Positioner for front section of eyeball

Abstract

The invention discloses an eyeball front section positioner which comprises a concentric ring, a plurality of connecting plates distributed on the concentric ring at equal intervals and two fixing belts arranged on the two sides of the concentric ring respectively. The concentric ring comprises a reference ring, and a middle ring and an inner ring which are sequentially arranged in the reference ring in a sleeving manner; the connecting plates are distributed on a plane formed by the reference ring, the middle ring and the inner ring at equal intervals; the two fixing bands are respectively arranged on two sides of the outer edge of the reference ring; by designing the locator of a hemispherical net structure, the fitness between the locator and the ocular surface of a patient can be improved, the fixing band is stable to wear, the structure is simple, operation is easy, the locator can adapt to patients with different eyeball sizes, and the locator is suitable for diagnosis and treatment scenes of various eye injuries and tumors; meanwhile, the positioner is made of a medical pure titanium material, can be compatible with CT and nuclear magnetic examination at the same time, does not interfere with image quality, can clearly develop positioning marks, and solves the technical problem that a traditional instrument cannot adapt to double-imaging examination.

Description

Technical Field

[0001] This invention relates to the field of ophthalmic medical positioning device technology, specifically to an anterior segment eyeball positioner. Background Technology

[0002] In the diagnosis and treatment of ocular diseases such as intraocular foreign body injuries, ocular lacerations, and ocular tumors, accurately determining the intraocular location, size, and corresponding area on the ocular surface of the foreign body / lesion is a core prerequisite for surgical incision planning and operative path selection. Currently, while CT and MRI scans can provide a general understanding of the intraocular target, there is a lack of dedicated positioning instruments compatible with imaging examinations. Traditional manual marking relies on the surgeon's experience, resulting in significant errors and potentially leading to increased surgical trauma, residual foreign bodies, or incomplete lesion removal. The circular fixation devices used in surgeries such as corneal transplantation can only fix the eye and lack positioning marking functionality; moreover, many of their materials are incompatible with MRI scans, making it impossible to achieve precise positioning in conjunction with imaging.

[0003] In existing technologies, although metal materials may be visible in CT scans, most metals interfere with the magnetic field of MRI, leading to image distortion and even safety risks; conventional medical plastics are difficult to be clearly visible in CT and MRI scans, making it impossible to achieve imaging matching between positioning markers and intraocular targets.

[0004] Therefore, there is an urgent need for a device that is compatible with CT and MRI, can clearly visualize images, and can provide precise positioning markers to solve the problem of the disconnect between "imaging positioning" and "ocular surface marking". Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides an anterior segment ocular locator compatible with CT and MRI scans. By adapting to the imaging materials used in imaging examinations, it achieves a diagnostic and treatment process of "imaging scan without a locator → imaging scan with a locator → precise matching and positioning." The location, size, and corresponding area of ​​the intraocular foreign body / lesion can be accurately predicted before surgery, providing data support for surgical decisions, reducing surgical risks, and improving diagnostic and treatment accuracy.

[0006] The technical solution of this invention is as follows: an anterior segment eye locator, comprising a concentric ring, several connecting plates equidistantly distributed on the concentric ring, and two fixing straps respectively disposed on both sides of the concentric ring; the concentric ring includes a reference ring and an intermediate ring and an inner ring sequentially nested inside the reference ring; the radius difference between the reference ring, the intermediate ring, and the inner ring is 2~4mm; each connecting plate is equidistantly distributed on the plane formed by the reference ring, the intermediate ring, and the inner ring; the reference ring, the intermediate ring, the inner ring, and the connecting plates form a hemispherical mesh structure, and the reference ring, the intermediate ring, the inner ring, and the connecting plates are made of medical-grade pure titanium material; the two fixing straps are respectively disposed on both sides of the outer edge of the reference ring; Furthermore, scale markings are provided on the reference ring, intermediate ring, inner ring, and connecting plate; Note: When the locator is fixed to the surface of the patient's eyeball, the scale markings facilitate the measurement of the size of the foreign body / lesion in the patient's eye.

[0007] Furthermore, the connection points between the connecting plate and the reference ring, intermediate ring, and inner ring are all marked with identification codes by laser engraving; Note: Each identification code corresponds to a fixed spatial location, which helps improve the accuracy of locating foreign bodies / lesions in the patient's eye.

