Download Emergency Eye Care - Med Student Workshops

Emergency Eye Care
Kevin P. Kilgore, MD
History & Examination
Patients will generally present with complaints of abnormal visual acuity, eye pain or
discomfort, change in appearance of lids, orbit or eye, diplopia or discharge.
ƒ A purulent discharge is most commonly secondary to a bacterial infection and needs
antibiotic treatment.
ƒ If the discharge is watery (epiphora) and not associated with pain or redness, it is usually
due to excessive formation of tears or obstruction of the lacrimal drainage system.
ƒ If the discharge is watery and associated with photophobia or burning, suspect a viral
conjunctivitis or keratoconjunctivitis
Associated Signs and Symptoms
In reviewing pain the examiner needs to consider location, character, alleviating and exacerbating
factors and associated symptoms.
ƒ Blurred vision more serious if doesn't improve with blinking (which renews the tear layer).
ƒ Deep throbbing, or with eye movement more significant than scratching.
ƒ Acute localized pain worsened by movement of the eye or lid is suggestive of a foreign
body or corneal abrasion.
ƒ Itching sensation is usually associated with allergic reactions.
ƒ Photophobia - primarily associated with iritis or keratitis
ƒ Binocular diplopia - usually associated strabismus, diplopia si due to corner or lens
abnormalities
ƒ Flashing lights / curtains - associated with retinal detachment
ƒ Blackout or grayout - usually vascular in origin (i.e. artery occlusion)
General medical / surgical history: The history is very important and should include:
ƒ Previous symptoms similar to current complaints
ƒ Previous eye diseases (i.e., cataracts, glaucoma, injury, glasses / contacts)
ƒ Previous history of ocular surgeries; may easily explain anisocoria
ƒ History of trauma/injury and details
ƒ Allergies
ƒ Medications (digitalis intoxication classically presents as yellow-green halo effect about
objects)
ƒ Tetanus status
ƒ Occupation (arc welder, sheet metal worker, chemist)
ƒ Past medical history – diseases such as diabetes mellitus, hypertension, atherosclerotic
disease, hyperthyroidism and connective tissue disorders commonly present with ocular
manifestations
Basic Examination
The ocular examination should be done in a directed and systematic manner as with any other
organ system. The ophthalmology exam should include the patient's history, physical examination
of the eyes and assessment of visual function.
• Visual Acuity - All patients with ocular complaints should have their visual acuity
determined. Visual acuity determination should not delay more important procedures
such as irrigation. The best “corrected” acuity should be determined. Patients should be
examined using their glasses or contact lenses if possible. Pinhole testing may be
performed if necessary to correct for refractive errors. Patients must be coached to do
their best using the standard Snellen chart for far-vision testing. If the patient is unable to
read the chart at all, visual acuity may be graded as to whether the patient can count
fingers, discern hand motion, perceive light with or without projection, or the patient may
experience no light perception at all:
i. FC - finger counting (distance)
ii. HM - hand motions (distance)
iii. LP - light perception
iv. NLP - no light perception
• External Examination - Begin this examination by moving steadily toward the patient while
inspecting and palpating the bony orbits. Next look for signs of obvious globe
abnormalities such as asymmetry, perforation, proptosis or enophthalmos. Observe the
lids and conjunctivae by inspecting fornices and inverting the lids as needed. Inspect the
canthal structures.
• Pupillary Reactions - The pupils must be examined for shape, size, and reactivity. The
pupil should be round. The most common cause of an irregularly shaped pupil is prior
surgery. Other etiologies include globe penetration and synechiae or scarring from
previous intraocular inflammation. Direct and consensual pupillary responses should be
elicited. An afferent pupillary defect (Marcus-Gunn pupil) may only be apparent with a
“swinging light” examination where the penlight is alternately swung from eye to eye
watching for symmetry of pupillary movements. A positive swinging light test is present
when one pupil constricts or dilates more sluggishly with direct light than with indirect
stimulation (while shining a light in the opposite pupil). This finding may be the only clue
to a retinal detachment, papilledema, optic nerve contusion optic neuritis, posterior pole
hemorrhage, HTN retinopathy
• Ocular Motility - A patient should be able to move both eyes through all fields of gaze.
Impaired ocular motility may be the result of orbital muscle entrapment (e.g., orbital
fracture), direct muscle injury, orbital infection, or a central nervous system lesion.
Diplopia may be the result of corneal and lens irregularities or extraocular muscle
dysfunction. If the diplopia is monocular (diplopia persists after covering one eye) the
problem is likely the lens or cornea of the affected eye. If the diplopia disappears when
either eye is covered the problem is related to dysfunction of an extraocular muscle.
• Visual Field Testing - If a visual field defect is suspected, mapping of the defect may assist
in diagnosis. Confrontational visual field testing is easily performed by the emergency
physician while facing the patient with eyes at the same level. The patient covers one eye
and the patient covers the opposite eye while the examiner uses his fingers at the
periphery of vision to directly compare the patient’s peripheral vision with his assuming
that if the patient is unable to see the finger there is a field defect.
