can comfortably hold the syringe case and fix the finger relative to the syringe case to facilitate operation. Alternatively, the limiting structure 24 can be a protrusion or a recess, as shown in Figs. 13-15.

[0139] As shown in Fig. 16 and 17, in this embodiment, the connecting cylinder 1 further has two positioning grooves 13 located in opposite positions, or may have one or more positioning grooves 13. The positioning groove 13 is formed by the inner wall of the connecting cylinder 1, recessed in the axial direction, thus, two positioning grooves 13, having the same length and located in opposite positions, are formed in the inner wall of the connecting cylinder 1. The positioning groove 13 is used for clamping with the outer side of the connector 33 of the needle 3, or the outer side of the syringe barrel can be made in a shape corresponding to the positioning groove 13.In this embodiment, projections 32 are formed on the outer sides of the connector 33, wherein the shape and size of the projections 32 correspond to the cross-section of the positioning groove 13; that is, the projections 32 are formed on two sides of the connector 33, wherein the two projections 32 limit the needle 3 in the positioning groove 13, so that the needle 3 can move in the axial direction in the connecting cylinder 1 along the positioning groove 13. When the projections 32 move along the positioning groove 13, the needle 3 can be released from the positioning groove 13 and rotate relative to the connecting cylinder 1. Thus, when the syringe 4 is inserted, the syringe 4 always moves in one direction under the direction of the needle 3 without oscillation, thus the needle 3 will not come into contact with the inner wall of the connecting cylinder 1 during the insertion of the syringe 4 and will be maintained in a clean state.

[0140] Execution Option 3

[0141] As shown in Fig. 18-19, this embodiment provides a syringe case. The structure of the syringe case in this embodiment is essentially the same as that of Embodiment 1, except for the following differences: the connecting cylinder 1 is connected to the end of the positioning cylinder 2 facing the needle 3, that is, the connecting end 12 of the connecting cylinder 1 abuts the lower end of the positioning cylinder 2 in opposite directions.

[0142] As shown in Fig. 19, in this embodiment, the injection end 11, the positioning groove 13 and the structure of the connecting cylinder 1 are the same as those of embodiment 1, but the length of the connecting cylinder 1 is shorter than that of embodiment 1. The lower end of the positioning cylinder 2 in this embodiment has an extension, and the overall length of the positioning cylinder 2 is longer than that of embodiment 1. The connecting end 12 of the connecting cylinder 1 has an internal thread, and the extension at the lower end of the positioning cylinder 2 has an external thread. The inner diameter of the connecting end 12 of the connecting cylinder 1 corresponds to the outer diameter of the extension of the positioning cylinder 2, and the cylinders 1 and 2 can be connected by means of a thread.During the connection, when the connecting cylinder 1 is rotated toward the upper end of the threaded extension, the tip of the connecting end 12 of the connecting cylinder 1 properly rests against the upper end of the extension of the positioning cylinder 2; at this time, the total length of the cylinders 1 and 2 will no longer decrease, and the position is the final position of the connection. When used, the syringe 4 is first placed in the positioning cylinder 2, and the flange 41 is clamped in the mounting groove 21 of the positioning cylinder 2 for fixation. At this time, the syringe 4 is partially pulled out of the positioning cylinder 2; then the connecting cylinder 1 is inserted from one end of the needle 3 of the syringe 4, so that the needle 3 of the syringe 4 is located on the injection end 11 of the connecting cylinder 1; then the connecting cylinder 1 is rotated and connected to the positioning cylinder 2.When the connecting cylinder 1 is rotated to the final position, the length of the protruding tip of the needle 3 exactly corresponds to the specified length for injection into the eye tissue and meets the requirements of injection into the eye tissue.

[0143] Execution Option 4

[0144] This embodiment provides a syringe case. The structure of the syringe case in this embodiment is essentially the same as that of Embodiment 3, except for the following differences: The connecting cylinder 1 is connected to the positioning cylinder 2 via a snap connection.

[0145] As shown in Fig. 20, in this embodiment, the structures of the injection end 11 of the connecting cylinder 1, the positioning groove 13, and the positioning cylinder 2 are the same as in Embodiment 3, but the connecting end 12 of the connecting cylinder 1 has a fastening member, and the inner side of the lower end of the positioning cylinder 2 has a groove corresponding to this fastening member. The outer diameter of the connecting end 12 of the connecting cylinder 1 is equal to the inner diameter of the lower end of the positioning cylinder 2, so that the connecting end 12 of the connecting cylinder 1 can be snapped with the positioning cylinder 2 by inserting into the positioning cylinder 2.More specifically, the connecting end 12 of the connecting cylinder 1 has fastening elements on both sides, wherein the fastening elements protrude outward from both sides of the connecting end 12, and the grooves in the inner wall of the lower end of the positioning cylinder 2 correspond to the fastening elements in shape and size; during use, the syringe 4 is first placed in the positioning cylinder 2, and the flange 41 of the syringe barrel is clamped in the mounting groove 21 of the positioning cylinder 2 and fixed there; at this point, the syringe 4 is partially pulled out of the positioning cylinder 2. Then, the connecting cylinder 1 is put on the syringe 4 from the end of the syringe 4 with the needle 3 so that the needle 3 is located on the injection end 11 of the connecting cylinder 1, and then the cylinders 1 and 2 are joined. When the connecting cylinder 1 is inserted into the positioning cylinder 2 to the end position, the fastening element snaps into the groove.At this point, the length of the open tip of needle 3 corresponds to the specified injection length for injection into the eye tissue and meets the requirements of injection into the eye tissue.

[0146] Execution Option 5

[0147] This embodiment provides a syringe case. In this embodiment, only the connecting cylinder 1 is the same as the connecting cylinder in Embodiment 2, and the positioning cylinder 2 has only the mounting groove 21 but does not have the limiting structure 24.

