Abstract
The pupil expander is used to expand a pupil in ophthalmic surgery and includes a ring portion forming a ring and an iris hooking portion provided to the ring portion. The ring portion includes a first ring portion formed in a shape curved radially inward and a second ring portion formed in a shape curved radially outward, the first ring portion and the second ring portion being arranged alternately along a circumferential direction of the ring portion. The first ring portion is provided with the iris hooking portion. The iris hooking portion is configured to be hooked on a pupillary margin of an iris in a manner such that the first ring portion and the second ring portion are arranged on a front surface side of the iris.
Claims
1. A pupil expander used to expand a pupil in ophthalmic surgery, comprising: a ring portion formed in a ring shape; and an iris hooking portion provided to the ring portion, wherein the ring portion includes a first ring portion formed in a shape curved radially inward and a second ring portion formed in a shape curved radially outward, the first ring portion and the second ring portion being arranged alternately along a circumferential direction of the ring portion, wherein the first ring portion is provided with the iris hooking portion, and wherein the iris hooking portion is configured to be hooked on a pupillary margin of an iris in a manner such that the first ring portion and the second ring portion are arranged on a front surface side of the iris.
2. The pupil expander as recited in claim 1, wherein the ring portion is configured such that an amount of a radially outward movement of the iris hooking portion of the first ring portion other than the first ring portion to which an external force is applied is suppressed to 70% or less of an amount of a radially inward movement of the iris hooking portion of the first ring portion to which the external force is applied.
3. The pupil expander as recited in claim 1, wherein the second ring portion is formed of a material more easily elastically deformable in a radial direction than the first ring portion.
4. The pupil expander as recited in claim 1, wherein the second ring portion is formed, at its inner peripheral portion, with a groove extending in a thickness direction.
5. The pupil expander as recited in claim 1, wherein the iris hooking portion is formed in an L-shaped cross section composed of a hanging portion hanging from the first ring portion and an extension portion extending radially outward from the hanging portion, and is configured to he hooked on the pupillary margin of the iris in a manner such that the hanging portion is in contact with a side surface of the pupillary margin and the extension portion is in contact with a rear surface of the pupillary margin.
6. The pupil expander as recited in claim 5, wherein the iris hooking portion extends radially outward in such a manner that the extension portion is inclined in either one of circumferential directions.
7. The pupil expander as recited in claim 1, wherein the first ring portion is provided with an instrument hook for hooking a medical instrument for ophthalmic surgery.
8. The pupil expander as recited in claim 1, wherein the first ring portion and/or the second ring portion is provided with an injector part hook for hooking a part of an injector for installing the pupil expander to the pupil or removing the pupil expander from the pupil.
9. The pupil expander as recited in claim 1, wherein the first ring portion is inclined toward an iris side from a boundary connected to the second ring portion as it approaches a portion where the iris hooking portion is provided.
10. The pupil expander as recited in claim 9, wherein the second ring portion is inclined toward the iris side from a boundary connected to the first ring portion as it approaches a central portion.
11. The pupil expander as recited in claim 1, wherein the first ring portion is formed, at its inner peripheral portion or its outer peripheral portion, with a groove extending in a thickness direction.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 shows (a) a plan view and (b) a cross-sectional view taken along the line B-B of a pupil expander according to a first embodiment.
[0034] FIG. 2 is a plan view for explaining the shape of the pupil expander shown in FIG. 1.
[0035] FIG. 3 is a plan view showing a state in which external forces are applied to the pupil expander shown in FIG. 1 from both sides in the left-right direction toward the radially inner side.
[0036] FIG. 4 is a plan view showing a state in which an external force is applied to the pupil expander shown in FIG. 1 from the left direction toward the radially inner side.
[0037] FIG. 5 is a plan view showing a process of installing the pupil expander shown in FIG. 1 in the pupil without using an injector.
[0038] FIG. 6 is a diagram showing a state in which the pupil expander shown in FIG. 1 is inserted in an injector.
[0039] FIG. 7 is a plan view showing a process (first half) of installing the pupil expander shown in FIG. 1 in the pupil using an injector.