• Direct Ophthalmoscopy - examining the optic disc and retina with the direct
ophthalmoscope completes the routine ophthalmologic examination. Diagnostic mydriasis
(dilating the pupil) is indicated when funduscopic examination is necessary but
compromised by miosis or cataract. Patients with narrow anterior chambers are at risk
for acute glaucoma and should not be dilated.
Materials needed for examination
ƒ
ƒ
ƒ
ƒ
ƒ
Eye charts
Blank/pinhole eye occluder
Eye pads/shield
Lid elevator (Desmarres retractor)
Spud / burr
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
Fluorescein strips
U-V light
Light and magnifying sources
Schiøtz or Tono-Pen
Slit lamp
Imaging - radiography and tomography, ultra-sound, CT scanning.
Triage of Eye Conditions
The patients presenting complaint should dictate triage.
Emergent triage criteria
• contact with caustic substances
• loss of visual perception
• progressive loss of vision
• abnormal globe shape or position
• cloudiness of the cornea or anterior chamber
Urgent triage criteria
• significant pain
• lacrimation, pruritus without visual changes
True Ocular Emergencies
Chemical burns
Alkali burn (liquefactive necrosis) - more frequent
and are generally more severe than acid burns.
These solutions destroy the cell structure not only of
the epithelium but also of the stroma and
endothelium. While acids create an initial burn and
then cease, alkalis may continue to penetrate the
cornea long after the initial trauma. Common sources
of alkalis include ammonia, lye and lime.
Acid burn (coagulative necrosis) - Acids tend to
bind with tissue proteins and coagulate the surface
epithelium. This barrier of coagulated material abates
further penetration so acid burns are typically
confined to superficial tissues. Acid burns of the eye
result from exploding car batteries, which contain
sulfuric acid.
A chemical burn requires immediate care. Literally every second counts. The most
important consideration in chemical burns is immediate copious irrigation. This single measure
offers the best chance of reducing the ultimate physical damage to the eye. Test the eye with
litmus paper to establish the residual pH. Check the lids and fornices and remove any particulate
matter (more common with drain cleaners, cement, etc.). Ophthalmologic consultation is
necessary as soon as the immediate condition is stabilized.
Globe rupture
Intraocular pressure measurement should be
avoided in any cases suspected to be full
thickness.
• Visual acuity must be taken, if possible.
• No unnecessary manipulation of the eye
• No pressure patch
• Remove contact lens.
• An eye shield, to protect the eye, should be
applied.
• Request Ophthalmologic consultation.
• Maintain patient NPO.
• Tetanus status
As part of the protective reflex, the eye rotates upwards as it closes (Bell’s phenomenon).
Penetrating injuries are often situated inferiorly in the sclera. The vast majority of such scleral and
cornea-scleral wounds involve underlying structures. Scleral lacerations or ruptures require
primary closure as soon after the injury as possible, in order to restore normal anatomical
relationships and reform the collapsed eye without incarceration of uveal tract or vitreous in the
wound.
Corneal laceration
The patient with a corneal laceration has experienced significant ocular trauma, typically from a
metallic object such as a hand tool. Pain is intense. Patients are photophobic and lacrimate
profusely. There is a significant attendant uveitis and the anterior chamber is shallow or even flat
in a full thickness laceration. Bubbles within the anterior chamber are a key finding. There is
significantly reduced visual acuity. Other associated findings may include lens dislocation,
iridodialysis, and hyphema.
Damage to the iris may result in an irregularly
shaped, unreactive pupil. Additional pressure on
the globe may result in extrusion of uveal tissue
through the wound.
• Visual acuity must be taken, if possible.
• Judicious use of fresh topical anesthetic will help
relieve the patient's discomfort and allow
evaluation.
• No unnecessary manipulation of the eye
• No pressure patch
• An eye shield, to protect the eye, should be
applied.
• Request Ophthalmologic consultation.
• Maintain patient NPO.
Seidel Test - A partial thickness laceration must be
differentiated from a full thickness laceration with
the use of Seidel’s test. As fluorescein is added,
you will see the aqueous "flowing like a river in a
sea of fluorescein." With a corneal laceration, the
patient frequently is lacrimating too heavily for the
Seidel test to be performed with any degree of
accuracy.
Remember: Be wary of a linear corneal
"abrasion".
Intraocular foreign body
Missile injuries of the eye are not uncommon.
These injuries usually present with a history of
having been hammering (metal on metal), drilling
or sawing. A high index of suspicion for intraocular
foreign body must be maintain when this history is
given. Patients may state a sudden impact
sensation. Safety eyewear is commonly not in use.
Plain radiographs may be helpful, but CT scanning
is the imaging modality of choice. MRI is
contraindicated if a metallic foreign body is
suspected.
