A pediatric lacrimal probe and method of manufacturing the same

Abstract

The application discloses a pediatric lacrimal passage probe and a manufacturing method thereof, and belongs to the technical field of ophthalmic medical instruments. The probe is integrally formed by selective laser melting 3D printing of a medical titanium alloy, and comprises a round blunt smooth probe head, a gradually variable diameter rod body, an axial micro drug storage groove and an integrated handle. The surface of the probe is covered with a silver ion, calcium ion and strontium ion co-doped titanium dioxide nanotube coating. The application eliminates the fracture weak point of a traditional welded probe through the welding seam-free integrated structure, takes into account the front end flexibility and the rear end bending strength through the gradually variable diameter rod body, realizes synchronous drug delivery during the probe passing through through the axial micro drug storage groove on the outer surface of the entity, and realizes the synergistic effect of high hydrophilicity, low friction, bacteriostasis and calcium and strontium ion assisted tissue repair through the ternary ion co-doped titanium dioxide nanotube coating. The application is suitable for the treatment of pediatric congenital lacrimal passage obstruction, dacryocystitis and other diseases, and can reduce the risk of broken needle, mucosal injury, infection and postoperative recurrence.

Description

Technical Field

[0001] This invention relates to the field of ophthalmic medical device technology, specifically to a pediatric lacrimal duct probe for the treatment of congenital lacrimal duct obstruction in children, neonatal dacryocystitis, and lacrimal duct stenosis in infants and young children, and its manufacturing method. In particular, it relates to a pediatric lacrimal duct probe made of selective laser melting 3D printing integrally formed titanium alloy, having a gradient diameter structure, a drug storage groove on the solid outer surface, and a silver / calcium / strontium ternary ion co-doped titanium dioxide nanotube coating, and its manufacturing method. Background Technology

[0002] Congenital lacrimal duct obstruction and dacryocystitis are common pediatric ophthalmological diseases. The preferred clinical treatment is usually lacrimal duct probing. Traditional lacrimal duct probes often have the following problems:

[0003] Firstly, some traditional lacrimal duct probes use welded, threaded, or glued structures for the needle body and handle. The welded area is at risk of metal fatigue and breakage after long-term bending, high-temperature and high-pressure sterilization, and repeated use. If the broken end remains in the lacrimal duct, it can form an intraocular foreign body, requiring a second surgery for removal.

[0004] Secondly, traditional stainless steel probes have poor hydrophilicity, resulting in greater frictional resistance during probing, which can easily damage the delicate lacrimal duct mucosa of children, potentially leading to edema, adhesions, and recurrence of the condition after surgery.

[0005] Third, some existing improvement schemes use hollow injection channels or side-hole injection structures. Although they can achieve simultaneous flushing or drug delivery, the internal cavity will weaken the solid cross-section of the rod and may cause problems such as tissue embedding, machining welds, and cleaning dead corners.

[0006] Fourth, existing antibacterial coating studies have disclosed solutions such as silver-loaded titanium dioxide nanotubes, or silver / calcium-loaded or silver / strontium-loaded solutions. However, these solutions are mostly geared towards orthopedic implants or general titanium surface modification, and have not proposed a systematic integration of gradient diameter structure, axial drug storage groove, and silver / calcium / strontium ternary ion co-doped titanium dioxide nanotube coatings for pediatric lacrimal duct probes.

[0007] Therefore, there is an urgent need for a pediatric lacrimal duct probe that is structurally safe, minimally invasive, allows for simultaneous drug delivery, and combines antibacterial and tissue repair functions. Summary of the Invention

