JPS63230161A - Intraocular lens - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to medicine, and more particularly to ophthalmology and intraocular lenses.

[Conventional technology]

One of the most important problems in ophthalmological practice these days is how to correct vision after cataract extraction.

There are many methods for such correction, such as glasses or contact lenses. However, vision correction with the aid of glasses cannot restore the patient's normal vision, and correction with the aid of contact lenses is not tolerated by all patient pressures, especially cataracts are very common. (80 to 85 inches) It is intolerable for old people. This is the reason why ophthalmologists all over the world are searching for other ways to solve the above problems. Another solution to the above problem is intraocular correction, ie the implantation of an artificial lens.

Various structures of intraocular lenses are known, but most of these are implanted into the anterior chamber of the eye and attached to the iris or lens capsule.
and the lens support element is secured by sutures. Such intraocular lenses are clearly
It is far from meeting all the requirements essential for adequate vision correction.

The greatest success has been intraocular lenses, which are designed to be implanted intracapsularly. An eye with an intraocular lens implanted within the capsule is no different from a normal aphakic eye. The lens capsule isolates the intraocular lens from the surrounding tissues and thus systematically prevents its displacement, while the close mutual positioning of the intraocular lens center and the natural lens center prevents unilateral or bilateral Helps in obtaining binocular vision in cases of phakosis.

However, in order to achieve successful intracapsular implantation and thus more adequate vision correction, an intraocular lens was created based on a novel principle of intraocular lens fixation within the human eye. There must be.

In this technique, 1. has a fixing element and a support element. Intraocular lenses are known (Soviet inventor badge; 63,174
No., IPCA61F9100). Both of these elements are substantially identical and made of a rigid material and in the form of a loop-shaped protrusion fixed to the side of the lens, except that the fixation element serves as a suture material for guidance and retention. The only difference is that it has two protrusions. This lens is implanted into the lens capsule.

However, implantation of this intraocular lens involves a long surgical wound commensurate with the overall dimensions of the lens, including the supporting elements. Moreover, the need to stitch the eyelet for the threading of the fixation element into the lip of the iris incision complicates the implantation technique of the intraocular lens.

Furthermore, an optical lens is provided with a telescopic support element and a fixation element fixed on diametrically opposite sides of the optical lens, said fixation element being essentially a loop-shaped protrusion displaceable in a radial direction from an elastic material. Intraocular lenses are known (for example, US Pat. No. 4,316,292, IP
CA61F1/16. Published February 23, 1982).

Implantation of an intraocular lens into a patient's lens capsule is performed as follows. After extracapsular cataract extraction, a specially calibrated spatula is inserted into the empty lens capsule and the distance from the equator to the center of the lens capsule is measured.

The support element of the intraocular lens, made as a loop-shaped protrusion, is then bent outward or inward so as to obtain a distance to the center of the lens equal to the distance from the lens capsule to the center of the pupil.

After matching the required index of the intraocular lens, the intraocular lens is introduced into the lens capsule and the fixation element is sewn into the basal iridotomy.

However, such implantation of the above-mentioned intraocular lenses requires large operative surgical wounds, extra instruments in the form of graduated spatulas, and a very high degree of precision in lens alignment relative to the optical axis of the eye. Most importantly, such implantation requires fixation of the fixation element in the eye by sewing, which is a very complex task from a technical point of view.

Another intraocular lens is known that includes an optical lens and a radially disposed support element made of a rod with a rounded end (e.g., U.S. Pat. No. 4,159 .546, IPCA61F 1/16
, A61F' 1/24. Published July 3, 1979).

The above-mentioned intraocular lens passes through the dilated pupil and the surgical wound created in the anterior part of the lens capsule, with the compression of the supporting element during implantation and its leaning against the body of the eyelash, followed by the posterior eye. It is implanted into the posterior chamber of the eye by fitting the entire lens into its correct position within the chamber.

Due to the construction of such intraocular lenses, the surgeon has a high degree of sophistication in selecting the forces to be applied during implantation to introduce the lens itself into the posterior chamber of the eye and to compress the supporting elements. Therefore, ophthalmological surgeons are required to be highly skilled in performing this transplant.

Even the slightest mistake made during the implantation process could result in damage to the patient's ocular components.