These injuries may result in surprisingly little
discomfort or visual change. Prompt removal is
crucial by an ophthalmologist.
Lens dislocation
There are several conditions that cause the lens to sublux from its normal position in the posterior
chamber or dislocate both anteriorly and posteriorly. Marfan's syndrome may lead to a weakness
in the zonules that leads to a characteristic superio-temporal dislocation of the crystalline lens.
The lens capsule tends to remain intact, and the lens may be left in this position with an aphakic
correction given to the patient. Traumatic disruption of the zonules may also lead to a complete
dislocation of the lens into the anterior chamber. Once the lens has dislocated to this area, it
must be removed due to the fact that the lens may cause damage to the corneal endothelium.
Patients with lense dislocation will generally state a
complaint of blurred vision without pain. With a
dislocated lens, the patient may be noted to have
iridodonesis or a quivering of the iris when the
patient moves the eye due to a lack of lens
support. Other associated injuries, if this is the
result of a traumatic incident, should be sought.
Acute angle-closure glaucoma
Glaucoma defines conditions of the eye in which intraocular pressure is elevated either
chronically or acutely, causing progressive damage to the optic nerves. Acute angle-closure
glaucoma is a true ocular emergency. The angle between the cornea and the iris is reduced due
to a shallow anterior chamber. This causes an abnormally tight contact between the iris and lens
resulting in a relative block of flow of aqueous humor. When the pupil dilates, the sphincter irides
relaxes and allows the iris to bow forward (iris bombe') to the point of obliterating the angle
between the cornea and iris blocking the egress of aqueous humor, causing an acute rise of
intraocular pressure. Without treatment the iris becomes permanently adherent to the angle
structures, and intractable secondary glaucoma ensues.
Acute angle closure glaucoma should be
suspected with diffuse corneal edema,
especially with the associated symptoms.
The affected eye will be markedly injected and
the cornea hazy due to the fluid forced into it. The
haziness of the cornea may mask changes inside
the eye.
The anterior chamber is very shallow and the pupil semi-dilated, fixed and vertically oval.
When the intraocular pressure is felt by the digital method it is stony hard compared with
the fellow eye. The definitive test is measurement of the intraocular pressure by
tonometry. A pressure less than 21 Hg is considered normal. In acute attacks, the
pressure is markedly elevated with readings usually above 50 mmHg.
Emergent Treatment
• Head elevation to 30 degrees, improves venous drainage
• First line agents:
ƒ
Topical Beta-Adrenergic Blockade (Timolol 0.5% Dorzolamide) - decrease
aqueous humor production, beta-blockade.
ƒ Alphagan® - decreased aqueous humor secretion.
ƒ Carbonic Anhydrase Inhibitor (Acetazolamide) - decrease aqueous humor
production.
• Pilocarpine 1% - Increase aqueous humor drainage, parasympathomimetic Not effective
with IOP < 42 mmHg
• Oral Hyper-osmotic agents (1 gm/kg 20% Mannitol, 1 gm/kg 75% Glycerol) Dehydrating aqueous humor by creating blood-ocular osmotic gradient Sorbitol
should be used as an alternative in the diabetic patient.
Retinal artery occlusion
Occlusion of the central or branch retinal artery clinically leads to a sudden, painless loss of vision
in the involved eye. It also occurs in patients with systemic vascular disease, including
hypertension, ischemic heart disease, vasculitis, sickle cell disease and diabetes. In some cases,
the clot will rapidly dislodge, and the vision will return (Amaurosis fugax). If the blood flow to the
retina is interrupted for more than 90 minutes, the vision may not return even if the clot breaks
free and the circulation is restored.
Examination of the ocular fundus reveals diffuse
ischemia of the retina with a pale whitening as well as
swelling or edema of the retina with marked
decreased vascularity. The central fovea shows a
classic "cherry red spot" which is secondary to
ischemic white retina surrounding the normal
choroidal blood flow to the area of the fovea.
Treatment is directed at relief of vasospasm by
increasing the level of serum pCO2 either by
"rebreathing" techniques or by breathing a mixture of
95% oxygen and 5 per cent carbon dioxide.
Alphagan® is useful in this setting to decrease IOP
and increase the blood pressure gradient to the eye.
It is important that immediate ophthalmologic consultationis obtained if anterior chamber
paracentesis or other treatment modalities are to be attempted.
Central retinal vein occlusion
The visual deterioration is not as dramatic as that
found with arterial obstruction. The patient is usually
over 60 years old and may have diabetes or a
hyperviscosity syndrome.
CRVO has a classic "blood and thunder" fundus with
engorged tortuous veins.
The natural course of retinal vein occlusion is
variable and a spontaneous resolution is not
uncommon.
Treatment is aimed at both the underlying medical
condition and relieving the outflow obstruction. About
1/3 of cases will completely resolve with little damage
to the vision. About 1/3 stay the same with some loss
of vision, and 1/3 of cases worsen and develop more
severe loss of vision.
