What’s New in Keratoconus Treatment? A 2024 Update

Keratoconus is an eye condition in which the cornea—the clear, dome-shaped front surface of your eye—starts to thin and bulge outward into a cone shape. This ectasia (distension) disrupts corneal biomechanics, changing the way light enters your eye, sometimes leading to distorted, blurred vision. Keratoconus vision is like looking through a warped window instead of a flat piece of glass.

Keratoconic corneas are more common in adolescents and young adults than in older adults. In the early stages, specialized contact lenses may help correct corneal curvature and improve vision, but keratoconus can worsen as you age, often until age 40.

In more progressive keratoconus cases, surgical options, such as corneal transplants or corneal cross-linking surgery, may be considered to halt corneal scarring and thinning. Here, we review some of the advances in the treatment and management of keratoconus in the past year.

Early diagnosis of keratoconus is key

Previously, keratoconus was challenging to diagnose at an early stage, so it was considered one of the rarer corneal diseases. However, advances in keratoconus diagnosis now allow us to begin treatment earlier and more conservatively.

Technologies such as Scheimpflug imaging, keratometry readings, slit-lamp exams, and optical coherence tomography allow detailed examination of the ocular surface and front section of the eye; this allows us to act to slow the progression of keratoconus before drastic corneal distension occurs.

Potential indicators of the condition, such as irregular epithelial thickness or even the slightest thinning of the corneal stroma (measured using corneal pachymetry), can help identify keratoconus before major vision changes occur. One such test, the Belin/Ambrósio Display, is able to show changes in corneal shape earlier than ever, detecting keratoconus before patients notice significant changes in their vision.

Correcting vision problems caused by keratoconus

Corrective lenses can help with the refractive errors caused by keratoconus (such as myopia and irregular astigmatism), but they’re not a cure. Soft contact lenses can improve visual acuity, but the prescription changes frequently as the shape of the eye changes. Hard contact lenses can help with more advanced keratoconus but are often uncomfortable. For very irregularly shaped corneas, there are scleral lenses, which are contact lenses that rest on the white of the eye and bridge over the cornea.

When the condition affects the vision, refractive surgery options are typically recommended for keratoconus treatment. Such as the implantation of intracorneal ring segments (ICRS) to help reshape the cornea so that contacts can be worn. Or, Topography-guided custom ablation treatment (T-CAT) surgery, which also aids contact lens wearing.

If there is too much scarring and thinning, a corneal transplant may be necessary. Transplanting either the cornea’s top layer (deep anterior lamellar keratoplasty or DALK) or performing a full-thickness transplant (penetrating keratoplasty or PK) replaces damaged corneal tissue with healthy tissue.

The latest in keratoconus treatment

There is no known cure for keratoconus. As the corneal stroma weakens and thins, collagen fibers that help hold the cornea’s shape degrade, and keratocytes, which are responsible for maintaining the cornea’s structure for light refractivity, decrease. Currently, there is no way to reverse these symptoms and permanently restore the cornea’s shape.

However, recent discoveries in early interventions may be able to slow the progression of the disease, potentially staving off more invasive surgical procedures for longer.

Keratoconus and the Dresden protocol: advancements beyond disease progression

Corneal collagen cross-linking (CXL) is the only treatment to prevent the worsening of keratoconus and is approved by the Food and Drug Administration (FDA).

The Dresden protocol (the original form of CXL) has been the gold standard treatment for keratoconic eyes for over 20 years. This procedure involves removing the top layer of the cornea (epithelium), infusing it with a riboflavin solution, and then strengthening the cornea with ultraviolet-A light; this stiffens the cornea, helping it resist doming and slows or stops the progression of keratoconus.

However, it’s a slow process, as the riboflavin solution is applied every 1 to 3 minutes for 15 minutes and then again at this rate during the 30-minute ultraviolet-A light exposure. It may also cause discomfort.

Accelerating corneal cross-linking: faster and equally effective treatments

Recent advances in CXL have sped up the process, lessening the problem of oxygen depletion, an essential component in the treatment. A breakthrough new protocol gives the same results as the Dresden method but in much less time — only 9 minutes and 15 seconds of UVA irradiation compared to 30 minutes.

Breakthrough in epi-on cross-linking: improving patient comfort and safety

The Dresden protocol is an epithelium-off (epi-off) procedure, as it removes the corneal surface, which can cause discomfort and increase infection risk. Recent advances have led to a method that allows the epithelium to remain intact (epi-on) during CXL surgery, reducing these risks.

Innovations for ultra-thin corneas

The traditional Dresden protocol isn’t suitable for those with very thin corneas. For those patients, new methods disrupt the top layer of the cornea, allowing the riboflavin solution to penetrate. These include using a hypo-osmolar solution to swell the cornea, after which a special contact lens soaked in riboflavin is placed on the eye. A more recent approach (the sub400 individualized cross-linking approach) adjusts the treatment based on corneal thickness, making it safer and more effective for keratoconus patients with thin corneas.

Advanced penetration enhancers and specialized UV irradiation have also been used to improve the epi-on method. Penetration enhancers allow the riboflavin to pass through the cornea more easily. Iontophoresis, which uses electrostatic forces, can also aid riboflavin penetration. However, due to the varied swelling of keratoconus corneas, these procedures have mixed results. In the United States, there are currently no FDA-approved epi-on cross-linking procedures.

Next-generation customized treatment for keratoconus

A significant advancement in keratoconus treatment is customized cross-linking, which tailors the treatment based on the specific characteristics of the cornea. This approach has shown promising results in flattening the cornea and improving visual acuity without the need for bulky and expensive equipment.

PTK-assisted customized epi-on corneal cross-linking (PACE) uses various modalities to halt keratoconus while also improving vision. A map of the corneal topography guides an excimer laser to remove a tiny part of the epithelium in what is known as a mixed epi-on/epi-off procedure. This treatment allows the solution to penetrate the stromal layer while also ensuring there is enough oxygen. More UV energy is applied to the tip of the corneal cone than is applied to the entire cornea in the Dresden protocol. Early clinical trials of PACE show a better corneal flattening effect and better visual outcomes with less corneal tissue being removed.

The future of corneal treatment, advancing patient outcomes

As these new techniques and technologies continue to be refined, they hold the promise of even better outcomes for patients with keratoconus. The field of ophthalmology is evolving rapidly, and these advancements are a testament to the ongoing improvements in eye health and vision quality.

Can you prevent keratoconus?

Unfortunately, there is no known prevention for keratoconus. Although CXL can slow down the disease’s progression, it is not a cure for keratoconus or a preventive treatment.

Looking for a keratoconus specialist nearby? Choose Assil Gaur Eye Institute for the treatment of keratoconus

The Assil Gaur Eye Institute team of ophthalmologists are experts in corneal eye disease and its management. Dr. Assil’s leadership in corneal transplantation surgery began while serving on the university faculty in St. Louis decades ago in one of the largest corneal transplant practices in the United States.

Dr. Assil and his team have performed thousands of corneal transplants and are nationally recognized leaders in the field.

The doctors at AGEI ophthalmology group have a combined 100 years of experience and are nationally recognized specialists in treating glaucoma, macular degeneration, and diabetic retinopathy.

This is one reason why Los Angeles Magazine names Assil Gaur Eye Institute one of the top ophthalmology eye centers in Los Angeles year after year.

We are conveniently located for patients throughout Southern California and the Los Angeles area in or near Beverly Hills, Santa Monica, West Los Angeles, West Hollywood, Culver City, Hollywood, Venice, Marina del Rey, Malibu, Manhattan Beach, and Downtown Los Angeles.

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