Keratoconjunctivitis Sicca (KCS), or dry eye syndrome, is a common condition in which dryness of the eyes causes symptoms of ocular discomfort. This could result from an insufficiency of tears or an imbalance in the tear film. Refractive surgery can aggravate dry eyes, so it’s important to consider eye exam pre-operatively.
Dry Eye Symptoms
Dry eye symptoms are numerous and include the following:
- Discomfort of the eyes
- Stinging of the eyes
- Burning of the eyes
- Scratchiness of the eyes
- Redness of the eyes
- Watery eyes
- A feeling that something is in the eye
- Blurry vision
- Fluctuations in vision
These symptoms overlap with many eye conditions, so seeing an eye doctor is essential to get a proper diagnosis.
Dry Eye Causes
Dry eyes can be caused by tear insufficiency or imbalance. The tear film is made up of three layers: the watery aqueous layer, the mucus-like mucin layer, and the oily lipid layer. These three components must be in balance for the tear film to be stable.
Decreased Tear Production
When tears are not produced in sufficient amounts, the eyes will dry out. One condition that causes this is called Sjogren’s syndrome. Sjogren’s is an autoimmune disease that causes dryness of the eyes, mouth, and nose, along with arthritis and other issues in the body. There are other reasons, aside from Sjogren’s, that can cause insufficient tear production, including certain medications.
Increased Tear Evaporation
The vast majority of people with dry eye syndrome struggle with increased tear evaporation. The lipid layer of the tear film, produced by the meibomian glands in the eyelids, serves to prevent the evaporation of tears. When there is meibomian gland dysfunction, dry eye can become an issue because all the tears that are produced rapidly evaporate.
Risk factors for dry eye include:
- Female gender
- The environment
- Malposition of the eyelids
- Contact lens wear
- Refractive surgery
Dry Eye Treatments
Dry eye treatment varies depending on the individual patient. Here are some of the treatments that are commonly recommended:
- Artificial tears
- Lubricating gels
- Lubricating ointments
- Punctal plugs
- Prescription eye drops
- Amniotic membranes
- Thermal pulsation
- Intense pulsed light (IPL)
- Surgery to correct problems with eyelid positioning
What Is PRK?
PRK stands for photorefractive keratectomy. It’s a type of refractive surgery used to reshape the cornea to correct myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. During the recovery from surgery, a bandage contact lens is worn over the eye to help with healing.
What Is LASIK?
LASIK stands for laser-assisted in situ keratomileusis. Like PRK, it’s a refractive surgery technique used to reshape the cornea. Its goal is also to correct myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. There is no need for a bandage contact lens during the healing process, as the flap created during surgery acts as a suitable substitute.
PRK For Dry Eyes
There are several reasons why a surgeon might recommend PRK over LASIK for a particular patient. The most common are thin corneas or levels of correction. There are key differences in the surgical technique used in LASIK versus PRK. Unlike PRK, LASIK doesn’t involve the creation of a flap in the cornea. In PRK, the outer layer of the cornea, called the epithelium, is removed. Then, laser treatment is applied to the deeper layers of the cornea. After surgery, a bandage contact lens is worn over the cornea until the epithelium grows back. The absence of a flap is thought to be the reason for the diminished risk of dryness in PRK. The flap is thought to be disruptive to the cornea nerves, contributing to dryness. For that reason, PRK and dry eye commonly go hand in hand.
LASIK For Dry Eyes
You might wonder, is LASIK safe for dry eyes? Generally, the answer is yes, depending on the severity of the dryness. Post-surgical dryness improves over time for most people. There is, however, a small risk of LASIK-induced neurotrophic epitheliopathy (LNE), which is a complication in which instability of the corneal epithelium leads to prolonged dryness. This can cause discomfort and blur as it heals, which can take up to 6 months.
Lipiflow For Dry Eyes
Regardless of whether you are pursuing LASIK or PRK, you’ll want to treat any pre-existing dry eye prior to undergoing surgery. If your meibomian glands are thought to be functioning less than optimally, you’ll want to consider thermal pulsation treatment, such as Lipiflow. Lipiflow uses heat and pressure on the eyelids to unblock the meibomian glands so they can secrete the lipid layer of the tear film more effectively.
If you’re contemplating LASIK options for dry eyes, just know that they’re out there. Experiencing dry eyes doesn’t preclude you from having refractive surgery. Your initial consultation will determine which procedure is safest for you. If you’d like to discuss LASIK PRK dry eyes or anything else relating to refractive surgery, call the Kraff Eye Institute to schedule your appointment today.