The worst cases may need to be treated by a laser to prevent a dangerous form of glaucoma
(neovascular glaucoma), but laser therapy will not help the vision.
Temporal arteritis
Temporal arteritis, or "giant cell arteritis", is a serious
ocular condition leading to blindness. This is an
immune disorder affecting medium sized arteries. An
associated constant, unilateral, throbbing headache
usually precedes visual changes.
Patients may note a sudden painless loss of vision in
one eye with characteristic altitudinal type of visual
field loss. Patients may have generalized symptoms
of polymyalgia rheumatica including a low grade
fever, loss of appetite, generalized weakness, and
jaw claudication. Disc examination in the acute stage
reveals a small amount of swelling and irregularity of
the disc with normal vascularity.
The lesion causing the visual loss is thought to involve obstruction of a posterior ciliary artery.
The diagnosis of this entity is confirmed by taking a biopsy of the temporal artery. Most people
with this condition have an elevated sed rate and C-reactive protein. Diagnosis, however, is made
by taking a biopsy of the temporal artery. Steroids can treat the condition, and the vision is the
unaffected eye can often be saved. Untreated, temporal arteritis can often cause visual loss in
both eyes.
Retinal detachment
A retinal detachment is usually perceived as a dark
area encroaching on, or covering, the central vision
from the periphery. These symptoms may seem to
occur suddenly, or may worsen over a short period of
time. A retinal detachment including the macula will
result in a substantial loss of vision. These injuries
can be repaired surgically with good results,
depending on the severity of the detachment, how
long it has been present, and if the macula is
involved or not.
Those with eye trauma or significant nearsightedness
may be at increased risk for retinal detachment.
The most common antecedent condition resulting in retinal detachment is a retinal tear, and
symptoms of retina tear. Patients note complaints of "floaters" and "flashing lights." An
ophthalmologist should examine a person with these symptoms promptly.
Ocular Urgencies
Lids & Lacrimal Apparatus
On examination the eyelids observe for redness, swelling, abnormal discharge, ecchymosis and
symmetry, then palpate the soft tissues and zygoma.
Periorbital Cellulitis
This is an infection of the soft tissue superficial to
the orbital septum. It is predominantly a pediatric
disorder. Periorbital cellulitis occurs secondary to
focal infection, trauma, sinusitis, or seeding of
periorbital tissue during bacteremia
Orbital Cellulitis
Orbital infections generally arise from adjacent
sinuses, and sometimes from a skin or eyelid
infection. Symptoms include pain (particularly on
movement of the eye), eyelid swelling, eye and
eyelid redness, discharge, blurred vision, eye
displacement or protrusion, and double vision.
Ocular misalignment may occur in certain positions
of gaze. Hospital admission for IV antibiotics is
warranted. Diabetics are subject to a particularly
severe and destructive fungal orbital cellulitis.
A tumor of the orbit can cause similar symptoms, although usually with less pain, redness or
discharge. The condition known as orbital pseudotumor is an inflammatory condition that can
simulate tumor or infection, but usually responds to steroids. A CT scan or MRI is indicated in
cases of orbital infection, tumor, or pseudotumor to help make the diagnosis and guide treatment.
Blepharitis
This is an infection that involves the lid margins. It
usually is a chronic infection with acute
exacerbations extending over many years.
Blepharitis is associated with rosacea and
seborrheic dermatitis.
Dacryoadenitis
This inflammation of the lacrimal gland, which may
be acute or chronic. The acute form is secondary to
infection by gram-positive cocci, usually
staphylococci. The chronic form is caused by viral
infection (e.g., mumps, EBV).
Dacryocystitis
This is inflammation of the lacrimal sac, often seen
in the setting of lacrimal duct obstruction. This
obstruction, which is usually congenital, may be
caused by infection, inflammation, trauma, or
tumor. Compression of the lid will express purulent
material from the lacrimal sac.
Canaliculitis usually is a chronic infection caused primarily by Actinomyces israelii. The lower
canaliculi are more commonly involved than the upper.
Hordeolum
An external hordeolum or “sty” is an infection of the
glands usually of Moll or Zeis by Staph aureus.
Treatment is warm compresses, antibiotic ointment
and possible incision if pointing.
The internal hordeolum involves is an acute
Meibomian gland abscess with the same treatment
as the external.
Chalazion
This nontender chronic granulomatous
inflammation of a Meibomian gland and may be
distinguished by absence of acute inflammatory
signs. Treatments may involve by an
ophthalmologist.
Conjunctival Disorders
The transparent outer coat of the eyeball forming the anterior wall of the aqueous chamber and
lining the lids is termed the cornea. It is avascular and composed of 6 layers.
Pterygium
A pterygium is a wedge-shaped fibrovascular
growth of conjunctiva (the surface tissue of the
white of the eye) that extends onto the cornea.