[0008] The technical problems to be solved by this invention include: traditional welding probes have the risk of weld fatigue and needle breakage; the probe rod has uniform stiffness, making it difficult to simultaneously consider the flexibility of the anterior segment and the control strength of the posterior segment of the pediatric lacrimal duct; although existing hollow injection probes can be connected to syringes for direct drug administration after probing, their internal lumen weakens the solid cross-section of the rod and may cause problems such as tissue embedding, cleaning dead corners, and weld processing, and drug administration depends on external syringe injection rather than continuous migration during the probing process; the surface of stainless steel has poor hydrophilicity, resulting in high probing friction and easy damage to the lacrimal duct mucosa; existing antibacterial or repair solutions are scattered and have not formed an integrated system of "mechanical structure - drug delivery channel - biological functional coating" adapted to the physiological characteristics of the pediatric lacrimal duct.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A pediatric lacrimal duct probe for pediatric lacrimal duct probing includes a solid probe body integrally manufactured from medical-grade titanium alloy powder through selective laser melting additive manufacturing. The solid probe body comprises a rounded, smooth probe head, a gradually decreasing diameter rod with axially oriented micro-drug reservoirs, and an integrated handle. The solid probe body does not contain a drug injection lumen, nor does it have any separate welded, threaded, or adhesive joints.

[0011] The gradually changing diameter rod is a solid rod with a continuously changing outer diameter along the axial direction. The minimum outer diameter D1 near the probe end is 0.30 mm to 0.80 mm, and the maximum outer diameter D2 near the handle end is 0.80 mm to 1.50 mm, with a D2 / D1 ratio of 1.5 to 3.0. The side of the gradually changing diameter rod near the probe end is formed as a flexible section conforming to the physiological curvature of the pediatric lacrimal duct, while the side near the handle is formed as a rigid section to improve bending stiffness.

[0012] The axial micro-drug reservoir is a non-through shallow groove formed on the outer surface of the gradually changing diameter probe. The groove depth h is 0.02 mm to 0.15 mm, and the distance from the bottom of the groove to the axis of the probe is not less than 30% of the outer diameter of the probe at that location. The bottom of the groove retains a solid cross-section. Before surgery, the groove absorbs and carries the anti-inflammatory drug solution, and during surgery, the drug solution continuously migrates to the probe surface through capillary action.

[0013] The probe head, the gradually tapering rod, and the axial micro-drug reservoir are coated with titanium dioxide nanotubes. The titanium dioxide nanotube coating is an ordered array of nanotubes formed by anodizing a titanium alloy substrate. The nanotubes have a diameter of 30 nm to 150 nm, and their walls and / or bottoms are co-doped with silver, calcium, and strontium ions. Silver ions are used for sustained-release antibacterial action, while calcium and strontium ions are used to regulate the behavior of lacrimal duct mucosal cells and assist in tissue repair. The nanotube array topology enhances surface hydrophilicity and reduces the probe's friction coefficient.

[0014] The present invention also provides a method for manufacturing the above-mentioned pediatric lacrimal duct probe, comprising: establishing a three-dimensional model of the probe; using selective laser melting to integrally print the probe head, the gradually changing diameter rod, the drug storage groove and the handle; polishing and heat-treating the printed body; constructing a titanium dioxide nanotube array by anodizing on the surface of a titanium alloy; and using post-treatment to co-dope silver, calcium and strontium ions into the nanotube array to form a co-doped coating.

[0015] The present invention has the following beneficial effects:

[0016] 1. Seamless one-piece molding reduces the risk of needle breakage: Selective laser melting 3D printing is used to form the probe head, rod body, drug reservoir and handle in one piece, eliminating the weak points of traditional welding, and resisting repeated high temperature and high pressure sterilization, reducing the risk of intraocular foreign bodies formed by the broken end leaving the lacrimal duct.

[0017] 2. Gradual diameter adjustment to fit the pediatric lacrimal duct: The front end is soft and the back end is rigid, which is conducive to passing through the narrow and tortuous pediatric lacrimal duct, while ensuring the surgeon's stable force application and reducing the risk of false passage and mucosal tearing.

[0018] 3. Synchronous drug loading, reducing secondary damage: The non-penetrating drug storage groove on the outer surface of the probe can absorb anti-inflammatory drugs before surgery. During the probing process, the drug can be continuously transferred to the probe surface and moisten the lacrimal duct by capillary action without the need to connect a syringe. This avoids the shortcomings of traditional hollow injection needles that rely on the internal lumen to weaken the rod and require external injection, thus relieving edema and adhesion.

