An OCT needle probe

Abstract

This invention discloses an OCT needle probe, belonging to the field of endoscopic probe technology. It includes a needle tip, a sheath, an optical path assembly, and a fixing adhesive. The needle tip has a hollow structure with an opening at its tip. The sheath is installed inside the needle tip, and the optical path assembly is fixedly installed inside the sheath. The fixing adhesive encapsulates the sheath within the needle tip. The optical path assembly includes a single-mode fiber, a coreless fiber, and a spherical lens. The two ends of the coreless fiber are connected to the single-mode fiber and the spherical lens, respectively. The spherical lens is located at the opening. Laser light is emitted from the single-mode fiber, amplified by the coreless fiber, deflected by the spherical lens, and focused by the curved end face of the spherical lens. The emitted beam exits from the opening. This OCT needle probe, through the beam amplification of the coreless fiber, the total internal reflection of the spherical lens, and the opening of the needle tip, can clearly image biological tissues such as the proximal surfaces of teeth, effectively achieving early detection of proximal caries.

Description

Technical Field

[0001] This invention relates to the field of endoscope probe technology, and in particular to the design of an OCT needle probe. Background Technology

[0002] Optical coherence tomography (OCT) is an optical imaging technique that has become an important method in the field of biomedical imaging due to its non-invasiveness and high resolution. In the dental field, an endoscopic probe is incorporated into an OCT system to image tooth tissue.

[0003] Interproximal caries is a type of dental caries that occurs in the contact area between two teeth or below the contact surface. It is primarily caused by food impaction. As interproximal caries progresses, it gradually forms a cavity. Due to its hidden location, traditional diagnostic methods for interproximal caries suffer from limitations such as difficulty for operators to examine, resulting in low accuracy, and limited probe penetration depth, making it difficult to obtain valuable information.

[0004] In recent years, various research groups have proposed various oral OCT probe designs. In 2018, Walther et al. added a prospective oral OCT probe to a commercial oral endoscope to obtain real-time OCT images of various tissues in the oral cavity. In 2020, Won et al. designed a vision-tunable OCT probe based on a MEMS scanning mirror for imaging plaque and calculus on the inner surfaces of incisors and molars. In 2022, Le et al. combined OCT with light-induced autofluorescence technology to create a lateral oral probe with multi-model imaging capabilities. Although existing mechanical scanning-based probes are highly accurate, they remain bulky and lack flexibility, making it impossible to image adjacent surfaces between two teeth and determine the presence of early proximal caries. Summary of the Invention

[0005] The present invention aims to provide an OCT needle probe. Due to the special characteristics of proximal caries, it is necessary to develop an OCT probe that is small in structure, easy to use, non-invasive, and capable of examining deep information of oral tissues.

[0006] To achieve the above objectives, the technical solution of the present invention is: an OCT needle probe, a needle tip having a hollow structure and an opening at the tip of the needle tip, the opening being a slanted cut; and an optical path assembly installed inside the needle tip, the end of the optical path assembly being located at the opening.

[0007] In a preferred embodiment of the present invention, the needle further includes a first oblique surface and a second oblique surface, the first oblique surface being located at the opening, the second oblique surface being located on the opposite side of the opening, the front ends of the first oblique surface and the second oblique surface being close to each other and intersecting to form a tip, and the inclination angle of the first oblique surface being greater than the inclination angle of the second oblique surface.

[0008] In a preferred embodiment of the present invention, the first oblique cut surface is a single line or multiple broken lines.

[0009] In a preferred embodiment of the present invention, a fixing adhesive is further included, which encapsulates the optical path component within the needle tip, and the first beveled surface is formed by the fixing adhesive encapsulating the opening.

[0010] In a preferred embodiment of the present invention, the optical path assembly includes a single-mode fiber, a coreless fiber, and a spherical lens, wherein the two ends of the coreless fiber are respectively connected to the single-mode fiber and the spherical lens, and the spherical lens is located at the opening.

[0011] In a preferred embodiment of the present invention, the spherical lens is surface polished at a 48° angle.

[0012] In a preferred embodiment of the present invention, the radius of curvature of the spherical lens is 0.16 mm, and the length of the coreless optical fiber is 0.53 mm.

[0013] In a preferred embodiment of the present invention, a sheath is further included, the sheath being fixed inside the needle, and the optical path assembly being installed inside the sheath.

[0014] In a preferred embodiment of the present invention, the sheath is a glass tube.

