New Lens Implants Can Correct Astigmatism after Cataract Surgery

Cataracts are a clouding of the natural lens in the eye. The lens becomes yellow or opaque preventing light and images from reaching the retina. They most frequently affect older patients, but may appear in younger individuals as well. While the most common type of cataract is age related trauma, oxidative stress caused by drugs, poor diet, environment, and disease or congenital issues may precipitate lens opacities in younger folks. Over the years, surgery to correct this common vision problem has evolved in several dramatic ways.

Early surgical cataract procedures involved the affected lens being removed, and the patient had to wear very thick eye glasses in order to see. This posed several optical problems which were then best corrected with contact lenses. As time passed, the first intraocular lens implant was developed. This early lens was placed in front of the iris, (colored part of the eye), and replaced the natural lens in power to refract light on to the retina. It soon became apparent that vibrations in this implant damaged the inner most layer of the cornea called the endothelium. On occasion this in turn resulted in an opaque cornea and the need for a corneal transplant.

This problem was solved by the next generation of lens implants that were placed behind the iris, and were called posterior chamber implants. They were secured far enough away from the cornea, so that they had no impact on it. These early lens implants were fairly large, and required a large incision to remove the natural lens and implant the new one. As time progressed, Phacoimulsification became the procedure of choice for cataract surgeons. This revolutionized the procedure. A small incision was required, and as a result fewer sutures were needed. Along that time, foldable implants came along that could be inserted into the eye through that small opening.

The next big advancement was removing the cataract, and inserting the implant directly through the cornea. This approach did not require any sutures, and thus healing time was even further reduced as was patient discomfort. The nagging issue that plagued cataract surgeons was to be able to eliminate the need for eye glasses after the surgery. To that end, stronger implants have been developed, multi focal, UV absorbing IOLs and many other options have been employed. Some have worked well, while others have failed. A most troublesome residual problem has been how to correct astigmatism after this surgery. At first, eye glasses had to be worn to correct the uncorrected astigmatism. Then some surgeons advocated making incisions in the cornea to reduce or eliminate the astigmatism post surgically. While this therapeutic approach was fairly successful, most patients did not want an additional procedure if note needed.

Recently, the astigmatic problem has now been solved. The STAAR Toric IOL is now available, and can correct up to 3.50 diopters of corneal astigmatism. That means that most people that have astigmatism before surgery can choose to have this new IOL implanted at the time of surgery, and have their astigmatism corrected resulting in no need for distance eye glasses after the procedure. The implant works similarly to a toric contact lens. When seen in the eye, there are peripheral markings to evaluate the positioning of the lens. The results thus far have been very good with only a few patients complaining about glare. These implants are not covered by most insurance companies and there fore must be paid for by the patient.

Always ask your surgeon about the options for implants before surgery to see if there is something that will best suite any visual needs.