Cornea (start of final material)

Keratoconus Tx

• Rigid CL

• Intacs

• Corneal crosslinking

Rigid CL

Creates a regular refractive surface on top of the irregular cornea

Tears fill space between for a uniform space → Light comes to a single point and pt can see clearly

Intacs

Made of PMMA (inert material) and inserted into mid periphery of cornea outside of dilated pupil

Pulls cornea flat, not commonly used anymore

Corneal crosslinking

Prevent keratoconus progression, prevents pt from needing PK

Riboflavin applied to cornea (absorb UV) → Exposure to UV → Strengthen and improve stability of cornea

Can be performed with epi (more comfortable) or with epi removed

Pellucid marginal degeneration

Occurs in 40-50 year olds

Is an ectasia despite name, may not affect VA as much as keratoconus because protrusion is inferior cornea

Pellucid marginal degeneration clinical findings

• Concentric 1-2mm band of corneal thinning and protrusion between 4 and 8 o’clock

• Protrusion will be inferior and 1mm from limbus

• ATR astig

• “Kissing bird” or “butterfly” configuration on topography

Pellucid marginal degeneration complications

• Stromal thinning

• Hydrops, Fleischer ring, and Vogts striae are rare

Pellucid marginal degeneration Tx

• Glasses

• CL (soft, rigid, specialty)

• DALK or PK

Keratoglobus

Childhood thinning and protrusion of cornea

Keratoglobus clinical findings

• Globular cornea with thinning limbus to limbus

• Normal corneal diameter

Keratoglobus complications

• Rupture with mild trauma (ex. rubbing eyes)

• Hydrops are rare

Keratoglobus Tx

• Glasses (protection)

• Specialty CL

• Advanced Sx

Keratoconus has thinning/steepening in…

Central inferior cornea

Pellucid has thinning/steepening in…

Inferior cornea, 1mm from limbus, 4 and 8 o’clock

Keratoglobus has thinning/steepening in…

Limbus to limbus

Name diagnosis from left to right

Normal, keratoconus, Pellucid, Keratoglobus