• Refer immediately to the emergency eye service:
• All high-velocity injuries (e.g. injuries occurring while hammering, chiselling, grinding, or lawn mowing), or an injury caused by glass, knives, thorns, darts, or pencils, should be treated as penetrating injuries until proved otherwise, as a foreign body may not be visible.
• All chemical injuries: see Managing an ocular chemical injury for emergency management while awaiting transfer to secondary care.
• If there is a foreign body that cannot be removed. Those in or near the centre of the cornea increase the risk of permanent loss of vision.
• If any of the following clinical features are present:
• Pain which is not relieved by topical local anaesthetic should be assumed to be due to something more serious than a superficial corneal injury (e.g. corneal ulceration, iritis, acute glaucoma).
• A reduction in visual acuity.
• Large abrasions (over more than 60% of the cornea).
• Corneal opacities.
• Rust rings that remain after removal of a metallic foreign body, as these may cause permanent damage.
• Hyphaema (blood in the anterior chamber of the eye), as this is associated with a risk of further haemorrhage.
• A distorted pupil, as this may be associated with a penetrating injury.
• Suspected damage to the retina.
• Deep laceration of the orbit, which may indicate intraorbital and ocular penetration, and retained foreign bodies.
• Subconjunctival haemorrhage, if it tracks posteriorly and there is a history consistent with a possible orbital fracture.
• Marginal lacerations, as the lacrimal ducts may be damaged.
• Also urgently refer people with:
• Persistent symptoms after 72 hours.
• Worsening symptoms.
• A corneal abrasion which shows no improvement (healing) on a daily basis.
• Recurrent abrasions may be referred non-urgently. These usually occur at night when there is little secretion of tears and the epithelium may be torn off.

• Recurrent abrasions: treatment is long term, and a surgical procedure (e.g. epithelial debridement, or corneal stroma puncture) may be needed [Khaw et al, 2004a].

These recommendations are based on published expert opinion [Eagling and Roper-Hall, 1986; McGuinness, 1998; Shields, 2000a; Shields, 2000b; Khaw et al, 2004a; Wilson and Last, 2004].