[0040] FIG. 8 is a plan view showing a process (second half) of installing the pupil expander shown in FIG. 1 in the pupil using an injector.
[0041] FIG. 9 is a plan view showing a pupil expander according to a modification of the first embodiment.
[0042] FIG. 10 is a plan view showing a pupil expander according to a second embodiment.
[0043] FIG. 11 is a side view of the pupil expander shown in FIG. 10.
EMBODIMENTS FOR CARRYING OUT THE INVENTION
First Embodiment
[0044] Next, a first embodiment of a pupil expander according to the present invention will be described with reference to FIG. 1 to FIG. 8.
Configuration of Pupil Expander
[0045] A pupil expander 1 according to this embodiment is used to expand a pupil P in ophthalmic surgery, such as, e.g., cataract surgery. As shown in FIG. 1, the pupil expander 1 is provided with a ring portion 10 forming a ring and a plurality of iris hooking portions 20 provided to the ring portion 10. Note that in this specification, the term “radial direction” refers to the radial direction of the ring formed by the ring portion 10, and the term “circumferential direction” refers to the circumferential direction of the ring formed by the ring portion 10.
[0046] As shown in FIG. 1, the ring portion 10 is formed of an elastically deformable member having a width “w” of 0.2 mm and a thickness “t” of 0.3 mm. The ring portion 10 is composed of four first ring portions 11 each curved radially inward along the circumferential direction and four second ring portions 12 each curved radially outward along the circumferential direction.
[0047] The first ring portions 11 and the second ring portions 12 are alternately arranged along the circumferential direction on the same plane and are connected to each other at the boundaries K to form a single ring. This ring portion 10 may be made of various materials. The ring portion 10 is preferably made of resin with high-shape-recovery properties or metal with high-shape-recovery properties. Examples of the resin with high-shape-recovery properties include polypropylene, polyester-based thermoplastic elastomer, olefin-based thermoplastic elastomer, urethane resin, acrylic resin, and silicone rubber. Examples of the metal with high-shape-recovery properties include titanium, nickel titanium, and stainless steel.
[0048] As shown in FIG. 2, the first ring portion 11 is formed in such a manner as to curve radially inward between the boundaries K-K on both sides in the circumferential direction so as to depict a gentle substantially circular arc. The linear distance of the first ring portion 11 between the boundaries K-K is about 2.2 mm.
[0049] Further, the first ring portions 11 are arranged such that a pair of first ring portions 11 are arranged in a state of facing each other in the vertical direction in FIG. 1 and the other pair of first ring portions 11 are arranged in a state of facing each other in the horizontal direction of FIG. 1.
[0050] The second ring portions 12 are formed in such a manner as to curve radially outward between the boundaries K-K on both sides in the circumferential direction to depict a gentle substantially circular arc. The linear distance of the second ring portion 12 between the boundaries K-K is about 3.3 mm.
[0051] Further, the second ring portions 12 are composed of a pair of second ring portions 12 arranged in a state of facing to each other in the oblique direction from the right obliquely upper side to the left obliquely lower side in FIG. 1 and another pair of second ring portions 12 arranged in a state of facing to each other in the oblique direction from the left obliquely upper side to the right obliquely lower side in FIG. 1.
[0052] Further, the second ring portion 12 is formed, at its inner peripheral portion, with a groove 12a extending the thickness direction. With this configuration, as will be described later, the second ring portion 12 is easily deformed while increasing the curvature radially outward, which makes it possible to further suppress the movement of the iris hooking portion 20 of the first ring portion 11 (the first ring portion 11 other than the first ring portion 11 to which an external force is applied).
[0053] The relation between the first ring portion 11 and the second ring portion 12 will be described in detail. As shown in FIG. 2, an imaginary circle C passing through the respective boundaries K between the first ring portion 11 and the second ring portion 12 is assumed. In a natural state in which no external force is applied, the first ring portion 11 is formed in a state of being curved radially inward than the imaginary circle C. On the other hand, the second ring portion 12 is formed in a state of being curved radially outward than the imaginary circle C. Note that in this embodiment, as for the linear distance between the boundaries K-K of the first ring portion 11 and the second ring portion 12, the linear distance of the second ring portion 12 is formed to be larger than the linear distance of the first ring portion 11 in a natural state in which no external force is applied.
