Scleral Lenses for High Astigmatism
What Is High Astigmatism and How Does It Affect Your Vision
Astigmatism occurs when your cornea or lens has an irregular shape, causing light to focus unevenly on your retina. High astigmatism means the degree of irregularity is significant, often around 2.5 to 3.0 diopters or higher, though definitions vary. The key distinction is whether the astigmatism is regular or irregular, as irregular astigmatism creates more complex optical distortions.
While mild astigmatism can often be corrected with standard glasses or soft contact lenses, high regular astigmatism may also respond to these options. However, irregular astigmatism and higher-order aberrations often remain uncorrected by traditional lenses.
With high astigmatism, objects at all distances may appear stretched, tilted, or doubled. You might notice that straight lines look wavy or that letters seem to blur together when you read.
- Persistent blurriness that glasses do not fully correct
- Headaches or eye strain after visual tasks
- Difficulty reading small print or seeing fine details
- Vision that changes throughout the day
Several conditions can lead to severe astigmatism. Keratoconus causes your cornea to thin and bulge into a cone shape, creating highly irregular astigmatism. Pellucid marginal degeneration affects the lower edge of your cornea, while corneal scarring from injury or infection can also distort the surface.
Post-surgical irregularities after corneal transplants or complications from refractive surgery may also result in astigmatism that standard lenses cannot correct.
Regular glasses can correct regular, symmetrical astigmatism, even at higher levels. The real limitation is irregular astigmatism and higher-order aberrations, where the cornea has an asymmetric or very steep curvature. In these cases, light passing through standard lenses still does not focus properly on your retina.
Soft contact lenses conform to the shape of your irregular cornea, which means they cannot create the smooth optical surface needed for clear vision. Even rigid gas permeable lenses may not stay centered or stable enough on a highly irregular cornea.
Before considering scleral lenses, we may explore other options depending on your specific astigmatism type and eye health:
- Toric soft contact lenses, including custom designs
- Corneal rigid gas permeable lenses
- Hybrid lenses combining rigid centers with soft skirts
- Piggyback systems pairing soft and rigid lenses
- Custom specialty soft lenses for some irregular corneas
How Scleral Lenses Correct High Astigmatism
Scleral lenses are much larger than traditional contact lenses, with diameters ranging from 14 to 24 millimeters. Their rigid gas permeable material maintains a consistent shape, unlike soft lenses that bend and flex.
This combination of size and rigidity allows scleral lenses to vault completely over your cornea without touching it, creating an entirely new optical surface.
Unlike smaller contacts that sit on your cornea, scleral lenses rest on the sclera, which is the white part of your eye. The sclera and conjunctiva can be more consistent than an irregular cornea, but often require customized landing zones that may be toric or designed for specific quadrants to achieve proper alignment.
- The lens edges sit beyond your cornea on the sclera
- The lens is designed to vault the cornea; your doctor confirms clearance after the lens settles
- The lens stays centered and stable during eye movement
When we insert a scleral lens, we fill it with preservative-free saline solution. This fluid sits between the back of the lens and your cornea, creating a tear-filled reservoir.
The reservoir fills in all the irregular bumps and valleys on your corneal surface. Light then passes through the smooth front surface of the rigid lens instead of your irregular cornea, allowing it to focus correctly on your retina.
Because scleral lenses vault over your cornea and rest on your sclera, they tend to be very stable. They are less likely to shift when you blink or move your eyes, which means your vision usually stays consistently clear throughout the day.
The rigid material may outperform other lens types in many irregular cornea cases by correcting complex astigmatism that other options cannot fully address. Many patients tell us they see better with scleral lenses than they ever have with any other form of correction.
The fluid reservoir keeps your cornea constantly bathed in moisture, which can be very soothing if you have dry eyes. Scleral lenses also shield your cornea from wind, dust, and other irritants. However, the fluid reservoir can sometimes contribute to fogging or corneal swelling in some patients, so ongoing monitoring is important.
