Corneal ectasias are conditions characterized by a progressive thinning and protrusion of the cornea, leading to changes in its shape and, consequently, vision problems. The most well-known type of corneal ectasia is keratoconus, but there are others, such as keratoglobus and pellucid marginal degeneration.

Common Types of Corneal Ectasias:

1. Keratoconus:

   • A condition where the cornea thins and bulges into a cone shape.
   • Typically begins in adolescence or early adulthood and can progress over time.
   • Symptoms include distorted vision, increased sensitivity to light, and frequent changes in glasses prescriptions.

2. Keratoglobus:

   • A rare condition characterized by a generalized thinning of the cornea, causing it to bulge outward in a more spherical shape.
   • Can lead to significant vision impairment and is often associated with other systemic conditions.

3. Pellucid Marginal Degeneration:

   • A condition that involves a thinning of the cornea, particularly in the lower peripheral region, leading to a characteristic “butterfly” appearance.
   • Symptoms may include astigmatism and blurred vision.

Causes:

The exact causes of corneal ectasias are not fully understood, but they may include:

• Genetic predisposition
• Eye rubbing
• Allergic conditions
• Previous eye surgeries (e.g., LASIK)

Symptoms:

Common symptoms associated with corneal ectasias include:

• Blurred or distorted vision
• Increased sensitivity to light
• Frequent changes in eyewear prescriptions
• Eye discomfort or irritation

Diagnosis:

Diagnosis typically involves:

• Comprehensive eye examination, including visual acuity tests.
• Slit-lamp examination to assess the cornea.
• Corneal topography to map the cornea’s shape and identify irregularities.

Treatment:

Treatment options depend on the severity of the condition:

• Eyewear: Glasses or contact lenses (rigid gas-permeable lenses may be needed for keratoconus).
• Cross-Linking: A procedure that strengthens corneal tissue and may halt the progression of keratoconus.
• Surgery: In advanced cases, surgical options such as corneal transplantation or insertion of intracorneal ring segments may be considered.

Prognosis:

The prognosis for corneal ectasias varies. With early diagnosis and appropriate management, many individuals can maintain good vision and quality of life. Regular follow-ups with an eye care professional are crucial for monitoring progression and adjusting treatment as needed.