[0054] As shown in FIG. 1 and FIG. 2, the iris hooking portion 20 is provided between the boundaries K-K on the outer peripheral surface of the first ring portion 11. As shown in (b) of FIG. 1, this iris hooking portion 20 is formed into an L-shaped cross-section composed of a hanging portion 21 hanging from the rear surface of the first ring portion 11 and an extension portion 22 having a substantially semicircular shape in plan view extending radially outward from the hanging portion 21.
[0055] Thus, when the iris hooking portion 20 is hooked on the pupillary margin Ie of the iris I, the hanging portion 21 comes into contact with the side surface of the pupillary margin Ie of the iris I, and the extension portion 22 comes into contact with the rear surface of the pupillary margin Ie of the iris I. Thus, the iris hooking portion 20 of the first ring portion 11 is fitted between the pupillary margin Ie of the iris I and the eyeball. Therefore, the iris hooking portion 20 of the first ring portion 11 can he stably hooked on the pupillary margin Ie of the iris I.
Bask Operation of Pupil Expander 1
[0056] Next, the basic operation of this pupil expander 1 will described with reference to FIG. 3 and FIG. 4.
[0057] FIG. 3 is a plan view showing the state in which an external force is applied to the pupil expander 1 radially inward from both sides in the left-right direction.
[0058] Specifically explaining, when the iris hooking portions 20 of the left and right first ring portions 11 of the pupil expander 1 are moved in the approaching direction, the left and right first ring portions 11 are deformed to be further curved radially inward. At this time, although the iris hooking portions 20 of the upper and lower first ring portions 11 move radially outward, the four second ring portions 12 adjacent to the left and right first ring portions 11 deform radially outward while largely increasing the curvature. Therefore, the movements of the iris hooking portions 20 of the upper and lower first ring portions 11 are suppressed.
[0059] FIG. 4 is a plan view showing the state in which an external force is applied to the pupil expander 1 radially inward from the left direction.
[0060] Specifically explaining, in a state in which the iris hooking portion 20 of the right side first ring portion 11 of the pupil expander 1 is hooked on the pupillary margin Ie of the iris I, the iris hooking portion 20 of the left side first ring portion 11 is moved in the direction to approach the iris hooking portion 20 of the right side first ring portion 11. As a result, the left first ring portion 11 is deformed to be further curved radially inward. At this time, the two second ring portions 12 adjacent to the left side first ring portion 11 are deformed while largely increasing the curvature radially outward, and therefore, the movements of the iris hooking portions 20 of the upper and lower first ring portions 11 are suppressed. Further, the iris hooking portion 20 of the right side first ring portion 11 is caused to be inclined by receiving a repulsive force from the pupillary margin Ie of the iris I, and therefore, the right side first ring portion 11 and the second ring portions 12 positioned on the both sides of the right side first ring portion 11 are caused to be inclined in the direction toward the rear of the right iris I. Therefore, the right side portion of the ring portion 10 receives the repulsive force from the iris I, thereby preventing the movement of the entire ring portion 10 toward the right side.
[0061] When an external force is applied radially inward to one or a plurality of first ring portions 11 as described above, the first ring portion 11 is deformed to be further curved radially inward, and the second ring portions 12 adjacent to both sides of the first ring portion 11 are deformed to increase the curvature. Therefore, the radially inward movements of the iris hooking portions 20 of the other first ring portions 11 are suppressed.
[0062] In particular, in this embodiment, the ring portion 10 is configured such that the radially outward movements of the iris hooking portions 20 of the first ring portions other than the first ring portion 11 to which the external force is applied are suppressed to 70% or less of the radially inward movement of the first ring portion 11 to which an external force is applied.