[0019] 4. High hydrophilicity and low friction reduce mucosal damage: The titanium dioxide nanotube array significantly improves the surface hydrophilicity, and when combined with a rounded and smooth probe, it can reduce the probing resistance and reduce mechanical damage to the lacrimal duct mucosa of children.

[0020] 5. Synergistic effect of antibacterial and tissue repair: Silver ions exert a slow-release antibacterial effect, while calcium and strontium ions help regulate cell behavior and tissue repair. The three are co-doped in the same nanotube coating, which takes into account both anti-infection and tissue recovery, and reduces postoperative recurrence.

[0021] 6. Structure-Function-Bio Integration: The gradient structure reduces scratches and protects the physical stability of the coating; the drug storage tank uses capillary effect to continuously replenish the drug solution to the coating surface, making up for the gap period of ion release; the hydrophilic structure of nanotubes guides the uniform spread of calcium and strontium ions and drug solution, forming a mutually reinforcing overall solution.

[0022] 7. Stress relief section further resists fracture: The stress relief section between the probe head and the rod body transitions with a lower outer diameter change rate, so that the bending moment is released preferentially in this section, avoiding stress concentration at the root of the probe head or the starting point of the diameter change, and improving the fatigue life of the one-piece molded probe under repeated bending. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. The drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort:

[0024] Figure 1 This is a schematic diagram of the overall structure of the pediatric lacrimal duct probe according to an embodiment of the present invention;

[0025] Figure 2 for Figure 1 A partially enlarged schematic diagram shows the relationship between the axial micro-drug storage groove and the gradually changing diameter rod.

[0026] Figure 3 This is a magnified schematic diagram of a partial cross-section of the titanium dioxide nanotube coating according to an embodiment of the present invention;

[0027] Figure 4 This is a flowchart of the method for preparing a pediatric lacrimal duct probe according to an embodiment of the present invention.

[0028] Explanation of reference numerals in the attached drawings: 1-Probe head; 11-Flexible section; 2-Rod body; 3-Drug storage groove; 4-Handle; 41-Rigid section; 5-Titanium dioxide nanotube coating; 51-Silver ion doped region; 52-Calcium ion doped region; 53-Strontium ion doped region; 6-Stress relief section. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, a clear and complete description will be provided below in conjunction with the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0030] like Figure 1-3 As shown, the pediatric lacrimal duct probe of the present invention includes a blunt, smooth probe head 1, a gradually decreasing diameter rod body 2, an axial micro-drug reservoir 3, and an integrated handle 4. The above structure is integrally formed by selective laser melting 3D printing of medical-grade titanium alloy, and there is no separate welding, threaded splicing, or adhesive connection between the head and the rod body. The solid probe body also does not have a drug injection lumen.

[0031] The probe head 1 is located at the tip of the probe and is used to enter the lacrimal punctum, lacrimal canaliculus, lacrimal sac, and nasolacrimal duct. Its tip is a rounded and smooth structure, without sharp edges, burrs, or protrusions. The transition between the head end face and the side face of the rounded and smooth probe head 1 preferably adopts a continuous arc transition, with the radius of the arc set to 0.5 to 1.5 times the minimum outer diameter D1, to avoid local stress concentration and reduce the risk of puncture injury when inserted into the lacrimal punctum.

[0032] The gradually increasing diameter rod 2 extends from the probe head 1 towards the handle 4, with its outer diameter gradually increasing from the end closer to the probe head 1 to the end closer to the handle 4. The side closer to the probe head 1 forms a flexible section 11, and the side closer to the handle 4 forms a rigid section 41. The cross-section of the flexible section 11 remains completely circular, without becoming elliptical or angular due to the diameter change, thus preventing the edges from scraping the mucosa during probe insertion. The cross-section of the rigid section 41 also remains circular, and its increased outer diameter increases the moment of inertia of the section, significantly enhancing its bending stiffness.

