In a healthy human eye, the cornea should have a perfectly round shape – like a basketball. But when you have astigmatism, the cornea attains an oval shape – somewhat like an American football. So, people with astigmatism tend to suffer from blurred vision at distance and near because images do not focus sharply on the retina.
What about Toric IOLs?
Toric IOLs are similar to their soft contact lens counterparts in that they have different levels of powers in various meridians of the lens to rectify the asymmetric power of the eye.
A cataract surgery with a Toric IOL placement is similar to any other cataract surgery with a conventional IOL. But before the procedure, the surgeon needs to choose the most suitable Toric IOL power, as well as the necessary orientation of the implant in the eye to successfully correct the astigmatism. Meticulous preoperative planning is critical. Thus, each patient undergoes extensive preoperative testing with the most advanced equipment in the world including devices such as the Lenstar optical biometry, pentacam, topography, and autokeratometry.
Toric IOLs typically feature special markers on the peripheral to help surgeons identify the orientation of the astigmatism correction in that specific lens.
After implantation, the surgeon rotates the Toric IOL to align the astigmatism correction for best results. Although the use of a Toric IOL during the surgery does not necessarily increase the likelihood of complications, a misaligned IOL can result in blurred vision that then needs to be corrected with glasses, contact lenses, LASIK, or rotation of the toric IOL. So it needs to be done perfectly the first time. This is also why Dr. Elkins utilizes ORA (Optiwave Refractive Analysis) during surgery. The ORA takes a quick and precise measurement to confirm the IOL power before implantation. Once the toric IOL is implanted, the ORA assists Dr. Elkins to make sure that is aligned correctly on the correct axis. Sometimes multiple measurements are required to confirm that the astigmatism is treated as best as possible.
How Toric IOLs Work to Correct Astigmatism
Toric IOLs have different powers in different meridians of the lens to correct the asymmetric power of the eye that is characteristic of astigmatism.
Alcon's AcrySof IQ Toric IOL has three dots on each side of the lens to enable the cataract surgeon to align the IOL in the eye for precise astigmatism correction.
Cataract surgery with a toric lens implant (IOL) is essentially the same as cataract surgery with a conventional IOL, but with a couple of important differences.
Prior to surgery, measurements are taken to enable cataract surgeons to choose the most beneficial toric IOL power and the required orientation of the implant in the eye to correct the astigmatism successfully.
Toric IOLs have special markers on the peripheral parts of the lens that enable the surgeon to see the orientation of the astigmatism correction in the lens. Once the toric IOL is implanted in the eye, Dr. Elkins then rotates the lens so the astigmatism correction is properly aligned for best results.
Use of a toric IOL during cataract surgery does not increase the risk of common cataract surgery complications, but a misaligned toric IOL can cause blurred vision that cannot easily be corrected with eyeglasses or contact lenses.
Brands: Tecnis Toric Aspheric IOL (Abbott Medical Optics).Read Norm M.'s review of Brad Elkins, MD on Yelp
Excellent Toric IOL Outcomes
Research has shown that toric lenses produce excellent visual results after cataract surgery and can correct astigmatism more effectively than limbal relaxing incisions.
One study found that 94 percent of astigmatic eyes treated with toric lens implants had 0.50 D or less astigmatism and 98 percent had 0.75 D or less residual astigmatism after surgery, enabling people to see acceptably well without glasses or contact lenses.
And studies evaluating patient satisfaction after cataract surgery have found the majority of patients receiving toric IOLs are highly satisfied with their vision after surgery.
One study found 92 percent of patients report no difficulty with driving at night without eyeglasses six months after surgery, and 97 percent of patients receiving toric lens implants would choose the same IOL to be implanted again.