Installation of Pupil Expander 1
[0063] Next, the method of installing the pupil expander 1 to a pupil will be described with reference to FIG. 5 to FIG. 8. Note that when installing the pupil expander 1 to a pupil, an incision (not shown) for inserting the pupil expander 1 through the cornea or an incision (not shown) for inserting a Sinskey hook 3 as a medical instrument (incision (not shown) for operating the pupil expander 1 is formed in the cornea in advance. For the convenience of explanation, the iris hooking portion 20 located on the right upper side, the iris hooking portion 20 located on the left upper side, the iris hooking portion 20 located on the left lower side, and the iris hooking portion 20 located on the lower right side in FIG. 5, FIG. 7, and FIG. 8 are respectively denoted by reference symbols of 20A, 20B, 20C, and 20D.
[0064] First, a process of installing the pupil expander 1 to a pupil P without using an injector will be described with reference to FIG. 5.
[0065] First, as shown in (a) of FIG. 5, the pupil expander 1 is placed at a predetermined position on the front face of the iris I. Then, using Sinskey hooks 3, the iris hooking portions 20A and 20C of a first pair of first ring portions 11 (the right obliquely upper side first ring portion 11 and the left obliquely lower side first ring portion 11) are moved on the surface of the iris I in the direction of approaching to each other. With this, as shown in (b) of FIG. 5, the first pair of first ring portions 11 are deformed to be further curved radially inward, so that the iris hooking portions 20A and 20C of the first pair of first ring portions 11 are hooked on the pupillary margin Ie of the iris I.
[0066] Next, as shown in (c) of FIG. 5, when the Sinskey hooks 3 are removed from the iris hooking portions 20A and 20C of the first pair of first ring portions 11, the pupil expander 1 returns to its original state by its own elastic force. As a result, the iris hooking portions 20A and 20C of the first pair of first ring portions 11 move in the direction to separate from each other.
[0067] Next, as shown (d) of FIG. 5, the iris hooking portions 20B and 20D of a second pair of first ring portions 11 (the left obliquely upper side first ring portion 11 and the right obliquely lower side first ring portion 11) are moved in the direction to approach to each other with Sinskey hooks 3. With this, as shown in (d) of FIG. 5, the second pair of first ring portions 11 are deformed to be further curved radially inward, and therefore, the iris hooking portions 20B and 20D of the second pair of first ring portions 11 are hooked on the pupillary margin Ie of the iris I. At this time, the iris hooking portions 20A and 20C of the first pair of first ring portions 11 (the right obliquely upper side first ring portion 11 and the left obliquely lower side first ring portion 11) attempt to move radially outward. However, the four second ring portions 12 adjacent to the second pair of first ring portions 11 are deformed while largely increasing the curvature radially outward, which suppresses the movements of the iris hooking portions 20A and 20C of the first pair of first ring portions 11.
[0068] Finally, as shown in (e) of FIG. 5, when the Sinskey hooks 3 are removed from the iris hooking portions 20B and 20D of the second pair of first ring portions 11, the pupil expander 1 returns to its original state by its own elastic force. As a result, the iris hooking portions 20A and 20C of the first pair of first ring portions 11 are slightly moved radially inward, and the iris hooking portions 20B and 20D of the second pair of first ring portions 11 are move radially outward.
[0069] Thus, as shown in (e) of FIG. 5, in a state in which the ring portion 10 is arranged on the front side of the iris I, the iris hooking portions 20A to 20D of the first ring portion 11 are hooked on the pupillary margin Ie of the iris I. With this, it is possible to expanded the pupil P to an appropriate size.
[0070] Next, a process of installing the pupil expander 1 to a pupil P using an injector 2 will be described with reference to FIG. 6 to FIG. 8.
[0071] First, as shown in FIG. 6, the pupil expander 1 is inserted into an injector 2. At this time, for the purpose of easily hooking the iris hooking portions 20 of the pupil expander 1 on the pupillary margin Ie of the iris I when pushing out the pupil expander I from the injector 2, the pupil expander 1 is inserted in the injector 2 in such a manner that the iris hooking portions 20A and 20B of the first ring portions 11 and the iris hooking portions 20C and 20D of the first ring portions 11 are aligned in parallel on the front side and the rear side, respectively.
