Keratoconus: What It Is and How We Treat It
Understanding Keratoconus
Knowing what keratoconus is and how it develops helps you take an active role in your care. This condition is different from common refractive errors like nearsightedness because it involves a physical change in the cornea's structure, not just its focusing power.
In a healthy eye, the cornea holds a smooth, rounded shape that focuses light cleanly onto the retina at the back of the eye. In keratoconus, the cornea thins near its center and gradually pushes forward into a cone shape. This irregular shape scatters light instead of focusing it, which causes blurred and distorted vision.
- The cornea thins and steepens near its center
- The shape becomes irregular and cone-like over time
- Both eyes are usually affected, though one often progresses faster than the other
- Vision can shift gradually over months or years
Keratoconus most often begins in the late teens and can continue to progress into the thirties. Young adults with a family history of the condition, chronic eye allergies, or a habit of rubbing their eyes are at higher risk. Certain systemic conditions, including Down syndrome and some connective tissue disorders, are also associated with a greater likelihood of developing keratoconus. Both men and women can be affected.
Repeated eye rubbing puts mechanical stress on the cornea and is considered one of the most important modifiable risk factors for keratoconus progression. Patients with seasonal or year-round allergies are especially vulnerable because itching creates a constant urge to rub. Managing allergies with the help of your eye care team can reduce this trigger and may help keep the cornea more stable over time.
Symptoms of Keratoconus
Symptoms can be subtle at first and easy to dismiss as ordinary vision fluctuation. Because keratoconus tends to progress slowly, recognizing the pattern of changes is often more important than any single symptom on its own.
In the early stages, vision may blur slightly and glasses prescriptions may seem to change more often than expected. Some patients notice mild distortion around bright lights at night, or that straight lines appear slightly wavy. These early changes often feel minor and can be mistaken for screen fatigue or mild nearsightedness.
As keratoconus advances, glasses can no longer provide consistently sharp vision. A phenomenon called ghosting, where a single object appears as multiple overlapping images, becomes more common. Glare and halos around headlights can make nighttime driving difficult and uncomfortable. Because each eye may be at a different stage, many patients also experience noticeable differences in how each eye sees.
In advanced cases, the cornea may develop scars that cause permanent blur that cannot be corrected with lenses alone. A rare but serious event called corneal hydrops can occur when the inner layer of the cornea tears, leading to sudden pain, redness, and a sharp drop in vision. Corneal hydrops usually heals over several weeks but often leaves a scar. If you experience sudden eye pain with a significant loss of vision, seek care promptly.
Diagnosing Keratoconus
An accurate diagnosis depends on more than a standard vision check. Our Cornea Specialists use advanced imaging tools to map the cornea in precise detail and to detect changes that may not yet be visible to the naked eye.
Corneal topography creates a detailed map of the cornea's surface shape, allowing our team to spot irregular steepening even before symptoms become noticeable. Corneal tomography goes further by measuring the thickness of the cornea at many points throughout its layers. Together, these tools are essential for confirming a diagnosis and for detecting early-stage keratoconus in patients who are still largely symptom-free.
Anterior segment OCT, a type of imaging that produces layer-by-layer images of the cornea, can give our team a detailed view of structural changes within the tissue. Wavefront analysis measures higher-order optical errors that glasses cannot correct. A thorough history, including any family history of keratoconus and the presence of allergies, is also an important part of evaluation.
Because some patients progress quickly while others remain stable for years, repeat imaging at regular intervals is a critical part of keratoconus management. Comparing a series of topography and tomography scans allows our team to determine whether the disease is active or holding steady. This information directly guides treatment decisions, including whether and when corneal cross-linking may be appropriate.
Contact Lens Options for Keratoconus
For many patients, the goal of contact lens fitting is to create a smooth optical surface over the irregular cornea, restoring useful vision without surgery. Our integrated team of Cornea Specialists and optometrists works together to find the right lens for each patient's corneal shape and lifestyle.
In mild keratoconus, standard glasses or soft contact lenses may provide acceptable vision. As the cone becomes more pronounced, however, both glasses and soft lenses struggle to conform to the irregular surface, and vision quality tends to decline. At that point, a more specialized lens design is usually recommended.
Rigid gas-permeable (RGP) lenses are firm lenses that create a smooth, tear-filled layer between the lens and the cornea. This effectively neutralizes much of the cornea's irregular shape and provides sharper vision than soft lenses for many keratoconus patients. Our optometry team, including specialists with decades of experience fitting RGP lenses for irregular corneas, can evaluate whether this option is right for you.
Scleral lenses are larger specialty lenses that rest on the white part of the eye, called the sclera, and vault completely over the cornea. The fluid-filled space beneath the lens corrects for the cornea's irregular shape and provides both comfort and clear vision, even in moderate to severe keratoconus. Dr. Paul Zerbinopoulos has been fitting scleral lenses for corneal conditions since 2008, and Dr. Earle Scharff brings over 40 years of optometry experience to specialty lens care. A precise, individualized fitting process is essential to getting the best result from scleral lenses.
Surgical and Medical Treatments
When contact lenses are no longer able to manage keratoconus, or when the disease is actively progressing, our Cornea Specialists offer a range of evidence-based treatments to stabilize or restore vision. Every treatment plan is tailored to the individual patient's stage of disease and overall eye health.
Corneal cross-linking (CXL) is a procedure that uses riboflavin eye drops combined with UV light to create new bonds within the corneal tissue, making it more rigid and resistant to further bulging. The primary goal of cross-linking is to stop the progression of keratoconus, not to reverse the shape change that has already occurred. CXL is most effective when performed in patients with documented progression, particularly younger patients whose disease is still active. Dr. Elliot Perlman was the first ophthalmologist in Rhode Island to offer FDA-approved corneal cross-linking, and he remains a leading provider of this treatment for progressive keratoconus and corneal ectasia.