[0033] Preferably, the gradually tapering rod 2, from the probe head 1 to the handle 4, comprises a flexible section 11, a diameter transition zone, and a rigid section 41. The diameter transition zone is located within 30% to 60% of the rod length from the probe head 1; the flexible section 11 and the rigid section 41 are located on both sides of the diameter transition zone, and preferably each accounts for 30% to 70% of the rod length, with the sum of their lengths and the diameter transition zone being the total length of the rod. This structure allows the probe tip to conform to the curvature of the child's lacrimal duct while maintaining sufficient controllability at the rear end.

[0034] A smooth, rounded probe head 1 and a gradually tapering rod 2 with a stress-relieving section 6 provided between their minimum outer diameter ends. The stress-relieving section 6 has a length of 0.5 mm to 3.0 mm, and its outer diameter change rate is lower than the radial change rate of the rest of the gradually tapering rod 2. The principle is as follows: the lacrimal duct of children is narrow, has many bends, and the mucous membrane is delicate. If the rod is of a constant diameter and relatively rigid throughout, the front end will not easily conform to the bends of the lacrimal duct; if it is too soft throughout, the force applied by the handle at the rear end cannot be effectively transmitted. This invention, through continuous diameter change and stress-relieving section 6, allows the bending moment to be preferentially released in the stress-relieving section, avoiding stress concentration at the root of the probe head.

[0035] refer to Figure 1 and Figure 2 The axial micro-drug reservoir 3 is a non-through shallow groove structure formed on the outer surface of the rod 2. While retaining the solid cross-section of the rod 2, it relies on capillary action to adsorb the drug solution. The groove depth h of the axial micro-drug reservoir 3 is 0.02 mm to 0.15 mm, and at any cross-section where the groove is formed, the distance from the bottom of the groove to the axis of the rod is not less than 30% of the outer diameter of the rod at that position, that is, the groove depth is not greater than 20% of the outer diameter of the rod at that position. The bottom of the groove retains a solid cross-section, so the non-through shallow groove does not weaken the overall bending strength of the probe, nor does it form an internal cavity for tissue embedding.

[0036] In a further embodiment, the axial micro-drug storage groove 3 has a semi-circular, shallow U-shaped, or trapezoidal shallow groove in cross-section. The bottom of the groove is provided with a micro-nano corrugated structure along the extension direction of the groove. The peak height of the micro-nano corrugations is in the range of 0.5 μm to 5 μm. Its function is to increase the specific surface area of ​​the groove bottom and generate a Laplace pressure difference, thereby enhancing the capillary adsorption capacity. The groove 3 can be provided with one, two, or more grooves. When there are multiple grooves, they are evenly distributed along the circumference of the rod or symmetrically distributed on both sides of the rod, so that they can contact the lacrimal duct wall to administer the drug when the probe rotates around its own axis. The width of the outer edge opening of the groove 3 is not greater than the width of the groove bottom, preferably slightly smaller than the width of the groove bottom, forming a slightly converging opening to prevent the drug solution from being quickly scraped off when the probe is withdrawn.

[0037] refer to Figure 3 The titanium dioxide nanotube coating 5 is an ordered nanotube array formed by anodic oxidation, with silver, calcium, and strontium ions co-doped in the tube walls or bottom. Traditional resin-based antibacterial layers or single silver-loaded layers cannot simultaneously achieve low friction, slow-release antibacterial action, and tissue repair regulation. This invention constructs a nanotube array in situ on the surface of a titanium alloy through anodic oxidation, allowing silver, calcium, and strontium ions to enter the nanotube structure, forming an Ag / Ca / Sr ternary co-doped coating (51, 52, 53).

[0038] In a further implementation, the nanotube array of the titanium dioxide nanotube coating 5 is segmented along the axial direction of the rod: the average diameter of the nanotubes on the surface of the flexible segment 11 is smaller, for example, 30 nm to 80 nm, to enhance capillary spreading; the average diameter of the nanotubes on the surface of the rigid segment 41 is larger, for example, 80 nm to 150 nm, to increase the ion loading, and the average diameter of the flexible segment is smaller than that of the rigid segment. The entire structure maintains ternary co-doping with silver, calcium, and strontium.

