LAre you having difficulties driving at night? Do you have to change your glasses lenses more often? These changes may be more than just tired eyes or nearsightedness. You might be having what we call Keratoconus (KC).
Keratoconus is a progressive eye disease characterised by the thinning of the cornea. It can be developed genetically or by environmental causes. If not diagnosed and treated correctly, keratoconus can impact the way you live your life.
So what exactly is Keratoconus? We will discuss everything you need to know about Keratoconus in this article.
What is Keratoconus?
We see through the cornea. The cornea is like a clear, dome-shaped surface at the front of the eye. It plays a vital role in allowing light to enter the eye.
However, sometimes the cornea is unable to hold its standard round shape.
The inner layer of the cornea can thin out and bulge forward, which causes the standard dome-like shape to become cone-shaped instead. This condition is called keratoconus.
The irregular shape of the cornea prevents light from accurately entering the eye, resulting in the distortion of one’s vision. Keratoconus usually affects both eyes. Most of the time, the degree of progression in each eye is unequal.
It is not a common eye condition, but it is also not rare. Keratoconus can occur in 1 of every 2000 people in Australia.
Symptoms of Keratoconus
Keratoconus is most common for people in their early teens and early 20s. Symptoms slowly aggravate over time. In most cases, it can settle by the mid-30s.
Symptoms of keratoconus include:
- Blurring and distortion of vision — Keratoconus can also cause double and ghost-like visions.
- Light and glare sensitivity — Halos and flaring forms around light sources. This makes driving at night difficult.
- Rapidly progressing nearsightedness or astigmatism — The constant need to change prescription glasses or contact lenses can also be connected to keratoconus.
- Bulging of the cornea — It may not be evident at first, but it can fully develop and become evident over time.
- Discomfort when wearing contact lenses — They may no longer feel as comfortable as they usually do.
Patients can also experience the following if they develop the disease:
- Eye strain and squinting
- Dry, irritated eyes
- Swelling of the eyes
What are the Causes of Keratoconus?
The exact origin of keratoconus remains unknown, but research suggests several possible causes such as:
Studies show that keratoconus runs in families. It is common for keratoconus to affect more than one family member.
Collagen are protein building-blocks responsible for holding the shape of the cornea. With insufficient collagen, the cornea becomes weak and unable to hold its shape.
Vigorous eye rubbing
Keratoconus is also often associated with chronic eye irritation. Constantly rubbing the eye can damage the cornea.
Deficiency in protective antioxidants
The cornea is often exposed to damaging particles like dust, exhaust from cars and pollution. Without enough antioxidants, the cornea becomes more susceptible to damage.
Other health conditions
Atopic diseases like asthma, eczema and hay fever often cause eye irritation. Patients with conditions related to collagen deficiency and connective tissue disorders like Down syndrome and Ehlers-Danlos syndrome have an increased risk of developing keratoconus as well.
Pre-existing eye diseases
Keratoconus is also often linked to other eye conditions such as eye allergies, retinitis pigmentosa, and glaucoma. Having a history of eye injury can also increase the chances of developing keratoconus.
How is Keratoconus Diagnosed?
At Ezekiel Eyes, we start with a comprehensive eye test, taking into account your medical and family history. Then we move into one or more of the following examinations
Keratometry. This test measures the curvature of the cornea. Keratometry helps in determining the shape of your cornea. However, this technique has largely been superceded.
Computerised corneal mapping. This a non-invasive test that takes a scan or photo of the cornea. It provides an accurate assessment of the corneal surface. At the end, the computer generates a map that shows the shape, thickness, and power of your cornea. It’s very important to have an accurate map of the cornea when getting contact lenses. Mapping also gives a baseline or reference so that we can monitor changes over time.
Corneal Pachymetry. It is a quick and painless test that measures the thickness of your cornea using a medical device called pachymeter.
Checking your Glasses Prescription. This examination evaluates your eyesight. Equipment like the phoropter which contains wheels of different lenses to determine your eye prescription.
Retinoscope. Other devices like the retinoscope to check for irregularities in the red-eye reflex of your eyes. You simply look at an object while your optometrist assesses your eyes with a light.
Slit-lamp examination. The slit lamp is a low-powered microscope that shines a beam of light to the eyes. It helps to get a close up look at the eyes for any abnormalities.
Diagnosing keratoconus in its early stages is crucial to help reduce changes over time. If one or both of your parents have keratoconus, if you notice any change in your eyes, or if you experience the symptoms mentioned earlier, it is highly advised to get your eyes tested.
What types of Keratoconus are there?
Keratoconus is highly individual in characteristics and severity. Here the stages and progression of keratoconus and the resulting visual performance.
1. Incipient Keratoconus Incipient keratoconus is the earliest stage of the disease. Diagnosis at this stage may be difficult and may require specialised equipment and evaluation by an ophthalmologist or an optometrist with significant experience with keratoconus patients. The quality of the vision with eyeglasses is usually adequate, although it is not as clear as prior to the development of keratoconus. Frequent prescription changes, particularly if astigmatic, may indicate that keratoconus is developing or progressing.
