An injury to the eye or its surrounding tissues is the most
common cause for attendance at an eye hospital emergency
department.
History
The history of how the injury was sustained is crucial, as it gives
clues as to what to look for during the examination.
If there is
a history of any high velocity injury (particularly a hammer and
chisel injury) or if glass was involved in the injury, then a
penetrating injury must be strongly suspected and excluded.
If there has been a forceful blunt injury (such as a punch),
signs of a “blowout” fracture should be sought.
The
circumstances of the injury must be elicited and carefully
recorded, as these may have important medicolegal
implications.
It may not be possible to get an accurate and
reliable history from children if an injury is not witnessed by an
adult.
Such injuries should be treated with a high index of
suspicion, as a penetrating eye injury may be present. Examination
A good examination is vital if there is a history of eye injury.
Specific signs must be looked for or they will be missed.
It is
vital to test the visual acuity, both to establish a baseline value
and to alert the examiner to the possibility of further problems.
However, an acuity of 6/6 does not necessarily exclude serious
problems even a penetrating injury.
The visual acuity may also
have considerable medicolegal implications.
Local anaesthetic
may need to be used to obtain a good view, and fluorescein
must be used to ensure no abrasions are missed.
Corneal abrasions
Corneal abrasions are the most common result of blunt injury.
They may follow injuries with foreign bodies, fingernails, or
twigs.
Abrasions will be missed if fluorescein is not instilled.
The aims of treatment are to ensure healing of the defect,
prevent infection, and relieve pain.
Small abrasions can be treated with chloramphenicol
ointment twice a day or eye drops four times a day until the eye
has healed and symptoms are gone.
Ointment blurs the vision
more but provides longer lasting lubrication compared with eye
drops.
This will help prevent infection, lubricate the eye
surface, and reduce discomfort.
For larger or more uncomfortable abrasions a double eye pad
can be used with chloramphenicol ointment for a day or so until
symptoms improve.
If the eye becomes uncomfortable with the
pad, it can be removed and the eye treated as per a small
abrasion.
The pad must be firm enough to keep the eyelid shut.
Ointment or drops can then continue.
If there is significant pain
cycloplegic eye drops (cyclopentolate 1% or homatropine 2%)
may help, although this will further blur the vision.
Oral analgesia
such as paracetamol or stronger non-steroidal anti-inflammatory
drugs can also be used.
Patients should be told to seek futher
ophthalmological help if the eye continues to be painful, vision is
blurred, or the eye develops a purulent discharge.
Recurrent
abrasions Occasionally the corneal epithelium
may repeatedly break down where there has been a previous
injury or there is an inherently weak adhesion between
the epithelial cells and the basement membrane.
These
recurrences usually occur at night when there is little secretion of tears and the epithelium may be torn off.
Treatment is long
term and entails drops during the day and ointment at night to
lubricate the eye.
Occasionally, a surgical procedure (such as
epithelial debridement or corneal stromal puncture) may be
carried out to enhance the adhesion between the epithelium
and the underlying basement membrane.
Foreign bodies
It is important to identify and remove conjunctival and corneal
foreign bodies. A patient may not recall a foreign body having
entered the eye, so it is essential to be on the lookout for a
foreign body if a patient has an uncomfortable red eye.
It may
be necessary to use local anaesthetic both to examine the eye
and to remove the foreign body.
Although patients often
request them, local anaesthetics should never be given to
patients to use themselves, because they impede healing and
further injury may occur to an anaesthetised eye.
Small loose conjunctival foreign bodies can be removed
with the edge of a tissue or a cotton wool bud or they can be
washed out with water.
The upper lid must be everted to
exclude a subtarsal foreign body, particularly if there are
corneal scratches or a continuing feeling that a foreign body is
present.
However, this should not be done if a penetrating
injury is suspected.
Corneal foreign bodies are often more
difficult to remove if they are metallic, because they are often
“rusted on.”
They must be removed as they will prevent healing
and rust may permanently stain the cornea.
A cotton wool bud
or the edge of a piece of cardboard can be used.
If this does
not work, a needle tip (or special rotary drill) can be used, but
great care must be taken when using these as the eye may easily
be damaged.
If there is any doubt, these patients should be
referred to an ophthalmologist. When the foreign body has
been removed any remaining epithelial defect can be treated as
an abrasion.
