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Emergency Medicine Atlas > Part 1. Regional Anatomy > Chapter 4. Ophthalmic Trauma >

Corneal Abrasion

Associated Clinical Features

Corneal abrasions are heralded by the acute onset of eye discomfort accompanied by tearing and a foreign-body sensation. Conjunctival injection may also be noted. If the area of abrasion is large or central, visual acuity may be affected. Large abrasions or delays in seeking care may be accompanied by photophobia and headache from ciliary muscle spasm. Associated findings or complications include traumatic iritis, hypopyon, or a corneal ulcer (described in Chap. 2). Examination before and after instillation of fluorescein, preferably with a slit lamp, usually reveals the defect (Figs. 4.1 and 4.2). Fluorescein pools and stains the area where corneal epithelium has been denuded.

Figure 4.1

Corneal Abrasion Seen under magnification from the slit lamp, corneal abrasion can sometimes be appreciated without fluorescein staining. This abrasion is seen without using the cobalt blue light. (Courtesy of Harold Rivera.)

Figure 4.2

Corneal Abrasion The same abrasion as Fig. 4.1 is seen under magnification from the slit lamp with fluorescein stain using the cobalt blue light. (Courtesy of Harold Rivera.)

Differential Diagnosis

Corneal foreign body, conjunctivitis, conjunctival foreign body, iritis, and corneal ulcer can present with similar complaints.

Emergency Department Treatment and Disposition

Instillation of topical anesthetic drops permits a better examination and relieves pain. A short-acting cycloplegic (e.g., cyclopentolate 0.5%, homatropine 5%) may reduce ciliary spasm and pain and should be considered in patients with larger abrasions or in those who complain of headache or photophobia. Topical antibiotic drops or ointment—preferably broad-spectrum agents such as gentamicin, sulfacetamide, or erythromycin—are used to prevent secondary bacterial infection. A soft double-layer patch may also be applied. Neither treatment with topical antibiotics nor patching has been scientifically validated, and routine use of these practices has been called into question. Follow-up is required for any patient who is still symptomatic after 12 h.

Clinical Pearls

1. Only sterile fluorescein strips should be used, since the corneal epithelium, the primary barrier to infection, has been potentially disrupted.

2. Mucus may simulate the fluorescein uptake, but its position changes with blinking.

3. Multiple linear corneal abrasions, the "ice-rink sign," may result from the adherence of a foreign body to the conjunctiva under the lid (Fig. 4.3). The lid should always be everted to rule out a retained foreign body.

4. A high index of suspicion of a perforating injury should be maintained for any abrasion that occurs as a result of grinding or striking metal on metal.

5. Fluorescein streaming away from an "abrasion" (Seidel's test) may be an indication of a corneal perforation.

Figure 4.3

Foreign Body under the Upper Lid Lid eversion is an essential part of the eye examination. (Courtesy of Kevin J. Knoop, MD, MS.)

Corneal Foreign Body

Associated Clinical Features

Patients typically give a history of something in the eye or complain of foreign-body sensation. If the foreign body overlies the cornea, the patient's vision may be affected. There may be tearing, conjunctival injection, and ciliary flush (Fig. 4.4). If several hours have elapsed since the occurrence of the injury, there may be headache and photophobia in addition to the above signs and symptoms.

Figure 4.4

Foreign Body on the Cornea A foreign body is lodged at 10 o'clock on the cornea. Note the localized ciliary flush in the surrounding conjunctiva at the limbus. (Courtesy of Kevin J. Knoop, MD, MS.)

Differential Diagnosis

The most important consideration in the differential is the possibility of a penetrating injury to the globe. A meticulous history about the mechanism of injury (grinding or metal on metal) must be elicited. Conjunctival foreign body, corneal abrasion, intraocular foreign body, conjunctivitis, iritis, and glaucoma should also be considered.

