Key points

• Children are particularly vulnerable to ocular trauma.
• Serious eye injuries can be under appreciated in the child who has a painful eye, blurred vision or extensive subconjunctival haemorrhage.
• Ensure prompt and adequate analgesia.
• If a ruptured globe is suspected or identified: stop examination, place an eye shield over the eye to avoid extrusion of ocular contents, obtain a CT Orbit (if there is a history of a possible foreign body), keep nil by mouth and refer urgently to ophthalmology.
  
  

Introduction

Paediatric ocular trauma is a cause of significant morbidity, with up to 280,000 hospital admissions worldwide per year. ^[1] However, hospital admissions only account for around 5% of total eye injuries – so it has been estimated that worldwide there are around 6 million episodes of eye injury in children.^[2] Open globe injury (ruptured globe due to blunt trauma, or laceration due to a penetrating injury) is a severe form, which, in children, is most commonly caused secondary to penetration with a sharp object whilst at home.^[3]

Children account for between 20 and 59% of all eye injuries^[4].  They are more predisposed to eye injury due to their developing physical coordination, limited ability to detect environmental risks and a more vulnerable facial morphology.^[5]  The outcome of paediatric eye injuries is worse than that of adults due to their visual immaturity, increased years of visual loss and potential for amblyopia.^[5] Most paediatric eye injuries (66.2%) occur during play – predominantly whilst at home under supervision of parents / caregivers (47.7%), but often whilst at school / nursery (24.4%).^[2]  Sharp instruments are the most common cause of injury, followed by plants, animals, toys or sports equipment.^[2]  In the Australian context, it has been estimated that sports-related eye injuries make up 11% of all paediatric eye injuries. ^[6] Boys are twice as likely to sustain a significant eye injury compared to girls.^[2]

Features of ocular trauma history and examination (see also RCH Clinical Practice Guideline: Acute eye injuries in children and RCH Clinical Practice Guideline: Penetrating eye injury)

Serious eye injuries can be under-appreciated when children present with a painful, blurred vision or an extensive subconjunctival haemorrhage.  In all traumatic eye injuries consider the following principles: ^[7]

1. Manage (other) life threatening injuries
2. Ensure the structural integrity of the globe
3. Assess vision in the injured AND the uninjured eye
4. Seek ophthalmology consultation where required

Where an open globe injury is suspected it is important to minimise child distress – as crying can raise ocular pressure leading to extrusion of intraocular contents.

The key diagnoses to seek and identify are:

• Open globe injury – ruptured globe or penetrating laceration
• Foreign body – corneal or intra-ocular
• Large hyphaema
• Retinal detachment
• Corneal burns – chemical or thermal

History

Symptoms

• Pain – at rest or with movement
• Vision - loss (ongoing or temporary, global or central) or blurring or other disturbances such as flashes (associated with retinal detachment) or floaters (associated with intra-ocular injury)
• Foreign body sensation – pain with blinking or moving eye
• Discharge from the eye
• Photophobia

Mechanism of Injury 

• Risk of high velocity penetrating injury – small projectiles at high velocity have a higher risk of penetration - eg playing with air-rifle, near lawn-mowers, using metal grinders or other power tools, hammering
• Risk of low velocity penetrating injury – eg running with sharp object, catching eye on sharp thorn or plant material
• Risk of blunt injury  -eg sports injury such as squash ball to orbit, motor vehicle accident (be aware an airbag ocular injury to a front seat passenger can be a combination of a blunt or penetrating injury with a chemical burn)
• Risk of chemical or burn injury to eye – eg flash burn to face, playing with detergent pods.  Alkali burns are generally more dangerous causing liquefactive necrosis.

Other

• Any first aid already provided?
• Glasses or eye protection worn?
• Presentation maybe delayed so ask for history over the previous few weeks.
• History of previous trauma to eye(s).
• Associated trauma/injuries.

Examination

If adequate examination is not possible due to either the child’s age or level of cooperation, specialist assistance should be sought.  Where there is significant concern for an open globe injury, it is prudent not to overly distress the child through multiple attempts at examination, as crying can lead to an increase in intraocular pressure, with the resultant extrusion of intraocular contents.  Early referral to ophthalmology is appropriate in these cases – along with administration of appropriate systemic and topical analgesia and anti-emetics.  Ondansetron is an appropriate option, as it has a lower risk of causing a dystonic reaction.  Opiate analgesia may lead to nausea and vomiting which can increase intra-ocular pressure – so consider pre-treating with anti-emetics if you think strong analgesia is required.

