If you have been informed that you cannot wear regular contact lenses because of an irregular cornea or some ocular surface disease like dry eyes or Keratoconus, you may consider asking your eye doctor about scleral contact lenses. Scleral lenses are a specialized type of contact lenses designed to address these specific conditions. Another option for those with Keratoconus is Rose K Lenses.
Scleral lenses stand out due to their unique design and composition. These lenses have a larger diameter compared to traditional contact lenses, and they are made of gas-permeable, rigid material. What sets them apart is their ability to fit over the entire cornea and rest on the white part of the eye known as the sclera. This placement on the sclera allows scleral lenses to effectively manage corneal irregularities such as Keratoconus and ocular surface abnormalities.
One of the key functions of scleral lenses is acting as a fluid reservoir. This reservoir provides a continuous source of moisture to the cornea, making them an excellent choice for individuals with severe dry eyes. Many individuals with dry eyes find it challenging to tolerate regular soft lenses, but scleral lenses offer comfort and relief.
Moreover, scleral lenses play a critical role in enhancing overall visual acuity. By replacing the irregular cornea with a perfectly smooth optical surface, these lenses improve the quality of vision for individuals with conditions like Keratoconus. They are highly oxygen-permeable, making them suitable for even severely affected corneas.
Scleral contact lenses are noticeably larger than standard gas permeable contacts, with the smallest available diameter being approximately 14.5 mm, and the largest can be up to 25 mm. The size of the lens used is often chosen based on the complexity of the condition.
According to their size and the area of eye where the lenses rest on, there are 3 types of Scleral lenses:
During your scleral lens fitting consultation, your optometrist will determine the best scleral lens type and size using various diagnostic lenses tailored to your specific condition, needs, and parameters.
Scleral Lenses are also prescribed for corneal conditions such as irregular astigmatism, irregular cornea, post-corneal transplant vision correction, post-corneal grafts, corneal abrasions, dry eye disease, and more. All of these conditions can lead to reduced or poor vision, significantly impacting one's quality of life. Large-diameter gas permeable contact lenses, also known as specialty lenses, are used to address these corneal diseases.
Optometrists and ophthalmologists recommend scleral contact lenses for a variety of challenging eye conditions, with one of the most common being keratoconus.
Keratoconus is classified into three stages: Mild, Moderate, and Severe Keratoconus. When it reaches an advanced stage where scleral lenses become necessary, it is known as Advanced Keratoconus. At this point, a complete custom lens design is required.
In cases of early keratoconus, where the eye's power is not very high, a standard gas permeable lens can be considered. However, sometimes these lenses do not center properly on the eye or move excessively with blinks, causing discomfort. Switching to a large-diameter scleral contact lens can often solve these problems and provide stable vision.
Scleral lenses are designed to vault the corneal surface, creating corneal and limbal clearance while resting directly on the sclera. This unique design often makes them more comfortable for individuals with keratoconus.
Scleral contact lenses are an excellent option for eyes that have undergone a cornea transplant. Individuals with severe dry eyes, who may require a large tear reservoir, are often fitted with larger scleral lenses because they can hold more fluid and adapt to significant changes in corneal curvature. Severe dry eyes can result from conditions such as Sjogren’s syndrome, graft-versus-host disease (GVHD), and Stevens-Johnson syndrome.
Scleral lenses not only provide sharper vision but also offer comfortable and improved vision quality throughout the day when worn.
Scleral lenses are a type of specialty contact lenses that are custom-made to the exact specifications prescribed by your optometrist after they perform all the tests and fitting, to provide the best possible vision, eye health, and comfort. Also, there is a wide range of scleral lens designs and contact lens materials available which your eye specialist can offer you according to your ocular health and requirements. Most patients get comfortable with scleral contact lenses within the first week of wear.
The cost of scleral lenses can be higher as compared to regular and other keratoconus contact
lenses and can range from Rs 75000 for both eyes to Rs 200000 for both eyes. This is because the fitting fees associated with scleral lens fitting and lens replacement costs are higher than other contact lenses and vary with different brands.
Generally, the process of acquiring a scleral contact lens is as follows:
Step 1: Visit the eye hospital for a comprehensive eye test; testing your eye number, general eye health, reviewing the diagnosis and retinal evaluation. In case you are diagnosed with keratoconus, your eye doctor might ask you to undergo a topography test where we come to know, how severe is the keratoconus and the reports also help
we decide on the scleral contact lens parameters to consider for your eyes.