2. Mild Keratoconus With mild keratoconus, eyeglasses cannot provide optimal vision because the cornea has become conically deformed so that light is scattered. The patient with this condition may read the eye test chart with eyeglasses well enough to pass the driver’s test (20/40 acuity), but still may not be able to drive adequately due to distorted vision and shadows. A further complication is multiple halos and images which may surround lights sources, thereby resulting in compromised vision. Sensitivity to light of all types is also increased. These problems are worse at night. Therapeutic lenses for keratoconus are necessary to provide both clear and normal vision. A rigid therapeutic lens is usually required to provide a spherical surface over the deformed cornea.
3. Moderate Keratoconus Moderate keratoconus is a progression of mild keratoconus. While mild keratoconus can usually be corrected with a therapeutic lens so that there are no significant visual disadvantages, visual compromise may occur with moderate keratoconus, particularly at night. This is caused by the severity of the conical shape which allows rays of light to creep around the edge of the lens. This results in some glare and distortion, particularly at night when the pupil is enlarged.
4. Severe Keratoconus Vision may be significantly compromised. In those cases where it cannot be adequately corrected with therapeutic lenses, keratoplasty (corneal transplant surgery) is required. It is obviously desirable to prevent keratoconus from progressing to the severe stage.
Can Keratoconus Be Cured?
Keratoconus is a progressive eye disease. There is still no cure for keratoconus, but it can be managed and treated to lessen the symptoms and prevent it from progressing further.
Treatment varies depending on the severity of the condition. The cost of keratoconus treatment also depends on the type of treatment you are undergoing.
Does insurance cover keratoconus treatment? Depending on your Private Health Insurance policy, contact lenses may or may not be fully covered. We can claim any rebates instantly, so you don’t have to contact your Private Health Insurer.
Glasses and Contact Lenses for Keratoconus
Early in the process, keratoconus does not have much effect in your visual condition compared. Standard prescription glasses or contact lenses can improve eye problems caused by keratoconus.
Wearing proper eyeglasses can offer relatively good eyesight when keratoconus is still in its early stages. You may need to frequently change your glasses due to the continuous increase in astigmatism.
Custom soft contact lenses
Clinics and manufacturers recently introduced custom soft contact lenses designed to help with mild to moderate keratoconus. These lenses are made-to-order to fit your eyes perfectly. Aside from corrected vision, these lenses offer more comfort than the other kinds of lenses.
Gas permeable contact lenses
This type of lens is made up of oxygen-permeable polymers. Rigid lenses are often recommended because they bend perfectly over the cornea, replacing its irregular shape with a rigid refracting surface.
Hybrid contact lenses
Hybrid lenses are a combination of an oxygen-permeable lens centre and a soft lens peripheral “skirt”. This helps ensure wearer comfort as the soft lens skirt provides a good fit while the rigid centre fully covers the cornea. Hybrid lenses perfectly match the irregular shape of the cornea caused by keratoconus.
If detected in its early stages, prescription eyeglasses or contact lenses can help. But if the eye disease has already progressed significantly, your optometrist may recommend the following treatments.
Corneal collagen crosslinking
Also called as corneal crosslinking (or CXL), this procedure strengthens the ‘scaffolding’ of your cornea. CXL uses a special UV light and eye drops with riboflavin, Vitamin B. It reinforces the cornea to help slow (or stop) it from thinning.
There are two types of corneal crosslinking — epithelium-off and epithelium-on.
In epithelium-off CXL, the eye doctor removes the epithelium or the outer layer of the cornea to allow the entry of riboflavin into the cornea. Epi-off is a safe procedure. However, it can be painful and might require a few days for recovery.
The epithelium-on CXL, on the other hand, is a painless process that won’t require days for recovery. In this procedure, the doctor leaves the epithelium intact. The epi-on method requires more time for the cornea to absorb the riboflavin fully.
Intacs is a micro-thin insert that can help flatten the curve of the cornea and improve your vision. In this procedure, an ophthalmologist (or eye surgeon) surgically inserts the intacs in your cornea. The intacs can be removed or exchanged later on. This treatment can help if the keratoconus has reached the stage where it cannot be treated with contact lenses anymore.
In this surgical process, the eye doctor replaces a part or the whole affected cornea with a new, healthy cornea tissue from a donor. The operation does not guarantee a clear vision, and you may still be required to use eyeglasses or contact lens. Eye doctors strongly recommend this procedure to keratoconus patients whose condition has already reached the most severe stage.
Topography-guided conductive keratoplasty
Also known as Conductive Keratoplasty (CK), this procedure uses radio waves to reshape the cornea. It helps improve nearsightedness of patients with keratoconus. An Ophthalmologist creates a computerised topographic map of the eye’s surface to ensure the creation of an individualised treatment plan.
How Serious is Keratoconus?
Can you go blind if you have keratoconus? Keratoconus rarely leads to total blindness, but it can significantly affect how you usually live your life. Keratoconus can impair your regular daily activities or work.
Is keratoconus painful? Keratoconus can cause discomfort, especially in the advanced stages of the disease. The bulging of the cornea can cause pain in the eye. Exposure to light and straining your eyes to do even simple activities like reading or driving may also start to hurt.
Regular eye tests are important to monitor for Keratoconus. If you have a family history of keratoconus or if you’re already experiencing the symptoms, we recommend making an appointment at Ezekiel Eyes.
Tap here to Make An Appointment