With conventional IOLs, typically you must wear eyeglasses or contact lenses in order to use a computer, read or perform other close-up tasks within arm's length.Īccommodating IOLs are premium intraocular lenses that expand the range of clear vision with both an aspheric design and flexible "haptics" - the supporting legs that hold the IOL in place inside the eye. Accommodating IOLsĬonventional spherical IOLs are monofocal lenses, meaning they are designed to provide clear vision at a single focal point (usually far away for good driving vision, for example). LASIK and PRK can also be performed after cataract surgery to correct residual astigmatism, but toric IOLs decrease the likelihood of needing these additional surgical procedures. But typically in such cases, the amount of astigmatism remaining after implantation of a toric IOL is far less, making a better LRI outcome more likely. In some cases - even when a toric IOL is used - limbal relaxing incisions may be needed after cataract surgery to fully correct astigmatism. When these incisions heal, the cornea becomes more spherical in shape, reducing or eliminating astigmatism. In LRI, small incisions are made at opposite ends of the cornea, very near the junction between the cornea and the surrounding white sclera. Prior to the development of toric IOLs, cataract surgeons had to perform a procedure call limbal relaxing incisions (LRI) to correct astigmatism during or after cataract surgery. Then, when the toric IOL is implanted during the cataract procedure, the surgeon rotates the IOL so the markings on the IOL are aligned with the markings on the cornea to ensure proper astigmatism correction. Just prior to cataract surgery, the surgeon places temporary markings on the patient's cornea that identify the location of the most curved meridian of the front of the eye. They also have alignment markings on the peripheral part of the lens that enable the surgeon to adjust the orientation of the IOL inside the eye for optimal astigmatism correction. Like toric soft contact lenses, toric IOLs can correct astigmatism because they have different powers in different meridians of the lens. Toric IOLs are premium intraocular lenses that correct astigmatism as well as near sightedness or long sightedness. Premium aspheric IOLs, on the other hand, match more closely the shape and optical quality of the eye's natural lens, and thereby can provide sharper vision - especially in low light conditions and for people with large pupils. In other words, the eye's natural lens is aspheric ("not spherical").Ī spherical intraocular lens can induce minor optical imperfections called higher-order aberrations (HOAs), which can affect quality of vision, particularly in low-light conditions such as driving at night. Though a spherical IOL is relatively easy to manufacture, this design does not mimic the shape of the natural lens inside the eye, which varies in curvature from center to periphery. Traditional intraocular lenses have a spherical optical design, meaning the front surface is uniformly curved from the centre of the lens to its periphery. If you go private, you should be able to choose from a wider selection of IOLs and during your preoperative exam and consultation, your cataract surgeon can help you choose the best IOL for your needs, as well as additional cataract surgery costs involved if you choose one of the following premium lens implants. This means the lens will be fixed for either near or distance vision, but not both. With the NHS, you will usually be offered monofocal lenses, which have a single point of focus. The following is an overview of premium IOLs currently available. The best intraocular lens for you depends on many factors, including your lifestyle and your specific visual needs. Today there is a wide variety of premium IOLs to choose from. IOLs are also used for a type of vision correction surgery called refractive lens exchange.īefore the use of intraocular lenses, if you had cataracts removed, you had to wear very thick glasses or special contact lenses in order to see clearly after cataract surgery, since no device was implanted in the eye to replace the focusing power of the natural lens. Intraocular lenses (IOLs) are medical devices that are implanted inside the eye to replace the eye's natural lens when it is removed during cataract surgery.
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