Vision Center is funded by our readers. We may earn commissions if you purchase something via one of our links.
In this article
Corneal ectasia is the thinning of the cornea. The cornea is a curved layer of transparent tissue in the eye. It protects the iris and pupil and allows light to enter.
The cornea controls the entry of light and focuses it on the retina. This makes it possible to see things clearly.
The types of corneal ectatic disorders are:
Laser in-situ keratomileusis (LASIK) is a procedure that corrects vision problems. It is the most popular and most commonly performed corneal refractive surgery.
Post-LASIK ectasia is a rare complication that affects 0.02% to 0.6% of people who undergo LASIK.1
It can cause progressive myopia and astigmatism, leading to worsening eyesight.
Before the procedure, your doctor will assess you to see if you are a suitable candidate. The ophthalmologist will also discuss the benefits and risks of LASIK surgery.
LASIK uses a special laser to cut and shape the cornea. If too much corneal tissue is removed or becomes damaged, it can cause ectasia.
People with pre-existing corneal problems may also develop post-surgical corneal ectasia.2
Factors that increase your risk for post-LASIK ectasia are:1,2
The eye surgeon may recommend alternative treatments if LASIK surgery puts you at higher risk for corneal ectasia.
The eye is comprised of different fluids. Your cornea is one of many structures that keeps them in the right place.
If it becomes too thin, fluid from inside the eyes can enter the cornea. Damage to the cornea may also cause swelling and fluid to build up within its layers.
Most corneal ectasias are present in families. This suggests it is a hereditary condition.3,4
Corneal trauma is another possible cause. External factors such as eye surgery, contact lenses, and frequent and aggressive eye rubbing have been associated with ectasia.3,4,5
Other factors that increase your risk for cornea ectasia are:
The symptoms of corneal ectasia can vary for each person. It usually depends on the damage sustained by the cornea.
Common cornea ectasia symptoms include:
Age can help you determine when these symptoms will appear.
For instance, keratoglobus is prevalent in early life. Keratoconus usually affects people in their 20's and 30's. Meanwhile, PMD is more common for those in their 30's to 50's.
People with PMD and TMD ectasia may be asymptomatic and not develop most of these symptoms.7,8
However, a person with corneal ectasia will generally experience worsening vision. Unless treated, it can lead to vision loss.
Some visual disturbances and eye discomfort are normal after LASIK surgery. But if the symptoms persist for several weeks, you may have a post-LASIK corneal ectasia.
Post-LASIK ectasia has the same signs and symptoms as other types of corneal ectasia.
However, these symptoms may not show until after a few months or years since you had LASIK surgery.6
An eye specialist will conduct tests to check for signs and symptoms of corneal ectasia.
To find out your risk for corneal ectasia, your doctor may ask questions about:
A doctor will examine you for the following:
These tests can help diagnose corneal ectasia:
The keratometer used to perform this test measures the radius of the corneal curvature. It predicts the focusing power of the cornea.
Keratometry helps doctors check for an irregular corneal surface. It can diagnose irregular astigmatism and corneal steepening.6
The imaging test maps the surface of the cornea. It can help your doctor check for distortions on its curvature.
Corneal topography can diagnose keratoconus, pellucid marginal degeneration, and post-surgical ectasia.6
The non-invasive test takes cross-section images of front part of the eye, including the cornea.
Since these are high-resolution images, a doctor can easily check the size, thickness, and shape of different corneal structures.
OCT can be used in the diagnosis of keratoconus, acute corneal hydrops, corneal edema, and corneal scarring.6
The simple test measures corneal thickness at different points. Doctors may use it to diagnose corneal ectasia.6
Once the doctor confirms your diagnosis, you can choose from several treatment options:
Glasses can correct mild cases of non-progressive corneal ectasia. Studies show that eyeglasses can improve your vision by up to 20/20 or 20/40.6
The ophthalmologist may prescribe different lenses, depending on your diagnosis:
Corneal collagen cross-linking is a minimally-invasive surgical procedure. It slows down the thinning of the cornea in progressive forms of ectasia.
With that said, it can be used to treat mild to moderate cases of keratoconus and post-surgical corneal ectasia.6
A surgeon may perform epithelium-off, which involves the removal of the outermost layer of the cornea. But they may also decide to keep it with an epithelium-on procedure.
Next, the eye surgeon will apply riboflavin (vitamin B2) solution to the eye. Then they will use a mild ultraviolet light to activate the nutrient.
CXL strengthens and stabilizes the cornea, which helps delay corneal thinning.
It is a minimally-invasive procedure that involves the insertion of ring segments into the cornea. These are small, clear, and crescent-shaped implants.
An intracorneal ring can flatten abnormally steep cornea. It treats post-LASIK ectasia and keratoconus.9
Some eye surgeons combine IRCS with CXL to improve outcomes.
Corneal transplantation or keratoplasty is an invasive eye surgery. It is the mainstay treatment for severe corneal ectasia.
Keratoplasty is an option if optical devices like eyeglasses and contact lenses no longer correct your ectasia.
There are two types of corneal transplants:
Most surgeons prefer lamellar keratoplasty if the back of the cornea is healthy.
In this article
All Vision Center content is medically reviewed and fact-checked by a licensed optometrist to ensure the information is factual and meets industry standards.
We have strict sourcing guidelines and only cite from recent scientific research, scholarly articles, textbooks, government agencies, optometry websites, and medical journals.