They require that the lens capsule be present to support the IOL. Lenses placed in front of the iris are called anterior chamber IOLs. Because the iris supports them, they do not require the presence of the posterior lens capsule. This is why anterior chamber IOLs were used in the earlier period when cataract surgeons only possessed techniques to remove the entire lens — capsule and all.
Although the posterior chamber is the preferred location of the IOL, modern anterior chamber IOL designs have improved a great deal. These lenses also perform very well and have a long and proven track record. Cataract surgeons may select an anterior chamber IOL at the time of surgery if the posterior capsule support is insufficient. This is not common, but can occur. Other patients may not have received an IOL at the time of their original cataract surgery many years ago.
Even if the natural lens capsule was already removed, an anterior chamber IOL can still be implanted many years later. Whether the IOL is placed in the posterior or anterior chamber i. Thus, modern anterior chamber IOLs still provide a viable and successful second option. The type of material determines whether or not the IOL can fold. All of the lens materials discussed provide excellent optical quality and have gained FDA approval through large, rigorous studies and a proven track record of safety.
The original lens implanted over 50 years ago by Dr. This was the same type of firm plastic used in rigid contact lenses. PMMA lenses were the only lenses available until , and thus have enjoyed a long track record of proven safety.
Because PMMA is rigid, these lenses do not fold, and require a larger incision to be implanted. Some eyes require an unusually strong prescription to focus. In these unusual cases, the appropriate power may not be available in a foldable lens, and a PMMA non-foldable lens is used. Some special situations require an IOL to be sutured into the eye. These lenses are also made of PMMA. Because PMMA lenses are the least expensive to manufacture, they are still the most commonly implanted lenses in many areas of the world.
Although more expensive to manufacture, these are now the most commonly implanted lenses in North America for this reason. The main difference is that the optic can be folded during insertion. Foldable IOLs can be inserted into the eye using one of two techniques. One is to fold the IOL in half using a special forceps.
An alternative is to use a special device that rolls the IOL and injects it slowly into the capsular bag. Once in the eye, foldable lenses open up and return to their original configuration without leaving any crease or mark in the optic. There are many advantages to using the smallest incision possible for cataract surgery. A small incision increases safety both during the operation, and during the early postoperative period.
Because a small incision heals faster, it allows for a more rapid recovery. By not weakening the eye, patients do not have to avoid physical exertion or bending their head over.
The vision will improve faster compared to if a large incision had been used. Because the small incision will stabilize and heal faster, new eyeglasses can be prescribed much sooner.
Finally, the larger the incision, the more it can potentially alter the natural spherical shape of the cornea. Thus, small incisions are much less likely to induce unwanted changes in this desired spherical shape called astigmatism. There are three classes of foldable lens materials — silicone, hydrophobic acrylic, and hydrogel. This material has enjoyed a superb track record of safety and performance. Unlike the liquid silicone that can leak out from breast implants, IOLs are made of solid silicone polymers that are very biocompatible and completely unrelated to the liquid material.
There have been no complications attributable to the material itself. Although the three-piece design is the most popular silicone IOL, there is a variation called the plate haptic design. The acrylic material has been very popular. Their market share is currently much smaller than that of the other two materials. All of these foldable posterior chamber lenses are of excellent optical quality, are safe, FDA approved, and produce outstanding outcomes.
While cataract surgeons may have personal preferences, no clear superiority of one foldable material over another has been demonstrated. The following discussion applies to healthy eyes with no other ocular diseases, problems, or history of surgery. After the age of 50, most patients no longer have perfect natural focus for distance. Eyeglasses will usually improve the focus for far distance objects, such as road signs. Depending upon the activity, this additional improvement may or may not be enough to compel the patient to acquire or wear glasses.
Because of presbyopia — the loss of accomodation [link to presbyopia] — everyone by this age must do something to shift their focus from distance to near. People with contact lenses or otherwise excellent distance vision don reading glasses. People wearing glasses for distance either switch to separate reading glasses or use bifocals. Some nearsighted patients are able to simply remove their distance spectacles and read without eyeglasses.
