Monocular Scleral Lens Patient Refit Into New Scleral Lens

Managing contact lenses for a patient with vision in only one eye requires careful planning and a high level of precision. At Insight Vision Optometry, Las Vegas, our specialty contact lens team regularly works with complex cases involving keratoconus, corneal scarring, and monocular vision. The following case highlights the unique challenges and considerations involved in refitting a monocular scleral lens patient.

Why Is a Monocular Patient’s Lens Fitting So Critical?

A 56-year-old male patient was referred to our practice with a history of keratoconus in the right eye. His left eye had been blind since birth due to toxoplasmosis, a congenital infection that can damage the retina and permanently impair vision. Because his right eye is his only functioning eye, every decision about his care carries extra weight. Any complication affecting his sighted eye could result in complete vision loss, so the fitting process demands an extra level of caution and thoroughness.

How Keratoconus Progression Affects Contact Lens Fit

For several years, this patient was successfully managed with corneal gas-permeable lenses, which sit directly on the cornea. However, as his keratoconus progressed, the cornea became steeper and more irregular, making a stable GP lens fit increasingly difficult.

As keratoconus advances, the cornea develops a more pronounced cone-like shape. You can think of the lens resting on the eye like a seesaw balanced on a point. As the cornea becomes more pointed, the lens loses its balance, shifting and rocking with each blink. This leads to the lens popping out more frequently, inconsistent vision, and greater discomfort throughout the day.

Two years ago, the patient was transitioned to scleral lenses. Unlike corneal GP lenses, scleral lenses vault over the entire cornea and rest on the sclera, the white part of the eye. This design bypasses the irregular corneal surface and provides a much more stable and comfortable fit. He wore his scleral lens successfully for two years.

When a Scleral Lens Stops Fitting Properly

As the patient’s keratoconus continued to advance, his existing scleral lens no longer fit as it should. The lens showed excessive bearing, meaning it was pressing too firmly against parts of the cornea rather than vaulting cleanly over it. The lens diameter was also too small for his eye. With his current lens in place, he was seeing only 20/60 with double vision, a significant decline from his previous correction.

Refitting With a Larger Scleral Lens Design

Dr. Stephanie Woo, OD, FAAO, FSLS, Dr. Nathan Schramm, OD, FSLS, FBCLA, and the specialty lens team refit the patient into an Ampleye scleral lens with 5,000 microns of sagittal depth, a significantly deeper and larger lens design suited for advanced keratoconus. The new fit showed marked improvement in corneal clearance and lens stability. With a trial over-refraction, the patient achieved 20/25 vision despite the presence of corneal scarring, a dramatic improvement over his previous 20/60 result.

What Happens After the Refit

The new lens was ordered, but the patient was counseled that additional adjustments may be needed. When a steep cornea is vaulted by a new scleral lens, the corneal shape can gradually change as it is no longer compressed by a tighter lens. As the cornea settles into its new resting shape, the prescription and fit may need to be refined over subsequent visits.

The team also discussed the possibility of a corneal transplant in the future. However, because this patient is monocular, a transplant carries significant risk. The decision was made to continue managing his vision with scleral lenses for as long as possible before considering a surgical referral.

Key Takeaways for Patients With Keratoconus

• Keratoconus is a progressive condition, and contact lens fits may need to be updated as the cornea changes shape over time
• Scleral lenses can provide stable, clear vision even for patients with advanced keratoconus and corneal scarring
• Monocular patients require extra care and conservative treatment planning to protect their remaining vision
• Regular follow-up appointments are essential to monitor fit, comfort, and vision as the condition evolves

If you or a family member has keratoconus or needs specialty contact lens care, schedule a consultation at Insight Vision Optometry, Las Vegas by calling 702-747-4070 or visiting www.insightvisionlv.com.