[0008] Furthermore, it also includes an auxiliary frame connected to the fixing strap; the auxiliary frame includes a fixed base, an elastic strap connected to the fixed base, an L-shaped adjusting plate slidably engaged with the fixed base, and a pushing assembly movably disposed on the L-shaped adjusting plate; the fixed base has an arc-shaped groove on the side near the elastic strap; a telescopic plate is slidably engaged with the L-shaped adjusting plate, and a positioning screw is threadedly connected to the L-shaped adjusting plate, capable of engaging with the fixed base and the telescopic plate respectively; the pushing assembly includes a guide cylinder horizontally penetrating the telescopic plate, a pushing rod slidably engaged with the inside of the guide cylinder near the fixed base, and a pushing screw threadedly connected to the guide cylinder and rotatably engaged with the pushing rod; a U-shaped frame is disposed on the side of the pushing rod away from the pushing screw; the two fixing straps are movably connected to the two branches of the U-shaped frame respectively; Instructions: When using, use the elastic strap to fix the fixation base to the patient's head, then adjust the position of the L-shaped adjustment plate on the fixation base and adjust the height of the telescopic plate so that the pushing component is facing the patient's affected eyeball. Then, open the patient's eyelids, rotate the pushing screw to move the pushing rod inside the guide cylinder, and push the locator toward the patient's eyeball. Use the grid on the locator to locate the position of the foreign body / lesion in the patient's eye.

[0009] Furthermore, rollers are rotatably engaged on both branches of the U-shaped frame; the two fixing straps are respectively wound and fixed to the two rollers one by one; Explanation: By wrapping the fixation strap around the roller, the strap is kept taut at all times, which helps to improve the fit between the locator and the patient's eyeball, thereby improving the accuracy of locating foreign bodies / lesions in the patient's eye.

[0010] Furthermore, eyelid support assemblies are provided at both the upper and lower ends of the guide cylinder; the guide cylinder is slidably engaged with the telescopic plate, and a rotating threaded sleeve that is threadedly connected to the guide cylinder is rotatably engaged on the telescopic plate; the eyelid support assembly includes a support rod movably hinged to the side wall of the guide cylinder, an arc-shaped guide plate provided on the side wall of the guide cylinder and slidably engaged with the support rod, and an eyelid support block movably hinged to the end of the support rod; an arc-shaped guide groove is provided through the arc-shaped guide plate, and an operating rod that is slidably engaged with the arc-shaped guide groove is provided on the support rod; Instructions: When using, rotate the threaded sleeve to move the guide cylinder along the telescopic plate, so that the eyelid support blocks at the ends of the two support rods contact the patient's upper and lower eyelids respectively; then, use the operating lever to slide the support rods on the arc-shaped guide plate and open the patient's eyelids.

[0011] Furthermore, the operating lever is hollow inside, and a locking lever is slidably engaged inside the operating lever; the operating lever is rotatably engaged with the support rod, and a small gear is connected to the end of the operating lever; a locking gear ring connected to the locking lever is sleeved on the outside of the operating lever; an arc-shaped rack that meshes with the small gear and a locking rack that meshes with the locking gear ring are provided on the inner side of the arc-shaped guide groove; and compression springs that abut against the locking gear ring and the support rod are sleeved on the outside of the operating lever. Instructions: When in use, pull the locking rod outward to disengage the locking gear ring from the locking rack. Then rotate the operating rod. The engagement of the pinion and the arc-shaped rack allows the support rod to move stably on the arc-shaped guide plate, which improves the safety of the invention. At the same time, when the locking gear ring engages with the locking rack under the action of the compression spring, it can fix the position of the support rod on the arc-shaped guide plate.

[0012] Furthermore, an extension plate is slidably engaged on the side of the eyelid support block away from the arc-shaped guide plate, and a slide is provided at the bottom of the eyelid support block. The extension plate is slidably engaged with the slide via a slider, and a return spring is provided inside the slide to abut against the slider. A change guide wheel is rotatably engaged inside the eyelid support block, and a traction guide wire is wound around the operating rod, passing through the change guide wheel and connecting to the extension plate. Note: During the rotation of the operating lever, the guide wire is pulled, and at this time the extension plate slides out from the bottom of the eyelid support block, thereby increasing the contact area between the eyelid support block and the patient's eyelid and improving the reliability of the invention.

