Keratoconus Contact Lenses Explained: Types, Fittings And Benefits

For many people with keratoconus, the moment they first wear properly fitted specialist contact lenses feels genuinely transformative. Vision that had become increasingly frustrating and blurred suddenly snaps into focus, restoring clarity they’d almost forgotten was possible. 

Unlike standard contact lenses designed for regular corneas, keratoconus contact lenses work by creating a new, smooth optical surface over your irregular cornea. This apparently simple solution requires sophisticated lens design, precise fitting and ongoing specialist care to achieve optimal results. 

At Bellamy Eyecare in Leicester and Irthlingborough, we’ve fitted specialist keratoconus lenses for more than 25 years. We’ve witnessed countless patients rediscover visual freedom they thought permanently lost – driving confidently again, returning to work they’d struggled with or simply reading comfortably for the first time in years. 

Understanding the different lens types available and how they work helps you make informed decisions about managing your keratoconus effectively. 

Why keratoconus needs specialist contact lenses 

Standard contact lenses follow your cornea’s natural shape, which works perfectly for regular corneas. However, with keratoconus, your cornea’s irregular cone shape means standard lenses either don’t fit properly or fail to correct your vision adequately. 

Specialist keratoconus lenses work differently. Rigid gas permeable (RGP) lenses maintain their shape on your eye rather than conforming to your cornea’s irregularity. The space between the lens and your cornea fills with tears, which smooth out the irregular surface. Light then focuses through the regular lens surface rather than your irregular cornea, creating clear vision. 

If your cornea is like looking through a badly warped bathroom window, the contact lens creates a perfectly flat, clear window in front of the warped one. The tears filling the gap between them complete the optical correction. 

Rigid gas permeable (RGP) lenses for keratoconus 

RGP lenses represent the traditional approach to keratoconus correction and remain highly effective for many patients, particularly those with mild to moderate corneal irregularity. 

How do RGP lenses work? 

RGP lenses are smaller than your cornea, typically around 10mm in diameter. They sit on your cornea, moving slightly with each blink. The rigid material maintains a consistent shape while allowing excellent oxygen transmission to keep your cornea healthy. 

The lens doesn’t flatten your cone – instead, it creates a new smooth optical surface with tears filling the space between lens and cornea. This tear lens becomes part of the optical system, compensating for your corneal irregularity. 

What are the benefits of RGP lenses? 

1. Excellent vision correction often surpasses what any other option can achieve for keratoconus. The rigid surface creates exceptionally sharp vision when properly fitted. 

1. Corneal health benefits from high oxygen permeability in modern RGP materials, allowing your cornea to “breathe” during lens wear. This reduces risks associated with reduced oxygen supply. 

1. Durability means RGP lenses typically last 12-18 months with proper care, making them cost-effective long-term despite higher initial investment. 

1. Adaptability allows RGP designs to be modified as your keratoconus progresses, accommodating corneal changes without necessarily requiring completely new lenses. 

What are the challenges with RGP lenses? 

As with anything, you can expect an adjustment period. Here are some of the challenges you might face with RGP lenses when getting started: 

1. Initial adaptation can be uncomfortable. RGP lenses feel more noticeable than soft lenses initially, though most people adapt within a week or two. 

1. Stability on steep corneas sometimes proves challenging. In moderate or advanced keratoconus where the cornea becomes very steep, standard RGP lenses may not centre properly or may move excessively with blinking. Specialist keratoconus RGP lenses may then become necessary. 

1. Debris sensitivity means any dust or particle getting under an RGP lens causes immediate discomfort, requiring lens removal and cleaning. 

Scleral contact lenses for keratoconus 

Scleral lenses represent a significant advancement in keratoconus management, particularly for moderate to advanced cases where RGP lenses struggle. 

How do scleral lenses work? 

Scleral lenses are considerably larger than RGP lenses, typically 14-18mm in diameter. Rather than sitting on your cornea, they vault completely over it, resting instead on the white of your eye (the sclera). 

This design creates a fluid-filled reservoir between the lens and your cornea. The lens never actually touches your cornea, which can be particularly beneficial for very irregular or sensitive corneas. 

