WHAT ARE SCAN-DESIGNED SCLERAL LENSES ?
Scan-designed scleral lenses are lens made completely based on unique scans of your cornea (front clear part of the eye) and sclera (white portion of the eye).
These lenses are unique because unlike conventional scleral lenses, they are not limited to the "curve" design structure. Conventional scleral lenses look at lenses on the eye and the Doctor makes adjustments to the curves of the lens to ensure the lens fits around the eye properly, and provides good vision.
But our eye structure is very unique and can have many "lumps and bumps". Some people have more abnormalities than others. The scanning software lens creates maps of your eye and designs the scleral lenses to fit around these lumps and bumps for a better fit that is achieved faster than the trial and error of conventional lenses.
This is a cornea-scleral scan (using our Pentacam CSP software) of a patient of ours who had a very irregular sclera, as well as a cornea with radial keratotomy scars.
The colors on this map show the differences in elevation on their eye. This patient was fit with a scleral lens and achieved 20/20 vision.
This is a look at the scleral lens design software. This patient had two large elevations on the white portion of their eye (sclera). Conventional lenses would be more difficult to fit. They elected to order a scan-designed lens for a better fit which results in more comfort.
The yellow is the scleral lens. You can see at the bottom where the edge of the lens lifts up to flow seamlessly around that elevation.
WHAT ARE SCLERAL LENSES ?
Scleral lenses are a unique type of lens made of an oxygen-permeable rigid plastic that is filled with a sterile saline solution before being placed on the eye.
"Contact lens" is not-applicable to this type of lens because there is no contact with the lens and the cornea (clear front of the eye). This type of lens lands on the white portion of the eye, the sclera.
The space between the cornea and the lens is filled with saline, providing moisture to the cornea all day long, and has the ability to mask corneal irregularities, abnormal conditions, and highly diseased eyes.
This lens essentially creates a new, more perfect, front surface of the eye. This allows for much sharper vision for those with keratoconus, corneal transplants, radial keratotomy, corneal scarring, post-LASIK ectasia, and even severe dry eye.
HOW LONG DO SCLERAL LENSES LAST?
Scleral lenses can last for as long as: your corneal shape doesn't change, your prescription doesn't change, and the material remains unscratched. These lenses are very high quality and an excellent investment in clear, comfortable vision.
Unless there is a change, we usually recommend getting a new pair every two years as well as having backup pair, especially if you have an ocular condition and rely on these lenses to see.
WHO CAN BENEFIT FROM SCLERAL LENSES?
1.) Dry Eyes
When traditional treatments have failed, scleral lenses can be an amazing management option for severe dry eye. There is a reservoir of preservative-free sterile saline in between your cornea and the lens which stays in place all day. This provides constant lubrication to the eye.
In cases like Stevens-Johnson syndrome or Sjogren's Syndrome, where more than just the cornea is compromised, the lens can be made to be much larger to protect the conjunctiva (white portion of the eye) as well.
These lenses, in combination with excellent dry eye management can provide wonderful relief to patients who have been suffering from severe dry eye.
Keratoconus is a condition where the cornea thins and bulges forward. When an eye with keratoconus sees an image, the irregular cornea bends the light rays so they are unable to reach the retina in a straight line, making images distorted and blurry. For this reason, glasses are ineffective because once the light rays go through the glasses, they still are obscured by the cornea.
Scleral lenses are a great option to restore vision to people with keratoconus. Between the keratoconic cornea and the scleral lens, the liquid "fills in" the irregular surface to create a "new" corneal surface, where light can pass through clearly to the retina. For very advanced keratoconus, sometimes other contact lenses are difficult to fit without worrying about scarring the cornea. The scleral lens takes away this fear and allows the cornea to remain untouched.
3.) Corneal transplants
Corneal transplantation is a great way to restore vision to those who have extremely abnormal or scarred corneas. However, corneal transplants do introduce some irregularity to the corneal surface that may result in vision that cannot be corrected to 20/20 with glasses.
Between the irregular cornea and the scleral lens, the liquid "fills in" the irregular surface to create a "new" corneal surface, where light can pass through clearly to the retina. This allows the eye to see once again.
4.) Radial keratotomy
Scleral lenses can be transformative for those who have had radial keratotomy (RK) surgery. Out of all lens options, this is the ideal lens for RK patients because the liquid layer between the lens and the eye minimizes a lot of the daily visual fluctuations that these patients experience. It can also improve vision immensely by minimizing irregularities caused by the incisions on the corneal surface.
CAN SCLERAL LENSES CORRECT MY PRESCRIPTION?
Yes! Along with helping people achieve dry eye relief and correcting irregularities, we can correct your full prescription with the lens.
Scleral lenses can correct your glasses prescription, your astigmatism, and if you are over 40 years old and need reading glasses, your near prescription as well.
If you are over 40 years old, you have the options below with scleral lenses:
1.) Distance Scleral Lenses + Reading Glasses: Both eyes corrected for distance with the lenses. For reading, you may wear progressive glasses (for a full range of vision) or reading glasses (for one range of vision) over the scleral lenses when needed.
2.) Monovision: One eye corrected for distance vision and the other eye corrected for reading or computer. The brain uses each eye independently and chooses which one to use for which task. Most people can adapt to this, some people cannot.
3.) Multifocal scleral lenses: This is a different design of scleral lens which combines both distance vision and near vision into the same lens. This requires a different fitting procedure but can give incredible vision. Multifocal lenses do require some compromise since the lenses are accomplishing so many tasks. Nighttime vision may give slightly more halos around lights due to the design of the lens. Most people can adapt to this over time.
Q: WHAT IS THE FITTING PROCESS LIKE?
A: The fitting process starts with a Specialty Contact Lens Consultation. This consultation covers all testing necessary to determine the best option to perfect your vision. You may try on different types of lenses at this examination as well to assess your visual potential.
If you decide to proceed with contact lenses, the lenses are ordered for you and you will return in about 1-3 weeks to try on the initial lens. This initial lens is our first chance to see how things look. If the lenses looks good you will leave with the lenses and return for a follow up visit to give us feedback on comfort and vision. We may need to alter the lens at this visit and will order lenses with different parameters.
For specialty contact lenses, once we start the fitting process you are able to return for unlimited follow ups and lens changes for three months until we have a final product.
Q: LEARN ABOUT SCLERAL LENSES FROM DR. MORRISON
Learn about scleral lenses and whether they will benefit you with Dr. Caitlin Morrison and Dr. Stephanie Woo. This is a recording of a live webinar Dr. Morrison and Dr. Woo did specifically for patients! Real patients also ask questions at the end of the webinar.