[0148] As shown in Fig. 21, in this embodiment, the two ends of the connecting cylinder 1 are, respectively, an injection end 11 and a connecting end 12. The connecting end 12 of the connecting cylinder 1 has an external thread, the lower end of the positioning cylinder 2 has an internal thread, and the connecting end 12 of the connecting cylinder 1 is connected to the positioning cylinder 2 by a threaded connection. The upper end of the positioning cylinder 2 further has a mounting groove 21 for mounting the flange 41 of the syringe barrel. The mounting groove 21 is formed by the upper end of the positioning cylinder 2 in the form of a recess on the outer side, so that the flange 41 can be clamped in the mounting groove 21.The injection end 11 of the connecting cylinder 1 has a tapered portion 115, the cross-sectional area of ​​which gradually increases in the direction from the clamping hole 112 of the injection end 11, wherein the inner opening of the tapered portion 115 is smaller than the upper end of the connector 33, so that the connector 33 of the needle 3 of the syringe 4 can be clamped and limited from further movement, thereby achieving the function of limiting the needle. The injection end 11 allows the shaft of the needle 3 to pass through it, so that after connecting the connecting cylinder 1 with the positioning cylinder 2, the tip of the needle 3 can be opened at the injection end 11 of the connecting cylinder 1. The syringe case can replace the initial operation of gripping the syringe 4 by the operator with the operation of gripping the syringe case by the operator, thereby making the use and operation more convenient.The total length of the cylinders 1 and 2 can be conveniently adjusted by the connection between them, so that the length of the open tip of the needle 3 can be adjusted by adjusting the relative positions of the cylinders 1 and 2, so that the tip of the needle 3 is positioned, and the length of the open tip of the needle 3 can meet the requirements of injection into the eye tissue.

[0149] When cylinders 1 and 2 adjust the open tip length of needle 3 and limit needle 3, syringe 4 can block connector 33. There is no need to measure and confirm again during use, thereby greatly saving time and labor, and during injection, inaccurate dosage will not occur due to the needle moving backward toward the syringe or the needle deviating from the injection position under the influence of tissue at the injection site during the injection process.

[0150] In the process, when the operator applies a pulling force to the syringe pusher to move the pusher in the syringe, since the syringe blocks the 33 needle connector, the needle tip will not move along with the movement of the pusher, thereby avoiding injury to the target eye tissue or penetration through the target eye tissue due to excessive extension of the needle in the target eye tissue.

[0151] Execution Option 6

[0152] As shown in Fig. 22-25, this embodiment provides a case (for a syringe) with a needle. The case for a syringe includes the following components that are put on the outside of the syringe: a connecting cylinder 1 and a positioning cylinder 2. Cylinders 1 and 2 in this embodiment have the same structure as those in Embodiment 2, except for the following differences: As shown in Fig. 22, cylinders 1 and 2 are indirectly connected by a Luer connector 5, and the connecting cylinder 1 and the needle 3 are connected by a thread, limiting structures 24 are located on both sides of the positioning cylinder, and the connecting end 12 of the connecting cylinder 1 is connected to the connector 33 of the needle 3. The total length of the connecting end 12 of the connecting cylinder 1 and the connector 33 can be adjusted.The total length from the connecting end 12 of the connecting cylinder 1 to the connector 33 can be changed at least once from the initial position and connection state to the final position and connection state, thus the total length of the connecting cylinder 1 and the connector 33 can be changed.

[0153] As shown in Fig. 23, in this embodiment, the inner wall of the connecting end 12 of the connecting cylinder 1 has an internal thread portion in the axial direction, while the outer side of the connector 33 has an external thread corresponding to the connecting end 12. When the connector 33 and the connecting cylinder 1 are rotated and tightened in a forward direction, the tip of the needle 3 protrudes from the injection end 11 of the connecting cylinder 1, and the protruding length can properly meet the requirements of injection into the ocular tissue. The connection between the positioning cylinder 2 and the flange 41 is the same as that in Embodiment 2, and the syringe barrel is clamped in the installation groove for fixation. After the positioning cylinder 2 and the syringe barrel are firmly connected, the syringe and the connector 33 are quickly connected via the Luer connector 5 of the syringe 4, forming a single injection device.The syringe case is indirectly connected to the connecting cylinder 1 via the needle 3, and the open end length of the needle 3 is limited by the injection end 11. This allows the tip of the needle 3 to be positioned to meet the requirements of ocular tissue injection. Furthermore, the connection and adjustment of the needle 3 and the connecting cylinder 1 can be completed quickly, eliminating the need for repeated measurements and confirmations during use, thereby significantly saving time and labor.

[0154] As shown in Fig. 24, the lower end of the positioning cylinder 2 has a limiting flange 25. When the connector 33 and the connecting cylinder 1 are rotated and tightened, the connecting cylinder 1 moves toward the Luer connector 5 on the injection end of the syringe until it rests against the limiting flange 25 of the positioning cylinder 2, thus the reverse movement of the connecting cylinder 1 can be prevented. At this moment, the raised ribs 31 of the needle 3 are clamped on the annular projection 111. By precisely designing the positions of the limiting flange 25 and the annular projection 111, it is ensured that the connector 33 can be quickly connected to the Luer connector 5 to form a single injection device, and the Luer connector 5 can lock the connector 33, while the length of the open tip of the needle 3 is limited by the injection end 11.

[0155] Therefore, there is no need to repeat the measurement and confirmation during use, which can greatly save time and labor, and during injection, inaccurate dosage will not occur due to the needle moving backwards toward the syringe or the needle deviating from the injection position under the influence of tissues at the injection site during the injection process.

[0156] In the process of the operator applying traction force to the syringe pusher to move the pusher in the syringe, since the syringe blocks the needle connector 33, the needle tip will not move along with the movement of the pusher, thereby avoiding injury to the target eye tissue or penetration through the target eye tissue due to excessive extension of the needle in the target eye tissue.

[0157] As shown in Fig. 25, in this embodiment, the outer wall of the positioning cylinder between the limiting flange 25 and the lower end of the positioning cylinder 2 has an external thread that can be aligned with the internal thread of the connecting cylinder 1. After the connector 33 is inserted into the connecting cylinder 1 from the connecting end 12 of this cylinder 1, the connecting end 12 is directly connected to the lower end of the positioning cylinder 2, which is rigidly connected to the syringe barrel.Cylinders 1 and 2 rotate relative to each other, so that connecting cylinder 1 moves toward the bottom of positioning cylinder 2, and the tip of needle 3 protrudes from injection end 11 of connecting cylinder 1 until connecting end 12 rests against limiting flange 25 of positioning cylinder 2 and can no longer move, and raised ribs 31 of needle 3 are clamped in annular projection 111, thus, the length of protruding tip of needle 3 can meet the requirements of injection into eye tissue, and syringe 4 fixes connector 33.