[0039] Silver nitrate is preferred as the silver ion source, calcium nitrate as the calcium ion source, and strontium nitrate as the strontium ion source. Post-treatment can involve ultraviolet irradiation or low-temperature heat treatment to remove some Ag. + The nanoparticles are reduced to silver nanoparticles and fixed at the bottom of the tube, while calcium and strontium ions are deposited on the tube wall as hydroxides or oxyacid salts, forming an Ag / Ca / Sr ternary co-doped structure. Characterization of this coating showed a significant reduction in contact angle, confirming improved hydrophilicity.

[0040] In terms of manufacturing details, the probe head 1, the tapered rod 2, the drug reservoir 3, and the handle 4 are all printed from the same titanium alloy substrate, with no welds or splices. During selective laser melting printing, the probe length direction is arranged at an angle of 30° to 90° with the printing layer thickness direction, so that the axial force direction of the tapered rod 2 forms a reasonable angle with the interface between the cladding layers, reducing the adverse effect of the weak surface between the layers on fatigue performance. The printing support is only placed in the non-working area of ​​the handle 4. The suspended section of the probe head 1 and the rod 2 is directly formed through process optimization, and the working section is polished after the support is removed.

[0041] This invention clearly distinguishes itself from existing hollow lacrimal duct patency testing needles. Hollow needles rely on internal tubing or side holes to expel medication, but this internal tubing weakens the solid cross-section and can potentially cause tissue impaction or cleaning dead zones during testing. This invention uses a non-through shallow groove on the outer surface of a solid rod. The distance from the bottom of the groove to the rod's axis is no less than 30% of the rod's outer diameter at that location, thus maintaining a continuous solid cross-section. The medication is not forced out from the internal tubing, but rather migrates to the probe surface via capillary force from the drug storage groove and the hydrophilicity of the titanium dioxide nanotube coating, thereby achieving simultaneous drug delivery during testing while maintaining the rod's strength.

[0042] Example 1

[0043] A pediatric lacrimal duct probe has a minimum outer diameter (D1) of 0.50 mm for the probe head and a maximum outer diameter (D2) of 1.00 mm near the handle end, with a D2 / D1 ratio of 2.0. The total length of the gradually decreasing diameter rod is 25 mm, with a flexible section of 12 mm and a rigid section of 13 mm. An axial micro-drug reservoir has a depth of 0.05 mm and a width of 0.30 mm, with micro-nano corrugations of approximately 1 μm in height at the bottom. The distance from the bottom of the reservoir to the rod's axis is not less than 30% of the rod's outer diameter at that location, thus the rod's solid cross-section is not weakened by penetration. A 1.5 mm long stress-relieving section is provided between the rounded, smooth probe head and the minimum outer diameter end of the gradually decreasing diameter rod. The probe's working section surface is anodized to form a titanium dioxide nanotube array; the flexible section nanotubes have a diameter of approximately 50 nm, and the rigid section nanotubes have a diameter of approximately 100 nm. The nanotube array is co-doped with silver, calcium, and strontium ions.

[0044] Example 2

[0045] Unlike Example 1, the minimum outer diameter D1 of the probe is 0.60 mm, and the maximum outer diameter D2 of the rod is 1.20 mm. The flexible section accounts for approximately 55% of the rod length, and the rigid section accounts for approximately 45%. The depth of the drug storage groove is 0.06 mm, and the width is 0.35 mm. The diameter of the nanotubes in the flexible section is 60 nm to 80 nm, and the diameter of the nanotubes in the rigid section is 90 nm to 120 nm.

[0046] Example 3

[0047] Unlike Example 1, the minimum outer diameter D1 of the probe is 0.70 mm, and the maximum outer diameter D2 of the rod is 1.40 mm. This specification is suitable for older children or children with relatively large lacrimal ducts, and the proportion of the rigid section is correspondingly increased. The depth of the drug reservoir is 0.08 mm, and the width is 0.40 mm.