Pterygia are benign lesions that can be found on
either side of the cornea. Thought that prolonged
exposure to ultraviolet light increases development.
Pinguecula
This degenerative condition of the conjunctiva results in a thickening and yellow nodular
formation of the normally thin transparent tissue. This is usually seen on the nasal side of the
globe. Pinguecula occurs in elderly persons and is thought to represent degeneration in the
conjunctiva as a result of exposure to wind and dust. The condition does not require medical or
surgical treatment.
Subconjunctival hemorrhage
Trauma or straining (sneezing, coughing, etc.) can
cause subconjunctival hemorrhage, although this
may be disconcerting to the patient, it is a benign
condition and should clear spontaneously within 34 weeks. The examiner must be sure to rule out
the presence of a foreign body or occult scleral
laceration.
Conjunctivitis
Conjunctivitis or inflammation of the conjunctiva
can be caused by infectious causes such as
bacteria and viruses, as well as allergic reactions to
drugs, cosmetics, pollens, and dust. Symptoms
typically include redness, discharge and pain.
Differentiating viral from bacterial conjunctivitis in
the ED can sometimes be difficult.
Patients with viral conjunctivitis often have a history of an exposure to an infected person, have
ocular discomfort rather than pain, have a diffuse watery discharge and have tender preauricular
nodes. This can be monocular or binocular. Patients with bacterial conjunctivitis usually have
marked conjunctival injection and purulent discharge. The preauricular nodes are usually not
swollen. Most conjunctivitis are actually viral but most should be treated as bacterial making sure
that both eyes are treated simultaneously, even if only one eye is affected due to high probability
of contamination to the other eye.
Vernal conjunctivitis
Vernal conjunctivitis is thought to have an allergic
basis, although this has not been proved. It appears
most often during the spring and summer. Itchy,
watery eyes characterize this condition. Affected
people may experience burning and discomfort when
they are in bright light. The underside of the eyelids
may become roughened and covered with whitish
mucus, giving them a cobblestone appearance. The
limbus may become roughened. If this tissue
extends onto the cornea, it may cause scarring and
decreased vision.
Chemosis
This swelling of the conjunctiva may result from
any cause, most commonly due to allergies.
Scleral Disorders
Yellowing of the sclera is due to jaundice or possibly medications such as antimalarial toxicity
(quinacrine), arsenic, Tylenol, amanita mushrooms, or tetrachloride. A blue sclerae are
characteristic of osteogenesis imperfecta and Ehlers-Danlos disease.
Episcleritis
Episcleritis is an inflammation of the episclera,
which is a fibrous layer between the sclera and the
conjunctiva. A patch of engorged blood vessels on
the surface of the eye. It may be associated with
mild irritation, or sometimes iritis. It may resolve
without treatment, but it also can recur, and may
affect both eyes. It sometimes is associated with
gout.
Scleritis
Scleritis is a fairly rare disorder involving
inflammation of the wall of the sclera. It is often
associated with serious medical problems, usually
autoimmune or vascular problems (rheumatoid
arthritis, polyarteritis nodosa, lupus). A symptom of
severe, “boring” eye pain is hallmark. The sclera
appears red, swollen, and a nodule may be present
which is painful to touch. Scleritis can be associated
with iritis, and in some cases with swelling under the
retina leading to visual loss.
Corneal Disorders
Corneal abrasions
Corneal abrasions are the most common corneal pathology in the emergency department. These
may present immediately or after several hours and usually are associated with pain, redness
and tearing of the eye.
This usually follows obvious trauma, although an
abrasion may occur from other causes, such as an
inturned eyelash or from an eyelid infection
(blepharitis). Symptoms include pain, redness,
tearing, sensitivity to light, and blurred vision. The
"foreign body" sensation can be severe, and often
people describe symptoms of a "rock was rolling
around under the eyelid". What is being felt is this
extremely sensitive exposed part of the cornea.
If trauma is involved, the eye must be thoroughly examined to rule out and other injury. Treatment
entails the use of antibiotic drops or ointment, or frequent use of lubricating medication. There is
risk of infection (corneal ulcer) and internal ocular inflammation (iritis) with this condition. Normally
the cornea can heal rapidly.
Corneal foreign body
Foreign material lodged in the cornea and cause
significant symptoms of pain, tearing, light sensitivity,
and blurred vision. The most common corneal foreign
body is a rusted metallic particle. These rapidly form
a rust ring of siderosis through oxidation. If not
removed, the eye becomes progressively more
irritated over a period of days with redness, pain, light
sensitivity, and tearing.
Often the particle is visible on the eye, but it may be nearly microscopic. The foreign material is
removed with a moistened q-tip or eye spud. Usually a scar remains, and there is risk of
infection.
