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Basics

• Summary
• Start Here
• Symptoms
• Diagnosis and Tests
• Treatments and Therapies

Learn More

• Related Issues
• Specifics
• Genetics

See, Play and Learn

• Images

Research

• Statistics and Research
• Clinical Trials
• Journal Articles

Resources

• Reference Desk
• Find an Expert

For You

• Children
• Patient Handouts

Summary

Your cornea is the outermost layer of your eye. It is clear and shaped like a dome. The cornea helps to shield the rest of the eye from germs, dust, and other harmful matter. It also helps your eye to focus. If you wear contact lenses, they float on top of your corneas.

Problems with the cornea include:

• Refractive errors
• Allergies
• Infections
• Injuries
• Dystrophies - conditions in which parts of the cornea lose clarity due to a buildup of cloudy material

Treatments of corneal disorders include medicines, corneal transplantation, and corneal laser surgery.

NIH: National Eye Institute

Start Here

• Corneal Conditions (National Eye Institute)

Symptoms

• Eye Symptoms (American Academy of Ophthalmology) Also in Spanish

Diagnosis and Tests

• Eye Problems: Symptom Checker Flowchart (American Academy of Family Physicians) Also in Spanish
• What Are Dilating Eye Drops? (American Association for Pediatric Ophthalmology and Strabismus)

Treatments and Therapies

• Cornea Transplant (Mayo Foundation for Medical Education and Research)
• Keratoconus Treatment Options (National Keratoconus Foundation)

Related Issues

• Corneal Ulcer (Keratitis) (American Academy of Ophthalmology) Also in Spanish
• Dry Eye (National Eye Institute) Also in Spanish
• Eye Infections from Contact Lenses (American Academy of Ophthalmology) Also in Spanish
• Shingles (American Academy of Family Physicians) Also in Spanish

Specifics

• Bacterial Keratitis (American Academy of Ophthalmology) Also in Spanish
• Corneal Abrasions (American Association for Pediatric Ophthalmology and Strabismus)
• Corneal Laceration (American Academy of Ophthalmology) Also in Spanish
• Fuchs' Dystrophy (Mayo Foundation for Medical Education and Research)
• Fungal Keratitis (American Academy of Ophthalmology) Also in Spanish
• Keratoconus Frequently Asked Questions (National Keratoconus Foundation)
• Peripheral Ulcerative Keratitis (Merck & Co., Inc.) Also in Spanish
• What Is a Pinguecula and a Pterygium (Surfer's Eye)? (American Academy of Ophthalmology) Also in Spanish
• What Is Herpes Keratitis (American Academy of Ophthalmology) Also in Spanish

Genetics

• Complete LCAT deficiency: MedlinePlus Genetics (National Library of Medicine)
• Congenital stromal corneal dystrophy: MedlinePlus Genetics (National Library of Medicine)
• Fish-eye disease: MedlinePlus Genetics (National Library of Medicine)
• Fuchs endothelial dystrophy: MedlinePlus Genetics (National Library of Medicine)
• Keratitis-ichthyosis-deafness syndrome: MedlinePlus Genetics (National Library of Medicine)
• Keratoconus: MedlinePlus Genetics (National Library of Medicine)
• Lattice corneal dystrophy type I: MedlinePlus Genetics (National Library of Medicine)
• Lattice corneal dystrophy type II: MedlinePlus Genetics (National Library of Medicine)
• Meesmann corneal dystrophy: MedlinePlus Genetics (National Library of Medicine)
• Peters anomaly: MedlinePlus Genetics (National Library of Medicine)
• Peters plus syndrome: MedlinePlus Genetics (National Library of Medicine)

Images

• Corneal Abrasion (VisualDX)
• Corneal Foreign Body (VisualDX)
• Corneal transplant - series (Medical Encyclopedia) Also in Spanish

Statistics and Research

• Eye Health Data and Statistics (National Eye Institute) Also in Spanish

Clinical Trials

• ClinicalTrials.gov: Corneal Diseases (National Institutes of Health)
• ClinicalTrials.gov: Corneal Injuries (National Institutes of Health)

Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)

• Article: Induced pluripotent stem-cell-derived corneal epithelium for transplant surgery: a single-arm, open-label,...
• Article: Evaluation of Medically Reversible Limbal Stem Cell Deficiency.
• Article: Molecular and Cellular Mechanisms of the Therapeutic Effect of Mesenchymal Stem...
• Corneal Disorders -- see more articles

Reference Desk

• How the Eyes Work (National Eye Institute) Also in Spanish

Find an Expert

• American Foundation for the Blind
• American Optometric Association
• Find an Ophthalmologist (American Academy of Ophthalmology) Also in Spanish
• Finding an Eye Doctor (National Eye Institute)
• National Eye Institute

Children

• Corneal Abrasions (For Parents) (Nemours Foundation) Also in Spanish

Patient Handouts

• Cloudy cornea (Medical Encyclopedia) Also in Spanish
• Corneal injury (Medical Encyclopedia) Also in Spanish
• Corneal transplant (Medical Encyclopedia) Also in Spanish
• Corneal ulcers and infections (Medical Encyclopedia) Also in Spanish
• Fuchs dystrophy (Medical Encyclopedia) Also in Spanish
• Keratoconus (Medical Encyclopedia) Also in Spanish