Scleral Lenses
Scleral lenses are categorized into three generations, differing in fit and vision but similarly resting on the least-sensitive portion of the eye, the sclera. Made from advanced oxygen-permeable materials, they ensure optimal oxygen supply to the cornea. Their rigid structure allows for customization to vault over the eye and gently land on the sclera, resulting in greater comfort compared to other contact lens options.
Scleral lenses offer greater comfort than soft contact lenses, as they don’t rely on tears for hydration. You fill them with saline before you insert them, so they act as a moisture chamber for the cornea!
Lastly, vision with generation two/three scleral lenses generally exceeds any other contact, non-contact, or surgical option due to the customized shape/optics of the lens.
First Generation Scleral Lenses - “Scleral Lens 1.0”
The first generation of scleral lenses solved many issues that were troubling to spectacle, soft contact, and gas permeable wearers.
Positives of a first generation lens
Positives:
- Providing a new standard for vision for those with very irregular corneas. Scleral lenses removed much (but not all) of the distortion that was still noticeable through spectacles, soft contacts, and gas permeable lenses.
- Rotational stability was no longer a problem due to the size/stability of a larger lens.
- Comfort from initial wear due to the size of the lens.
- First generation scleral lenses also greatly benefit practitioners who prefer to fit scleral lenses occasionally, as the fitting sets are generally low-cost and additional scleral lens equipment is unnecessary.
Drawbacks of a first generation lens
Drawbacks:
- The main drawbacks of the first generation are the lack of customization of the fit and the inability to fine-tune your vision to the degree capable with the second or third generation.
- The base lens shape generally starts off as a perfectly spherical lens and modifications are then made after the fact through visual estimation (although some practitioners utilize instrumentation to assist with visual estimation). The eye is not perfectly spherical, it is generally curved in a different manner in all 360 degrees. First generation scleral lenses, at their most advanced, only offer four regions which are customizable.
- One analogy for a first generation scleral lens is that of an off-the-rack suit. You select the nearest size and from there limited elements can be shortened or tapered, but you do not ever have the option to extend or to completely break down and rebuild the suit to best fit your body. The cornea is extremely sensitive to improperly-fitting lenses and so first generation lenses can fall short.
- Common complaints for new patients who are still wearing first-generation scleral lenses involve lens discomfort, redness, foggy vision, or hazing, which can all be caused by an improperly fitting lens.
- Visually, first generation scleral lenses provide clear vision to the wearer relative to traditional correction, as was first described in the windshield analogy in the previous sections.
Second Generation Scleral Lenses - “Scleral Lens 2.0”
First-generation scleral lenses lack customizability, leaving some patients with discomfort, haze, fogging, and glare despite their overall satisfaction. Recognizing the need for improvement, the eyecare industry has introduced second-generation scleral lenses aimed at addressing these fitting issues.
These new lenses are akin to custom-tailored suits, requiring precise measurements. To achieve the complete shape of the eye, two tools are essential: a corneal topographer for the cornea’s shape and a scleral topographer for the sclera’s surface. Properly fitting scleral lenses on the irregular scleral surface is crucial for eye health. Scleral topographers are specifically designed for this purpose, which is why they’re not used by practitioners who fit scleral lenses infrequently. Lumen Optometric is proud to be the first in Los Angeles County to implement this advanced technology.
Positives of a second generation lens
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These lenses fit better, which results in a healthier lens-to-eye relationship. The Pentacam AXL Wave utilizes a rotating Scheimpflug camera to capture over 1 million data points from fifty different perspectives, creating a complete 3D model of the eye. The lens is then matched to the 3D model of your eye.
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Due to the better fit, there is a significant reduction in foggy vision, discomfort, and debris within the lens.
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Allows for additional fine-tuning of the distortion on the front side of the cornea, resulting in slightly sharper vision relative to the first generation for highly irregular corneas.
