About Keratoconus
The cause of keratoconus is still not fully understood, but genetics and environmental factors appear to have a role. There are several factors that have been identified as potential contributors:
Risk factors for keratoconus include:
- Family history: About 10 to 20 percent of people with keratoconus have a family history.
- Excessive eye rubbing, especially during childhood: Excessive eye rubbing is thought to increase the risk of developing keratoconus by about 25 times.
- Environmental factors: Dust in the working environment and prolonged computer use after work have been identified as potential risk factors for keratoconus.
- People with allergic conditions may have increased risk of developing keratoconus. Example conditions are hay fever and asthma.
- Certain other medical conditions: People with retinitis pigmentosa, Down’s syndrome, and Marfan syndrome have increased risk.
It's important to note that while these risk factors have been identified, they may not be the sole causes of Keratoconus. The condition is likely influenced by a combination of genetic and environmental factors. If you have concerns about your risk for Keratoconus, it's best to consult with your healthcare professional.
Common symptoms of keratoconus include:
- Blurred vision: As the cornea becomes asymmetrical, it can lead to blurred vision.
- Mild to significant distortion of vision: The irregular shape of the cornea can cause mild to significant distortion of your vision.
- Rizzuti sign: A steeply curved reflection seen by shining a light on the side of your cornea closest to your temple.
- Fleischer ring: A brown ring of iron deposit around your cornea that is most visible with a cobalt blue filter.
- Vogts striae: Vertical lines observed on your cornea that usually disappear when a firm pressure is applied over your eye.
With progression or higher severity of keratoconus, symptoms may include:
- Corneal swelling
- Light sensitivity
- Halos in your vision
- Poor night vision
- Near-sightedness (difficulty seeing far away)
In rare cases, corneal blisters may develop that can cause scarring and swelling. It's important to consult with a doctor for an accurate diagnosis and appropriate treatment.
To diagnose keratoconus, the following examinations, tests, and procedures are commonly performed by a healthcare professional who specializes in medical conditions involving the eye. The examinations, test, and procedure will involve specialized ophthalmology equipemnt.
- Eye exam: The healthcare provider will look for physical signs of the condition, such as corneal thinning, Vogts striae, or a Fleischer ring.
- Eye refraction: This test measures the eyes to determine the measurement that gives you the sharpest vision.
- Slit-lamp examination: This test helps identify stromal corneal thinning, Vogts striae, or a Fleischer ring. It may also identify other problems with the surface of the eye.
- Retinoscopy: A fully dilated pupil is examined to determine signs of keratoconus.
- Videokeratography: This evaluation uses imaging systems to create a map of the cornea. This test can identify early keratoconus.
Other examinations and tests may be used depending on individual factors. Consult with your healthcare provider regarding these examinations and tests for an accurate diagnosis and assessment.
The goals of treatment for Keratoconus are to improve visual acuity and prevent the progression of the disease. Here are the different treatment options and how they work to achieve these goals:
- Eyeglasses or soft contact lenses: These are usually the first option in the early stages of keratoconus, especially for patients with high visual acuity. They help improve vision by correcting refractive errors. However, spectacles may not be effective for correcting irregular astigmatism caused by keratoconus.
- Hard contact lenses: Rigid gas permeable contact lenses (RGPCL) are often recommended for keratoconus patients who need better correction for irregular astigmatism. These lenses provide a smooth surface over the cornea, improving visual acuity by compensating for corneal irregularities.
- Corneal collagen cross-linking (CXL): CXL is a therapeutic procedure that aims to halt the progression of keratoconus. It involves applying a combination of a photo-sensitizer (Vitamin B2/ Riboflavin) and ultraviolet rays (UV) to induce photo polymerization of collagen fibers in the cornea. This increases corneal rigidity and prevents further thinning and protrusion.
- Intracorneal ring segments (ICRS): ICRS are small plastic inserts surgically placed within the cornea to reshape its curvature and improve vision. They help correct irregular astigmatism caused by keratoconus.
- Intraocular lenses (IOLs): In some cases, when contact lenses or glasses are no longer effective, IOLs may be considered as a treatment option. These lenses are surgically implanted inside the eye to correct vision. This procedure is also called a corneal transplant.
It is important to consult with an eye specialist regarding treatment options that account for individual factors and preferences..