Cornea, External Disease and Refractive Surgery
Physicians
Bhairavi Kharod Dholakia, MD
Joung (John) Kim, MD
J. Bradley Randleman, MD, director
Sheetal M. Shah, MD
Dr. Kim and Randleman specialize in providing state-of-the-art care for patients with problems related to the cornea and adjacent structures, cataracts, and for those patients seeking refractive surgery, to reduce or eliminate their need for glasses or contacts for everyday life activities. Dr. Dholakia's special interests include corneal and external disease, corneal transplants, refractive surgery and cataract surgery. Dr. Shah's areas of clinical interest are: corneal and external disease management, corneal transplants, cataract surgery and general eye care.
The Cornea
The cornea is the transparent front segment of the eye covering the iris, pupil and anterior chamber. It provides most of the eye’s optical power. Often called the “window to the world,” the cornea serves two vital functions: protecting the eye from infection and trauma and serving as the major refractive surface responsible for bringing light rays into focus so that we can see objects clearly. When light strikes the cornea, it bends (refracts) incoming light through the lens and onto the retina to bring images into clear focus.
The cornea’s tissue consists of five basic layers: epithelium, Bowman’s layer, stroma, Descemet’s membrane and endothelium. Unlike most tissues in the body, the cornea contains no blood vessels. It receives nourishment from the outside air, our tears, and aqueous humor, a liquid substance that fills the front chamber of the eye.
Cornea specialists at the Emory Eye Center utilize the latest techniques and advances in the field to treat simple and advanced problems caused by disease, genetic predisposition, injury or aging to the structures in the front regions of the eye. These include cataracts (when the natural lens inside the eye becomes cloudy and blurs vision), keratoconus, corneal abrasions, other conditions that affect the outer layers of the eye, and refractive errors such as nearsightedness, farsightedness, and astigmatism.
There are a number of medical and surgical treatments available to our patients, and our cornea specialists at the Emory Eye Center offer the widest possible range of treatment options, directly suited to match each patient’s unique conditions. When surgery is indicated, the most commonly performed procedures include cataract and refractive surgery, and a variety of corneal transplantation techniques.
For appointments or more information about our physicians, please contact the Emory Eye Center Call Center at 404-778-2020.
Surgery Types
Cataract Surgery
During cataract surgery the natural lens of the eye, which has become cloudy and is negatively affecting vision, is removed and replaced with a new artificial lens that improves focus and clarity for the vast majority of patients. Many patients achieve functional vision for distant objects without the need for strong glasses; however, most cataract surgery patients will still need reading glasses for near work— including reading, seeing the computer, and other tasks in this close range. In addition to standard intraocular lenses, today there are new replacement lenses that can function for both distance and near vision in properly selected patients. There are also lenses that can reduce astigmatism, which also improves the quality of vision at all distances. It is very important to match the correct lens type with each individual, and a complete evaluation by your surgeon will help determine what lens option is best for you. Find more information at Eye Conditions | Cataracts.
Refractive Surgery
Refractive eye surgery is intended to improve the eye’s ability to focus clearly without the need for glasses or contact lenses. There are a variety of different surgical options available, and these are matched to the individual’s needs to provide the best possible outcome. In addition to LASIK, the most common procedure performed today, there are a variety of other available techniques including other corneal surgeries and intraocular surgeries for appropriate candidates.
LASIK
Laser in Situ Keratomileusis ("LASIK") is a laser procedure that can correct myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. LASIK involves creating a protective flap from the outside layer of the cornea and reshaping the middle layer of the cornea with the ultraviolet laser energy to correct refractive error and improve vision. The FDA ophthalmic devices advisory panel recommended FDA approval for the LASIK procedure using a surgical system developed by Emory cornea surgeons in the late 1990’s.
Bringing their combined years of experience and academic expertise to the table at Emory Eye Center’s refractive surgery center, Emory Vision's physicians, located at the Emory Perimeter Clinic, provide a superior experience to anyone interested in improving their vision. They use the most advanced diagnostic and surgical techniques to confirm candidacy for surgery and match the individual with the best surgical option available for them.
PRK (Photorefractive Keratectomy)
PRK or photorefractive keratectomy is another type of corneal laser eye surgery, also used to correct myopia, hyperopia, and astigmatism in much the same way as LASIK. With PRK the excimer laser reshapes the cornea in exactly the same way as with LASIK, but in this procedure the surgery is performed on the surface of the eye rather than underneath a flap. Healing time can be more prolonged after PRK, but the long-term outcomes are identical between LASIK and PRK, and this can be an excellent choice for some patients.
Phakic Intraocular Lens Implants
Phakic intraocular lens surgery implants a lens within the eye to improve vision in patients with more extreme amounts of nearsightedness or in patients that are otherwise not deemed good candidate for LASIK or PRK. There are different lens types available; some of these are positioned in front of the iris (colored portion of the eye) or just behind the iris in front of the patient’s natural lens. These lenses can provide excellent quality of vision and are an ideal choice for the appropriate patients.
Refractive Lens Exchange (RLE)
RLE is nearly identical to cataract surgery and replaces the eye’s natural lens with an artificial lens to improve focusing of the eye. This is yet another refractive surgery alternative for the appropriate patient. The lenses available for refractive lens exchange are the same as for cataract surgery, with the ability to focus clearly at one distance or multiple distances, and the ability to correct astigmatism for selected individuals.
Corneal Surgery
Corneal Transplantation
A corneal transplant is indicated where there is a diseased or damaged cornea that is blocking the cornea’s ability to transmit light to the retina. When indicated, the patient’s cornea is replaced by donor cornea or graft. There have been many improvements over the past few years in corneal transplantation surgery, and the surgeons at Emory Eye Center are now able to transplant only the tissue needed to improve corneal function. In some instances the entire cornea still needs to be transplanted, a procedure called penetrating keratoplasty, but in many instances only the inner layer of the cornea is damaged and needs to be replaced in a procedure called Descemet’s stripping endothelial keratoplasty or DSEK. Finally, there are conditions in which only the front portion of the cornea is damaged, and in these cases a procedure called deep anterior lamellar keratoplasty or DALK may be appropriate. The most common conditions necessitating corneal transplant include a genetic disorder similar to premature aging of the cornea called Fuchs corneal dystrophy; disorders affecting the shape and clarity of the cornea, including keratoconus; and trauma, infections, or other disorders that cause the cornea to become scarred and cloudy, such as infections from improper contact lens wear, trauma, and genetic dystrophies.
DSEK
Descemets stripping endothelial keratoplasty (DSEK) is the procedure of choice for disorders affecting only the innermost region of the cornea that result in corneal swelling limiting vision. In the DSEK technique only the innermost corneal layer is transplanted through a small wound, and the graft does not require sutures to hold it in place. Visual recovery is usually faster for DSEK than for full thickness penetrating keratoplasty, and most patients are able to achieve their best vision with a mild pair of glasses after surgery.
Penetrating Keratoplasty (PK)
Penetrating keratoplasty is corneal transplantation technique that has been performed for the longest periods of time, since 1947, and remains an excellent surgical option for patients that require the whole cornea to be replaced. This surgery requires multiple sutures to hold the graft in place after surgery, visual recovery is prolonged, and in many cases patients achieve their best vision after surgery with the use of contact lenses. Emory Eye Center has on its faculty two of the most talented and experienced contact lens fitters in the nation. Under their care, corneal transplant patients are in excellent hands when it comes to the final steps of restoring vision.