[0158] This eliminates the need for repeated measurement and confirmation during use, significantly saving time and labor. Inaccurate dosing during injection is prevented due to the needle moving backward toward the syringe or the needle being deflected from the injection site by tissue impact during injection. Furthermore, premature withdrawal of needle tip 3 from connecting cylinder 1 is prevented, which could increase the risk of operator injury or damage to the needle tip.

[0159] In the process, when the operator applies a pulling force to the syringe pusher to move the pusher in the syringe, since the syringe blocks the needle connector, the needle tip will not move along with the movement of the pusher, thereby avoiding injury to the target eye tissue or penetration through the target eye tissue due to excessive expansion of the needle in the target eye tissue.

[0160] In this embodiment, by selecting 3 needles of different specifications to connect with the connecting end 12 of the connecting cylinder 1, it is possible to meet the needs of people of different ages, as well as the needs of different patients with different actual parameters of ocular tissue thickness.

[0161] In this embodiment, the outer wall of the positioning cylinder between the limiting flange 25 and the lower end of the cylinder 2 can be connected to the connecting cylinder 1 by means of a thread or can be connected by an existing connection and fixing method such as a plug, snap-in or crimping.

[0162] Execution Option 7

[0163] In this embodiment, an injection unit is provided. The injection unit can use the syringe case shown in the 1st to 6th embodiments. For example, as shown in Fig. 11, the injection unit may include a syringe case, a syringe 4 and a needle 3, and the injection unit is an integrated structure in which the syringe 4 and the syringe case are assembled together. The syringe 4 is placed in the cylinders 1 and 2, and the flange 41 of the barrel of the syringe 4 is clamped in the mounting groove 21, thus, the syringe 4 is fixed on the positioning cylinder 2. By using the cylinders 1 and 2 or the connector 33 of the needle 3, the length of the needle 3 of the syringe 4 protruding from the connecting cylinder 1 can be adjusted, and finally, a predetermined length of the open portion of the needle 3 can be maintained.The injection unit can be combined with the syringe 4, thereby the length of the tip of the needle 3 can be conveniently adjusted to the required length and accuracy, so that the operator can more easily operate with one hand, and the use and operation become more convenient; moreover, when the cylinders 1 and 2 interact to adjust and limit the length of the open tip of the needle 3, the syringe 4 in the positioning cylinder 2 can be quickly connected to the connector 33 of the needle, forming an integral injection device, and the connector 33 is locked.

[0164] Therefore, there is no need to repeat the measurement and confirmation during use, which can greatly save time and labor, and during injection, inaccurate dosage will not occur due to the needle moving backwards toward the syringe or the needle deviating from the injection position under the influence of tissue at the injection site during the injection process.

[0165] In the process of the operator applying traction force to the syringe pusher to move the pusher in the syringe, since the syringe blocks the needle connector, the needle tip will not move along with the movement of the pusher, thereby avoiding injury to the target eye tissue or penetration through the target eye tissue due to excessive extension of the needle in the target eye tissue.

[0166] Option 8

[0167] This embodiment provides a method for using a syringe case. The method can use the syringe case shown in embodiments 1 through 5. If embodiment 2 is used, the method includes:

[0168] A1. First, insert the connecting cylinder 1 from the upper end of the positioning cylinder 2, and then insert the syringe 4 into the cylinders 1 and 2 from the upper end of the positioning cylinder 2 so that the syringe 4 is completely inserted under the guide of the positioning groove 13 of the connecting cylinder 1, and the needle 3 of the syringe 4 is at the injection end 11 of the connecting cylinder 1; then connect the cylinders 1 and 2 by means of a threaded connection by rotation.

[0169] A2. The connecting cylinder 1 is rotated further so that the flange 41 of the syringe barrel moves to a position corresponding to the installation groove 21 along with the rotation of the connecting cylinder 1, then the flange 41 of the barrel is moved by the connecting cylinder 1 so that it is clamped in the installation groove 21 for fixation during rotation, or manually clamped in the installation groove 21 for fixation; after the flange 41 is clamped, the syringe 4 is fixed on the positioning cylinder 2; at this time, the tip of the needle 3 is in the injection end 11 of the connecting cylinder 1 and is not open; the direction of rotation in steps A1 and A2 is set as the forward direction.

[0170] A3. The connecting cylinder 1 is rotated in the reverse direction, thereby the total length of the cylinders 1 and 2 gradually decreases, and the connecting end 12 of the connecting cylinder 1 moves backward. When the connecting end 12 of the connecting cylinder 1 abuts the surface of the flange 41, the tip of the connecting end 12 of the connecting cylinder 1 is limited by the flange 41, and the connecting cylinder 1 cannot move backward further, so that the cylinders 1 and 2 reach the end position. At this time, the connector 33 of the needle 3 is clamped by the annular projection 111, and the tip of the needle 3 protrudes from the injection end 11 of the connecting cylinder 1 by a predetermined length, so that the connector 33 abuts the syringe 4 and is fixed by the syringe, and the needle 3 cannot move backward further.By changing the rotation mode of the connecting cylinder 1, the connection between the cylinders 1 and 2 is divided into two stages: one stage is a rotational connection for connecting the cylinders 1 and 2; the other stage is a rotation in the opposite direction for adjusting the overall length of the cylinders 1 and 2, thereby adjusting the length of the open tip of the needle 3 and providing the syringe 4 in the positioning cylinder 2 with the ability to quickly connect with the needle 3 to form a single injection device and lock the connector 33.

[0171] If the syringe case of embodiment 3 is used, the method comprises: first, putting the positioning cylinder 2 on the outside of the syringe barrel 4; then clamping the flange 41 in the mounting groove 21 for fixation; then putting the connecting cylinder 1 on the outside of the syringe 4 so that the needle 3 of the syringe 4 is located at the injection end 11 of the connecting cylinder 1; and finally, inserting the connecting cylinder 1 into the lower end of the positioning cylinder 2 and directly connecting them by snapping. After forming the snap connection, the length of the open tip of the needle 3 corresponds to a predetermined length for injection into the eye tissue.