Drawbacks of a second generation lens
- Still cannot correct for the distortion that originates from the back side of the cornea. Despite patients being able to see smaller letters on the exam chart, smearing/glare/distortion (especially at night) can still result depending on the severity of one’s keratoconus.
Featured second-generation scleral - Valley Contax PosEYEdon scleral lens
The PosEYEdon lens is the latest scleral lens adapted for patients with healthy eyes who are looking for sharper vision, greater comfort, and longer wear time.
The PosEYEdon has been instrumental in tackling tricky visual problems such as high levels of nearsightedness, farsightedness, or astigmatism.
You'll spend more time doing what you love and less time thinking about your vision. Things like driving, camping, reading, hiking.
The PosEYEdon lens works as a moisture chamber to reduce dryness amongst our dry eye patients.
Curious? At the consultation, you can experience vision and comfort through the PosEYEdon lens.
Third Generation Scleral Lenses - “Scleral Lens 3.0”
This section can be a little more complicated, so bear with us! The cornea has two surfaces: the front surface, which is exposed to the environment, and the back surface, which is inside your eye. Each surface has its own irregularity/distortion. Generation 3 scleral lenses were created to reduce the distortion caused by the interaction of these two surfaces.
We are proud to be the first office in Los Angeles County to offer the third generation of scleral lenses. The instrument that makes this possible is the Ovitz Xwave Aberrometer, released in 2021. This instrument is the first to allow us to integrate all of our scleral technology vertically. This vertical integration means that we can combine 3D modeling of the eye with a model of the front and backside corneal distortion to create a lens that not only fits well but also reduces glare/distortion/smearing in one’s vision.
As your doctors, we first design a fully-customized second-generation scleral lens. We fine-tune the fit and vision to reach your eye’s maximum potential. If you still present distortion from the back surface of the cornea, we then utilize the Xwave to quantify the distortion. We then collaborate with optical engineers from Ovitz to combine our fit with their fine-tuned visual enhancements to elevate your second-generation scleral to a third-generation scleral. Your team at that point consists of your doctors and a team of optical engineers!
Positives of a third generation lens
- Significant reduction of glare, smearing, distortion to one’s vision
- Improvement in overall clarity not possible with generations one or two
Drawbacks of a third generation lens
- Requires much more time to finalize a scleral fitting due to the integration of information between two teams. Second generation scleral fits typically require three revisions to finality and introducing third generation changes adds on another two-to-three revisions. Ultimately, we are very picky when it comes to vision for our patients and most patients are willing to work with us to achieve their visual goals.
- Not all patients benefit from third generation scleral lenses. Some patients are fortunate to not have corneal backside distortion, so they aren’t in need of this technology. Other patients may also present with very opaque corneal scarring, which unfortunately we cannot solve with back surface correction. For those looking for the highest achievable level of clarity, despite having keratoconus or no corneal problems, the third generation provides the clearest outcomes.
Not sure if you're a candidate?
There are other conditions where scleral lenses can help from both a visual and comfort perspective.
- Patients with a history of corneal surgery, trauma, or complications from routine surgery may have irregular corneal surfaces which preclude them from wearing glasses, soft contacts, or gas permeable lenses. One common corneal surgery that can lead to an irregular corneal surface is Radial Keratotomy (RK).
- Ocular surface disease from systemic conditions such as Sjogren’s syndrome, Graft-versus-host disease, or Steven-Johnson’s syndrome benefit greatly from the liquid barrier from a scleral lens.
- Dry eye disease patients also benefit from the scleral lens liquid barrier. Sclerals are less dry than soft contacts because unlike soft contacts, sclerals don’t require your tears to self-hydrate the plastic.
- Patients who are now in their forties or fifties and can no longer read comfortably with their soft or gas permeable lenses may benefit from the reading enhancements offered by scleral lenses.
- This is not a condition, but patients who require high-level, visual performance. Competitive athletes who need stable, clear, and reliable vision are also great candidates for scleral lenses.
Allow us to take part in your vision care and you’ll love what you see.