aka Ophthalmology Befuddler 031
Your Emergency Department Director decided that a team-building exercise at the local boxing gym would be a good idea. You are left to hold the fort at work.
An hour later the Director is en route to the ED — it seems that someone has given him a good whack… Hopefully you know your stuff when it comes to blunt trauma to the eye.
Q1. What injuries may result from blunt trauma to the eye?
Following the anatomical structures of the eye from front to back, the important injuries are:
Q2. What features of history and examination need to be considered in assessing traumatic injuries to the eye?
History — in addition to the usual AMPLE history for trauma:
- Symptoms — visual disturbance or loss of vision, pain at rest or on movement, and diplopia.
- mechanism of injury — any suspicion of penetrating eye trauma requires prompt assessment, so that urgent referral can be made.
- type of projectile and velocity — small high-velocity projectiles are at higher risk of penetrating injury.
- Use of eye protection
- history of previous trauma or surgery that may compromise the structural integrity of the eye.
- Associated injuries
- Visual acuity and visual fields —
- Extraocular movements —
Try to assess this even if there is considerable eyelid edema ultrasound may help). Carefully lift the lid to ensure there is no obvious rupture.
Reduced eye movements suggests a ruptured globe, orbital wall fracture, nerve palsy or retrobulbar hematoma.
- External examination —
lid trauma, periorbital bruising and facial fractures.
- Pupils —
RAPD in some cases, e.g. retinal detachment, vitreous hemorrhage or retrobulbar hemorrhage.
- Slit lamp —
look for distortion of the anterior chamber structures or defects in the cornea or sclera. In blunt trauma rupture may occur at the limbus. Look for a hyphema. Check for lid lacerations.
- Ophthalmoscopy —
Red reflex may be absent in intraocular hemorrhage or retinal detachment. Dilate the pupil to check for retinal pathology.
- Ocular sonography
Q3. What are the appropriate investigations and management for blunt trauma to the eye?
- Consider CT or XR of the orbits if an orbital wall fracture is suspected.
- CT head/ neck if coexistent head and neck injuries need to be ruled out.
- Superficial trauma can be managed with topical antibiotics and oral analgesia
- Superficial eyelid lacerations can be sutured in the ED
- Significant injuries require specific management and ophthalmology referral (see Q4 and Q5)
Q4. What injuries resulting from eye trauma usually require immediate consultation with an ophthalmologist?
- chemical burns of the eye
- perforation of the globe or cornea
- lens dislocation
- orbital hemorrhage with increased intraocular pressure
- lacerations involving the lid margin, tarsal plate or nasolacrimal drainage system
- optic nerve injury
Q5. What traumatic eye injuries do not usually require immediate assessment by an ophthalmologist, but should be followed up within ~24 hours?
- anterior hyphema
- blow-out fracture
- retinal injuries
Q6. What should you suspect if eye pain persists following trauma despite treatment with a topical anesthetic?
A deeper injury such as traumatic iritis.
Q7. What are traumatic mydriasis and iridodialysis?
- transient traumatic mydriasis or miosis may last for days after blunt eye trauma.
- Permanent traumatic mydriasis can result from compression of the anterior chamber which forcefully dilates the pupil and results in tearing of the pupilae sphinctae muscle. As a result the pupil is dilated and exhibits neither nor consensual reactivity to light. Iris defects and a hyphema may be visible on slit lamp examination.
- There is no cure — ophthalmology follow up should be arranged.
- Intracranial injury needs to be excluded in the patient with an altered level of consciousness.
- tearing of the iris root from the ciliary body, leading to the formation of a “secondary pupil”.
- monocular diplopia may occur.
- immediate ophthalmology referral if there is decreased visual acuity or a coexistent hyphema.
- large defects can be surgically corrected
Q8. What is anterior chamber angle recession?
- Blunt injury to the ciliary body can cause posterior displacement of the iris and surrounding tissues.
- This deepens the anterior chamber, widening the anterior chamber angle, and may damage the trabecular meshwork that drains the aqueous humor.
- Severe damage can cause acute glaucoma.
Q9. What is commotio retinae?
Confluent whitening of the retina (due to edema) that may result in decreased vision as a result of a contre-coup injury to the eye. Decreased vision may occur but the the condition is generally self resolving.
Click here to see what commotio retinae looks like.
Be sure to check out Dr. Root’s amazing video talk on eye trauma.
- Ehlers JP, Shah CP, Fenton GL, and Hoskins EN. The Wills Eye Manual: Office and Emergency Room Diagnosis and Treatment of Eye Disease (5th edition). Lippincott Williams & Wilkins, 2008.
- Marx JA, Hockberger R, Walls RM. Rosen’s Emergency Medicine: Concepts and Clinical Practice, 7th edition (2009) Mosby, Inc. [mdconsult.com]
- NSW Statewide Opthalmology Service. Eye Emergency Manual — An illustrated Guide, 2007. [link to free pdf]