[0172] Option 9

[0173] This embodiment provides a method for using a syringe case. The method utilizes the syringe case with a needle provided in Embodiment 6, and the method includes:

[0174] A1. First, put the connecting end of the connecting cylinder 1 on the connector 33 of the needle 3; then connect the connector 33 using the Luer connector 5 or directly insert the connector 33 into the end of the pre-filled syringe installed in the positioning cylinder 2 near the needle; then connect the connecting end of the connecting cylinder 1 to the connector 33 using a threaded connection by rotation. The connecting cylinder 1 rotates and moves on the connector 33 in the direction of the needle 3, and the total length of the injection end of the connecting cylinder 1 and the connector 33 begins to gradually decrease, and the connecting end 12 of the connecting cylinder 1 moves backward. When the connecting end 12 of the connecting cylinder 1 rests against the base of the connector 33, the tip of the connecting end 12 of the connecting cylinder 1 is limited and clamped by the flange 41, and the connecting cylinder 1 cannot move backward further.At this moment, cylinders 1 and 2 reach the final position, whereby connector 33 is clamped by annular protrusion 111, the tip of needle 3 protrudes at injection end 11 of connecting cylinder 1, and the protruding length is equal to a given length.

[0175] A2. Insert the syringe barrel into the positioning cylinder 2 from the upper end of the cylinder 2; rotate the cylinder 2 so that the flange 41 moves to a position corresponding to the mounting groove 21 along with the rotation of the positioning cylinder 2, and then rotate the flange 41 and clamp it in the mounting groove 21 under the action of the drive of the cylinder 2, or manually clamp the flange 41 in the mounting groove 21 for fixation. After the flange 41 is clamped, the syringe 4 is fixed on the cylinder 2.

[0176] A3. Rotate the positioning cylinder 2 with the syringe barrel installed in it in the opposite direction relative to the connecting cylinder 1 and connect it to the outer wall of the connector 33; when the positioning cylinder 2 with the syringe barrel installed in it moves toward the Luer connector 5 of the syringe 4 in the opposite direction relative to the connecting cylinder 1, insert the distal end of the syringe barrel into the inner opening of the connector 33 until the connecting cylinder 1 rests against the limiting flange 25 of the positioning cylinder 2, so that the distal end of the syringe barrel, i.e. the end where the needle is installed on the syringe, locks the connector 33.

[0177] Execution Option 10

[0178] This embodiment provides a method for using an injection unit. Here, the injection unit provided in Embodiment 7 is used; in the example where the syringe case provided in Embodiment 1 is used, in the method:

[0179] B1. Install the drug suction needle at the distal end of the syringe barrel 4 and perform the drug suction operation;

[0180] B2. The needle 3 of a certain specification is selected and installed in the attachment point of the syringe needle 4 according to the requirements;

[0181] B3. Insert the connecting cylinder 1 into the positioning cylinder 2 to complete the initial connection, and then insert the syringe 4 with the needle 3 into the cylinders 1 and 2;

[0182] B4. Rotate the connecting cylinder 1 in the forward direction, so that the syringe 4 with the needle 3 is driven into rotation by the connecting cylinder 1, and the flange 41 of the syringe barrel is clamped in the installation groove 21, thus the syringe 4 and the positioning cylinder 2 are fixed together;

[0183] B5. Rotate the connecting cylinder 1 in the reverse direction to adjust the length of the tip of the needle 3 protruding from the connecting cylinder 1, adjusting the overall length of the connection between the cylinders 1 and 2, until the connecting cylinder 1 can no longer move backward; at this point, the length of the protruding tip of the needle 3 will be equal to the set length;

[0184] B6. Insert the finger into the limiting structure 24 so that the finger is fixed relative to the syringe case, and hold the syringe case in the same hand to perform the operation;

[0185] B7. Measure the eye to be injected and confirm the injection site with a measuring instrument;

[0186] B8. holding the syringe case, position the clamping hole 112 of the connecting cylinder 1 perpendicular to the surface of the eye tissue at the injection site;

[0187] B9. The clamping hole 112 of the connecting cylinder 1 is brought into contact with the eye tissue at the injection site by means of the interaction of the syringe 4 of the ocular injection device and the syringe case, and a force is applied to the eye tissue at the injection site so that the conjunctival tissue clamped by the clamping hole 112 of the connecting cylinder 1 protrudes into the injection end 11 of the cylinder 1, and the tip of the needle 3 is pressed into the target eye tissue at the injection site;

[0188] B10. Press the syringe pusher 4 with the same hand or with the other hand for injection so that the drug reaches the target tissue at the injection site.

[0189] In this method, three different needle specifications can be selected to meet the needs of different ages and patients with different ocular tissue thicknesses. The fingers can be fixed to the outside of the sheath using the limiting structure 24. The fingers can be conveniently fixed to the sheath, and the ocular tissue can be pressed and pressed through the clamping hole 112. Thus, the tip of the needle 3 can penetrate the target tissue, allowing the operator to conveniently inject the drug into the ocular tissue with one hand.

[0190] The method of use is explained in the test examples below. The contents of test examples 1 and 2 are also described in PCT / CN2022 / 107104.

[0191] Test Example 1

[0192] The test was numbered as Test No. 1-1. An eye injection unit and a syringe having the structure described in Embodiment 10 of PCT / CN2022 / 107104 were used to form an injection device. According to the normal tissue thickness of the sclera and choroid of New Zealand rabbits, a needle with an effective length of 700 μm and a blade length of 500±50 μm was used, and the clamping hole 112 of the connector was round and had an inner diameter of 1.5 mm;

[0193] The effective length, that is, the length of the tip of the needle 2 outside the clamping hole 112, was 700 μm; that is, the distance from the tip of the needle 2 to the annular end surface was 700 μm; the needle 2 was substantially perpendicular to the annular end surface;

[0194] Test method: After pentobarbital anesthesia, procaine hydrochloride eye drops were used to anesthetize the ocular surface, and injection into the suprachoroidal space was performed using an injection site within 1-2 minutes after instillation of the eye drops.

