Managing Keratoconus: From Diagnosis to Scleral Lenses

Keratoconus is a condition that tends to appear gradually, hiding behind changing prescriptions and complaints that could belong to a dozen other conditions. My clinical approach to keratoconus starts with a simple premise: I screen every patient, every time. Just as we roll out dry eye evaluation universally, keratoconus screening cannot be reserved for patients who seem like obvious candidates. The condition is far more prevalent than historically assumed,¹ and improved imaging technology has confirmed what many of us have suspected: we were missing it.

What I Look for When Screening for Keratoconus

In any comprehensive exam, several findings raise my index of suspicion. A change in glasses or contact lens prescription warrants attention. An increase in astigmatism, particularly if it is progressive, should prompt further investigation. When I perform retinoscopy, I look for a scissors reflex (ie, the characteristic pattern of light motion that suggests irregular corneal anatomy). I also pay close attention to automated keratometry and auto-refraction findings, which can themselves reveal irregularity before any other finding appears.

On the patient history side, I ask about sleep apnea, allergies, atopy, Down syndrome, and Marfan syndrome. Each of these conditions carries an elevated risk for keratoconus. Eye rubbing is a critical question. It is one of the most modifiable risk factors, and I consistently counsel patients about how to avoid it. Family history of keratoconus is a clear trigger for more thorough evaluation, including imaging.

Imaging with corneal tomography such as the Pentacam (Oculus) provides extremely valuable information. Looking at both anterior and posterior corneal surfaces, and specifically evaluating posterior surface elevation and corneal thickness distribution, gives me information that keratometry and topography alone cannot. Keratoconus starts at the back of the cornea, and posterior surface changes will precede the anterior findings that tend to catch our attention first. I do not wait for the cornea to appear abnormal before I act.

The prevalence data support vigilance. A study by Harthan et al found that keratoconus is significantly more common than classic estimates suggested, a finding tied directly to improvements in posterior corneal imaging.² Since we can now measure what we previously could not, diagnoses have increased. That is not an epidemiologic shift; it is a detection shift. I recommend imaging all patients with any risk factor, any change in refraction, or any clinical finding that does not add up cleanly.

Counseling Patients Through a Keratoconus Diagnosis

How I introduce a keratoconus diagnosis matters. The condition is lifelong, and patients who understand it from the beginning are far more likely to follow up consistently and make informed decisions about treatment. I aim to inform without frightening. Keratoconus is manageable. We have excellent tools. But patients need to understand what progression looks like and why monitoring matters.

I direct patients to the National Keratoconus Foundation (NKCF), which produces a podcast called Clearly KC, a resource designed for both patients and practitioners. It covers the condition clearly and is something I actively recommend sharing. The NKCF website offers patient-facing education that I cannot replicate in a 10-minute conversation, and having that resource available for follow-up reading significantly improves comprehension and engagement.

Follow-up intervals depend on where a patient is in their disease. For a newly diagnosed, stable patient, a 6-month interval is standard. If progression is documented, I may bring a patient back at 3 or 4 months. For younger patients, particularly adolescents whose corneas tend to progress more rapidly, I follow up sooner and am more aggressive about recommending cross-linking. One practical tip that has served me well: when I see a new patient with keratoconus, I request prior records even if keratometry was not previously performed. A prescription history showing consistent change over time can suggest progression even without imaging comparisons.

Cross-Linking: When to Act and What to Expect

The purpose of corneal cross-linking is to halt disease progression and stabilize the cornea before further thinning and steepening compromise long-term visual potential. This is the first point I emphasize with patients who are candidates for the procedure. Cross-linking is not a refractive treatment. Unlike LASIK or PRK, it is not designed to directly improve vision or eliminate the need for glasses or contact lenses. Its primary goal is to preserve the cornea’s structural integrity and reduce the risk of future progression. Patients who understand this distinction are more likely to have realistic expectations and feel motivated to proceed with timely treatment.

In terms of timing, I err on the side of earlier intervention. A younger patient with confirmed progression is a strong candidate. The corneas of young individuals progress more rapidly, and delaying cross-linking means permitting avoidable deterioration. I also counsel female patients of childbearing age specifically that keratoconus can progress during pregnancy and does not fully regress postpartum. If a patient is planning to become pregnant, the timing of my recommendation is shaped by that conversation.