Another disadvantage of the structure of the intraocular lens described above is that the abutment of the posterior chamber onto the equator is carried out at essentially one point on each of the support elements, which necessarily causes vibrations of the lens. This results in a blurred image of the visual object during this movement on the retina of the eye.

[Problem that the invention seeks to solve]

The main and essential object of the invention is therefore to provide an intraocular lens which, with suitably provided support elements, makes it possible to significantly reduce the degree of trauma of the implantation operation and to simplify this operation. That's true.

[Means for solving problems]

Said object comprises an optical lens and a plurality of support elements rigidly fixed to said optical lens and disposed radially thereon, said support elements being formed as rods and bent outwardly so that said support elements are rigidly fixed to said optical lens and arranged radially thereon. This is achieved by an intraocular lens having an end portion, the support element of which is made of a material that possesses plastic memory properties (transformed plasticity) in both heated and cooled states.

This feature greatly reduces the degree of trauma to the grafting process and also simplifies the grafting process.

The supporting elements of the intraocular lens, which are formed as rods, are arranged in a plane perpendicular to the main optical axis of the lens, and the outwardly bent end portions of each rod are arranged in a circle that coincides with the equator of the lens capsule. It is convenient to be placed in

It is possible that the outwardly bent end of the support element of the intraocular lens is held tightly to the side of the lens.

This prevents the intraocular lens from vibrating within the lens capsule.

〔Example〕

The invention will be explained below by means of preferred embodiments thereof in the accompanying drawings, in which: FIG.

The intraocular lens disclosed in the present invention can be any conventionally known optical lens 1 (FIG. 1.2) of any structure, such as the optical lens 1 (FIG. 1.2).
6 a plano-convex lens as shown in FIG. 6 and support elements 2 and 3 equidistantly spaced along the periphery of this lens 10 and held on the peripheral sides 4 of the lens 1 by any known technique. It is equipped with. This support element 2.3 is
It is made of an alloy that has thermomechanically induced plasticity (plastic memory) in the heated and cooled states within the shape recovery temperature in the heated and cooled states between approximately 35°C and 20°C.

Figure 1.2.3 shows an intraocular lens with support elements 2, 3 placed on the peripheral side of the lens 10 and prepared for implantation at 20°C (while in the cooling state).

Figure 4.5.6 shows the temperature (35
The intraocular lens with the support element 2°3 is shown in the expanded state at ~36°C). These support elements are made in such a way that the outwardly bent end 5 (FIG. 4.5) of each rod (2, 3) lies inside a circle that coincides with the equator of the lens capsule.

The outwardly bent end of the rod of the support element 2.3 lies in a plane 7 perpendicular to the main optical axis 8 of the lens (
3.4, 5.6). The outwardly bent ends of the rods of the support element 2 are free (FIGS. 1 and 4). The free (unfixed) end of the support element 3, made as an outwardly bent end, is rigidly fixed on the side surface of the lens 1 (FIG. 2.5).

According to the invention, the implantation of an intraocular lens is performed as follows (Figures 7.8 and 9.10).

When extracapsular (capsular) cataract extraction is performed, the internal space 11 of the anterior chamber 10 and lens capsule 12 is at a temperature of about 15°C or 20°C.
filled with cooled saline.

In preparation for implantation, the intraocular lens is prepared in a physiological state with a temperature below +20"C (this corresponds to the temperature before martensitic transformation), in which the support element 2 or 3 assumes a preset compressed shape in the cooled state. It is cooled in saline (Fig. 1.2).By accessing through the surgical wound made in the cornea 13 and through the opening 14 in the anterior part of the lens capsule, a surgical needle, forceps, etc. By using any suitable retainer (not shown) such as the Internal space 11 (7th
) and the lens is positioned such that the optical axis 8 of the lens 1 is disposed at right angles to the equatorial plane 7 of the lens capsule 12.

Next, a glass of saline warmed to 35°C was added to the anterior chamber of the eye.
is added to the internal space 11 of the lens capsule 12. While doing so, the intraocular lens is retained within the lens capsule 12 as described above (FIG. 8). Support element 2 or 3
The material from which is made is at a temperature at which shape recovery occurs in the heated state (point of reverse martensitic transformation), which is equal to the temperature of the human body, so that the supporting element 2 or 3 recovers its previous shape and this elongates. while touching the equator 6 of the crystalline lens technique @12, thus fixing and centering the optical axis 8 of the lens t1 within the optical axis 15 of the eyeball (9th
figure). Such an arrangement of the support element 2 or 3 of the intraocular lens within the lens capsule 12 (FIGS. 9 and 10) results in a curved portion 5 of the support element 2 or 3 on the equatorial periphery 6 of the lens capsule 12. By arranging and abutting the lenses, the lens can be reliably fixed inside the crystalline lens capsule 12 along the inner peripheral edge 6 of the equator.