[0072] Next, as shown in (a) of FIG. 7, the pupil expander 1 is pushed out from the injector 2. Then, as shown in (b) of FIG. 7, the iris hooking portions 20A and 20B of the iris I pupil expander 1 of the first pair of first ring portions 11 (the pair of first ring portions 11 on the upper side in FIG. 7) are caused to be hooked on the pupillary margin Ie of the iris I.
[0073] Next, as shown in FIG. 7 (c), the pupil expander 1 is further pushed out from the injector 2. As a result, the pupil expander 1 returns to its original state by the elastic force of the ring portion 10. Therefore, the iris hooking portions 20A and 20B of the first pair of first ring portions 11 move in the direction to separate from each other.
[0074] Next, as shown in (d) of FIG. 7, by completely pushing out the pupil expander 1 from the injector 2, the iris hooking portion 20C of the second first ring portion 11 (the first ring portion 11 on the left obliquely lower side in FIG. 7) is moved with a Sinskey hook 3 such that the iris hooking portion 20C of the first ring portion 11 first ring portion 11 on the left obliquely lower side in FIG. 7) is moved in the direction to approach the iris hooking portion 20A of the first ring portion 11 facing the surface of the iris I. With this, as shown in (a) of FIG. 8, the second first ring portion 11 is deformed to be further curved radially inward, and therefore, the iris hooking portion 20C of the second first ring portion 11 is hooked on the pupillary margin Ie of the iris I as it is. At this time, the second ring portions 12 (the second ring portions 12 on the left side and the lower side in FIG. 8) adjacent on both sides of the second first ring portion 11 are deformed while increasing the curvature radially outward. Therefore, the movements of the iris hooking portions 20B and 20D of the first ring portion 11 on the left obliquely upper side and the right obliquely lower side are suppressed. Further, the iris hooking portion 20A of the first ring portion 11 on the upper right obliquely side is inclined by receiving the repulsive forces from the pupillary margin Ie of the iris I. As a result, the first ring portion 11 on the right obliquely upper side and the second ring portion 12 on both sides thereof are inclined toward the rear of the iris I on the right obliquely upper side. Accordingly, the right obliquely upper side portion of the ring portion 10 receives the repulsive force from the iris I, and therefore, the movement of the entire ring portion 10 to the right obliquely upper side is suppressed.
[0075] Next, as shown in (b) of FIG. 8, the iris hooking portion 20D of a third first ring portion 11 (the first ring portion 11 on the right obliquely lower side in FIG. 8) is moved with a Sinskey hook 3 in a direction to approach the iris hooking portion 20B of the first ring portion 11 facing the surface of the iris I. As a result, as shown in (c) of FIG. 8, the third first ring portion 11 is deformed to be further curved radially inward, and therefore, the iris hooking portion 20D of the third first ring portion 11 is hooked on the pupillary margin Ie of the iris I. At this time, the second ring portions 12 (the second ring portion 12 on the right side and the second ring portion 12 on the lower side) adjacent on both sides of the third first ring portion 11 are deformed while increasing the curvature. Therefore, the movements of the iris hooking portions 20A and 20C of the first ring portions 11 on the right obliquely upper side and the left obliquely lower side are suppressed. Further, the iris hooking portion 20B of the first ring portion 11 on the left obliquely upper side is inclined by the repulsive force from the pupillary margin Ie of the iris I, and therefore, the first ring portion 10 on the left obliquely upper side and the second ring portions 12 on both sides of the first ring portion 10 are inclined rearward of the iris I on the left obliquely upper side. For this reason, the left obliquely upper side portion of the ring portion 10 receives the repulsive force from the iris I, and therefore, the movement of the entire ring portion 10 toward the left obliquely upper side is suppressed.
[0076] Lastly, as shown in (d) of FIG. 8, the Sinskey hook 3 is removed. With this, the pupil expander 1 returns to its original state by the elastic force of the ring portion 10. Thus, the iris hooking portions 20A to 20C of the first and second first ring portions 11 are moved slightly radially inward, and the third iris hooking portion 20D of the first ring portion 11 is moved radially outward.
[0077] Thus, as shown in (d) of FIG. 8, in a state in which the ring portion 10 is arranged on the front face of the iris I, the iris hooking portions 20A to 20D of the first ring portions 11 are hooked on the pupillary margin Ie of the iris I. With this, it is possible to expand the pupil P to an appropriate size.