[0013] Furthermore, a wedge-shaped cut-in portion is provided at the end of the extension plate; Note: By setting a wedge-shaped cutting part at the end of the extension plate, the resistance when the extension plate is inserted between the patient's eyeball and eyelid can be effectively reduced.

[0014] The method of using this invention is as follows: First, perform imaging scans without a locator: the patient does not wear a locator and completes CT and MRI examinations. The imaging reports clarify the preliminary location, size, and three-dimensional coordinates of the intraocular foreign body / lesion. Then, imaging scans with the locator are performed: the patient wears the locator, and the fixing strap is adjusted so that the center of the locator is aligned with the center of the cornea and the curved surface is in close contact with the ocular surface. CT and MRI examinations are performed again to identify the location of the foreign body / lesion in the patient's eye and the corresponding location of the identification code. Then, precise matching and positioning: compare the two scan images, map the three-dimensional coordinates of the intraocular foreign body / lesion with the identification code of the locator, determine the ocular surface positioning code and region corresponding to the foreign body / lesion, and at the same time, estimate the actual size of the foreign body / lesion through the scale markings of the locator in the image; Finally, ocular surface marking and surgical application: Based on the matching results, the ocular surface mapping position of the corresponding coded point on the locator is marked with a sterile marking pen; during the operation, the surgeon can accurately plan the incision and operation path based on the ocular surface marking and preoperative imaging data, and carry out surgeries such as foreign body removal, laceration repair or tumor excision.

[0015] Compared with the prior art, the beneficial effects of the present invention are reflected in the following aspects: First, this invention improves the fit between the locator and the patient's ocular surface by designing a hemispherical mesh structure locator. The fixation strap is stable to wear, the structure is simple and easy to operate, and it can be adapted to patients with different eyeball sizes. It is suitable for various ocular injuries and tumor treatment scenarios. At the same time, the locator is made of medical-grade pure titanium material, which can be compatible with CT and MRI examinations. It does not interfere with image quality and can clearly visualize the positioning mark, thus solving the technical problem that traditional instruments cannot be adapted to dual imaging examinations. Secondly, this invention achieves precise correspondence between intraocular targets and ocular surface markings through the "two-scan + identification code matching" mode, with an error significantly lower than that of manual marking, especially meeting the need for precise positioning of foreign bodies in the anterior segment; moreover, the size of the foreign body / lesion can be estimated through the scale markings of the locator, providing data support for preoperative surgical planning and instrument selection, and reducing the difficulty of intraoperative decision-making. Third, the present invention uses an auxiliary frame to fix the locator to the patient's ocular surface, which helps to improve the stability of the locator in use; moreover, by designing an eyelid support component, it can create favorable conditions for the use of the locator and improve work efficiency. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the positioner of the present invention; Figure 2 This is a schematic diagram showing the connection between the positioner and the auxiliary frame of the present invention; Figure 3 This is a schematic diagram showing the connection between the L-shaped adjusting plate and the fixed base of the present invention; Figure 4 This is a schematic diagram showing the connection between the pushing component and the positioner of the present invention; Figure 5 This is a schematic diagram of the connection between the U-shaped frame and the fixing strap of the present invention; Figure 6 This is a schematic diagram of the connection between the eyelid support block and the support rod of the present invention; Figure 7 This is the present invention. Figure 6 A magnified view of a portion of point A in the middle; Figure 8 This is a schematic diagram showing the connection between the locking rod and the operating rod of the present invention; Figure 9 This is a schematic diagram showing the connection between the extension plate and the eyelid support block of the present invention; Figure 10 This is a schematic diagram of the connection between the guide wire and the extension plate of the present invention; Among them, 1-concentric ring, 10-reference ring, 11-intermediate ring, 12-inner ring, 2-connecting plate, 3-fixing strap, 4-auxiliary frame, 40-fixed seat, 400-arc groove, 41-elastic strap, 42-L-shaped adjusting plate, 420-telescopic plate, 43-pushing assembly, 430-guide cylinder, 431-pushing rod, 432-pushing screw, 433-U-shaped frame, 4330-roller, 434-rotating threaded sleeve, 5-eyelid Support assembly, 50-support rod, 51-arc guide plate, 510-arc guide groove, 52-eyelid support block, 520-slide rail, 521-reset spring, 522-reversing guide wheel, 53-operating lever, 530-pinion, 54-locking rod, 540-locking gear ring, 541-compression spring, 55-arc rack, 56-locking rack, 57-extension plate, 570-slider, 571-wedge-shaped cutting part, 58-traction guide wire. Detailed Implementation

