JPH08126653A - Intraocular lens which has haptic part with asymmetrical cross section - Google Patents

Abstract

PURPOSE: To enable haptic portions to be easily seen when an intraocular lens is inserted and placed so as to simplify the implantation of the intraocular lens, by forming the haptic portions extending outwardly from the optic lens with a plane, and providing asymmetrical sections with respect to the plane for at least a part of the haptic portions. CONSTITUTION: An optical lens and haptic portions extending outwardly from the body of the optical lens are formed with a plane respectively. The body of the optical lens has an angle of about 10 degrees with respect to the plane. At least a part of each haptic portion has an asymmetrical section with respect to the plane of the haptic portion. The lens comprises a body of the optical lens and haptic portions 5. Each haptic portion includes a connecting portion 6 which is connected to a mid-section 7 and a distal end portion 8 of the optical lens body. Since this lens can easily be seen during implantation, it is safer and easier to insert it through a tunnel valve as compared with the conventional intraocular lenses.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to the field of ophthalmology, and more particularly to new IOLs that have been found to significantly facilitate implantation of intraocular lenses (IOLs) and improve their results.

[0002]

The most common age-related observation is that when the lens of the eye becomes cloudy, the sharpness of the eyesight decreases, which results in a blurred image.
This opacification of the lens is called cataract and is caused by molecular rearrangement of lens components with light scattering. Some cataracts also develop a yellowish brown color due to pigment deposition, which is also accompanied by reduced vision. Cataracts most often occur in the elderly. However, it can also be so affected because of diabetes or many types of injury.

The only cataract procedure that can be used is to remove the frosted lens by surgery.
Once the lens is removed, a new artificial lens is needed so that the eye can be clearly focused. There are three methods of visual recovery after cataract surgery. By cataract glasses, by contact lenses, or by implantation of intraocular lenses.

Intraocular lens implants are made from biocompatible materials such as polymethylmethacrylate (PMMA) or silicone and are placed inside the eye by surgery directly related to cataract removal. Cataract surgery mainly involves the introduction of surgical microscopes, viscoelastic substances such as H
It has changed dramatically over the last two decades as a result of the introduction of ealon ^(R) , improved equipment, improved surgical techniques, and ingenuity of the intraocular lens implant itself. Current methods are constantly evolving and improving.

To date, most intraocular lens implants involve first making an incision 1 in the cornea, as shown in FIG. 1, and then filling the anterior segment of the eye with a viscoelastic material. The IOL is then inserted through the incision (FIG. 2), treated past the iris (FIG. 3) and then placed close to the posterior wall of the lens capsule (FIG. 4). The IOLs shown in FIGS. 2-4 have two haptic portions attached to the lens at an angle α (referred to as the angulation), which is shown in FIG. This angle is often about 10 degrees.

A popular surgical procedure is the phacoemulsification technique, which utilizes ultrasound to shatter the lens nucleus and thus remove lens material through an incision approximately 3 mm long. Is possible. The advantages of a small incision are faster visual rehabilitation, faster healing and lesser astigmatism than a conventional large incision. A hollow titanium needle having a diameter of about 1 mm is activated and vibrated by a magnetostrictive ultrasonic device. This mechanical vibration transforms the lens into an emulsion. Therefore, it is named as lens emulsification.

With the sophistication of lens emulsification techniques, incision techniques have evolved to allow wound sealing without the need for suturing. In this technology, this incision technique is called "self-sealing incision".