Corneal ulcer
Corneal ulcer (or infectious keratitis) can cause
severe eye pain. With the use of extended wear
disposable contact lenses, corneal ulcers have
become more frequent. Symptoms include eye
pain, redness, tearing, foreign body sensation,
sensitivity to light, and blurred vision. In some
contact lens users, the cornea may become
somewhat insensitive to pain, and only symptoms
of redness and irritation may appear.
A corneal ulcer is a serious, vision-threatening problem. Some bacteria can be extremely
aggressive, and the cornea can actually perforate (leading to endophalmitis). For these reasons,
any corneal ulcer in a contact lens wearer must be seen by an ophthalmologist as the most likely
offending agent is Pseudomonas. Treatment may include culturing of the corneal infection, and
frequent antibiotics eyedrops. The eye may need to be re-examined on a daily basis to insure
that the treatment to being successful. Contact lenses should not be used during this time.
Herpes keratitis
Herpes simplex produces an acute infection of the
corneal epithelium causing localized pain frequently
with a foreign body sensation. Fluorescein stain
causes a classic branching or dendritic pattern.
An ABSOLUTE RULE in caring for the patient with a
red eye - DO NOT USE STEROIDS. This is the
realm of the consulting ophthalmologist.
Anterior Chamber Disorders
Acute Iritis
Iritis (uveitis) usually refers to a group of inflammatory
diseases affecting the iris, ciliary body, and choroid.
Inflammation affecting the iris and ciliary body usually
lead to symptoms of eye pain, sensitivity to light, pain
with focusing, blurred vision, eye redness, and
sometimes floaters. One or both eyes can be
affected. The symptoms of iritis that are fairly
specific to it is "contralateral photosensitivity". This
means that the eye with iritis will feel pain even if light
is shined into the OTHER eye only. Furthermore, the
eye redness in iritis is usually a "flush" of redness in a
ring around the cornea.
Slit lamp exam reveals flare cells in the anterior
chamber. Treatment is with cycloplegics and topical
steroids. Before beginning cycloplegics however,
consider secondary glaucoma as an underlying
disorder.
The differential includes toxoplasmosis, herpes,
Lyme disease, syphilis, Behçet’s syndrome, TB,
sarcoid, ankylosing spondylitis, Reiter's syndrome,
inflammatory bowel disease and juvenile rheumatoid
arthritis.
A “pseudo” form exists in association with phenothiazine toxicity and rubella.
Hyphema
Blood in the anterior chamber usually results from
blunt trauma. The, initial bleed may or may not be
significant, but over the next 5 days, the fibrinolytic
activity in the ocular chamber increases, increasing
the possibility of a second bleed that is often worse
than the first. During this period, 2% of patients with
hyphema have a second bleed. Hyphemas are not
always as noticeable as in this particular patient and
may not be visible to the naked eye.
Early on or with a mild bleed, there may only be
RBCs in the anterior chamber and not the layering
out of blood.
Seeing a “flare” on slit lamp exam can pick this up.
The treatment of hyphema consists mainly of
hospitalization, sedation, and bed rest, although there
is no conclusive evidence that this improves
prognosis.
Serious complications include an opacification of the
cornea secondary to blood staining (as pictured
here), an extension of the hemorrhage into the
vitreous cavity and intractable glaucoma.
Hypopyon
This is a collection of inflammatory cells in the
anterior chamber layering and creating a "fluid level."
This can be related to overlying corneal infections or
severe iritis. This appearance may also be seen as
tumor cells (retinoblastoma, leukemia) collect in the
anterior chamber.
Ocular Trauma
Annually, over 2.5 million Americans suffer an eye injury, and globally more than half a million
blinding injuries occur every year. Worldwide, there are some 1.6 million people who become
blind from eye injuries. Only 2-3% of all eye injuries require hospitalization, however, over 10% of
these people will lose useful vision in the injured eye.
In all injuries a complete ocular examination must be
performed to rule out associated injuries to the globe
Blunt trauma to the orbit increases the intraorbital
pressure that is dissipated through the area of less
resistance, usually the medial wall or orbital floor.
Orbital "blow-out" fracture
A conical-shaped bony orbit protects the eye. A number of injuries to the globe and orbit are
possible. The bony floor of the orbit is particularly susceptible to a type of fracture called a "blowout" fracture. Patients manifesting orbital blowout fracture always present with a history of blunt
ocular trauma. Blowout fracture is usually caused by a large (greater than 5 cm), low-velocity
object, such as a fist or a ball. Sports-related injuries are common. If the trauma is recent, the
patient may present with symptoms of pain, local tenderness and diplopia. Complaints of an
intense pressure feeling or facial swelling associated with nose blowing may also be reported.
Critical signs of recent blowout fracture include:
• edema and ecchymosis of the lid tissues
• restriction of ocular motility, especially with vertical movements
• orbital crepitus (subcutaneous emphysema)
• hypoesthesia of the ipsilateral cheek, due to entrapment of the infraorbital nerve.