Even when open globe injury is not suspected, appropriate analgesia, oral or intranasal analgesia as well as topical (single drop of preservative free local anaesthetic – eg amethocaine 1%) should be given to reduce pain and aid the child’s ability to tolerate examination.  However, it is worth noting that local anaesthetic is itself a direct epithelial toxin, so it shouldn’t be used repeatedly (and patients should not be discharged with topical local anaesthetic).  A child life specialist (play therapist) may also assist in helping the child relax during an examination.  Be aware that when a child has suffered a monocular injury, occluding the good eye may increase their distress (as they will no longer be able to see).

Where a burn is suspected, first aid should take precedence over a complete examination.  This consists of copious irrigation (after local anaesthetic and systemic analgesia given).  In some cases the patient may need to be sedated to facilitate first aid treatment.

A complete examination of the eyes requires examination of:

1.Visual acuity in both the injured and uninjured eye

• Use age appropriate charts and the patients normal corrective lenses or pinhole
  •  Snellen chart from school age
  • “E” chart from about 3 years old
  • Kay picture book – ages 2-3

A difference of more than 2 lines on an eye chart is likely to be significant.  If unable to read a chart, check the patient can count fingers or confirm light perception

2.Eye movement

• Check the child can look in all directions
• Check for diplopia or pain with eye movement
  • In trauma, an orbital floor fracture can lead to reduced upward gaze (entrapment of inferior rectus)

3.Visual fields

• Four quadrant testing in older children
• Traumatic visual field loss is usually grows, however, subtle changes may occasionally occur with retinal detachment and intra-ocular foreign bodies

4.Pupils

• Check size, symmetry, shape and reactivity
• Look for both a direct and indirect pupillary response
  • A relative afferent pupillary defect may suggest an increase in retrobulbar pressure (ie a retrobulbar haemorrhage secondary to trauma), optic neuropathy or severe retinal detachment.

5.Lids, conjunctiva and sclera

• Look for swelling, chemosis, ptosis, ecchymosis and lacerations
• Evert the lids to look for foreign bodies on the underside
• If there is a laceration on the eyelid – check to see if it extends through the tarsal plate – maintain a high level of suspicion for globe rupture in the presence of any eyelid laceration
• Look for a subconjunctival haemorrhage – whilst many are benign, a localised haemorrhage may suggest penetrating injury. An inability to visualise the posterior extent of a subconjunctival haemorrhage may suggest an orbital or base of skull fracture.  In infants, subconjunctival haemorrhage may be a sign of non-accidental injury.^[8]

6.Cornea, Anterior Chamber and Iris

• Look for a hyphaema – this is blood in the anterior chamber – mild cases may only have suspended red blood cells seen in the anterior chamber. 
• Check there is no iridodialysis – a disinsertion of the iris from the sclera
• Look for corneal abrasions and foreign bodies
  • Application of fluroscein dye will help identify abrasions
  • Vertical scratches on the cornea indicate the likely presence of a foreign body under the upper eyelid

7.Fundus

• Look for red reflex, assess the optic disc, the macula and periphery
• A red reflex may be diminished due to vitreous haemorrhage or lens opacity
• Retinal detachment may be seen as a grey flap
• Check for retinal haemorrhages and papilloedema

8.Palpate the orbital rim

• Assess for bony fractures
• Check for paraesthesia in the infra-orbital nerve distribution

9.Consider assessing intraocular pressure

• In the context of trauma, and intraocular pressure of <10 will indicate a potential globe injury

Fig 1: External anatomy of the eye

Ocular Trauma

Blunt

• Intraocular contents are at risk of considerable damage by blunt force trauma.
• Orbital bony wall is relatively thin thus susceptible to fracture from transfer of mechanical energy across globe.
• Potential Injuries:
  • Lid injury
  • Orbital blow-out fracture
  • Retrobulbar haemorrhage
  • Hyphaema - this refers to blood in the anterior chamber and is secondary to a tear in the iris and / or ciliary body. (see Fig 2.)
  • Traumatic mydriasis – associated with iris sphincter tears.
  • Iridodialysis - this is the detachment of the iris root from its insertion site at the ciliary body.  It can lead to a "D-shaped" pupil.
  • Lens dislocation
  • Cataract
  • Vitreous Haemorrhage
  • Retinal detachment
  • Traumatic Iritis - or inflammation of the anterior chamber post blunt trauma is common in children.  Examination reveals anterior chamber cell and flare, there may also be a poorly reactive pupil, with sustained miosis.
  • Ruptured Globe – (see below).