The self-sealing incision described above is based on a valve constituted by the inner lip of the corneal tissue that is pressed by the internal pressure of the eye against the outer portion of the wound (FIG. 6). This valve is made entirely within the cornea (denoted by reference numeral 3, "clear corneal incision") or partially within the sclera (denoted by reference numeral 2, "scleral tunnel incision"). . The surgery must be very accurate. In the case of the corneal scleral tunnel, the scleral incision is made 1-2.5 mm outside the limbus, which is the gray line separating the clear cornea from the white cornea. Using a knife with a rounded tip, a tunnel / valve is made with a scleral half depth and a width of about 3 mm and a length of 2 mm. Then, an incision is made into the anterior chamber. Extend a further 1-2 mm tunnel / valve into the transparent cornea with exactly the same careful and precise movement using a sharp-tipped knife.
Following this operation, a highly accurate valve construction is prepared. After removing the opaque lens, the incision is extended to the size required to implant the intraocular lens, the anterior segment of the eye is filled with viscoelastic material, and the lens is implanted. Therefore, it is very important to minimize lens size and lens handling during implantation to allow the use of extremely small incisions (often referred to as tunnel incisions). Tunnels or small incision techniques are for example Menapace
By J Cataract Refract Surg 16 (5), 1990, 567
~ 77 and Ormerod et al. Ophthalmology (US), 100
(2), 1993, pp. 159-63.

The conventional incision 1 shown in FIG. 1 is closer to the edge and straight into the anterior chamber, but does not have the advantages discussed above. For the reasons given above, the tunnel incision offers great advantages, but it is crucial that a suitable lens is available for this procedure. In this regard, considerable effort has been expended to develop a foldable lens that can be deformed during the insertion phase, but returns to its expected size after insertion into the eye. This concept is based on U.S. Pat.
244 and 4,573,998.

[0010]

Once the lens is inserted, it must be handled carefully to avoid damaging the eye area and to ensure proper placement.
For example, there is a risk that the leading haptic portion or loop during insertion will contact the inside of the cornea (Figure 7). The cornea
It contains a layer of endothelial cells that are extremely sensitive to mechanical damage. The function of the endothelial cell layer is to pump aqueous components into the cornea and to pump excess fluid so that transparency is maintained. The pump is placed on the cell membrane of the endothelium.
The cells are hexagonal in shape and, together, appear to fit very well with the tiles on the floor. The hexagonal shape minimizes mechanical stress between the units. Mechanical damage to the endothelial cells may interfere with the above-mentioned mechanism and may further cause cell death, and if significant cell death occurs, the cornea becomes edematous and opaque, and corneal transplantation occurs. Is required. That is, it is useful because the surgeon can see the haptic portion during insertion of the lens.

In addition, it is essential that the surgeon be able to see the haptic portion as he manipulates the lens through the iris to ensure that the lens is properly positioned in the bag. For these reasons, some lenses have a colored haptic portion that allows the haptic portion to be better viewed with the naked eye during lens insertion and placement. The colored haptic portion is easier to achieve when making a three piece lens, but much more difficult when the lens is obtained as one piece from a lens blank. Therefore, there is a need in the art for an intraocular lens that includes a haptic portion that is easily seen during insertion and convenient to produce.

[0012]

As a result, the present inventors have found that
The haptic portion is more easily observed during insertion and placement of the lens, allowing the lens to be easily manufactured and pioneering a new concept for intraocular lenses that overcomes the disadvantages of the prior art.

In particular, the inventor has found that a one-piece lens having a haptic portion with a substantially rectangular or square cross-section during surgery due to its optical properties, ie its reflective and refractive properties. I am aware that it is difficult to see. The inventor has discovered that a haptic portion having an asymmetric cross-section with respect to the plane of the haptic portion facilitates viewing and tracking of the haptic portion during insertion and placement in the capsule. This property thus makes transplantation much more convenient and safe. Accordingly, the intraocular lens of the present invention includes an optical lens body and a haptic portion extending outwardly from the optical lens. The haptic portion is formed by a plane, and at least a portion of each of the haptic portions has a cross section that is asymmetric with respect to the plane of the haptic portion. The haptic portion exhibits reflective and refractive properties thereby facilitating easy viewing of the haptic portion during insertion and placement, thereby facilitating intraocular implantation of the intraocular lens.

These and other advantages provided by the intraocular lens of the present invention will become more fully apparent in the detailed description which follows.

The intraocular lens of the present invention comprises an optical lens body and a haptic portion extending outward from the optical lens body. Each of the haptic parts is formed by a plane. The optical lens body is also formed by a plane that may or may not be coplanar with the plane that forms the haptic portion. In a preferred embodiment, each haptic portion is angled with respect to the plane of the optical lens body by about 10 degrees, for example, as shown in FIG.