The medial wall (lamina papyracea of ethmoid bone) is occasionally affected. But most
commonly, the orbital floor (the superior aspect of the maxillary bone) sustains the damage. In
orbital floor fractures, the eye may partially drop down into the maxillary sinus, causing
enophthalmos and entrapment of the inferior rectus or inferior oblique muscle. This entrapment
leads to a tethering effect, resulting in limited downgaze ability and, more notably, an inability
toward upgaze in the affected eye. While this situation can be surgically corrected in the early
stages, prolonged entrapment leads to fibrosis of the muscle (s) and permanent motility
impairment. Associated medial wall fractures may induce damage to the medial rectus muscle
and/or the lacrimal apparatus, but this is uncommon.
Cases of blunt ocular trauma with resultant crepitus
or motility restriction warrant orbital imaging
studies. Computed tomography (CT scan) is the
procedure of choice. CT is better at imaging the
bony structures of the orbit than either plain skull
films (X-ray) or MRI. Obtain both axial and coronal
scans.
Consider ophthalmologic consultation when a floor fracture with associated herniation of the
orbital contents is discovered. Generally, surgery is reserved for patients with recent trauma who
manifest significant diplopia in primary or downward gaze, or in cases of cosmetically
unacceptable enophthalmos. Cases of orbital blowout fracture do not constitute an emergency,
however, accurate diagnosis and management of the associated ocular manifestations is
paramount.
Iridodialysis results from a rupture of the iris sphincter muscle at the ciliary body. In this case a
translucency is seen along the periphery of the iris. Ophthalmologic consultation is appropriate as
intervention is warranted in cases of extensive dialysis.
Ophthalmologic Medications
Anesthetics - Anesthetics are useful for foreign body removal, irrigation procedures, and
tonometry.
• Proparacaine (1-2 drops of 0.5% solution) is considered the least irritating of topical
anesthetics with an onset of 20 seconds and duration of 10-15 minutes.
• Tetracaine (0.5% solution) is slightly irritating with a time to onset of 4 minutes and duration
of 30-40 minutes.
Mydriatics
• Anticholinergic agents (atropine, homatropine, mydriacyl, cyclopentolate) block
muscarinic receptors on the iris and ciliary body producing mydriasis and cycloplegia
(loss of accommodation). These combined mydriatic and cycloplegic agents are used to
treat uveitis and iritis.
• Sympathomimetic agents (phenylephrine) will dilates the pupil without affecting
accommodation thus permitting diagnostic mydriasis. This can be used in combination
with anticholinergics to increase pupillary dilation.
Antibiotics - Many topical preparations are available. Solutions should be applied more
frequently (q 2-4 hours) than ointments (q 4 hours). Ointments are considered more efficacious
than solutions because of higher effective concentrations, increased tissue contact time, and
resistance to dilution by tears and nasolacrimal drainage.
• Polytrim (trimethoprim sulfate/polymyxin sulfate) ophthalmic drops are the agent generally
used in the department. This is a sulfa derivative and ought be avoided in those allergic
to sulfa.
• Alternative agents include ofloxacin, ciprofloxin, erythromycin and gentamicin.
• Sodium sulfacetamide is irritating and should be avoided.
Steroids
Steroids can cause a rapid progression of herpes simplex keratitis and therefore should in
general not be prescribed in the ED without consultation with an ophthalmologist. This disease
needs ophthalmologic consultation since progression can cause destruction of the cornea and
subsequent visual impairment.
Slit Lamp Examination
Emergency physicians and ophthalmologists are the only physicians who regularly use the slit
lamp. Biomicroscopy, or the slit lamp examination, is a necessary tool for the accurate evaluation
and treatment of patients with ocular complaints. It is most useful for evaluating corneal injuries,
foreign bodies, and anterior segment pathology (e.g., iritis). Evaluation of the red eye should
routinely include a slit lamp examination.
The slit lamp includes three parts:
A microscope
A lighting device with various filters
A mechanical assembly for mounting the device and positioning the patient and examiner.
Methods
Once the examiner and patient are properly positioned, the examination should proceed under
low power from anterior to posterior. The beam of white light is generally directed obliquely (45
degrees) at the cornea with maximum height and minimal width. In a sweeping motion first scan
the surface of the bulbar conjunctiva and cornea paying particular attention to corneal
endothelium and stroma observing for clarity, shape and regularity of the anterior and posterior
surfaces. Next, focus slightly deeper and examine the anterior chamber for cells (RBC or WBC)
and flare (protein). Note the depth of the anterior chamber. And, finally, examine the surface of
the lens. In order to detect the most subtle cell and flare (signs of intraocular inflammation) the
light may be adjusted to a small, square beam directed obliquely at the cornea and allow the
posterior part of this beam to pass through the pupil and ocular lens rather than illuminating a
section of iris. This technique minimizes the scatter of light as the examiner slowly moves the
focal plane of the lamp through the anterior chamber observing for subtle evidence of cell and
flare. Lid eversion should next be performed if a foreign body is suspected. Fluorescein staining
and a repeat examination of the cornea will detect and delineate corneal epithelial defects. This
concludes the slit lamp examination. These procedures will be reviewed in-depth during the
laboratory session.