[0195] Test animals: healthy New Zealand rabbits, 1.8-2.2 kg;

[0196] Injection frequency: spot injection into the right eye;

[0197] Input reagent: 0.2% ICG, 100μl;

[0198] The injection method into the suprachoroidal space was as follows:

[0199] Step 1: Measure the distance with ophthalmic caliper to determine the injection site;

[0200] Step 2: sucking the injection reagent into the syringe and applying force to one side of the clamp hole 112 through the syringe so that the side of the clamp hole 112 adheres to the ocular tissue at the injection site, and a fulcrum is formed on the surface of the eye at the injection site;

[0201] Step 3: rotate the injection device around the fulcrum to the other side of the clamping hole 112 so that the distal end of the needle 3 penetrates the eye tissue at the injection site;

[0202] Step 4: rotate around the fulcrum further so that the other side of the clamp hole 112 tightly grips the surface of the eye at the injection site, and the clamp hole 112 holds the eye tissue, forming a bulge in the sheath 3, and the distal end of the needle 3 is vertically pressed into the sclera to reach the target eye tissue at the injection site; and

[0203] Step 5: Inject the drug into the injection site.

[0204] During the injection, injection results were recorded, including reflux, ocular surface diffusion, subconjunctival remnant, diffusion, bleeding, or congestion. The rabbit was then sacrificed, the eyes were dissected, flat fundus tissue samples were prepared, and the distribution of the ICG solution in the suprachoroidal space was recorded using photographs.

[0205] Test result: According to the observation results, there was no reflux or subconjunctival residue after ICG injection. The fundus tissue section result is shown in Fig. 26. All fundus tissues were transfected with ICG, and the stained fundus tissues were light green.

[0206] Test Example 2

[0207] Based on Test Example 1, the inner diameter of the clamping hole 112 was adjusted to study the effect of the inner diameter of the clamping hole 112 on the backflow of the drug solution, while other conditions were kept unchanged. The inner diameters of the clamping holes 112 were respectively 0.25 mm (Test No. 1-2), 0.5 mm (Test No. 1-3), 1.0 mm (Test No. 1-4), 2.0 mm (Test No. 1-5), 2.5 mm (Test No. 1-6), 3.0 mm (Test No. 1-7), 5.0 mm (Test No. 1-8) and 10.0 mm (Test No. 1-9).

[0208] Test Example 1 and Test Example 2 are summarized as follows:

[0209] Table 1 - Effect of different internal diameters of clamping holes 112 on reflux

[0210] Test number Connector inner diameter (mm) Experimental phenomena (right eye) Experimental phenomena (tissue section) 1-1 1,5 No reflux, no superficial or subconjunctival diffusion. All transfected with ICG, light green in color. 1-2 0,25 Obvious reflux and obvious diffusion on the ocular surface and under the mucous membrane The reflux was severe, and the injection failed. The rabbit was not sacrificed to make fundal cuts. 1-3 0,5 Obvious reflux and obvious diffusion on the ocular surface and under the mucous membrane The reflux was severe, and the injection failed. The rabbit was not sacrificed to make fundal cuts. 1-4 1,0 No reflux, no superficial or subconjunctival diffusion. The painted area is approximately 3 / 4, the color is green 1-5 2,0 There was no obvious reflux, there was no diffusion on the surface of the eye, there were traces of residue under the mucous membrane, but there was no diffusion. The painted area is more than 3 / 4, the color is dark green 1-6 2,5 There was no obvious reflux, there was no diffusion on the surface of the eye, there were traces of residue under the mucous membrane, but there was no diffusion. The painted area is approximately 2 / 3, the color is dark green 1-7 3,0 There was no obvious reflux, no diffusion on the surface of the eye, there were traces of residue and small bulges under the mucous membrane, but no diffusion The painted area is approximately 3 / 5, the color is dark green 1-8 5,0 No reflux, diffusion on the ocular surface, or submucosal debris The fundus tissue was not stained, but the vitreous body was stained 1-9 10,0 No reflux, diffusion on the ocular surface, or submucosal debris The fundus tissue was not stained, but the vitreous body was stained

[0211] The experimental result showed that when the inner diameter was 1-3mm, there was no obvious reflux or diffusion on the ocular surface or under the mucous membrane, and the tissue section result showed that the stained area was 3 / 5 to 3 / 4, and the injection was successful.

[0212] Test Example 3

[0213] Syringe: BD, disposable sterile syringe with needle, lot number: 300841.

[0214] Needle: 30G

[0215] Syringe case: case of embodiment 1

[0216] Introduced reagent and volume: 100 μL

[0217] Test steps:

[0218] 1. Ten syringes were used, each syringe was filled with 100 μL of purified water; an injection force of 10±2 N was used to simulate ocular injection. The syringe was weighed before and after injection, and the dosage and its relative standard deviation (RSD) were calculated.

[0219] 2. The syringe in step 1 was used, and 100 μL of purified water was again drawn into each syringe; each syringe was respectively loaded into the case described in Embodiment 1; after assembly, the injection fixation force described in step 1 was used to simulate injection into the eye; the syringe and the fixator were weighed before and after injection, and the dosage and its relative standard deviation (RSD) were calculated to study the effect of the syringe case proposed in the embodiments of the present invention on the accuracy of dosage administration.

[0220] Test result: With the existing dosage and its relative standard deviation (as shown in Table 2) before and after administration using the syringe case in the embodiments of the present invention, it was proved that the syringe case in the present invention can significantly improve the dosage accuracy.

[0221] Table 2. Dosage and its relative standard deviation (RSD) before and after administration using a syringe case

[0222] Group Syringe No. Before administration (g) After administration (g) Dosage (g) RSD (%) Without syringe case Syringe 1 3,3011 3,2131 0,0880 8,89 Syringe 2 3,3490 3,2370 0,1120 Syringe 3 3,3316 3,2278 0,1038 Syringe 4 3,3565 3,2556 0,1009 Syringe 5 3,3201 3,2142 0,1059 Syringe 6 3,3602 3,2782 0,0820 Syringe 7 3,3333 3,2276 0,1057 Syringe 8 3,3314 3,2286 0,1028 Syringe 9 3,3739 3,2694 0,1045 Syringe 10 3,3362 3,2338 0,1024 With a syringe case Syringe 1 10,8107 10,7172 0,0935 3,73 Syringe 2 10,8596 10,7592 0,1004 Syringe 3 10,8316 10,7397 0,0919 Syringe 4 10,8386 10,7382 0,1004 Syringe 5 10,8228 10,7231 0,0997 Syringe 6 10,8458 10,7481 0,0977 Syringe 7 10,8256 10,7219 0,1037 Syringe 8 10,8240 10,7218 0,1022 Syringe 9 10,8502 10,7531 0,0971 Syringe 10 10,8566 10,7591 0,0975

[0223] Test Example 4

[0224] The syringe connector and the syringe in Embodiment 1 were used to form an injection unit in which the inner diameter of the clamping hole 112 of the connecting cylinder 1 was 1.5 mm and the blade length was 450±50 μm.