Radiation damage
The most common form of radiation damage occurs when
welding has been carried out without adequate shielding of the
eye.
The corneal epithelium is damaged by the ultraviolet rays
and the patient typically presents with painful, weeping eyes
some hours after welding. (This condition is commonly known
as “arc eye.”)
Radiation damage can also occur after exposure to large
amounts of reflected sunlight (for example, “snow blindness”)
or after ultraviolet light exposure in tanning machines.
Treatment is as for a corneal abrasion.
Chemical damage
All chemical eye injuries are potentially blinding injuries.
If chemicals are splashed into the eye, the eye and the
conjunctival sacs (fornices) should be washed out immediately
with copious amounts of water.
Acute management should
consist of the three “Is”: Irrigate, Irrigate, Irrigate. Alkalis are particularly damaging, and any loose bits such as lime should
be removed from the conjunctival sac, with the aid of local anaesthetic if necessary.
The patient should then be referred
immediately to an ophthalmic department.
If there is any
doubt, irrigation should be continued for as long as possible
with several litres of fluid.
Blunt injuries
If a large object (such as a football) hits the eye most of the
impact is usually taken by the orbital margin.
If a smaller object
(such as a squash ball) hits the area the eye itself may take most
of the impact.
Haemorrhage may occur and a collection of blood may be
plainly visible in the anterior chamber of the eye (hyphaema).
Patients who sustain such injuries need to be reviewed at an eye
unit as the pressure in the eye may rise, and further
haemorrhages may require surgical intervention.
Haemorrhage
may also occur into the vitreous or in the retina, and this may
be accompanied by a retinal detachment.
All patients with
visual impairment after blunt injury should be seen in an
ophthalmic department.
The iris may also be damaged and the pupil may react
poorly to light.
This is particularly important in a patient with
an associated head injury, as this may be interpreted as (or
mask) the dilated pupil that is suggestive of an acute extradural
haematoma.
The lens may be damaged or dislocated and a
cataract may develop.
Damage to the drainage angle of the eye
(which cannot be seen without a mirror contact lens and a slit
lamp microscope) increases the chances of glaucoma
developing in later life.
If the force of impact is transmitted to the orbit, an orbital
fracture may occur (usually in the floor, which is thin and has
little support).
Clues to the presence of an inferior “blowout”
fracture include diplopia, a recessed eye, defective eye
movements (especially vertical), an ipsilateral nose bleed, and
diminished sensation over the distribution of the infraorbital
nerve.
These patients need to be seen in an ophthalmic
department for assessment and treatment of eye damage, and a
maxillofacial department for repair of the orbital floor.
Penetrating injuries and eyelid
lacerations
Lacerations of the eyelids need specialist attention if:
● the lid margins have been torn these must be sewn together
accurately
● the lacrimal ducts have been damaged the laceration may
involve the medial ends of the eyelids and it is likely that the
lacrimal canaliculi will have been damaged, and these may
need to be reapposed under the operating microscope
● there is any suspicion of a foreign body or penetrating eyelid injury objects may easily penetrate the orbit and even the cranial
cavity through the orbit.
Penetrating injuries of the eye can be missed because
they may seal themselves, and the signs of abnormality are
subtle.
Any history of a high velocity injury (particularly a
hammer and chisel injury) should lead one strongly to suspect
a penetrating injury.
In that case, the eye should be examined
very gently and no pressure should be brought to bear on the
globe.
It is possible to cause prolapse of intraocular contents
and irreversible damage if the eye and orbit are not examined
with great care.
Signs to look for include a distorted pupil, cataract,
prolapsed black uveal tissue on the ocular surface, and vitreous
haemorrhage.
The pupil should be dilated (if there is no head
injury) and a thorough search made for an intraocular foreign
body.
If there is a suspicion of an intraocular or orbital foreign
body then orbital x ray photographs, with the eye in up and
down gaze, should be taken.
If the eye is clearly perforated it should be protected from
any pressure by placing a shield over the eye, and the patient
should be sent immediately to the nearest eye department.
Sympathetic ophthalmia, in which chronic inflammation
develops in the normal fellow eye, is a potentially serious
complication of any severe penetrating eye injury.
The risk of
this increases if a penetrating eye injury is left untreated. All
penetrating eye injuries should receive immediate specialist
ophthalmic management without delay.