Step 2: Before the scleral contact lenses are given, there is a scleral contact lens fitting process, where a trial scleral lens is fitted on the eye to understand how it behaves in your eye and note down some crucial measurements. Usually, the trial visit is for 1-2 hours because scleral contact lens fitting is different from other keratoconus lenses.
Step 3: Once the trial is finalized, we send the lens parameters along with the power of the lens to the lab for the lenses to be made and after a few weeks the lenses arrive. This is when you will be called up for the “Dispensing visit”. The newly arrived lenses are fitted on your eye and verified if the lenses are made as per the eye doctor’s instructions. On this visit, you will be taught the insertion and removal techniques of the scleral contact lenses and also counseled and trained regarding the care and maintenance procedures.
Step 4: Follow-up visits: Since scleral contact lenses require this rigor to finalize the fit,
the process of wearing and maintaining them is quite overwhelming sometimes, thus, a
follow up after 7 days of wear, 2 weeks after wear, a month after wear and every 6
months thereafter are required to make sure the lenses and your eyes are doing fine.
| Parameters | Scleral Contact Lenses | Soft Contact Lenses |
|---|---|---|
| Comfort | As scleral lenses vault over the cornea and do not touch the cornea, scleral lenses provide excellent wearing comfort during lens wearing hours. | Soft contact lenses offer excellent wearing comfort. However, occasional end-of-the-day discomfort may occur due to dryness of the eye in some patients. |
| Vision Quality | The quality of vision is excellent with scleral lenses, even in cases where vision is not 100% with regular lenses or spectacles, as long as the cornea is clear and free of opacities. | Soft Contact Lenses offer exceptional vision quality when the cornea is not irregular in shape. |
| Fitting Process | A specialized fitting trial, which can take 2-3 hours, is necessary for scleral lenses. To achieve excellent results, it is essential to consult a specialist optometrist trained in fitting and assessing specialty contact lenses. | While not strictly requiring a specialist for fitting, it is recommended to consult a qualified eye care professional. |
| Cost | Due to the extensive customizations required, the cost of each scleral lens per eye can range from INR 45,000 to 50,000. | Soft contact lenses are more affordable, and high-quality lenses do not cost more than INR 4,000 per eye. |
| Care and Maintenance | Scleral lenses are cleaned and stored in a separate multipurpose disinfectant solution. Due to their rigid nature, they are susceptible to scratches. Therefore, the lenses must be handled with care. Additionally, use a clear saline solution that is preservative-free to avoid any toxic effects on the eye. Be sure to follow your optometrist's instructions. | Daily disposable variants require no lens storage and should be discarded after a day's wear. In contrast, fortnightly and monthly disposable lenses should only be reused for 15 days and 30 days, respectively. These lenses should be cleaned and stored in the prescribed multipurpose disinfectant solution exclusively. |
Scleral contact lenses are prescribed in cases where we don't want the cornea to be touched by the lens. Thus, the biggest advantage of scleral lenses is its clearance over the entire cornea. Furthermore, in cases of dry eyes, there is a constant need to instill eye drops and thus there can be compliance issues, as patients may forget to instill a few times. Scleral lenses offer an added benefit of constant saline reservoir between the lens and the cornea, hence, scleral lenses are also used in dry eye treatment. Another advantage of scleral lens is its longevity, i.e, provided the parameters of the eye, such as power, curvature of the lens, disease and the lenses are taken care of as advised, scleral lens can be used for 5-6 years without any difficulties.
Contact lenses have been successfully used for decades. They have even been shown to reduce the need for transplant surgery in people who suffer from significant keratoconus.
One of the biggest drawbacks of scleral contact lenses can be their cost. These lenses are custom fitted, which means that it takes a trained professional, or eye care practitioner more time and effort to get them right. Each lens is individually crafted, which can drive up the cost. In the long run, however, scleral lenses are generally not drastically more expensive than other specialty contact lenses.
Complications are relatively rare. Possible hazards of sclera lens wear can include:
Most of the potential dangers of scleral contact lens use are related to user error or a poor lens fit.
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