[0225] Study method: After pentobarbital anesthesia, procaine hydrochloride eye drops were used to anesthetize the ocular surface, and injection into the suprachoroidal space was performed using a homemade injection device for 1-2 minutes after instillation of eye drops.

[0226] Experimental animals: healthy New Zealand rabbits, 1.8-2.2 kg;

[0227] Injection frequency: spot injection into the right eye;

[0228] Input reagent: 0.2% ICG, 100μl;

[0229] Injection method:

[0230] The method of injection into the suprachoroidal space is as follows:

[0231] Step 1: Insert the drug suction needle into the distal end of the syringe barrel 4, complete the drug suction operation, remove the drug suction needle and replace it with needle 3;

[0232] Step 2: first, inserting the connecting cylinder 1 from the upper end of the positioning cylinder 2, and then inserting the syringe 4 into the cylinders 1 and 2 from the upper end of the positioning cylinder 2 so that the syringe 4 is fully inserted under the guidance of the positioning groove 13 of the connecting cylinder 1, and the needle 3 of the syringe 4 is at the injection end 11 of the connecting cylinder 1; then connecting the cylinders 1 and 2 by means of a threaded connection by rotation;

[0233] Step 2: further rotating the connecting cylinder 1, so that the flange 41 moves to a position corresponding to the installation groove 21, together with the rotation of the connecting cylinder 1, then the flange 41 is driven to rotate by the cylinder 1 to be clamped in the installation groove 21 for fixation, or is manually clamped in the installation groove 21 for fixation; after the flange 41 is clamped, the syringe 4 is fixed on the positioning cylinder 2; at this time, the tip of the needle 3 is in the injection end 11 of the connecting cylinder 1 and is not open; the direction of rotation here is set as forward;

[0234] Step 3: Rotate the connecting cylinder 1 in the reverse direction, thereby gradually reducing the total length of the cylinders 1 and 2, and move the connecting end 12 of the connecting cylinder 1 backward. When the connecting end 12 of the connecting cylinder 1 abuts the surface of the flange 41, the tip of the connecting end 12 of the cylinder 1 is limited and clamped by the flange 41, and the cylinder 1 cannot move backward further, the syringe 4 locks the connector 33 of the needle 1, so that the cylinders 1 and 2 reach the end position. At this time, the connector 33 of the needle 3 is clamped by the annular projection 111, and the tip of the needle 3 protrudes from the injection end 11 of the connecting cylinder 1 by a predetermined length.By changing the rotation mode of the connecting cylinder 1, the connection between the cylinders 1 and 2 is divided into two stages: one stage is the rotational connection to complete the connection between the cylinders 1 and 2; the other state is the reverse rotation to adjust the total length of the cylinders 1 and 2, thereby adjusting the protruding length of the tip of the needle 3; the protruding length of the tip of the needle 3 is adjusted to 0.9 mm;.

[0235] Step 4: Measure the eye to be injected and confirm the injection site with a measuring instrument;

[0236] Step 5: Holding the syringe case, position the clamp hole 112 of the connecting cylinder 1 perpendicular to the surface of the eye tissue at the injection site;

[0237] Step 6: bringing the clamping hole 112 of the connecting cylinder 1 into contact with the eye tissue at the injection site by interaction of the syringe 4 of the ocular injection device and the syringe case, and applying force to the eye tissue at the injection site so that the conjunctival tissue clamped by the clamping hole 112 of the connecting cylinder 1 protrudes into the injection end 11 of the cylinder 1, forming a protrusion 32, and the tip of the needle 3 is pressed into the target eye tissue at the injection site;

[0238] Step 7: Press the syringe pusher 4 with the same hand or the other hand to inject so that the drug reaches the target tissue at the injection site.

[0239] During the injection process, the injection situation was recorded, including the following: whether there was movement of the needle 3 toward the syringe 4, backflow of the drug solution, diffusion on the ocular surface and subconjunctival residue, diffusion, bleeding or stagnation; whether there was deviation of the needle tip from the injection site and whether there were any scratches on the ocular surface during the injection; then the rabbit was sacrificed, the eyeballs were dissected and flat fundus tissue samples were prepared, and the distribution of the ICG solution in the suprachoroidal space was recorded using photographs.

[0240] Test Result: The observation result showed that needle 3 did not move toward syringe 4, there was no reflux or diffusion on the ocular surface, no residue, bleeding, or congestion under the mucous membrane, no deviation from the injection site, and no scratches on the ocular surface near the injection site. The result of the fundus tissue section is shown in Fig. 27. Almost all of the fundus tissues were transfected with ICG, and the stained fundus tissues were dark green. The above experimental result proved that the injection was successful.

[0241] Test Example 5

[0242] The differences from Test Example 4 are as follows: the inner diameter of the clamping hole 112 of the connecting cylinder 1 was 1.0 mm, the length of the blade was 450±50 μm, and the length of the open tip of the needle 3 was 0.7 mm.

[0243] Test Result: The observation result showed that needle 3 did not move toward syringe 4, there was no reflux or diffusion on the ocular surface, no residue, bleeding, or congestion under the mucous membrane, no deviation from the injection site, and no scratches on the ocular surface near the injection site. The result of the fundus tissue section is shown in Fig. 28. Almost all of the fundus tissues were transfected with ICG, and the stained fundus tissues were green. The above experimental result proved that the injection was successful.

[0244] Test Example 6

[0245] The differences from Test Example 4 are as follows: the inner diameter of the clamping hole 112 of the connecting cylinder 1 was 3.0 mm, the length of the blade was 450±50 μm, and the length of the open tip of the needle 3 was 0.7 mm.

