- Symptoms: usually asymptomatic
- May occur as an idiopathic condition in elderly as a lucid area separating corneal arcus from the limbus.
- Epithelium is intact
- No vascularization
- Corneal thinning may occur
- May be associated with systemic diseases such as rheumatoid arthritis, systemic lupus erythematosus, polyarteritis nodosa or other collagen vascular diseases.
- No treatment is required in idiopathic degenerations.
- Treatment of systemic diseases.