[0048] Manufacturing method examples

[0049] like Figure 4As shown, the manufacturing method of the above-mentioned pediatric lacrimal duct probe includes the following steps:

[0050] Step 1: Establish a three-dimensional model of the probe, which includes a rounded and smooth probe head, a gradually changing diameter rod with an axial micro-drug storage groove, a stress relief section, and an integrated handle; the model includes a pre-set stress relief section between the probe head and the rod, and micro-nano ripples at the bottom of the groove.

[0051] Step 2: Select medical-grade TC4 titanium alloy powder and use selective laser melting process to print the aforementioned structure in one piece; select a printing layer thickness of 20 μm to 40 μm, adapt the laser power and scanning speed to TC4 medical-grade titanium alloy, and arrange the probe length direction reasonably relative to the printing layer thickness direction.

[0052] Step 3: Perform mechanical polishing or electrolytic polishing on the probe, focusing on polishing the probe head and flexible section, and then perform vacuum annealing and / or hot isostatic pressing to eliminate residual stress and improve density.

[0053] Step 4: The probe is anodized in a fluorinated ethylene glycol-based electrolyte to form a titanium dioxide nanotube array; the diameters of the flexible and rigid nanotube segments can be made different by segmented parameter control.

[0054] Step 5: Place the probe in a treatment solution containing silver, calcium, and strontium ions to allow the three ions to enter the nanotube structure. Then fix it by low-temperature heat treatment or ultraviolet treatment to form a ternary co-doped coating.

[0055] Step 6: Clean and dry to obtain the pediatric lacrimal duct probe.

[0056] Before the procedure, anti-inflammatory medication is loaded into the axial micro-drug reservoir. After dilating the lacrimal punctum, the surgeon gently inserts the probe along the lacrimal canaliculus. When the probe reaches the site of nasolacrimal duct obstruction, the blunt probe tip is used to gently break through the membranous blockage. During the probing process, the medication in the reservoir and the surface nanotube coating work together on the lacrimal duct mucosa to achieve low-damage probing, simultaneous drug delivery, antibacterial action, and assisted repair.

[0057] The following experimental examples provide a set of real test data to illustrate the technical effects of the present invention.

[0058] 1. Sample setup

[0059]

[0060] 2. Test Results

[0061]

[0062] Note: “—” in the table indicates that the corresponding comparative example did not have a drug storage groove structure, therefore there is no data on the drug liquid retention and capillary migration time in the corresponding drug storage tank.

[0063] 3. Results Explanation

[0064] As can be seen from the above real test data, the embodiments of the present invention significantly reduce the coefficient of friction and improve fatigue life compared with traditional stainless steel welding probes; significantly improve hydrophilicity and antibacterial properties compared with ordinary resin antibacterial coatings; and improve cell compatibility through calcium and strontium ion regulation while maintaining a high antibacterial rate compared with single silver-loaded nanotube coatings. The non-through-hole drug storage groove achieves drug retention and capillary migration while maintaining a solid cross-section, allowing probing and drug delivery to be carried out simultaneously, and eliminating the need for internal lumen and external syringe for injection as with traditional hollow injection needles.

[0065] The above description is merely a preferred embodiment of the present invention and does not limit the scope of protection of the present invention. Any equivalent substitutions in structure, materials, or parameters made based on the technical solution of the present invention should fall within the scope defined by the claims of the present invention. It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the scope of protection of the appended claims.

Claims

1. A pediatric lacrimal duct probe for pediatric lacrimal duct probing, characterized in that, The solid probe body is made of medical titanium alloy powder through selective laser melting and integrated additive manufacturing. The solid probe body includes a rounded and smooth probe head, a gradually changing diameter rod with an axial micro drug storage groove, and an integrated handle. The solid probe body does not have a drug injection cavity, nor does it have any separate welding, threaded splicing, or adhesive interface. The gradually changing diameter rod is a solid rod with a continuously changing outer diameter along the axial direction. Its minimum outer diameter D1 near the probe head is 0.30 mm to 0.80 mm, and its maximum outer diameter D2 near the handle is 0.80 mm to 1.50 mm. The ratio of D2 to D1, D2 / D1, is 1.5 to 3.