[0246] Test result: The observation result showed that needle 3 did not move toward syringe 4, there was no reflux or diffusion on the ocular surface, no residue, bleeding, or congestion under the mucous membrane, no deviation from the injection site, and no scratches on the ocular surface near the injection site. The result of the fundus tissue section is shown in Fig. 29. The area of ​​the fundus tissue transfected with ICG exceeded 4 / 5, and the stained fundus tissue was dark green. The above experimental result proved that the injection was successful.

[0247] Test Example 7

[0248] The differences from Test Example 4 are as follows: the syringe case, syringe and injection device in Case 2 were used, and the blade length was 500±50μm;

[0249] Injection method: Needle 3 with a shaft length of 6.8 mm was selected and installed on syringe 4 according to requirements, and the exposed tip length of needle 3 was 0.8 mm. The operator's finger was placed on the limiting structure 24 and fixed relative to the syringe case, while the syringe case was held in the same hand for the operation.

[0250] Test Result: The observation result showed that needle 3 did not move toward syringe 4, there was no drug reflux, no diffusion on the ocular surface, and no residue, bleeding, or stagnation under the mucous membrane at the injection site. The result of the ocular fundus tissue section is shown in Fig. 30. Almost all of the ocular fundus tissues were transfected with ICG, and the stained fundus tissues were dark green. There was no deviation from the injection site, and there were no scratches on the ocular surface near the injection site. The above experimental result proved that the injection was successful.

[0251] Test Example 8

[0252] The differences from Test Example 4 are as follows: the syringe case, syringe, and injection device in Case 6 were used, and the blade length was 350±50 μm;

[0253] Injection method:

[0254] Step 1: inserting the syringe barrel 4 into the positioning cylinder 2 from the upper end of the positioning cylinder 2 and rotating the syringe barrel 4 to move the flange 41 of the syringe barrel into the installation groove 21, thereby completing the fixation of the syringe 4 and the positioning cylinder 2 relative to each other;

[0255] Step 2: Install the drug suction needle on the distal end of the syringe barrel 4 and complete the drug suction operation;

[0256] Step 3: Select needle 3 with 6.7mm shaft length and place needle 3 in connecting cylinder 1;

[0257] Step 4: remove the drug suction needle and insert the connecting barrel 1 with the needle 3 into the distal end of the syringe barrel;

[0258] Step 5: rotating the connecting cylinder 1 in the forward direction and moving the cylinder 1 with the needle 3 toward the distal end of the syringe barrel, so that the tip of the needle 3 moves to the injection end of the cylinder 1; adjusting the length of the tip of the needle 3 protruding from the cylinder 1 by adjusting the overall length of the connection between the cylinders 1 and 2; eventually, the cylinder 1 abuts against the syringe barrel and cannot move backward, and the length of the exposed tip of the needle 3 is the current length of 0.7mm;

[0259] Step 6: Measure the eye where the drug will be injected and confirm the injection site with a measuring instrument;

[0260] Step 7: Holding the syringe case, position the clamp hole 112 of the connecting cylinder 1 perpendicular to the surface of the eye tissue at the injection site;

[0261] Step 8: bringing the clamping hole 112 of the connecting cylinder 1 into contact with the eye tissue at the injection site by interaction of the syringe 4 of the ocular injection device and the syringe case, and applying force to the eye tissue at the injection site so that the conjunctival tissue clamped by the clamping hole 112 of the cylinder 1 protrudes into the injection end 11 of the cylinder 1, forming a protrusion 32, and the tip of the needle 3 is pressed into the target eye tissue at the injection site;

[0262] Step 9: Press the syringe pusher 4 with the same hand or the other hand to inject so that the drug reaches the target tissue at the injection site.

[0263] Test Result: The observation result showed that needle 3 did not move toward syringe 4, there was no reflux or diffusion on the ocular surface, no residue, bleeding, or congestion under the mucous membrane, no deviation from the injection site, and no scratches on the ocular surface near the injection site. The result of the fundus tissue section is shown in Fig. 31. Almost all of the fundus tissues were transfected with ICG, and the stained fundus tissues were dark green. The above experimental result proved that the injection was successful.

[0264] Test Example 9

[0265] The injection device and injection method described in Embodiment 4 were used.

[0266] Test animal: one rhesus macaque.

[0267] Injection frequency: single injection, OS (left eye); the day of administration to the animal was defined as the first day of the test;

[0268] Introduced reagent: rAAV-anti-VEGF

[0269] Dosage and concentration: dosage: 1.0×10 12 vg / eye (viral genome / eye), concentration: 1.0×10 13 vg / ml.

[0270] Injection volume: 100μL / eye.

[0271] Administration method: After anesthesia of the rhesus macaque, the eye to be injected with the drug was disinfected with povidone-iodine solution; under an operating microscope, the eyelid was opened with an eyelid opener and the surgical site was exposed; the injection device described in Example 4 of the test was used, a 3-gauge needle with a shaft length of 6.7 mm was selected, and the open tip length of the 3-gauge needle was adjusted to 0.7 mm; from the posterior side of the vitreous pars plana, the needle penetrated the sclera above the superior temporal region of the eyeball to complete the injection and enter the suprachoroidal space. After the operation, Ofloxacin ophthalmic ointment was applied as drops to both eyes to prevent corneal wetting and protect against infection.

[0272] During the injection process, the injection situation was recorded, including the following: whether there was movement of the needle 3 toward the syringe 4, outflow of the drug solution, diffusion on the ocular surface and subconjunctival residue, diffusion, bleeding or congestion; whether there was deviation of the needle tip from the injection site and scratches on the ocular surface during injection;

[0273] After 13 weeks of administration, rhesus macaques were sacrificed and important ocular tissues such as aqueous humor, vitreous, iris / ciliary body, retina, choroid, and sclera were collected, and then PCR testing was performed to investigate the distribution of vector genomic DNA concentration in ocular tissues.

[0274] Where:

[0275] Quantitative limit: vector genomic DNA concentration = 2.0 × 10 4 vg / ml;

[0276] Tissue sample detection limit: 2.5 × 10 4 vg / g tissue;

[0277] Detection limit of aqueous humor and vitreous humor samples: 1.25 × 10 3 vg / ml of aqueous humor and vitreous body sample.