[0017] Example 1 like Figure 1 The anterior segment locator shown includes a concentric ring 1, 12 connecting plates 2 equidistantly distributed on the concentric ring 1, and two fixing straps 3 respectively disposed on both sides of the concentric ring 1. The concentric ring 1 includes a base ring 10 and an intermediate ring 11 and an inner ring 12 sequentially nested inside the base ring 10. The radius difference between the base ring 10, the intermediate ring 11, and the inner ring 12 is 2 mm. Each connecting plate 2 is equidistantly distributed on the plane formed by the base ring 10, the intermediate ring 11, and the inner ring 12. The base ring 10, the intermediate ring 11, the inner ring 12, and the connecting plates 2 form a hemispherical mesh structure, and the base ring 10, the intermediate ring 11, the inner ring 12, and the connecting plates 2 are made of medical-grade pure titanium. The two fixing straps 3 are respectively disposed on both sides of the outer edge of the base ring 10. The base ring 10, the intermediate ring 11, the inner ring 12, and the connecting plates 2 are all provided with scale markings. The connection points between the connecting plates 2 and the base ring 10, the intermediate ring 11, and the inner ring 12 are all marked with identification codes by laser engraving.

[0018] In this embodiment, the locator is used as follows: The locator was fixed to the patient's ocular surface using the fixing strap 3, and the center of the locator was aligned with the center of the cornea and the curved surface of the locator was made to fit snugly against the ocular surface. Then, CT and MRI scans were performed to identify the location of the foreign body / lesion in the patient's eye and the corresponding location of the identification code. Then, the three-dimensional coordinates of the foreign body / lesion in the patient's eye were mapped to the identification code of the locator to determine the ocular surface location code and region corresponding to the foreign body / lesion. At the same time, the scale markings on the locator were used to estimate the actual size of the foreign body / lesion. Finally, the location of the foreign body / lesion in the patient's eye was marked using a sterile pen.

[0019] Example 2 The difference between this embodiment and Embodiment 1 is that: like Figure 2 , 3 As shown in Figures 4 and 5, the system also includes an auxiliary frame 4 connected to the fixing strap 3. The auxiliary frame 4 includes a fixed base 40, an elastic strap 41 connected to the fixed base 40, an L-shaped adjusting plate 42 slidably engaged with the fixed base 40, and a pushing assembly 43 movably disposed on the L-shaped adjusting plate 42. The fixed base 40 has an arc-shaped groove 400 on the side near the elastic strap 41. A telescopic plate 420 is slidably engaged with the L-shaped adjusting plate 42, and a positioning screw that can engage with the fixed base 40 and the telescopic plate 422 respectively is threaded onto the L-shaped adjusting plate 42. The pushing assembly 43 includes a horizontal through-type... A guide cylinder 430 is installed on the telescopic plate 420; a push rod 431 is slidably engaged inside the guide cylinder 430 near the fixed seat 40; a push screw 432 is threadedly connected to the guide cylinder 430 and rotatably engaged with the push rod 431; a U-shaped frame 433 is provided on the side of the push rod 431 away from the push screw 432; two fixing straps 3 are movably connected to two branches of the U-shaped frame 433 respectively; rollers 4330 are rotatably engaged on both branches of the U-shaped frame 433; the two fixing straps 3 are respectively wound and fixed to the two rollers 4330 one by one.

[0020] In this embodiment, the locator is used as follows: The fixation base 40 is fixed to the patient's head using the elastic strap 41. Then, the position of the L-shaped adjustment plate 42 on the fixation base 40 is adjusted, and the height of the telescopic plate 420 is adjusted so that the pushing component 43 is facing the patient's diseased eyeball. The patient's eyelid is opened using external instruments, and the pushing screw 432 is rotated so that the pushing rod 431 moves inside the guide cylinder 430, pushing the locator toward the patient's eyeball and aligning the center of the locator with the center of the cornea and the curved surface of the locator against the ocular surface. Then, CT and MRI examinations are performed to locate and mark the position of the foreign body / lesion in the patient's eye.