0. The gradually tapering rod is formed into a flexible section on the side near the probe head that conforms to the physiological curvature of the child's lacrimal duct, and a rigid section on the side near the handle that improves bending stiffness. The axial micro-drug storage groove is a non-through shallow groove opened on the outer surface of the gradually changing diameter rod. The groove depth h is 0.02 mm to 0.15 mm. At any cross-section where the groove is opened, the distance from the bottom of the groove to the axis of the rod is not less than 30% of the outer diameter of the rod at that position, that is, the groove depth is not greater than 20% of the outer diameter of the rod at that position. The bottom of the groove retains a solid cross-section. The groove described before the operation absorbs and carries the anti-inflammatory drug solution, and during the operation, the drug solution continuously migrates to the probe surface by capillary action. The probe head, the gradually changing diameter rod, and the axial micro-drug storage groove are coated with titanium dioxide nanotubes. The titanium dioxide nanotube coating is an ordered array of nanotubes formed by anodizing on the surface of a titanium alloy substrate. The nanotube diameter is 30 nm to 150 nm, and the tube wall and / or tube bottom are co-doped with silver ions, calcium ions, and strontium ions. Among them, silver ions are used for sustained-release antibacterial activity, calcium ions and strontium ions are used to regulate the behavior of lacrimal duct mucosal cells and assist in tissue repair, and nanotube array topology is used to improve surface hydrophilicity and reduce the friction coefficient of probing.

2. The pediatric lacrimal duct probe according to claim 1, characterized in that, The gradually changing diameter rod body, from the probe head to the handle, includes a flexible section, a diameter transition zone, and a rigid section in sequence; The variable diameter transition zone is located within 30% to 60% of the rod length from the probe head; The flexible section and the rigid section are located on both sides of the variable diameter transition zone, and the flexible section accounts for 30% to 70% of the length of the rod, and the rigid section accounts for 30% to 70% of the length of the rod. The sum of the lengths of the flexible section, the variable diameter transition zone and the rigid section is the total length of the rod. Furthermore, both the cross-sections of the flexible and rigid sections remain perfectly circular, without becoming elliptical or angular due to diameter changes.

3. The pediatric lacrimal duct probe according to claim 1, characterized in that, The cross-section of the axial micro-drug storage groove is a semi-circular, shallow U-shaped, or trapezoidal shallow groove, and the bottom of the groove is provided with a micro-nano corrugated structure along the extension direction of the groove, wherein the peak height of the micro-nano corrugations is 0.5 μm to 5 μm. The width of the opening at the outer edge of the groove is no greater than the width of the bottom of the groove, forming a slightly converging opening to prevent the medicine from being scraped off quickly when the probe is pulled out.

4. The pediatric lacrimal duct probe according to claim 1, characterized in that, A stress-relief section with a smooth transition is provided between the blunt, smooth probe head and the minimum outer diameter end of the gradually changing diameter rod. The length of the stress-relief section is 0.5 mm to 3.0 mm, and its outer diameter change rate is lower than the radial change rate of the rest of the gradually changing diameter rod. The smooth, blunt probe head end face and side face transition adopt a continuous arc transition, with the arc radius being 0.5 to 1.5 times the minimum outer diameter D1.

5. The pediatric lacrimal duct probe according to claim 1, characterized in that, The nanotube array of the titanium dioxide nanotube coating is segmented along the axial direction of the rod: The average diameter of the nanotubes on the flexible segment surface is 30 nm to 80 nm, which is used to enhance capillary spreading. The average diameter of the nanotubes on the rigid section is 80 nm to 150 nm, which is used to increase the ion loading, while the average diameter of the flexible section is smaller than that of the rigid section. Silver ions, calcium ions, and strontium ions are distributed in the nanotube wall, bottom, or opening region, forming an Ag / Ca / Sr ternary co-doped structure.

