Ophthalmic medical instrument with illuminated snare

Abstract

To provide an ophthalmic device for severing a lens of an eye in which a wire forming a snare does not need to be hollow.SOLUTION: An ophthalmic surgical instrument for severing a lens of an eye has an elongated shaft and a snare formed by a wire extending along the elongated shaft and having a looped segment that moves between contracted and dilated configurations. When the shaft is inserted through the pupil and the looped segment is placed around the lens, a bottom portion of the looped segment engages and severs a bottom portion of the lens upon moving toward the contracted configuration. A light-conducting element extends along at least a portion of a length of the looped segment, and a light source is in communication with the light-conducting element, so that light from the light source travels through the element and illuminates at least a portion of the length of the looped segment. The light-conducting element may be a tube surrounding the wire, or may be a solid filament extending adjacent the wire.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to an ophthalmic medical device including a snare for facilitating the removal of a patient's lens during cataract surgery. In particular, the present invention relates to a medical device having a snare illuminated via a light guide tube surrounding the snare.

Background Art

[0002] Snare devices have been used to bisect a patient's lens during cataract surgery to facilitate removal of the lens. This device generally takes the form of an elongated shaft and includes a wire extending from or near the distal end of the shaft. The wire is arranged around the lens and is in the form of a loop that then contracts, whereby the wire can cut the lens and the cut lens can be more easily removed from the surrounding lens capsule. One problem with conventional snare devices is that it is difficult for the surgeon to see the wire behind the lens, making accurate placement difficult and the surgery challenging. One attempt to make the wire snare more visible is described in Patent Document 1, the disclosure of which is incorporated herein by reference. In this device, the wire is configured to be hollow and the light source communicates with the lumen of the wire. The opening of the wire at a point located behind the lens allows light to leak. This light can be seen through the lens and identifies the position of the wire to the surgeon.

[0003] One drawback of this configuration is that it is expensive and cumbersome to manufacture and assemble a wire with a light source. Further, the wire has to be made larger to accommodate the lumen and is therefore not effective when cutting the lens during use. Since such devices are generally not reused, it is desirable to provide a lens cutting device that is simple and inexpensive to manufacture and effective and reliable in use.

Prior Art Documents

Patent Documents

[0004] [Patent Document 1] U.S. Patent No. 10,485,700 [Overview of the project] [Problems that the invention aims to solve]

[0005] Therefore, an object of the present invention is to provide an ophthalmic device for cutting the lens of a crystalline lens in which the wire forming the snare does not need to be hollow. [Means for solving the problem]

[0006] This objective is achieved by an ophthalmic surgical instrument for cutting the lens of the eye, comprising an elongated shaft having a distal end portion and a snare formed by a wire extending along the elongated shaft and having a loop-shaped segment, the loop-shaped segment being positioned adjacent to the distal end portion and configured to move between a contracted and expanded form, and the loop-shaped segment having a diameter approximating the diameter and shape of the lens of the eye. When the elongated shaft is inserted through the pupil and the loop-shaped segment is positioned around the lens, the bottom of the loop-shaped segment is configured to engage with the bottom of the lens and cut it as it moves toward the contracted form. This allows the surgeon to remove the lens more easily during surgery.

[0007] To enable the surgeon to visualize the loop-shaped segment after it has been positioned around the lens, the apparatus according to the present invention also includes a light guide element adjacent to at least a portion of the length of the loop-shaped segment and a light source communicating with the light guide element, configured such that light from the light source travels through the light guide element and illuminates at least a portion of the length of the loop-shaped segment. The light from the light source travels through the material of the light guide element and exits from the distal end of the light guide element. This distal end can be positioned at any point along the loop-shaped segment, but is preferably located behind the lens during surgery and preferably in the center of the lens. The point where the light exits from the end of the light guide element forms a bright spot that can be seen through the lens during cataract surgery, thus ensuring proper positioning of the snare formed by the loop-shaped segment.

[0008] In one embodiment, the light guide element is in the form of a solid filament running adjacent to the wire.

[0009] In another embodiment, the light guide element is in the form of a tube surrounding the wire. The tubular structure surrounding the wire creates a larger surface area for light emission compared to a single strand, and therefore increases the visibility of the snare in use.

[0010] In a further embodiment, the entire light guide element is semi-transparent or transparent, so that light also exits along the length of the light guide element, illuminating the entire range of the loop-shaped segment. In this situation, the light guide element may extend along the entire length of the loop-shaped segment so that the entire snare is illuminated during surgery. In this embodiment where the light guide element is a tube, the tube is configured to have a sufficiently small diameter so that cutting the lens still functions during wire contraction.