- Reduced dryness and irritation
- Protection from environmental factors
- Less awareness of the lens during wear
- Improved comfort compared to lenses that rest on the cornea
Some scleral-specific issues to watch for and report to our office include:
- Midday fogging requiring lens removal and cleaning
- Redness after removal, known as rebound hyperemia
- Lens suction or difficulty removing the lens
- Conjunctival blanching or visible indentation from the lens edge
- Gradual reduction in comfortable wearing time over weeks or months
- New halos or blur not relieved by lens reapplication
Getting Fitted for Scleral Lenses
The scleral lens fitting process involves multiple steps to ensure the best vision and comfort:
- Initial evaluation and candidacy assessment
- Detailed corneal mapping and eye measurements
- Trying diagnostic lenses in the office
- Fine-tuning the fit and prescription
- Follow-up visits to confirm proper fit
During your first visit, we will review your vision history and examine your eyes to determine if scleral lenses are appropriate. We look at the severity and type of your astigmatism, your eye health, and your lifestyle needs.
We will also discuss what you can expect from the fitting process and address any concerns you may have about wearing large contact lenses.
While scleral lenses help many people with high astigmatism, they may not be appropriate for everyone. We assess each patient individually to determine if sclerals are the right choice.
- Very low corneal endothelial cell counts or Fuchs dystrophy without clearance from a specialist
- Severe exposure keratopathy that is not medically managed
- Uncontrolled blepharitis or meibomian gland dysfunction
- Severe allergic eye disease with excessive mucus production
- Poor manual dexterity or inability to handle and maintain the lenses
- Inability to comply with rigorous cleaning and disinfection routines
We use corneal topography to create a detailed map of your corneal surface. This technology measures thousands of points on your cornea to capture every irregularity. Some practices also use specialized instruments to measure the scleral shape and anterior segment imaging to verify vault and landing zone alignment, especially for complex irregular corneas.
- Precise measurements of corneal curvature and shape
- Assessment of the white part of your eye where the lens will rest
- Evaluation of your tear film and eye surface health
- Measurement of your pupil size and eye dimensions
We keep a set of diagnostic scleral lenses in various sizes and curves. After selecting a starting lens based on your measurements, we will teach you how we insert it and then evaluate the fit under a microscope.
We check for proper vault over your cornea, adequate edge alignment with your sclera, and comfortable lens movement. You will wear the diagnostic lens for a period so we can assess how it settles and whether any adjustments are needed.
Based on how the diagnostic lens performs, we may try different lens parameters to optimize both fit and vision. We check your vision with each lens and may perform over-refraction to determine the exact prescription needed.
The goal is a lens that vaults your cornea with adequate clearance, aligns evenly on your sclera, provides excellent vision, and feels comfortable throughout the day.
Once you receive your custom lenses, we schedule follow-up appointments to make sure they continue to fit well as you adapt to wearing them. We examine the lens position, check for any areas of pressure or gaps, and assess your eye health.
- First follow-up typically within one to two weeks
- Additional visits if adjustments are needed
- Evaluation of wearing time and comfort
The entire fitting process usually takes several weeks to a few months. Your initial evaluation and diagnostic fitting may occur in one or two visits. After we order your custom lenses, manufacturing typically takes two to four weeks.
Some patients achieve their final fit quickly, while others with very complex prescriptions may need several rounds of modifications. We remain committed to getting your lenses just right, no matter how long it takes.
Inserting, Wearing, and Removing Your Scleral Lenses
Learning to handle scleral lenses takes practice, but most patients master the routine within a few weeks:
- Preparing and filling lenses with sterile saline
- Proper insertion technique
- Safe daily wearing time
- Activities you can and cannot do while wearing lenses
- Correct removal technique
Before insertion, wash your hands thoroughly with soap and dry them with a lint-free towel. Inspect each lens to make sure it is clean and free of any cracks or damage.
Fill the bowl of the lens completely with sterile, preservative-free saline solution intended for scleral lens filling. Single-use vials are preferred by many practitioners. We recommend using a small holder or your fingertips to keep the lens steady while you fill it to the brim without air bubbles. Never fill lenses with disinfecting solution or hydrogen peroxide, as this will cause severe pain and chemical injury.