[0278] Test Result:

[0279] The injection observation result showed that the needle 3 did not move toward the syringe 4, there was no reflux or diffusion on the ocular surface, there was no residue, bleeding or stagnation under the mucous membrane, there was no deviation from the injection site, and there were no scratches on the ocular surface near the injection site.

[0280] Through the detection of the concentration distribution of the target gene in the ocular tissues (as shown in Table 3), it is known that the target gene is mainly distributed in the sclera and choroid, and the above test is consistent with the characteristics of injection into the suprachoroidal space.

[0281] Table 3 - Distribution of target gene concentration in the main tissues of the eye

[0282] Collection time Eye Iris / ciliary body (vg / g) Retina (vg / g) Choroid (vg / g) Sclera (vg / g) Aqueous humor (vg / ml) Vitreous body (vg / ml) Week 13 OS 6.56E+08 1.93E+07 1.52E+10 8.58E+10 BLD BLQ

[0283] Note: BLQ means "below limit of quantification" and BLD means "below limit of detection".

[0284] Observation of the injection situation and the distribution of the target gene concentration in the ocular tissues showed that the injection into the suprachoroidal space in this trial was successful.

[0285] Although the present invention has been described above in certain preferred embodiments, it is not limited to these embodiments. Any modification, equivalent replacement, or improvement, etc., made in the spirit and principle of the present invention may be considered to fall within the scope of its protection. The arrangement of parts can be adjusted adaptively for specific parts located in specific orientations or positions, as shown in the above schematic diagrams and / or embodiments. Likewise, the order of specific methods and / or steps described herein can be adjusted. Although embodiments have been specifically shown and described, it can be understood that various modifications in form and detail can be made.

[0286] Although the device and method described herein are described and illustrated as being used to deliver a drug to the suprachoroidal space, in other embodiments, the device and method described herein can be used to deliver any suitable therapeutic substance to any part of the eye, such as the cornea, mucosa, retinal region, or vitreous humor. In other embodiments, any of the devices and methods described herein can be used to deliver any suitable therapeutic substance to any desired target tissue of the eye.

Claims

1. A syringe case with a needle containing the following components for attachment to the syringe: positioning cylinder for attachment to the syringe barrel flange and a connecting cylinder having a connecting end and an injection end, wherein the connecting end is used for connecting to a positioning cylinder, and the injection end is used to limit a portion of the tip of the needle protruding from the connecting cylinder, wherein an annular projection is provided on the inner side of the injection end or the injection end has a tapering part for clamping the needle connector and limiting the needle.

2. The case according to claim 1, in which, when the connecting cylinder and the positioning cylinder are connected to each other, the overall length of these cylinders is made variable by means of this connection.

3. A case according to claim 1, in which raised ribs are provided on the periphery of the upper end of the needle connector for clamping on the annular projection and limiting the length of the needle protruding from the injection end by the annular projection.

4. The case according to claim 1, in which, when adjusting the length of the tip of the needle protruding from the connecting cylinder through the injection end, the annular projection clamps the needle connector.

5. A case according to any one of paragraphs 1-4, in which the tip of the injection end has a clamping hole for pressing the tissue of the eye at the injection site, and the clamping hole has an annular end surface with an internal diameter of from 1 mm to 3 mm.

6. A case according to any one of claims 1 to 5, in which the connecting end is connected to the positioning cylinder by means of a threaded connection or a snap connection, and the connecting end is designed to be connected to the positioning cylinder from the end of the positioning cylinder facing the needle, or the connecting end is designed to be inserted into the positioning cylinder and connected to it from the end of the positioning cylinder facing the tail end of the syringe rod.

7. A case according to any one of claims 1 to 6, in which the inner wall of the connecting cylinder has a positioning groove extending in the axial direction for mutual clamping with the outer side of the syringe barrel or the outer side of the needle connector, so that the syringe is configured to move in the axial direction of the connecting cylinder under the direction of the positioning groove.

8. A case according to any one of claims 1 to 7, wherein the positioning cylinder has a mounting groove for mounting a flange of the syringe barrel, so that the flange of the syringe barrel is clamped in the mounting groove by rotation.

9. A case according to any one of claims 1 to 8, in which the portion of the tip of the needle protruding from the connecting barrel is limited by the injection end, so that the syringe secures the needle connector.

10. A case according to any one of paragraphs 1-9, in which on the outer side of the positioning cylinder there is a limiting structure for fixing the fingers of the operator, wherein the limiting structure is a protrusion, a recess or an annular structure.

11. A syringe case containing a needle and the following components for attachment to the syringe: positioning cylinder for attachment to the syringe barrel flange and a connecting cylinder having a connecting end and an injection end, wherein the connecting end is configured to be connected to the positioning cylinder, wherein the injection end is connected to the needle by means of a needle connector and limits the portion of the tip of the needle protruding from the injection end, wherein an annular projection is formed on the inner side of the injection end of the connecting cylinder, or the injection end of the connecting cylinder has a tapering part for clamping the needle connector and limiting the needle.

12. The case according to claim 11, in which, when the injection end and the connector are connected to each other, the total length of the injection end and the connector is made variable by means of said connection.

13. The case of claim 11, wherein the syringe secures the connector when the injection end defines a portion of the tip of the needle protruding from the injection end, and wherein there is a Luer connector between the end of the positioning cylinder facing the connecting cylinder and the needle connector, so that the needle connector is configured to connect with the syringe in the positioning cylinder to form a single structure.

14. A case according to any one of claims 11-13, in which the connecting end of the connecting cylinder is connected to the lower end of a positioning cylinder rigidly connected to the syringe barrel after its connection with the needle connector, so that the connector is connected to the syringe in the positioning cylinder, forming a single structure.

15. An injection unit comprising a syringe case with a needle according to any one of claims 1-10, and a syringe placed in a connecting cylinder and a positioning cylinder, wherein the flange of the syringe barrel is clamped in the mounting groove of the positioning cylinder, and the length of the syringe needle protruding from the connecting cylinder is adjusted by means of a connection between the connecting cylinder and the positioning cylinder or a connection between the connecting cylinder and the needle connector.

16. The injection unit of claim 15, wherein the syringe is a pre-filled syringe.

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