[0011] The light guide element is preferably made of polyurethane, but any other suitable transparent, translucent, or opaque flexible material that scatters light can also be used.

[0012] In another embodiment, the light guide element and wires can be covered with an opaque covering so that light from the light source is visible only at the ends of the light guide element. In this embodiment, the ends of the light guide element must be positioned behind the lens during surgery, as they are the only areas where light is visible. Additionally, openings can be provided along the length of the covering for additional bright spots, if desired.

[0013] Opaque coverings can be made from metal, plastic, or any other suitable material. The covering can be woven, braided, coiled, painted, laminated, or any suitable structure that allows movement of the tubes and wires during shrinking and expanding.

[0014] The wire is preferably made of nitinol and has shape memory properties so that the elliptical shape of the loop-shaped segment is maintained throughout use. Other suitable materials may also be used. In one embodiment, the loop-shaped portion of the wire has a bend at the bottom of the loop. When the light guide element terminates at the bend, the end of the light guide element faces the shaft, and therefore the light emanating from the light guide element is guided to pass through the lens and return to the surgeon, providing maximum visibility.

[0015] In a preferred embodiment, the device includes a housing connected to an elongated shaft. The housing has an actuator connected to a wire, configured to move the wire between a retracted and an expanded configuration. Preferably, the light source is located within the housing, and the light guide element extends through the elongated shaft into the housing, where it is connected to the light source. In another embodiment, the light source is located outside the housing, and the light guide element extends through the housing from the housing to the external light source.

[0016] The actuator can take any suitable form. In one embodiment, the actuator is formed by a sliding element positioned in a slot within the housing. By sliding the sliding element away from the distal end of the elongated shaft, the wire is moved to a retracted position, causing the wire to cut the lens, and by sliding the sliding element toward the distal end of the elongated shaft, the wire is moved to an expanded position, making it usable.

[0017] The light source can be formed by any suitable light source, such as a light-emitting diode (LED). If the light source is located within a housing, it is preferable that it be powered by a battery located within the housing so that the instrument is portable and does not require a wired connection to a power source. Alternatively, the light source can be located remotely from the surgical instrument, and a tube can extend through the instrument to the light source.

[0018] Other objects and features of the present invention will become apparent from the following detailed description, which will be considered in conjunction with the accompanying drawings. However, it should be understood that these drawings are designed for illustrative purposes only and not to define the limitations of the present invention. [Brief explanation of the drawing]

[0019] [Figure 1] This is a side view of an ophthalmic surgical instrument according to the present invention. [Figure 2] This figure shows the device with the housing cover removed. [Figure 3] This is an exploded view of the device. [Figure 4] This is a cross-sectional view of the device along line IV-IV in Figure 1. [Figure 5] This figure shows an alternative embodiment of a snare drum. [Figure 6] This figure shows an alternative embodiment of the device equipped with an external light source. [Figure 7] This figure shows another alternative embodiment of the present invention. [Figure 8]It is an enlarged view of the circle 8 in FIG. 7. [Figure 9] It is a diagram showing another alternative embodiment of the present invention. [Figure 10] It is a diagram showing a further embodiment of the present invention.

Mode for Carrying Out the Invention

[0020] In the drawings, like reference numerals indicate like elements throughout several views. Referring to the drawings, FIGS. 1 - 3 show an ophthalmic surgical instrument 1, which includes a housing 10, an elongated shaft 20 in the form of a needle having a distal end 21, an opening 22 in its side wall, and a snare 30 formed by a wire for cutting lens tissue. The elongated shaft 20 is sized to pass through a corneal incision and has a proximal end portion 23, which may be integrally formed with or attached to the housing 10 or the slider cartridge 40 shown in FIG. 2.

[0021] The snare 30 of the ophthalmic surgical instrument 1 is movable within the elongated shaft 20 via an actuating mechanism formed by a slider cartridge 40 and a slider button 45 within a channel 41 of the slider cartridge 40. The slider cartridge 40 is accessible through an opening 15 of the housing 10. The first end of the snare 30 is connected to the slider button 45 as shown in FIG. 4, the second end of the snare 30 is fixed within the housing, and by moving the slider button 45 along the channel 41, the loop-shaped segment 33 formed by the snare 30 can be expanded or retracted. By retracting the loop-shaped segment 33 by sliding the slider button 45 away from the distal end 22, the snare 30 enables the lens disposed within the loop-shaped segment 33 to be bisected during surgery.