[0015] In a preferred embodiment of the present invention, the inner diameter of the sheath is 0.3 mm and the outer diameter is 0.42 mm.

[0016] The OCT needle probe of this invention can clearly image biological tissues such as the proximal surfaces of teeth through beam expansion of coreless optical fiber, total reflection of spherical lens and needle opening, effectively realizing the early detection of proximal caries; moreover, the OCT needle probe is simple to manufacture, small in size and easy to hold, which greatly facilitates the clinical operation of doctors.

[0017] To make the above-mentioned features and advantages of the invention more apparent and understandable, specific embodiments are described below, and detailed descriptions are provided in conjunction with the accompanying drawings. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a needle-type OCT probe according to the present invention.

[0019] Figure 2This is a schematic diagram of the optical path of the optical path component of the present invention.

[0020] Figure 3 The graph shows the relationship between the length of the coreless optical fiber and the diameter of the focused spot when the radius of curvature r of the spherical lens is 0.16 mm.

[0021] Figure 4 The graph shows the relationship between the length of the coreless optical fiber and the diameter of the focused spot when the radius of curvature r of the spherical lens is 0.16 mm.

[0022] Figure 5 This is an intensity map of a healthy tooth sample imaged using an OCT needle probe.

[0023] Figure 6 This is an intensity map of a tooth sample with proximal caries imaged using an OCT needle probe.

[0024] 1-OCT needle probe; 11-needle tip; 111-opening; 112-first beveled surface; 113-second beveled surface; 12-sheath; 13-optical path assembly; 131-single-mode fiber; 132-coreless fiber; 133-spherical lens; 14-fixing adhesive.

[0025] In the accompanying drawings, similar reference numerals refer to the same elements. Detailed Implementation

[0026] To make the objectives and technical solutions of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0027] like Figure 1As shown, an OCT needle probe 1 is connected to an OCT imaging system for imaging teeth and diagnosing early interproximal caries. The OCT needle probe 1 includes a needle 11, a sheath 12, an optical path assembly 13, and a fixing adhesive 14. The needle 11 is inserted between adjacent teeth for imaging, emitting light. The needle 11 has a hollow structure, and its outer diameter is preferably 0.8 mm. The sheath 12 is installed inside the needle 11, and its outer diameter is smaller than the inner diameter of the needle 11. The sheath 12 is a transparent hard capillary glass tube, and its inner diameter is preferably 0.3 mm, and its outer diameter is 0.42 mm. The optical path assembly 13 is fixedly installed inside the sheath 12 to achieve total internal reflection. The fixing adhesive 14 encapsulates the sheath 12 inside the needle 11, fixing the sheath 12 and the needle 11 together and isolating them from biological erosion. The fixative 14 is preferably epoxy resin commonly used in oral medicine. Epoxy resin is transparent and does not affect light transmission. The fixative 14 can also be other transparent materials.

[0028] The tip of the needle 11 is a pointed end, which has an opening 111, a first oblique surface 112, and a second oblique surface 113. The opening 111 is an oblique cut, and the end of the sheath 12 is located at the opening 111, allowing light to be emitted from the needle hole of the needle 11 for imaging. The first oblique surface 112 is located at the opening 111, and the second oblique surface 113 is located on the opposite side of the opening 111. The front ends of the first oblique surface 112 and the second oblique surface 113 are close to each other and intersect to form a pointed tip. The inclination angle of the first oblique surface 112 is greater than that of the second oblique surface 113. The first oblique surface 112 is formed by encapsulating the opening 111 with the fixing adhesive 14. The first oblique surface 112 can be a single line or composed of multiple zigzag lines, reducing the volume of the needle 11 and making it easier to insert the needle 11 between the two teeth. The needle 11 can be an injection needle or other hollow needles with a pointed end and the opening 111.

[0029] Please combine Figure 1 and Figure 2 The optical path assembly 13 includes a single-mode fiber 131, a coreless fiber 132, and a spherical lens 133. Laser light is emitted from the single-mode fiber 131. One end of the single-mode fiber 131 is fused to the coreless fiber 132, and the other end of the coreless fiber 132 is fused to the spherical lens 133. The spherical lens 133 is a coreless fiber spherical lens. The coreless fiber 132 acts as an optical spacer between the single-mode fiber 131 and the spherical lens 133 to expand the laser beam. The spherical lens 133 is surface-polished at a 48° angle to deflect the incident beam and focuses the emitted beam through a curved end face. The emitted beam exits from the opening 111.