[0021] Example 3 The difference between this embodiment and Embodiment 2 is that: like Figure 4 , 6As shown in Figure 7, eyelid support assemblies 5 are provided at both the upper and lower ends of the guide cylinder 430; the guide cylinder 430 is slidably engaged with the telescopic plate 420, and a rotating threaded sleeve 434 that is threadedly connected to the guide cylinder 430 is rotatably engaged with the telescopic plate 420; the eyelid support assembly 5 includes a support rod 50 that is movably hinged to the side wall of the guide cylinder 430, an arc-shaped guide plate 51 that is provided on the side wall of the guide cylinder 430 and slidably engaged with the support rod 50, and an eyelid support block 52 that is movably hinged to the end of the support rod 50; an arc-shaped guide groove 510 is provided through the arc-shaped guide plate 51, and an operating rod 53 that is slidably engaged with the arc-shaped guide groove 510 is provided on the support rod 50.

[0022] In this embodiment, the locator is used as follows: The fixation base 40 is fixed to the patient's head using the elastic strap 41. Then, the position of the L-shaped adjustment plate 42 on the fixation base 40 is adjusted, and the height of the telescopic plate 420 is adjusted so that the pushing component 43 is facing the patient's affected eyeball. The rotating threaded sleeve 434 is rotated so that the guide cylinder 430 moves along the telescopic plate 420, and the eyelid support blocks 52 at the ends of the two support rods 50 contact the patient's upper and lower eyelids respectively. Then, the support rods 50 are slid on the arc-shaped guide plate 51 by the operating rod 53, and the patient's eyelids are opened. Then, the pushing screw 432 is rotated so that the pushing rod 431 moves inside the guide cylinder 430, and the locator is pushed towards the patient's eyeball, so that the center of the locator is aligned with the center of the cornea and the curved surface of the locator is in close contact with the ocular surface. Then, CT and MRI examinations are performed to locate and mark the position of the foreign body / lesion in the patient's eye.

[0023] Example 4 The difference between this embodiment and Embodiment 3 is that: like Figure 7 , 8 As shown, the operating lever 53 is hollow inside, and a locking lever 54 is slidably engaged inside the operating lever 53; the operating lever 53 is rotatably engaged with the support rod 50, and a small gear 530 is connected to the end of the operating lever 53; a locking gear ring 540 connected to the locking lever 54 is sleeved on the outside of the operating lever 53; an arc-shaped rack 55 that meshes with the small gear 530 and a locking rack 56 that meshes with the locking gear ring 540 are provided on the inner side of the arc-shaped guide groove 51; and a locking rack 56 that meshes with the locking gear ring 540 is provided on the outside of the operating lever 53; the operating lever 53 is sleeved with a locking gear ring 540 and a support rod 50 respectively. The compression spring 541 engages with the locking ring 540. In use, the locking rod 54 is pulled outward to disengage the locking toothed ring 540 from the locking rack 56. Then, the operating rod 53 is rotated, and the engagement of the pinion 530 with the arc-shaped rack 55 allows the support rod 50 to move stably on the arc-shaped guide plate 51, which helps to improve the safety of the invention. At the same time, when the locking toothed ring 540 engages with the locking rack 56 under the action of the compression spring 541, the position of the support rod 50 on the arc-shaped guide plate 51 can be fixed.

[0024] Example 5 The difference between this embodiment and embodiment 4 is that: like Figure 9 , 10 As shown, an extension plate 57 is slidably engaged with the side of the eyelid support block 52 away from the arc-shaped guide plate 51. A slide rail 520 is provided at the bottom of the eyelid support block 52. The extension plate 57 is slidably engaged with the slide rail 520 via a slider 570. A return spring 521 is provided inside the slide rail 520 to abut against the slider 570. A reversing guide wheel 522 is rotatably engaged inside the eyelid support block 52. A traction guide wire 58 is wound around the operating rod 53, passing through the reversing guide wheel 522 and connecting to the extension plate 57. A wedge-shaped cutting part 571 is provided at the end of the extension plate 57. During the rotation of the operating rod 53, the traction guide wire 58 is pulled, and at this time the extension plate 57 slides out from the bottom of the eyelid support block 52, thereby increasing the contact area between the eyelid support block 52 and the patient's eyelid and improving the reliability of the invention.

