Our eyes are constantly changing.
The eye has special muscles that are always adjusting to changes in our environment, protecting our ability to see, and working hard to ensure we can see clearly. However, there are many conditions that can impact our vision.
Keratoconus is a less common condition, but can have a serious impact on a person’s vision.
What Is Keratoconus?
Keratoconus is an eye condition that results in an irregularly shaped cornea.
Typically, the cornea (clear front surface of the eye) is a round, dome shaped surface. Imagine your eyeball as a basketball. No matter how you turn it, the curve and shape should remain the same.
Patients who have keratoconus have a thin, misshapen cornea. Often, their cornea becomes more cone-shaped. The irregular shape prevents the proper focusing of light once it enters the eye, causing vision issues.
To diagnose keratoconus, your optometrist will review your medical history and complete a comprehensive eye exam. This usually includes:
- Corneal topography: digital imaging used to map the cornea’s curvature
- Slit-lamp exam: corneal exam to check for abnormalities
- Pachymetry: measurement of the thinnest parts of the cornea
Keratoconus affects approximately 1 in every 2,000 people and usually first presents during puberty. This condition can continue to progress until a person is in their mid-30s, or longer, depending on the person.
As keratoconus progresses, the cornea bulges out further (creating that cone shape) and causing more vision issues.
In rare cases, the cornea can swell and cause significant vision impairment. This swelling occurs when the strain of the corneal bulging creates small cracks along the back surface. These cracks can take weeks or months to heal, but your optometrist can prescribe eye drops to help you recover.
While there is no known way to prevent keratoconus, several treatments are available to help people with this condition see clearly and comfortably.
Symptoms & Causes
The symptoms of keratoconus can change or worsen with time as the condition progresses. Generally, the early stages of keratoconus are characterized by slight blurring or distortion in a person’s vision and frequent changes to glasses prescription- like every few months.
With time, more symptoms can develop, such as:
- Light sensitivity
- Poor night vision
- Eye irritation/fatigue
- Frequent headaches
- Worsening/clouding of vision
- Seeing glare/halos around lights
While keratoconus is a less common eye condition, it can become a more serious issue if left untreated. The exact causes of keratoconus aren’t certain, but research shows that significant factors could include:
- Eye rubbing
- Chronic inflammation
In the United States, 1 in 10 patients with keratoconus has a close relative with the disorder, too. Additionally, a history of asthma, allergies, Ehlos Danlers syndrome, Down’s syndrome, or retinitis pigmentosa can put a person at risk for developing keratoconus.
Treatments for keratoconus depend on a patient’s age and the severity of the condition.
In the early stages, keratoconus can be treated with prescription eyewear. This is typically when a patient is in their teens or early 20s. This treatment is the same solution used for patients with myopia (nearsightedness) and astigmatism.
With more severe keratoconus, an optometrist may recommend hard contact lenses. At 2020 Eyecare Ohio, we offer scleral lenses as a keratoconus treatment option. These specialty lenses help by significantly improving the vision.
When glasses are no longer sufficient in correcting vision problems caused by keratoconus, your optometrist may recommend corneal collagen cross-linking.
This procedure is performed by an ophthalmologist, usually in an out-patient setting. The doctor applies a vitamin B solution to the eye which is activated by ultraviolet light for approximately 30 minutes. This promotes collagen bonds to form in the cornea, creating a stronger surface.
This treatment may only be a temporary fix, but can preserve the cornea’s shape and improve vision.
In the advanced stages of keratoconus, your optometrist may recommend surgical treatments.
A corneal ring is an implantable, plastic, C-shaped ring used to flatten the cornea. This helps a patient see more clearly and protects the cornea from further bulging or damage. Additionally, a corneal ring can make wearing contact lenses much easier.
Alternatively, your doctor may recommend a corneal transplant. This requires a donor cornea to replace the existing corneas. Typically, corneal transplants are performed as outpatient procedures.
These options are more intensive but ideally, provide long-lasting results.
How Is Keratoconus Different from Astigmatism?
Keratoconus and astigmatism are both conditions that affect the cornea.
Astigmatism is a common eye condition that causes the cornea (or lens) to have mismatched curves. With astigmatism, the cornea or lens has more of an egg-like shape which prevents light entering the eye from focusing correctly. Astigmatism has a perpendicular shape which makes correcting it easier with glasses/traditional soft contact lenses.
In both cases, the condition can worsen over time. The key differences between keratoconus and astigmatism are the frequency that these appear in patients, the orientation of the astigmatism (keratoconus is irregularly shaped because of the cone), and the associated symptoms and risks.
Typically, astigmatisms are treated with prescription eyewear. Keratoconus can be treated with eyewear in the early stages, but due to the irregular shape of the cornea, it often requires more intensive treatment down the road.
It’s unlikely a person will develop keratoconus if they have no family history of the condition, whereas astigmatism can occur in anyone. It’s also far more common and less impactful to a person’s vision.
When To Visit Your Optometrist
If you experience vision impairments or have questions regarding your ocular health, don’t hesitate to contact our team! We’re here to help.