What are the benefits of scleral lenses? 

1. Exceptional comfort often surprises people who’ve struggled with RGP lenses. Because scleral lenses don’t touch the sensitive cornea and rest on the less sensitive sclera, many wearers find them remarkably comfortable from the first day. 

1. Stable vision results from the lens’s larger diameter and scleral support. Scleral lenses move minimally with blinking, providing consistent, stable vision throughout the day. 

1. Protection and hydration come from the fluid reservoir, which continuously bathes your cornea in saline solution. This proves particularly beneficial for people with keratoconus who also have dry eyes. 

1. Success with advanced keratoconus makes scleral lenses invaluable when corneal irregularity becomes too severe for RGP lenses to fit successfully. The larger diameter and vault design accommodate even very steep or irregular corneas. 

Considerations with scleral lenses 

There are a few things you might want to consider before opting for scleral lenses: 

1. Insertion technique requires learning a specific method. Scleral lenses must be filled with preservative-free saline before insertion, which takes practice to master. However, most patients become proficient within a few days. 

1. Size and handling can feel daunting initially because scleral lenses are significantly larger than other contact lenses. However, their size actually makes them easier to handle once you’re accustomed to them. 

1. Cost implications typically make scleral lenses more expensive than RGP lenses, both initially and for replacements. However, many patients consider the improved comfort and vision well worth the investment. 

Hybrid contact lenses for keratoconus 

Hybrid lenses attempt to combine RGP lens optics with soft lens comfort by featuring a rigid centre surrounded by a soft outer skirt. 

When hybrid lenses work well 

Moderate keratoconus with relatively centered cones often responds well to hybrid lenses. The rigid centre provides clear vision while the soft skirt offers improved comfort and stability compared to RGP lenses alone. 

RGP adaptation struggles sometimes resolve with hybrid lenses for patients who cannot adapt to standard RGP lens sensation but need the optical quality rigid lenses provide. 

Limitations of hybrid lenses 

1. Fitting challenges can be significant. The lens must fit properly in both the rigid centre (for optical correction) and soft skirt (for comfortable positioning), making successful fitting more complex. 

1. Oxygen transmission to the cornea under the soft skirt is lower than with RGP or scleral lenses, potentially limiting safe wearing time. 

1. Availability and cost tend to be higher than RGP lenses and not all specialists work extensively with hybrid lenses for keratoconus. 

Other alternative keratoconus lenses 

There are several designs of specialist soft lenses available which can work well in mild keratoconus. These have the advantage of enhanced comfort although they may not provide the best possible vision. 

A further, novel, approach which can work surprisingly well is “piggy back contact lenses” where a gas permeable lens sits on top of a normal soft lens. This can give great vision and enhanced comfort and is often worth consideration. 

At Bellamy Eyecare, we assess each patient individually to determine which lens type best suits their specific corneal shape, lifestyle needs and comfort preferences. 

What is the fitting process for keratoconus contact lenses? 

Achieving excellent results with keratoconus contact lenses requires a methodical, expert-led fitting process that differs significantly from standard contact lens fitting. 

Initial assessment and measurements 

Your fitting journey begins with comprehensive measurements using advanced diagnostic technology. 

• Corneal topography creates a detailed three-dimensional map of your cornea’s surface, revealing the exact shape, size and location of your cone. This data is essential for designing lenses that will vault appropriately over irregular areas while providing stable, clear vision. 

• OCT scanning measures corneal thickness and provides detailed cross-sectional views of corneal structure. This helps identify areas of significant thinning and informs lens design decisions. 

• Refraction and vision assessment establishes your current prescription and evaluates how much improvement specialist lenses might provide compared to your glasses. 

• Lifestyle discussion explores your daily activities, occupation, hobbies and specific visual needs. Someone who spends hours at a computer may have different lens requirements than someone working outdoors or playing contact sports. 

Trial lens fitting 

Based on your measurements and needs, we select appropriate trial lenses for initial fitting. 

First lens insertion allows us to evaluate how the lens sits on your eye, whether it moves appropriately with blinking, and how it vaults over your cornea (for scleral lenses). We check for proper centration, adequate tear circulation beneath the lens and comfortable positioning. 