Claims

1. An anterior segment eyeball locator, characterized in that, It includes a concentric ring (1), several connecting plates (2) equidistantly distributed on the concentric ring (1), and two fixing straps (3) respectively disposed on both sides of the concentric ring (1); the concentric ring (1) includes a reference ring (10) and an intermediate ring (11) and an inner ring (12) sequentially sleeved inside the reference ring (10); each of the connecting plates (2) is equidistantly distributed on the plane formed by the reference ring (10), the intermediate ring (11) and the inner ring (12); the reference ring (10), the intermediate ring (11), the inner ring (12) and the connecting plates (2) form a hemispherical mesh structure; the two fixing straps (3) are respectively disposed on both sides of the outer edge of the reference ring (10).

2. The anterior segment eyeball locator according to claim 1, characterized in that, The reference ring (10), intermediate ring (11), inner ring (12) and connecting plate (2) are all equipped with scale markings.

3. The anterior segment eyeball locator according to claim 1, characterized in that, The connection points of the connecting plate (2) with the reference ring (10), the intermediate ring (11), and the inner ring (12) are all marked with identification codes by laser engraving.

4. The anterior segment eyeball locator according to claim 1, characterized in that, It also includes an auxiliary frame (4) connected to the fixing strap (3); the auxiliary frame (4) includes a fixing seat (40), an elastic strap (41) connected to the fixing seat (40), an L-shaped adjusting plate (42) slidably engaged with the fixing seat (40), and a pushing component (43) movably disposed on the L-shaped adjusting plate (42); the fixing seat (40) has an arc-shaped groove (400) on the side near the elastic strap (41); a telescopic plate (420) is slidably engaged with the L-shaped adjusting plate (42), and the L-shaped adjusting plate (42) is threadedly connected to a component capable of being respectively engaged with the fixing seat (40). The telescopic plate (420) is engaged with a positioning screw; the pushing assembly (43) includes a guide cylinder (430) horizontally penetrating the telescopic plate (420), a push rod (431) slidably engaged inside the guide cylinder (430) near the fixed seat (40), and a push screw (432) threadedly connected to the guide cylinder (430) and rotatably engaged with the push rod (431); a U-shaped frame (433) is provided on the side of the push rod (431) away from the push screw (432); the two fixing straps (3) are respectively movably connected to the two branches of the U-shaped frame (433).

5. The anterior segment eyeball locator according to claim 4, characterized in that, The guide cylinder (430) is provided with eyelid support components (5) at both the upper and lower ends; the guide cylinder (430) is slidably engaged with the telescopic plate (420), and the telescopic plate (420) is rotatably engaged with a rotating threaded sleeve (434) that is threadedly connected to the guide cylinder (430); the eyelid support component (5) includes a support rod (50) movably hinged to the side wall of the guide cylinder (430), an arc-shaped guide plate (51) provided on the side wall of the guide cylinder (430) and slidably engaged with the support rod (50), and an eyelid support block (52) movably hinged to the end of the support rod (50); an arc-shaped guide groove (510) is provided through the arc-shaped guide plate (51), and an operating rod (53) is provided on the support rod (50) that is slidably engaged with the arc-shaped guide groove (510).

6. The anterior segment eyeball locator according to claim 5, characterized in that, The operating lever (53) is hollow inside, and a locking lever (54) is slidably engaged inside the operating lever (53); the operating lever (53) is rotatably engaged with the support rod (50), and a small gear (530) is connected to the end of the operating lever (53); a locking tooth ring (540) connected to the locking lever (54) is sleeved on the outside of the operating lever (53); an arc-shaped rack (55) that meshes with the small gear (530) and a locking rack (56) that meshes with the locking tooth ring (540) are provided on the inner side of the arc-shaped guide groove (51); a compression spring (541) that abuts against the locking tooth ring (540) and the support rod (50) is sleeved on the outside of the operating lever (53).

7. The anterior segment eyeball locator according to claim 5, characterized in that, An extension plate (57) is slidably engaged on the side of the eyelid support block (52) away from the arc-shaped guide plate (51). A slide rail (520) is provided at the bottom of the eyelid support block (52). The extension plate (57) is slidably engaged with the slide rail (520) through a slider (570). A return spring (521) is provided inside the slide rail (520) to abut against the slider (570). A change guide wheel (522) is rotatably engaged inside the eyelid support block (52). A traction guide wire (58) is wound around the operating rod (53) and passes through the change guide wheel (522) and connects to the extension plate (57).

8. The anterior segment eyeball locator according to claim 1, characterized in that, The reference ring (10), intermediate ring (11), inner ring (12) and connecting plate (2) are all provided with scale lines.

Images