Although healthy eyes can be focused at any distance with the aid of appropriate eyeglasses, there will be some distance at which the eye will be in natural focus without glasses after cataract surgery. However, no eye over the age of 50, with or without an IOL, can shift the focus between far and near without glasses. For others, a slight amount of myopia nearsightedness may represent a good compromise between being either very blurred for distance or very blurred for near without glasses.
All optical lenses — whether eyeglasses, contact lenses, or IOLs — are manufactured in a large range of different powers. Each IOL model is also manufactured in a large range of powers. Of the 40 to 50 available IOL powers to choose from, there is only one that will be the single perfect lens for far distance focus.
Three or four others will be very close, and the rest will result in significant blur for distance without glasses. Regardless of what the uncorrected vision is after surgery, eyeglasses can always be prescribed to provide excellent distance vision for an otherwise healthy eye. A specific lens power for the IOL is then selected with the goal of achieving this target.
The surgeon uses a computer program to determine the appropriate IOL power in advance of the surgery. The calculations are based upon those dimensions of the eyeball, which determine the unique optical properties of that individual eye.
These painless measurements are taken preoperatively. Since this distance cannot be determined with a ruler, ultrasound medical sonar or similar technology is used to measure this distance in tenths of millimeter accuracy.
Let us assume that the surgeon is seeking to optimize distance focus without glasses postoperatively. The IOL power selected is an estimate derived from these calculations. However, without the benefit of trial and error as is employed in prescribing glasses or contacts , perfect distance focus is not assured. Eyeglasses can then be worn as an option to fine-tune and achieve best distance focus. Although there is a wide range of targeted results, a very common outcome following IOL surgery is that the patient can see reasonably well indoors and around the house without glasses.
They will utilize reading glasses to read comfortably. They will pick and choose when to don distance glasses to enhance their far focus. This might be for driving, for example. Many patients will continue to choose bifocals out of habit or for convenience. In essence, the patient will have the same focusing options that all other patients over the age of 50 have.
The investment for me in the surgery is priceless. I received excellent service and aftercare, too. Lens replacement is one of the safest medical procedures you can have, and there are millions of these operations performed throughout the world every year.
Like all surgical procedures, there are some possible complications to be aware of, but these are rare and usually resolved easily with additional treatment. The risk of complications is also lowered if you choose a reputable treatment provider with the very best staff and facilities, like Optegra.
Lens replacement is a great alternative treatment, and unlike laser eye surgery it has the added bonus of preventing you from ever needing surgery for cataracts.
After your treatment, it is normal to experience some itching and mild discomfort for the first day or two, but this will soon pass. Most people return to work around 3 days after having lens replacement surgery, although this will depend on the nature of the work you do.
Your vision will gradually improve over the first couple of weeks following treatment, with optimum vision usually being reached after around weeks. In the meantime, take a look at our lens replacement surgery report , which explains some of the most common queries about the treatment. For a personalised assessment of whether lens replacement surgery is right for you, head to one of our nationwide eye hospitals for a detailed one-to-one consultation with one of our world-class eye surgeons. All consultations are free and there is no obligation to book further treatment.
So, how long do cataract lenses last? Unlike the natural lenses of the eye, IOLs do not break down and never need to be replaced. To reap these long-lasting benefits, patients should follow any aftercare instructions as given by their doctor following surgery. Complete recovery can be expected over 1 — 2 days, but this depends on your original eyesight and any underlying health conditions. OAV can schedule follow-up appointments to make sure healing is going as planned. Follow these recovery instructions following laser cataract surgery in Los Angeles:.
If you experience severe pain or severe loss of vision, contact our office right away to learn about your next steps. Since our inception, Ophthalmology Associates of the Valley has aspired to be the leading resource for comprehensive eye care in Los Angeles, CA. As eye care technology evolves, we will continue to provide the latest in cataract surgical techniques and solutions.
Contact our clinic to learn about your intraocular lens implant options and get rid of cataracts. Regardless of your needs, you can rest assured your vision is in good hands. Images may contain models.
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