6. The pediatric lacrimal duct probe according to claim 1, characterized in that, The surface of the axial micro-drug storage groove is covered with the titanium dioxide nanotube coating, and the groove wall and the nanotube coating are continuously connected in the radial direction. Under the action of capillary force, the drug liquid in the groove first fills the micro-nano ripples at the bottom of the groove, and then spreads to the circumference of the rod through the hydrophilic nanotube array to form a continuous liquid bridge of "drug storage groove - nanotube coating - lacrimal duct mucosa", so as to realize continuous drug delivery during the exploration process.

7. The pediatric lacrimal duct probe according to claim 1, characterized in that, The minimum outer diameter D1 of the probe head is 0.40 mm to 0.60 mm, and it is configured for lacrimal duct probing in infants and young children. The axial micro drug storage groove is provided with one, two or more grooves. When there are multiple grooves, they are evenly distributed or symmetrically distributed on both sides of the rod body along the circumference. The length of the groove covers the flexible section and part of the rigid section, so that the probe can contact the lacrimal duct wall to administer the drug when it rotates around its own axis.

8. The pediatric lacrimal duct probe according to claim 1, characterized in that, Of the silver ions, calcium ions, and strontium ions, some silver ions are reduced to silver nanoparticles by ultraviolet light irradiation or low-temperature heat treatment and fixed at the bottom of the nanotube. Calcium ions and strontium ions are deposited on the nanotube wall in the form of hydroxides or oxyacid salts, forming an Ag / Ca / Sr ternary co-doped structure.

9. A method for manufacturing a pediatric lacrimal duct probe as described in any one of claims 1 to 8, characterized in that, Includes the following steps: A three-dimensional model of the probe is established, comprising a blunt, smooth probe head, a gradually decreasing diameter rod with an axial micro-drug storage groove, a stress relief section, and an integrated handle; wherein the minimum outer diameter of the probe head is 0.30 mm to 0.80 mm, the maximum outer diameter of the rod is 0.80 mm to 1.50 mm, and the distance from the bottom of the drug storage groove to the axis of the rod is not less than 30% of the outer diameter of the rod at that location; Medical titanium alloy powder is selected, and selective laser melting process is used to print the probe head, the gradually changing diameter rod, the drug storage groove and the handle in one piece; the printing layer thickness is 20 μm to 40 μm, the probe length direction is at 30° to 90° with the printing layer thickness direction, and the support structure is only arranged in the non-working area of ​​the handle. The printed body is mechanically or electrolytically polished, and then vacuum annealed and / or hot isostatically pressed to eliminate residual stress and improve density. In a fluorinated ethylene glycol-based electrolyte, the surfaces of the probe head, the gradually changing diameter rod, and the drug storage groove are anodized to construct a titanium dioxide nanotube array; the anodizing voltage of the flexible section is 20 V to 30 V, and the anodizing voltage of the rigid section is 30 V to 60 V, forming a nanotube array with a diameter of 30 nm to 150 nm. The anodized probe was placed in a treatment solution containing silver ions, calcium ions and strontium ions, so that the three ions entered the nanotube structure. Then, it was fixed by low-temperature heat treatment or ultraviolet treatment to form an Ag / Ca / Sr ternary co-doped coating. After cleaning and drying, a pediatric lacrimal duct probe is obtained.

10. The manufacturing method according to claim 9, characterized in that, In the treatment solution containing silver ions, calcium ions, and strontium ions, the concentration of AgNO3 is 0.005 mol / L to 0.8 mol / L, the concentration of Ca(NO3)2 is 0.01 mol / L to 0.30 mol / L, and the concentration of Sr(NO3)2 is 0.01 mol / L to 0.30 mol / L. Low-temperature heat treatment or ultraviolet treatment removes some Ag + The nanoparticles are reduced to silver nanoparticles and fixed at the bottom of the nanotubes, while calcium and strontium ions are deposited on the nanotube walls in the form of hydroxides or oxyacids.

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