Foreign Body Removal
Indications
Extraocular foreign body removal is always indicated. When the patient is extremely
uncooperative or when a deeply embedded object penetrates the globe or multiple objects
immediate ophthalmologic consultation will be required. Once located, a foreign body that cannot
be removed from the cornea or conjunctivae will require removal with a cotton-tipped applicator
(for conjunctival foreign bodies), needle, or spud device.
Methods
The necessary equipment includes topical anesthetic, sterile cotton-tipped applicators,
fluorescein dye, eye spud and syringe with beveled needle, and patches. The patient should be
anesthetized with topical anesthetic and with the head securely positioned in the slit lamp the
patient is instructed to fix his gaze on a stationary object. The examiner braces his hands against
the patient’s head or on the frame of the lamp and tangentially approaches the foreign body with
the cotton-tipped applicator (conjunctivae), needle, or spud device gently sweeping or picking at
the embedded foreign body. The cornea is surprisingly resilient and difficult to penetrate with
these procedures. Rust rings are the result of embedded metallic foreign bodies and can be
difficult to remove. If they can not be entirely débrided with a spud, needle, or rotating burr at the
time of initial foreign body removal the patient may return in 24-48 hours after which time the iron
particles will generally coalesce allowing removal at that time in one “plug”. Patching may be
helpful for comfort and healing of the corneal lesions produced as a result of the foreign body and
its removal.
Complications
Complications are rare. Incomplete removal of the foreign body is the most common problem.
Ophthalmologic referral is necessary in this situation to prevent prolonged inflammation and/or
scarring. Conjunctivitis may develop. Perforation of the globe is exceedingly rare.
Tonometry
Introduction
Tonometry is the measurement of intraocular pressure by application of a device that directly
measures the resistance of the globe to indentation of an applied force. Sudden elevation of
intraocular pressure may occur as a result of trauma or acute angle-closure glaucoma. This
pressure may impair retinal blood flow.
Indications
Special situations in which tonometry is require include:
• Confirmation of the diagnosis of acute angle closure glaucoma.
• Determination of intraocular pressure following blunt trauma.
• Determination of intraocular pressure in a patient with iritis.
• Screening of patients at risk for open-angle glaucoma.
• Screening of patients with glaucoma and hypertension.
Methods
Digital palpation (tactile method) may reveal intraocular hypertension and is performed by
stabilizing the fingers of both hands on the temple and forehead of the patient while alternately
balloting the globe of one eye with the index finger of each hand. Applanation tonometry is
performed with a special instrument attached to the slit lamp that applies a plane surface over the
surface of the cornea while visualizing crescentic rings enhanced with fluorescein dye through the
slit lamp. Although accurate, applanation tonometry is difficult to do and no more accurate than
the Tono-Pen®. All of the above tonometric methods, except for digital palpation, require topical
anesthetic administration in order to make contact with the cornea.
Indentation of the cornea (impression method)
may be performed with the Tono-Pen®. The
Tono-Pen® is quick, accurate and may be used
sitting or recumbent but the device is expensive
and not particularly intuitive to use. The Tono-Pen
uses disposable latex condoms.
Complications
Infectious diseases may be transmitted if appropriate precautions are not utilized. The devices
may abrade the cornea and significant blunt or perhaps even penetrating injuries are hypothetical
concerns. If a perforated globe is present or suspected tonometry should not be performed due to
the risk of extruding intraocular contents.
References & Suggested Reading
1. Scott JL and Ghezzi KT, Emergency Treatment of the Eye, Emergency Medicine Clinics of
North America, volume 13: 3, pp 1-712, August 1995.
2. Barr DH, Samples JR, and Hedges JR, Ophthalmologic Procedures, chapter 85 in Clinical
Procedures in Emergency Medicine, edited by Roberts JT and Hedges JR, 2nd edition, WB
Saunders Co., pp 995-1019, pub 1991.
3. Knoop K and Trott A, Ophthalmologic Procedures in the Emergency Department - Part I:
Immediate Sight Saving Procedures, Academic Emergency Medicine, vol 1:4, pp 408-13,
Jul/Aug 1994.
4. Knoop K and Trott A, Ophthalmologic Procedures in the Emergency Department - Part II:
Routine Evaluation Procedures, Academic Emergency Medicine, vol 2:2, pp 144-50, Feb
1995.
5. Knoop K and Trott A, Ophthalmologic Procedures in the Emergency Department - Part III: Slit
Lamp Use and Foreign Bodies, Academic Emergency Medicine, vol 2:3, pp 224-30, Mar
1995..