[0022] The snare 30 is made from a flexible metallic material, such as nickel-titanium or any other suitable superelastic material. The snare may also be made from any suitable ductile material. Surrounding the snare 30 is a light guide tube 50 that extends at least partially around the loop-shaped segment 33. In the embodiments shown in Figures 1-4, the light guide tube 50 terminates at a distal end 51 located at the bottom of the loop-shaped segment 33. As shown in Figure 4, the light guide tube 50 extends around the top of the loop-shaped segment 33, enters the elongated shaft 20 together with the snare 30, extends through the slider cartridge 40 and connects to a light source 60 located within the housing 10. The light source 60 can be connected to a power source 70, such as a battery, also located within the housing 10, so that the ophthalmic surgical instrument 1 is fully portable and wireless.

[0023] The light source 60 may be a light-emitting diode (LED), a small fluorescent lamp, an incandescent bulb, or any other suitable light source. The light source 60 is in communication with the light guide tube 50 so that light from the light source is emitted from the light guide tube and from the distal end 51. The light guide tube 50 is preferably made of a flexible, translucent material such as polyurethane so that light is emitted along the length of the light guide tube 50 and is visible along its entire length. In this embodiment, the light will also appear as a bright spot at the exit of the distal end 51. In another embodiment, the light guide tube 50 is made of an opaque material or is covered with an opaque coating or sheath so that only the light emitting from the distal end 51 is visible. In one embodiment, the light guide tube 50 can be covered with a metal coating.

[0024] In use, the elongated shaft 20 is inserted through the corneal incision and the anterior capsulotomy (capsulorhexis), and the distal end portion 21 is positioned around the surface of the lens L. The surgeon can use the light emitted from the light guide tube 50 to properly position the snare 30 relative to the lens L. With the loop-shaped segment 33 in the selected position, confirmed using the light emitted from the bottom 51 of the light guide tube 50, the loop-shaped segment 33 transitions from an expanded form to a contracted form, thereby cutting the lens L.

[0025] Figure 5 shows an alternative embodiment of the present invention, in which the device 100 has an elongated shaft 200 with an opening 220 through which a snare 300 formed by wire extends into a loop-shaped segment 330. The snare 300 is completely enclosed in a light guide tube 500 connected to a light source 600, as described above with respect to Figures 1-4. The light guide tube 500 is transparent or translucent so that light from the light source 600 can be seen along the entire length of the snare. The light guide tube 500 is thin enough so that the snare 300 enclosed by the light guide tube 500 can still be moved to the retracted position (using the same slider mechanism as described above), as described above with respect to Figures 1-4.

[0026] Figure 6 shows another alternative embodiment, in which the light source 660 is located outside the housing 10 of the ophthalmic surgical instrument 1. The snare 350, surrounded by the light guide tube 550, penetrates the housing completely and extends to a remote light source 660, which may be located on a remote device or independently. This embodiment allows for the use of a larger, more powerful light source and a larger power supply than those available for placement inside the housing 10.

[0027] Alternative embodiments of the present invention are shown in Figures 7 and 8. Here, a light guide element in the form of a solid filament 5500 extends parallel to the snare 3000 and terminates at the midpoint of a loop-shaped segment 3300 of the snare 3000. A coiled cover 4400 surrounds the snare 3000 and the filament 5500, bringing these two components together. The cover 4400 can be formed of a metal wire, or any other suitable material such as a polymer, or any other suitable mixed material. In this embodiment, light from the filament 5500 exits from the end 5510 and forms a bright spot behind the lens during surgery, as described above with respect to Figures 1-4. The filament 5500 is connected to a light source, which is located inside or away from the housing 10, as disclosed with respect to the embodiments of Figures 1-6.

[0028] Figure 9 shows a further embodiment of the present invention, which is identical to the embodiments of Figures 7 and 8, using the apparatus of Figures 1-6, except that in this case the cover 8000 is made of a woven material, usually in the form of a metal tape or thread. However, any other suitable material may be used as well. It is also conceivable that the cover be made of a solid tube or molded material that covers both the snare 3000 and the filament 5500.