Lean forward over a mirror placed on a flat surface so the lens stays level. Hold your upper and lower lids open wide with one hand, then bring the filled lens straight onto your eye in one smooth motion.
- Look straight ahead or slightly downward
- Keep the lens completely filled to avoid trapping air
- Release your lids slowly once the lens is on your eye
- Blink gently to help the lens settle
Most patients can wear scleral lenses for 12 to 16 hours per day, though maximum comfortable wearing time varies based on your ocular surface health, corneal oxygen needs, and lens fit. When you first start, we may recommend building up your wearing time gradually to let your eyes adjust.
If you experience discomfort or vision changes before your planned removal time, take the lenses out and contact our office. Never push through significant discomfort, as this may indicate a problem with fit or eye health.
Scleral lenses are highly stable, so you can participate in most sports and physical activities while wearing them. They rarely dislodge during movement, making them ideal for active lifestyles.
You should avoid swimming or using hot tubs while wearing your lenses, as water can introduce bacteria and cause serious eye infections. For water sports, remove your lenses or wear tight-fitting goggles approved by our eye doctor. If accidental water exposure occurs, remove your lenses as soon as possible, clean and disinfect them thoroughly, and monitor for pain, redness, or light sensitivity.
Wash and dry your hands before removal. Lean forward over a towel or soft surface. Using a small plunger designed for scleral lenses, moisten the tip and press it gently slightly off-center on the lens to help break the seal, then remove the lens carefully. If the lens feels stuck, stop and contact our office rather than pulling harder.
Alternatively, you can use your fingers to gently push on the lower edge of the lens while looking up, breaking the seal and allowing the lens to tip out. Always have a clean, soft surface below to catch the lens if it drops.
Remove your lenses immediately if you notice sudden pain, redness, or vision loss. Do not attempt to reinsert your lenses. Call our office the same day for an urgent evaluation. If symptoms occur after hours or are severe, such as marked pain, rapid vision loss, or significant light sensitivity, go to urgent care or the emergency room per your local protocol.
- Sharp or stabbing pain that does not go away
- A lens that feels broken or cracked on your eye
- Sudden blurry vision that does not clear with blinking
- Any foreign object or debris trapped under the lens
- Increasing light sensitivity or photophobia
- A focal white spot visible on your cornea
- Worsening pain with each blink
- Thick mucus or pus, especially with sticky eyelids upon waking
Caring for Your Scleral Lenses
Every time you remove your lenses, rinse them with preservative-free saline and then rub each surface gently with a few drops of the approved cleaning solution. Use your fingertip to rub both the front and back surfaces for at least 20 seconds each.
Rinse the lenses thoroughly again with saline to remove all cleaning solution residue. Proper daily cleaning prevents protein and lipid deposits that can cloud your vision and irritate your eyes.
After cleaning, place each lens in a clean case filled with fresh disinfecting solution recommended by our eye doctor. Make sure the lenses are completely submerged and leave them in the solution for at least the minimum time specified by the product instructions.
- Never reuse disinfecting solution from previous days
- Replace your lens case every one to three months
- Let the empty case air dry during the day
You will need preservative-free saline for filling and rinsing your lenses, a multipurpose or peroxide-based disinfecting solution, and a daily cleaner if recommended. We may also suggest an enzyme cleaner for weekly use to remove stubborn deposits.
Other supplies include a lens case, insertion and removal plungers, and a mirror for application. Always use products specifically approved for rigid gas permeable or scleral lenses, as solutions for soft lenses may not be appropriate.
Important solution safety reminders:
- Saline does not disinfect; it is only for rinsing and filling
- Hydrogen peroxide systems must be fully neutralized before lenses go in your eye; never use unneutralized peroxide to fill lenses
- Never use tap water, homemade saline, or non-sterile liquids on lenses or cases
- Replace plungers and lens cases per our office guidance and keep plungers clean and dry between uses
With proper care, scleral lenses typically last one to three years. The exact lifespan depends on your handling habits, how well you clean them, and whether deposits build up on the lens surface.