[0030] The length of the coreless optical fiber 132 and the radius of curvature r of the spherical lens 133 are variable parameters that can be set according to actual needs. These parameters are used to quantitatively analyze the working distance and focused spot diameter, and the desired parameters are selected based on the relationship curve. The radius of curvature r of the spherical lens 133 can be a standard size of 0.16 mm. Figure 3 and Figure 4 The graphs show the relationship between the length of the coreless optical fiber 132 and the working distance and the focused spot when the radius of curvature r of the spherical lens 133 is 0.16 mm.

[0031] like Figure 3 As shown, Figure 3 When the radius of curvature r of the spherical lens 133 is 0.16 mm, the relationship between the length of the coreless optical fiber 132 and the working distance is shown in the graph. As the length of the coreless optical fiber 132 increases, the working distance first decreases, then gradually increases to a maximum value, and finally decreases to a stable value.

[0032] like Figure 4 As shown, Figure 4 The graph shows the relationship between the length of the coreless optical fiber 132 and the diameter of the focused spot when the radius of curvature r of the spherical lens 133 is 0.16 mm. When the radius of curvature of the spherical lens 133 is constant, the diameter of the focused spot first increases and then decreases with the increase of the length of the coreless optical fiber.

[0033] Because the working distance of the OCT needle probe needs to be greater than 1mm and the focused spot diameter needs to be less than 25μm, according to Figure 3 and Figure 4 It is known that the length of the coreless optical fiber 132 is preferably 0.53 mm. The specific working distance and focusing spot diameter can be adjusted according to actual needs to select the optimal length of the coreless optical fiber 132.

[0034] Please refer to Figure 5 and Figure 6 , Figure 5 and Figure 6 This is an intensity map of a tooth image taken by the OCT needle probe 1 in actual use. For example... Figure 5 As shown, Figure 5 The image shows the intensity of an image of a healthy tooth sample taken by the OCT needle probe 1. The image reveals the intact enamel structure and the absence of cavities on the tooth surface. Figure 6 As shown, Figure 6 The image shows the intensity of an image of a tooth sample with proximal caries created by the OCT needle probe 1. The image clearly shows the enamel structure and caries cavities, with the arrows pointing to the caries cavities.

[0035] The OCT needle probe of this invention can clearly image biological tissues such as the proximal surfaces of teeth through beam expansion of coreless optical fiber, total reflection of spherical lens and needle opening, effectively realizing the early detection of proximal caries; moreover, the OCT needle probe is simple to manufacture, small in size and easy to hold, which greatly facilitates the clinical operation of doctors.

[0036] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. An OCT needle probe, characterized in that, include, The needle is hollow and has an opening at its tip, which is a beveled cut. The optical path assembly is installed inside the needle and its end is located at the opening.

2. An OCT needle probe as described in claim 1, characterized in that, The needle also includes a first bevel and a second bevel. The first bevel is located at the opening, and the second bevel is located on the opposite side of the opening. The front ends of the first bevel and the second bevel are close to each other and intersect to form a tip. The inclination angle of the first bevel is greater than that of the second bevel.

3. An OCT needle probe as described in claim 2, characterized in that, The first oblique cut surface is a single line or multiple broken lines.

4. An OCT needle probe as described in claim 3, characterized in that, It includes a fixative adhesive that encapsulates the optical path component within the needle tip, and the first beveled surface is formed by the fixative adhesive encapsulating the opening.

5. An OCT needle probe as described in claim 1, characterized in that, The optical path assembly includes a single-mode fiber, a coreless fiber, and a spherical lens. The two ends of the coreless fiber are respectively connected to the single-mode fiber and the spherical lens, and the spherical lens is located at the opening.

6. An OCT needle probe as described in claim 5, characterized in that, The spherical lens is surface-polished at a 48° angle.

7. An OCT needle probe as described in claim 6, characterized in that, The radius of curvature of the spherical lens is 0.16 mm, and the length of the coreless optical fiber is 0.53 mm.

8. An OCT needle probe as described in claim 1, characterized in that, It also includes a sheath, which is fixed inside the needle, and the optical path assembly is installed inside the sheath.

9. An OCT needle probe as described in claim 8, characterized in that, The sheath is a glass tube.

10. An OCT needle probe as described in claim 8, characterized in that, The inner diameter of the sheath is 0.3 mm and the outer diameter is 0.42 mm.

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