What is Corneal Abrasion ?
Corneal Abrasion is superficial disruption of corneal epithelial surface, usually produced by trauma. Many corneal abrasions, are prevented due to inherent brisk protective reflexes, like closure of eyelids. Corneal abrasion is also prone to infection, like any other soft tissue injury. Corneal abrasions are more common among older children who wear contact lenses for visual improvement.
Cornea is important for normal vision. Scarring or corneal opacity may affect vision. Corneal abrasions may be prevented by wearing protective glasses, while performing activities which may put eyes at risk of injury.
Corneal Abrasion Symptoms
Symptoms of corneal abrasion include
- Pain
- Sensitivity to light (Photophobia)
- Watering
- Foreign body sensation
- Redness
- Blurring of vision
- Swelling of eyelids
Corneal Abrasion Causes
Causes include
- Trauma is a common cause, including injury by nail.
- Use of contact lenses
- Foreign body
- Chemical injury
- Thermal injury
Corneal Abrasion Diagnosis
Diagnosis depends upon clinical examination under slit- lamp. Examination may also be conducted using a portable source of ultra-violet light such as Wood’s lamp.
Small abrasions may be missed in certain cases, which require further evaluation after staining with fluorescein sodium dye. After fluorescein staining of eye, corneal abrasion appears yellow under normal light and green in cobalt blue light.
Multiple vertically arranged linear markings of abrasion on cornea may be due to retained foreign body in sulcus subtarsalis of upper eyelid. It scratches corneal surface due to unavoidable blink reflex of upper eyelid.
Corneal stromal oedema may be seen with severe or long lasting abrasions.
Differential diagnosis
Corneal abrasions may be differentiated from conditions such as
- Viral keratitis including Herpes infections.
- Foreign body in cornea
- Infective keratitis
- Conjunctival infection
- Recurrent corneal erosion syndrome in cases with multiple episodes of corneal abrasions.
- Corneal dystrophies or degenerations like epithelial basement dystrophy may produce recurrent corneal abrasions.
- Scleritis
- Acute angle closure glaucoma.
- Anterior uveitis