An important feature of the present invention is that at least a portion of each haptic portion has a cross section that is asymmetric with respect to the plane of the haptic portion. A lens according to the invention is shown in FIG. The lens 10 includes an optical lens body 4 and a haptic portion 5. Each haptic part comprises a connecting part 6, which connects with the optical lens body, the intermediate part 7 and the end part 8.

As illustrated in FIGS. 15-19, at least a portion of each haptic portion has an asymmetric cross-section with respect to the plane P-P forming the haptic portion. For example, in FIG. 15, the haptic part of the asymmetrical cross section has an isosceles triangular cross section, whereas in FIG. 16, the haptic part of the asymmetrical cross section has an equilateral triangular part. In FIG. 17, the haptic portion of the asymmetric cross section has an L-shaped cross section, and in FIG. 18, the haptic portion of the asymmetric cross section has a quadrant cross section. In each of these embodiments, all or only some of the haptic portions have the asymmetric cross section described above. If only a portion of the haptic portion has the asymmetric cross section described above, this portion may be the connecting portion 6, the middle portion 7 or the end portion 8 or a combination thereof. As a result, the haptic portion exhibits optical properties, i.e., reflective and refractive properties, which make it easily visible during lens implantation. Any part of the haptic part that is not asymmetrical, ie symmetrical, may be rectangular, for example (FIG. 19).

The lens according to the invention makes safer and easier insertion through the tunnel / valve compared to conventional IOLs.
In particular, an intraocular lens with a haptic portion having an asymmetrical cross-section as described above is much easier to see during implantation. As discussed above, it is essential that the haptic portion be visible through the iris when the surgeon handles the lens to ensure that the lens is properly placed in the bag. The lens according to the present invention may be made from any conventional lens material and is easily manufactured in one piece from a lens blank. Other manufacturing methods known in the art can also be used.

The particular embodiments described above are provided by way of illustration of the invention and are not meant as a limitation of the scope of the invention.

[Brief description of drawings]

FIG. 1 shows a method of making an incision in the cornea.

FIG. 2 shows insertion of a conventional IOL through an incision.

FIG. 3 illustrates handling a conventional IOL past the iris.

FIG. 4 shows a conventional IOL placed in a lens capsule.

FIG. 5 shows a conventional IOL with the haptic portion angled with respect to the optical portion.

FIG. 6 shows a self-sealing incision.

FIG. 7 shows conventional IOL insertion through an incision.

FIG. 8 shows insertion of an IOL of the present invention.

FIG. 9 shows insertion of an IOL of the present invention.

FIG. 10 shows insertion of an IOL of the present invention.

FIG. 11 is a diagram showing the direction of the force applied to the IOL.

FIG. 12 is a diagram showing an example of an IOL insertion method.

FIG. 13 is a view showing an angle attached to an IOL.

FIG. 14 is a diagram showing an IOL of the present invention.

FIG. 15 is a sectional view of a haptic portion according to the first embodiment.

FIG. 16 is a sectional view of a haptic portion according to the first embodiment.

FIG. 17 is a sectional view of a haptic portion according to the third embodiment.

FIG. 18 is a sectional view of a haptic portion according to the fourth embodiment.

FIG. 19 is a sectional view of a haptic portion according to the fifth embodiment.

FIG. 20 is a sectional view of the IOL.

Claims (5)

[Claims] 1. An improved optical lens body and a haptic portion extending outwardly from the optical lens body, wherein at least a portion of each haptic portion has a cross section that is asymmetric with respect to the plane of the haptic portion. , An intraocular lens in which each haptic part is formed by a flat surface. 2. The section having a triangular cross section.
The intraocular lens described. 3. The intraocular lens of claim 1, wherein the portion has an L-shaped cross section. 4. The intraocular lens of claim 1, wherein the portion has a quadrant cross section. 5. The intraocular lens of claim 1, wherein the haptic portion is angled with respect to a plane defined by the optical lens body.