Vision assessment with trial lenses demonstrates the improvement specialist lenses can provide and helps determine whether additional modifications might enhance results further. 

Then there’s a comfort evaluation which ensures the lens feels tolerable and that you can realistically wear it for your required hours each day. Some initial awareness is normal but significant discomfort suggests the need for fit modifications. 

Lens customisation and refinement 

Based on trial fitting results, we order custom lenses designed specifically for your eyes. 

Bespoke lens design incorporates all the measurements and observations from your trial fitting. Each lens is manufactured to precise specifications matching your unique corneal topography. 

Your collection appointment will include thorough training on lens insertion, removal and care. For scleral lenses, this includes the proper filling technique. For RGP lenses, we cover handling these smaller lenses confidently. 

Your follow-up schedule typically includes appointments at one day, one week, one month and three months after collection. These visits assess lens performance, monitor corneal health and make any necessary adjustments. 

Ongoing care and monitoring 

Keratoconus management continues long after initial fitting because the condition can progress and lens needs may change. 

We recommend regular check-ups every six months (or more frequently if your keratoconus is progressing). These will include corneal topography to monitor any changes, assessment of lens fit and condition, evaluation of corneal health and vision checks to ensure lenses continue providing optimal correction. 

Lens replacement becomes necessary periodically. RGP and scleral lenses typically last 12-18 months, though this varies depending on lens care, deposit buildup and any prescription changes. 

What to expect: realistic outcomes 

Understanding what specialist keratoconus lenses can and cannot achieve helps set appropriate expectations. 

Vision improvement 

Most keratoconus patients achieve significantly better vision with specialist contact lenses than with glasses. Many reach 20/20 or near 20/20 vision, though this depends on several factors including severity of keratoconus, presence of corneal scarring and how well lenses can be fitted to your specific cornea. 

Some people with very advanced keratoconus or corneal scarring may achieve functional vision (good enough for daily activities and driving) without reaching perfect clarity. However, this still represents enormous improvement over uncorrected or glasses-corrected vision. 

Comfort expectations 

RGP lenses typically require one to two weeks’ adaptation. Initial awareness gradually fades as your eyes adjust. Most people forget they’re wearing lenses after the adaptation period. 

On the other hand, scleral lenses often feel comfortable immediately or within days. The larger size and scleral bearing usually mean less sensation than RGP lenses. 

Wearing time 

Most keratoconus contact lens wearers comfortably wear their lenses 12-16 hours daily. Some people manage longer wearing times, while others find their eyes prefer shorter wearing schedules. 

Building wearing time gradually during the first weeks allows your eyes to adapt while minimising discomfort. 

The Bellamy Eyecare difference 

Fitting specialist keratoconus lenses requires expertise, advanced technology, and commitment to patient care that extends well beyond the initial fitting. 

Our 45-minute eye examinations provide the time needed for thorough assessment and detailed discussion of your options. We use state-of-the-art corneal topography and OCT scanning to gather the precise measurements essential for successful lens fitting. 

With more than 25 years of experience fitting keratoconus lenses, we’ve encountered virtually every fitting challenge and developed the skills to achieve excellent results, even with complex cases. 

Perhaps most importantly, we’re with you throughout your keratoconus journey. Your lens fitting isn’t a one-off transaction – it’s the beginning of an ongoing relationship focused on maintaining your vision and eye health as your needs evolve. 

Ready to take the next step on your keratoconus journey? 

If you’re struggling with keratoconus and wondering whether specialist contact lenses could help, or if you’re currently wearing keratoconus lenses but aren’t achieving the clarity or comfort you’d hoped for, we’d welcome the opportunity to assess your situation. 

Many patients tell us they wish they’d sought specialist lens fitting sooner. The difference between managing with poor vision and experiencing clear, comfortable sight affects every aspect of daily life. 

Contact us to arrange a comprehensive keratoconus contact lens consultation at either our Leicester or Irthlingborough practice. We’ll take the time to understand your specific needs, assess your eyes thoroughly and explain exactly what we can achieve together.