[0029] Further embodiments are shown in Figure 10, where the ophthalmic surgical instrument 1 is identical to the instrument shown in Figures 1-4, except that the snare 30 is bent in two opposite directions at the bottom of the loop-shaped portion 33, forming a Z-shape or S-shape, and the intermediate portion 340 between the bent portions 341 and 342 extends diagonally toward the elongated shaft 20 toward the extent of the loop-shaped portion 33. The light guide tube 50 terminates at the intermediate portion 340 so that its distal end 51 is directed toward the elongated shaft 20. Thus, the bright spot formed by the light exiting the light guide tube 50 is directed toward the surgeon during surgery (along arrow A), and is therefore easier to see, even when viewing through a lens that is substantially opaque in cataracts. The snare of Figure 10 can also be used in embodiments in which the light guide element is in the form of a solid filament, as shown by the filament 5500 in Figures 7-9. In either case, the end of the light guide element is turned back toward the elongated shaft 20, and the brightest part of the device is directed toward the surgeon, thus making the snare more visible behind the lens. The light guide element may be covered or coated so that light is visible only at the end 51, as shown in embodiments of Figures 7-9, or it may not be covered at all along the range of the light guide element, i.e., the light guide tube 50, so that light is visible.

[0030] Although only a few embodiments of the present invention have been described above, it is clear that many changes and modifications can be made without departing from the spirit and scope of the present invention.

Claims

1. 1. An ophthalmic surgical instrument for cutting the lens of the eye, comprising: an elongate shaft having a distal end portion; a wire extending along the elongate shaft and having a looped segment disposed adjacent the distal end portion and configured to move between a contracted configuration and an expanded configuration, the looped segment exhibiting a diameter approximating the diameter and shape of a lens of the eye, the looped segment having a base configured to engage a base of the lens and cut the lens when the looped segment is disposed around the lens and moves toward the contracted configuration; a light-guiding element extending along at least a portion of the length of the looped segment; a light source in communication with the light-guiding element, the light source configured to pass through the light-guiding element and illuminate at least a portion of the length of the looped segment.

2. The ophthalmic surgical instrument of claim 1 , wherein the light-guiding element is translucent.

3. The ophthalmic surgical instrument of claim 2 , wherein the light-guiding element extends along the entire length of the looped segment.

4. The ophthalmic surgical instrument of claim 1 , wherein the light-guiding element terminates at the bottom of the looped segment, and light from the light source exits the light-guiding element at the bottom of the looped segment.

5. The ophthalmic surgical instrument of claim 1 , wherein the light-guiding element is made of polyurethane.

6. 5. The ophthalmic surgical instrument of claim 4, wherein the light-guiding element is opaque or covered with an opaque coating or covering such that light from the light source is visible only at the ends of the light-guiding element.

7. The ophthalmic surgical instrument of claim 1 , wherein the wire is made of nitinol.

8. The ophthalmic surgical instrument of claim 1 , wherein the light-guiding element extends through the elongate shaft.

9. 10. The ophthalmic surgical instrument of claim 1, further comprising a housing connected to the elongate shaft, the housing including an actuator connected to the wire and configured to move the wire between a contracted configuration and an expanded configuration.

10. The ophthalmic surgical instrument of claim 9 , wherein the light source is disposed within the housing.

11. The ophthalmic surgical instrument of claim 9 , wherein the light source is located external to the housing and the tube extends through the housing to the light source.

12. The ophthalmic surgical instrument of claim 9 , wherein the actuator includes a sliding element disposed in a slot in the housing.

13. The ophthalmic surgical instrument of claim 1 , wherein the light source is a light emitting diode (LED).

14. The ophthalmic surgical instrument of claim 9 , wherein the light source is powered by a battery disposed within the housing.

15. The ophthalmic surgical instrument of claim 1 , wherein the light-guiding element is a tube that surrounds the wire.

16. The ophthalmic surgical instrument of claim 1 , wherein the light-guiding element is a solid filament extending adjacent to the wire.

17. The ophthalmic surgical instrument of claim 6 , wherein the light-guiding element and the wire are covered by a covering that is woven or coiled.

18. The ophthalmic surgical instrument of claim 17 , wherein the coating is metallic.

19. The ophthalmic surgical instrument of claim 1 , wherein the wire is bent in two opposite directions approximately midway through the looped segment to form a non-parallel intermediate portion of the looped segment.

20. 20. The ophthalmic surgical instrument of claim 19, wherein the light transmitting element terminates at the intermediate portion of the looped segment such that a distal end of the light transmitting element faces the elongate shaft.

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