[0078] As shown in FIG. 9, the first ring portion 11 may be provided with an instrument hook 23 each for hooking a medical instrument for ophthalmic surgery.
[0079] The first ring portions 11 and/or the second ring portions 12 may be each provided with an injector part hook for hooking a part of an injector for installing or removing the pupil expander 1 to or from the pupil P.
Second Embodiment
[0080] Next, a second embodiment of a pupil expander according to the present invention will be described with reference to FIG. 10 to FIG. 11. In the following description, only the configuration that differs from the embodiment described above will be described, and the description of the same configuration will be omitted, and the same reference symbol will be assigned. In FIG. 10, the state in which the first ring portion 11 is deformed to be moved radially inward is shown with dotted lines.
[0081] As shown in FIG. 10, the first ring portion 11 is formed, at its inner peripheral portion, with a groove 11a extending in the thickness direction. in this embodiment, the groove 11a is formed by being cut into a cutout shape in the thickness direction with a laser on both sides of the iris hooking portion 20 in the first ring portion 11.
[0082] According to this configuration, when the first ring portion 11 is deformed to be curved radially inward, the grooves 11a opens in the circumferential direction like a hinge, so that the iris hooking portion 20 of the first ring portion 11 can be easily moved radially inward. On the other hand, when the first ring portion 11 is deformed to return radially outward, the groove 11a closes like a hinge. As a result, the iris hooking portion 20 of the first ring portion 11 can be returned to a proper position on the radially outward side and can be stopped. In the first ring portion 11, from the viewpoint of ease of manufacturing, a groove 11a extending in the thickness direction may be formed at the outer peripheral portion.
[0083] Further, as shown in FIG. 11, the first ring portion 11 is inclined toward the iris I from the boundaries K connected to the second ring portions 12 as it approaches a part where the iris hooking portion 20 is provided. According to this configuration, the iris hooking portion 20 easily protrudes toward the rear surface of the iris I due to the inclination of the first ring portion 11. Therefore, it is possible to easily and assuredly hook the iris hooking portion 20 on the pupillary margin Ie of the iris I.
[0084] The second ring portion 12 is inclined toward the iris I from the boundaries K connected to the first ring portions 11 as it approaches the central portion. This ensures that the central portion of the second ring portion 12 assuredly conies into contact with the surface of the iris I. Therefore, the pupillary margin Ie of the iris I becomes a state to be sandwiched between the second ring portion 12 arranged on the front surface side of the iris I and the iris hooking portion 20 of the first ring portion 11 arranged on the rear surface side of the iris I, and therefore, the pupil expander 1 can be stably installed.
[0085] As shown in FIG. 10, the iris hooking portion 20 is formed in a parallelogram shape extending radially outward such that the extension portion 22 is inclined to either one of circumferential directions. According to this, when fitting the iris hooking portion 20 between the pupillary margin Ie of the iris I and the eyeball, the edge of the extension portion 22 on the inclination direction side is easily hooked on the pupillary margin Ie of the iris I. Therefore, it becomes possible to easily and assuredly hook the iris hooking portion 20 on the pupillary margin Ie of the iris I. Further, when removing the iris hooking portion 20 from between the pupillary margin Ie of the iris I and the eyeball, the edge of the extension portion 22 on the edge side opposite to the inclination direction is less likely to be hooked by the pupillary margin Ie of the iris I. Therefore, it becomes possible to easily and assuredly remove the iris hooking portion 20 from the pupillary margin Ie of the iris I.
[0086] The embodiments of the present invention have been described above with reference to the attached drawings, but the present invention is not limited to the illustrated embodiments. It should be understood that various modifications and variations can be made to the illustrated embodiments falling within the same as or equivalent to the scope of the present invention.
Description of Symbols
[0087] 1: Pupil expander
[0088] 10: Ring portion [0089] 11: First ring portion [0090] 12: Second ring portion
[0091] 20: Iris hooking portion [0092] 21: Hanging portion [0093] 22: Extension portion
[0094] 2; Injector