Two approaches are available: epithelium-off cross-linking, which remains the most established and the initial FDA-approved procedure, and epithelium-on cross-linking, which avoids epithelial removal and is the newest FDA-approved procedure. Multiple cross-linking techniques are also emerging, and I stay current with the literature as the landscape evolves.

Scleral Lenses: Evolution in Design and Expanding Indications

Scleral lenses were once associated almost exclusively with keratoconus. That is no longer the case, and the growth has been remarkable to observe over the past two decades. Today, scleral lenses are used for irregular astigmatism across all its causes, for ocular surface disease, for regular corneas with presbyopia, and for patients who simply cannot achieve adequate comfort or vision with soft lenses. Keratoconus initially drove interest in scleral lenses, but today they are used to manage a wider range of indications than ever before.

The designs themselves have advanced substantially in the past 10 years. One of the most significant changes is the widespread availability of back surface toricity. According to research by DeNaeyer and the Scleral Shape Study Group, only about 5.7% of eyes have a spherical scleral profile.³ The vast majority require correction for scleral shape on the lens’ back surface, and diagnostic sets now commonly incorporate that geometry. The practical result is better centration, improved comfort, and reduced over-refraction, which in turn supports better performance of scleral lens designs, including multifocals.

Quadrant-specific designs have added another layer of precision. Rather than applying a uniform correction across the scleral landing zone, these designs allow independent adjustment of each quadrant, accommodating toric and irregular scleral shapes without disturbing the central optics. This is particularly useful in patients who previously required large residual astigmatic corrections in their over-refraction.

Scleral profilometry has changed the fitting process itself. Instruments that measure not just the cornea, but the full scleral conjunctival profile allow me to select an initial lens far closer to the final fit than was previously possible. Fitting efficiency has improved, patient chair time has decreased, and outcomes are more consistent. My patients wear their lenses longer and report better comfort at the end of the day.

Scleral Lens Education: What Patients Need to Know

Handling is the first and most important topic. The application and removal of a scleral lens are learned skills, and patients need hands-on instruction. The Scleral Lens Education Society offers resources I regularly reference and share. Application requires a plunger-style applicator and proper head positioning; removal requires a separate technique. I do not assume that a patient who has worn soft lenses will intuitively adapt to scleral handling.⁴ We walk through it together and confirm competency before a patient leaves the office.Solutions matter significantly with scleral lenses. The bowl of the lens is filled with a preservative-free saline or artificial tear solution before application. Preserved solutions can cause significant problems. Corneal exposure to preservatives trapped beneath a large-diameter lens is not trivial. I counsel every patient who wears scleral lenses on this and do not leave it to guesswork.

Replacement schedule is a common point of confusion. Scleral lenses are not monthly or even quarterly replacement devices. The standard is a 6-month or yearly evaluation with replacement every 1 to 3 years, depending on lens condition. Wear and tear, surface scratching, and material changes over time affect optical quality and should prompt replacement on a reasonable schedule. I built this expectation into the initial education.

Beyond Keratoconus: A Broader Lens

One finding that still surprises colleagues: I regularly see patients who have had cataract surgery without a prior keratoconus diagnosis. They present with suboptimal visual outcomes and an irregular corneal surface that had never been addressed before their IOL was placed. This is a reminder that keratoconus screening cannot be reserved for young patients. Corneal imaging in a patient before or after cataract surgery is essential.

I also want to note that scleral lenses are not limited to irregular corneas. Studies show improved vision, comfort, and patient preference for scleral lenses compared with soft toric lenses in patients with regular astigmatism.⁵ Patients who struggle with soft lens comfort, particularly those with dry eye or presbyopia, deserve to know that the option exists. Part of my responsibility is educating my patients to inform them of their options.

The Bottom Line

Keratoconus management rewards consistency. Screening every patient, imaging thoughtfully, counseling clearly, and acting on progression before it becomes difficult to reverse—these are the practices that produce good outcomes over a career of patient care. The tools are available. Scleral lens technology has never been better. Cross-linking gives us a way to stop the disease in its tracks. What remains is the commitment to look carefully enough to find it.