We will monitor your lenses at each follow-up visit and let you know when it is time for replacement. Even if your lenses still look clear, they may develop microscopic changes that affect your vision or eye health.
Always handle your lenses over a soft towel or padded surface to prevent breakage if you drop them. Avoid exposing them to extreme heat or cold, and never use tap water, saliva, or unapproved solutions on your lenses.
- Keep lenses away from hair spray, perfume, and cosmetics
- Trim your fingernails to avoid scratching the lenses
- Store lenses in their case when not in use
- Check for chips or cracks before each insertion
Follow-Up Care and When to Seek Help
After your initial fitting period, we typically recommend follow-up exams every six to twelve months. These regular visits allow us to monitor your eye health, check the condition of your lenses, and make sure the fit remains optimal.
If you have an underlying eye condition like keratoconus, we may need to see you more frequently to track any changes in your corneal shape.
During your follow-up visit, we evaluate how your lenses fit using a microscope to look at the vault over your cornea and the alignment on your sclera. We check for any signs of lens deposits, scratches, or warping.
- Your corneal health and clarity
- The white part of your eye for any irritation or blood vessel changes
- Your vision quality with the current lenses
- Your comfort level and wearing time
Eye infections can develop quickly and cause permanent damage if not treated promptly. Watch for increasing redness, thick yellow or green discharge, severe pain, or rapidly worsening vision.
Other serious complications include corneal swelling from inadequate oxygen, inflammation from an immune reaction, or corneal abrasions from poor lens fit. Any of these conditions requires immediate professional attention.
Call our office right away if you experience sudden vision loss, intense eye pain that does not improve after removing your lenses, or signs of infection such as discharge, redness, or photophobia. You should also contact us urgently if your lens breaks or cracks, or if you notice new floaters, flashes of light, or a curtain over your vision.
Do not wait for your scheduled appointment if something feels seriously wrong. We would rather examine you and find nothing urgent than have you delay treatment for a condition that could threaten your sight. Remove your lenses and seek same-day evaluation when in doubt.
Your eyes can change over time due to aging, progression of conditions like keratoconus, or shifts in your prescription. If your vision becomes blurry even with your lenses in, or if your lenses suddenly feel uncomfortable, schedule an evaluation.
- Decreased wearing time before discomfort develops
- New areas of redness or irritation on your eye
- Lenses that move excessively or feel loose
- Changes in the appearance of your cornea
Frequently Asked Questions
Most patients find scleral lenses surprisingly comfortable once they get used to them. Because the lenses rest on the less sensitive white part of your eye and vault over your cornea without touching it, many people report less irritation than with smaller contacts that sit directly on the cornea.
You can wear makeup, but we recommend inserting your lenses before applying any cosmetics to avoid transferring oils or particles onto the lens surface. Choose oil-free and hypoallergenic products when possible, and always remove your lenses before taking off your makeup at night.
Contact our office as soon as possible if you lose or damage a lens. We keep your lens parameters on file and can order a replacement, though it may take several weeks to arrive. Some patients choose to order a backup pair to avoid being without correction during the replacement period.
We do not recommend sleeping in your scleral lenses unless our eye doctor has specifically approved overnight wear for your situation. Extended wear of scleral lenses is uncommon and only appropriate under explicit supervision, as sleeping in lenses increases the risk of infection and can reduce oxygen flow to your cornea, even with gas permeable materials.
Many patients achieve vision good enough to eliminate the need for glasses during lens wear. However, you will still need glasses for times when you are not wearing your contacts, such as first thing in the morning or during the evening after removal.
For many people with high or irregular astigmatism, scleral lenses provide better visual outcomes than LASIK. Refractive surgery may not be safe or effective if you have conditions like keratoconus or severe corneal irregularities. Our eye doctor can discuss which option aligns with your specific condition and the current standards of care.
Getting Help for Scleral Lenses for High Astigmatism
If you struggle with high astigmatism and have not achieved clear, comfortable vision with your current correction, scleral lenses may be the solution you need. Our eye doctor will work closely with you throughout the fitting process and provide ongoing support to ensure your lenses continue to meet your vision goals.