When keratoconus is too advanced to be managed with lenses or cross-linking, a corneal transplant can replace damaged tissue with healthy donor cornea. A full-thickness transplant, called penetrating keratoplasty, replaces the entire cornea. A partial-thickness approach, such as DALK (deep anterior lamellar keratoplasty), spares the inner corneal layers when they are still healthy, which lowers the risk of rejection. Recovery from corneal transplantation takes several months, and most patients achieve significantly improved vision following surgery. Dr. Jane Cook, Dr. Elliot Perlman, and Dr. Christopher Newton all perform corneal transplant procedures.
Intracorneal ring segments are small, curved implants placed within the cornea to flatten its cone and improve the fit of contact lenses. This procedure is reversible and can be a useful intermediate step for patients who are not yet ready for transplantation. Our Cornea Specialists evaluate each patient's corneal imaging and visual needs to determine whether ring segments or another approach is the best fit.
Living Well With Keratoconus
Keratoconus is a manageable condition for most patients, especially when it is caught early and followed carefully. Everyday habits and consistent follow-up care play an important role in keeping the cornea as stable as possible.
Avoiding eye rubbing is the single most important daily habit for anyone with keratoconus. Treating underlying allergies reduces the urge to rub and removes a significant source of corneal stress. Preservative-free artificial tears can ease dryness without irritating the eye surface, and UV-blocking sunglasses provide protection outdoors. Sleeping in contact lenses should always be avoided.
- Stop eye rubbing entirely, even when eyes feel itchy
- Address allergies with your eye care team to reduce itching
- Use preservative-free lubricating drops for comfort
- Wear UV-protective sunglasses outside
- Never sleep in contact lenses
Patients with stable keratoconus typically benefit from one to two monitoring visits per year. Those with more active disease or who have recently had cross-linking may need more frequent imaging to track how well the cornea is responding. Any sudden change in vision, new eye pain, or significant increase in redness warrants a prompt evaluation, not a wait-and-see approach.
Most patients with well-managed keratoconus lead full and active lives. Scleral lenses often provide vision quality that matches or exceeds what glasses can offer. Accommodations like adjustable screen brightness or larger-text displays can be helpful in academic or work settings when vision is still being optimized. For sports, protective eyewear such as sports goggles is advisable for any contact or high-impact activity, and anything that poses a direct risk of a blow to the eye should be approached with caution and appropriate protection.
Frequently Asked Questions
The following questions address some of the situations and decisions that keratoconus patients commonly face. If your question is not answered here, our team is happy to walk through your specific circumstances at your appointment.
The vast majority of patients with keratoconus retain useful functional vision throughout their lives. Legal blindness caused by keratoconus alone is uncommon. For patients whose disease reaches a severe stage, corneal transplantation is a well-established option that restores good vision for most people. Early detection and appropriate treatment, including cross-linking when indicated, greatly improve the long-term outlook.
LASIK is not appropriate for keratoconus patients. The procedure works by removing corneal tissue to reshape the surface, which further weakens a cornea that is already structurally compromised. Undergoing LASIK with undetected or untreated keratoconus can accelerate disease progression and cause serious vision problems. If you have been told you may have early keratoconus, or if you have a strong family history, it is essential to share that information with any surgeon before pursuing any laser vision correction procedure. Dr. Elliot Perlman, who has offered refractive surgery since 1994, and Dr. Christopher Newton can help evaluate whether you are a candidate for any vision correction procedure and guide you toward the safest path.
Cross-linking is designed to stop progression, not reverse the existing shape of the cornea. Some patients notice a modest improvement in vision after the procedure, but this is not the primary goal. The real benefit is that a stabilized cornea can continue to be fitted with contact lenses effectively, and it reduces the likelihood that a corneal transplant will be needed in the future. Vision correction through lenses can often be optimized after the cornea has stabilized following cross-linking.
If you have been diagnosed with keratoconus, your children have a higher risk of developing it than the general population. Baseline corneal imaging starting in the early teenage years is a reasonable precaution, since keratoconus most commonly begins during adolescence. Modern topography and tomography can detect subtle early changes that are not yet causing symptoms, which is exactly the window when cross-linking is most effective. Catching the disease before it progresses gives children the best long-term outcome.
Sudden severe pain combined with a sharp drop in vision may indicate corneal hydrops, a rare event where the inner layer of the cornea breaks down and fluid enters the tissue. This requires prompt evaluation by an eye care provider, ideally a Cornea Specialist, to assess the extent of the damage and manage the healing process appropriately. Do not wait for a scheduled appointment if you experience these symptoms. Our team offers guidance on accessing urgent eye care when time-sensitive situations arise.
The decision to move toward surgery is based on several factors: whether contact lenses can still provide acceptable functional vision, whether the cornea continues to progress despite cross-linking, and whether there is significant scarring affecting vision. This is not a decision made by a single test result alone. Our Cornea Specialists review your imaging over time, assess your visual quality, and discuss your daily vision needs with you before recommending any surgical intervention. The goal is always to preserve the most corneal tissue possible while maintaining the best quality of life.
Schedule a Cornea Evaluation at Rhode Island Eye Institute
If you have been told you may have keratoconus, or if your vision has been shifting and glasses are no longer giving you clear sight, our team is here to help. Rhode Island Eye Institute brings together fellowship-trained Cornea Specialists, experienced optometrists with deep expertise in specialty contact lens fitting, and advanced diagnostic imaging, all under one roof to provide seamless, individualized care. We are proud to serve patients throughout Rhode Island and southern Massachusetts, and we welcome you to schedule a consultation with our cornea team today.