The intraocular lens maintains its correct position within the eye (as shown in Figure 4.5.6) due to the patient's body temperature.

Whenever it becomes necessary to remove the intraocular lens, the anterior chamber 10 and the interior space 11 of the lens capsule 12 are removed by the glass 2.
Cooled to a temperature below 0°C.

As a result, the support element 2 or 3 assumes a preset shape in the cooled state and collapses along the peripheral side surface 4 of the lens 1 (
1.2.3), so that the intraocular lens can be easily removed.

The application of alloys possessing thermomechanically induced plasticity in the heated and cooled states increases the ability of the material of the support elements 2, 3 to recover a preset shape when heated up to the temperature of the patient's body. It reduces the complexity and time consumption of the surgical work and obviates the need to attach the lens with sutures, thereby highlighting the substantial differences between the intraocular lenses of the present invention and previously known intraocular lenses. It is something.

In addition to this, in order to ensure that the material from which these supporting elements are made exhibits "hyperelastic" characteristics within the temperature range of reverse martensitic transformation (i.e. shape recovery under heated conditions), the capsule of the natural lens 12 is excised. three supporting elements 2 along the equator of
By arranging the lenses 3 at equal distances, the lens 1 is firmly fixed and vibrations of the lens 1 are reduced.

Apart from this, the application of the intraocular lens disclosed in the present invention preserves the functions of the pupil and iris of the human eye, and prevents residual diseases during and after surgery, namely wound damage to the endothelial cells of the cornea and iris. to prevent dislocation of the lens into the vitreous body of the anterior chamber of the eye.

〔Effect of the invention〕

The intraocular lens of the invention has a low weight since the alloy from which the support element is made is characterized by a low density.

The structure of this intraocular lens is simple and reliable in implantation, which is achieved by the nature of the phase (lenticular) structural transformation that underlies the effect of thermomechanical plasticity memory.

The alloys used as support elements 2, 3 are chemically and biologically inert, have high strength and are non-magnetic. In addition, the disclosed intraocular lenses can be easily removed from the eye.

[Brief explanation of the drawing]

1 is a schematic front view of an intraocular lens according to the invention prepared for implantation; FIG. 2 is a schematic front view of an intraocular lens according to the invention prepared for implantation; FIG. FIG. 3 is a schematic side view of an intraocular lens prepared for implantation according to the invention; FIG. 5 is a schematic front view of the intraocular lens of the present invention after implantation of the intraocular lens of FIG. 2; FIG. 6 is a schematic front view of the intraocular lens of the present invention as shown in FIG. 7 to 9 are diagrams illustrating each successive stage of the implantation process of an intraocular lens according to the present invention; and FIG. 10 is a schematic side view of the implanted intraocular lens according to the present invention. [Schematic view of a human eye] showing the position of the 1... lens, 2, 3... support element, 4... side of the lens, 5... bent outward. f″Lfc end portion, 6
... Peripheral part of lens capsule equator, 7... Plane, 8...
- Main optical axis, 10... Anterior chamber of the eye, 11... Internal space of the lens capsule, 12... Crystalline lens capsule. Below margin f/Ii4

Claims (3)

[Claims] 1. In an intraocular lens comprising an optical lens and a radially arranged support element rigidly fixed to the optical lens and made as a rod with an outwardly bent end, said support element (2, 3) An intraocular lens characterized in that it is made of a material that possesses the effect of plastic memory in heated and cooled states. 2. The rods (2, 3) are arranged in a plane (7) perpendicular to the main optical axis (8) of the lens (1), and the outwardly bent end portion of each rod is located in the lens capsule (12). Intraocular lens according to claim 1, characterized in that it is located on a circle (6) that coincides with the equator (6) of the intraocular lens. 3. 3. Intraocular lens according to claim 2, characterized in that the outwardly bent end of each rod is attached to the side of the lens (1).