• Consider CT Orbit +/- brain when concerned about blowout fracture or head injury.
• Immediate Ophthalmology consultation is indicated in:
  • Actual Globe or corneal perforation
  • Concern of globe rupture
  • Orbital haemorrhage
  • Lens dislocation
  • Visual changes
  • Lid laceration 

Fig 2: Hyphaema after blunt trauma

Open globe injury

Open globe injury refers to a full-thickness mechanical injury to the cornea and/or sclera.  The two broad types are^[3]:

1. Ruptures – which result from blunt trauma such as a ball striking the orbit and
2. Lacerations – which are caused by a sharp object entering the globe.  Lacerations are further classified as:
   • Penetrating injuries – where there is a single wound to the globe - for example from point of knife
   • Perforating injuries – where there are separate entrance and exit wounds
   • Intra-ocular foreign body – where there is an entrance wound with a foreign body within the globe – for example from a metal splinter in a grinding injury

Penetrating injuries are the most common, followed by intraocular foreign body injuries, then rupture, with perforating injuries being the least common.  The most common location for injury is at home – especially for pre-school children. Older children are increasingly likely to sustain an open globe injury outside of the home.[9]  A common cause of injury is kitchen items, followed by sticks, pencils, metallic and elastic objects.  Older children may suffer projectile injuries through hammering or the use of paintball guns / air rifles.

If penetrating eye injury is suspected:

• Do NOT force the eyelid open as pressure on the lids may cause extrusion of ocular contents.
• Do NOT attempt to remove a protruding foreign body from the globe. 

Symptoms

• Pain
• Decreased visual acuity

Signs

Anterior signs:  peaked or irregular pupil, iris prolapse, corneal laceration, hyphaema, extensive subconjunctival haemorrhage and chemosis (conjunctival swelling).

Posterior signs: poor red reflex (vitreous haemorrhage), decreased vision, uveal prolapse, 

Treatment

• Keep patient fasted in anticipation of theatre.
• Adequate analgesia with antiemetics as vomiting may increase intra-ocular pressure.
• Sit patient upright where able (may depend on ability to clear C-spine)
• Shield the eye, be careful when shielding not to press on the eye.
• Do Not instil drops or ointments into eye.
• Prompt discussion with ophthalmologist
• CT scan of orbit to investigate for ocular foreign body.
• Commence ciprofloxacin and check tetanus status.

Fig 3. Corneal laceration with prolapse of iris following penetrating trauma

Orbital blow out fracture

These occur following high energy blunt traumas (e.g. hit with ball, bat or fist) that create an increase in intra-orbital pressure.

Symptoms

These include pain and diplopia (especially on vertical movement), tenderness, eyelid swelling. Nausea +/- vomiting and pain on eye movement may occur if there is entrapped muscle.

Signs

Ptosis, tenderness, restricted eye movements (especially on vertical movement), crepitus of lower lid.  The globe may appear "enopthlamic"  (recessed into the orbit) or displaced downwards.  There may also have associated  ocular injuries secondary to blunt trauma – (see above). Infraorbital nerve involvement leads to reduced sensation to cheek, upper teeth and gums of affected side. 

Fig 4: A 4yo child with right orbital 'blow out' fracture associated with entrapment

Management

• CT scan with coronal cuts is the investigation of choice to assess the integrity of bony orbit.
• Refer to Ophthalmology and Plastic Surgery units.

Fig 5: Isolated right orbital floor fracture

Non accidental injury (NAI)

Non-accidental causes are a common and significant cause of ocular trauma in paediatrics.

Red Flags 

• Unexplained periorbital haemorrhage, especially in setting of other injuries.
• Poorly or unexplained mechanism of injury.
• Any burns in a small child.

Detailed fundoscopy by an ophthalmologist is required in all cases of suspected NAI, and should be considered in all cases of head injury of infants and young children.

