Keratoconus

WHAT IS KERATOCONUS?

Keratoconus is a progressive condition where the cornea becomes thinner and starts to bulge out, forming a cone shape instead of its normal round, dome shape. Keratoconus progresses over time as the cornea becomes thinner and steeper. The rate of this progression varies from person to person. It usually takes place over 10-20 years and then stops. At this point, the disease is considered stable.

WHAT ARE THE SYMPTOMS OF KERATOCONUS?

• Sensitivity to light
• Seeing halos or ‘ghosting’
• Distorted, blurry vision
• Difficulty driving at night
• Double vision in one eye or noticeably worse vision in one eye
• Eye strain, eye pain
• Headaches

CAUSES

Several factors can contribute to the development of keratoconus:

• Allergies and Eye Rubbing: Many people with keratoconus also experience allergies or other eye irritations, which often lead them to rub their eyes. Forceful eye rubbing can cause weakened corneas, worsening the condition.
• Genetics: Some individuals may inherit a genetic tendency for a weak cornea. For example, up to 30% of people with Down syndrome may develop keratoconus.
• Biology: An abnormal structure of the corneal tissue can cause it to thin.
• Hormones: Changes in hormone levels often trigger vision changes in keratoconus. These changes can occur during puberty, pregnancy, or hormone replacement therapy.
• Family History: People with close relatives, like parents or siblings, who have keratoconus are at higher risk of developing the condition.
• Ethnicity: Certain ethnic groups are at a higher risk of developing keratoconus, particularly those from countries such as India, Pakistan, Iran, Saudi Arabia, and Polynesia.

HOW DO YOU DIAGNOSE KERATOCONUS?

Several diagnostic methods are used to assess keratoconus:

• Slit Lamp Microscope: Combines an intense light source with a microscope to examine your eyes.
• Corneal Topography: Creates a 3D model of the cornea to detect any subtle changes.
• Corneal Pachymetry: Measures the thickness of the cornea.

MANAGEMENT

Various management options are available depending on the severity of keratoconus:

• Contact Lenses: When eyeglasses no longer provide clear vision, contact lenses like rigid gas permeable (GP) lenses, Kerasoft lenses, or Scleral lenses can help correct the irregular shape of the cornea.
• Corneal Crosslinking (CXL): A one-hour treatment using riboflavin (Vitamin B) eye drops combined with ultraviolet light to stop the progression of keratoconus and strengthen the cornea.
• Corneal Transplant: In severe cases, a corneal transplant may be required, where the damaged cornea is replaced with a healthy one from a donor.
• Corneal Ring Segments: Inserting clear plastic segments into the cornea to reshape it and correct refractive errors caused by keratoconus.
• Corneal Allogeneic Intrastromal Ring Segments (CAIRS): This method uses donor stroma to act as a spacer in the cornea, improving vision and topographic parameters.

SUMMARY

Keratoconus is an eye condition that progressively affects the shape and structure of the cornea. With early diagnosis and proper management, including the use of specialized contact lenses or surgical treatments, individuals can manage the condition and maintain good vision. It is important to consult with an ophthalmologist for regular monitoring and treatment options.