Key pathological findings include: Extensive multilayered (retinal, pre-retinal and subretinal) haemorrhages in all four quadrants with possible vitreous haemorrhage 

Fig 6: Retinal haemorrhages following non-accidental injury

Chemical burns

Acid and alkaline solutions that come into contact with the eye surface can cause considerable damage and are a true ophthalmic emergency.  Immediate irrigation prior to arrival in ED is ideal, if this hasn’t occurred it should be performed on arrival to ED

To facilitate irrigate of the eye:

• Instil local anaesthetic drops to affected eye(s)
• Irrigate with normal saline -  minimum one litre, aim to include under eyelids and conjunctival fornices.
• If possible use a Morgan Lens otherwise continue irrigation using a gloved hand to retract lids as possible.
• Review patient’s pain regularly, re-instil local anaesthetic drops 10 minutely as required.
• After one litre of irrigation, review the eye.  Wait 5 minutes after ceasing irrigation to check eye pH using universal indicator paper, aim for pH equal to unaffected eye or if both eyes are effected then aim for pH close to neutral; discuss with specialist and continue irrigating if outside this range.
• Severe burns will usually require a minimum of 30 minutes of irrigation.

All chemical burns should be assessed by ophthalmology after wash-out.

Alkaline burns are especially damaging as the base solution will denature proteins, lyse cell membranes which enhances penetration into the eye and increases further damage.

Acid solutions also cause severe damage, however acid solutions largely precipitate proteins which can limit the area and depth of necrosis.

Corneal abrasions and foreign bodies

One of the most common paediatric ocular presentations to emergency:

• Present with (often sudden onset) painful and watering red eye.
• Use slit lamp, if available and child can tolerate, or ophthalmoscope for examination.
• Examine both pre and post instillation of 2% fluorescein drops to identify foreign body and potential corneal abrasion by the child inadvertently rubbing their eyes.
• Always evert lids if possible. Most subtarsal foreign bodies will be close to the eyelid margin.

Precautions

• Attempt to remove the foreign body  as retained matter can cause issues: infections if organic, rust rings if metallic.
• Upon successful removal of foreign body and in setting of corneal abrasion, discharge with topical antibiotic drops (e.g. chlorsig) and consider antibiotics ointment nocte as lubricating effects are soothing and can help with sleeping.

To remove the foreign body

• Instil topical anaesthetic drop (e.g. tetracaine hydrochloride 0.5%); warn the patient the drop will sting briefly.
• Attempt to remove foreign body with a moistened cotton bud.
• If unsuccessful and if child is able to tolerate sitting still at a slit-lamp, use a 25 gauge needle with bevel up to remove corneal foreign bodies.
• If still unsuccessful after 2 attempts, cease and contact Ophthalmology.

Fig 7:  Corneal foreign body - metal fragment with rust ring

Fig 8: Linear corneal abrasions suggestive of a subtarsal foreign body

Lid lacerations

An eyelid laceration should be treated as a potential penetrating injury until proven otherwise.  Superficial laceration away from the lid margin, may be safely closed by standard suture techniques.  However any laceration that involves the eyelid margin should be repaired by an ophthalmologist given the complex lid anatomy (tarsus, grey line, medial and lateral longitudinal tendons and canaliculus).

Lacerations, even minor, to the medial canthus may involve the canaliculus and thus should be referred. 

Treatment

• Control the bleeding with elevation of head and direct pressure. Avoid pressure to the globe.
• Examine eye for penetrating injury once lid-bleeding is controlled.
• Suspect canalicular injury, if the medial part of either the upper or lower eyelid is involved. In this situation, early involvement of the Ophthalmology Unit is required.

References:

1. Abott J, Shah P.  The epidemiology and etiology of pediatric ocular trauma.  Surv Ophthalmol.  2013; 58(5):476-485
2. Sii, F et al. The UK Paediatric Ocular Trauma Study 2 (POTS2): demographics and mechanisms of injuries. Clinical Ophthalmology 2018:12:105-111
3. Xintong, L. et al.  Pediatric open globe injury: A review of the literature. K Emerg Trauma Shock 2015;8(4):216-223
4. MacEwen, CJ. Et al.  Eye injuries in children: the current picture.  Br J Ophthalmol. 1999;83:933-936
5. Hoskin, AK. Et al.  Eye Injury Prevention for the Pediatric Population. Asia-Pacific J Ophthalmol 2016 5(3):202-211
6. Hoskin AK et al.  Sports-related eye and adnexal injuries in the Western Australian paediatric population Acta Opthalmologica 2016;94:e407-e410
7. Root, JM et al.  Nonpenetrating Eye Injuries in Children. Clinical Pediatric Emergency Medicine 2017;18(1):74-86
8. DeRidder, CA et al.  Subconjunctival Hemorrhages in Infants and Children: A sign of nonaccidental Trauma. Ped Emerg Care 2013;29(2):222-226
9. Gunes et al.  Characteristics of Open Globe Injuries in Preschool children Paediatric Emergency Care 2015;31(10): 701-703