Emergency Department Treatment and Disposition

If superficial, removal of the foreign body with a moist cotton-tipped applicator may be attempted; if unsuccessful, an eye spud or small (25-gauge) needle may be used. After removal, if a residual corneal abrasion is present, instill an antibiotic solution or ointment. A "short-acting" cycloplegic (e.g., cyclopentolate 0.5%) should be considered in patients with complaints of headache or photophobia. Metallic foreign bodies are often accompanied by a "rust ring" discoloration of the surrounding corneal epithelium (Fig. 4.5). Removal of the rust ring can be attempted, either with a needle or preferably with a small burr drill device available commercially. Alternatively, the patient may be referred to an ophthalmologist the following day.

Figure 4.5

"Rust Ring" A rust ring has formed from a foreign body (likely metallic) in this patient. A burr drill can be used for attempted removal, which, if unsuccessful, can be reattempted in 24 h. (Courtesy of Kevin J. Knoop, MD, MS.)

Clinical Pearls

1. Treatment of a suspected penetrating injury to the globe includes immediate referral, eye rest, protective patching (Figs. 4.6, 4.7), and elevation of the head of the bed.

2. If history of ocular penetration is present, a diligent search for a foreign body is indicated. X-ray may identify the foreign body (Fig. 4.8), but computed tomography (CT) is the diagnostic study of choice.

3. Be sure to evert the upper lid and search carefully for a foreign body. A foreign body adherent to the upper lid abrades the cornea, producing the "ice-rink" sign, caused from multiple linear abrasions.

4. If a rust ring is present from a metallic foreign body, its removal can be attempted, or the patient may await ophthalmology follow-up in 24 h.

5. Multiple small corneal foreign bodies (e.g., glass or sand) may be removed by irrigating with normal saline or tap water. The instillation of a topical anesthetic facilitates the irrigation process.

Figure 4.6

Protective Metal (Fox) Shield A protective shield is used in the setting of a suspected or confirmed perforating injury. (Courtesy of Kevin J. Knoop, MD, MS.)

Figure 4.7

Protective Shield A protective shield is readily fashioned from a paper cup if a metal shield is not available. (Courtesy of Kevin J. Knoop, MD, MS.)

Figure 4.8

Intraocular Foreign Body A metallic foreign body is seen on a plain radiograph and—with comparison with a lateral film—indicates the presence of an intraocular foreign body. (Courtesy of Department of Ophthalmology, Naval Medical Center, Portsmouth, VA.)

Eyelid Laceration

Associated Clinical Features

Eyelid lacerations should always prompt a thorough search for associated injury to the globe, penetration of the orbit, or involvement of surrounding structures (e.g., lacrimal glands, ducts, puncta) (Fig. 4.9). Depending on the mechanism of injury, a careful exclusion of foreign body may be indicated.

Figure 4.9

Eyelid and Adnexa Anatomy Ocular trauma should prompt examination of surrounding anatomic structures for associated injuries.

Differential Diagnosis

Laceration of the levator palpebrae musculature or tendinous attachments, laceration of the canthal ligamentous support, division of the lacrimal duct or puncta, and penetration of the periorbital septum should all be considered.

Emergency Department Treatment and Disposition

Eyelid lacerations involving superficial skin can be repaired with 6-0 nonabsorbable interrupted sutures, which should remain in place for 3 days. Lacerations through an anatomic structure called the gray line (see Fig. 4.9), situated on the palpebral edge, require diligent reapproximation and should be referred. Other injuries that require specialty consultation for repair include:

—Lacerations through the lid margins: these require exact realignment to avoid entropion or extropion.

—Deep lacerations through the upper lid that divide the levator palpebrae muscles or their tendinous attachments: these must be repaired with fine absorbable suture to avoid ptosis.

—Lacrimal duct injuries: these are repaired by stenting of the duct, otherwise excessive spilling of tears (epiphora) will result.

—Medial canthal ligaments: these must be repaired to avoid drooping of the lids.

The most important objectives are to rule out injury to the globe and to search diligently for foreign bodies.

Clinical Pearls

1. Lacerations of the medial one-third of the lid (Fig. 4.10) should always raise suspicion for injury to the lacrimal ducts or puncta as well as the medial canthal ligament.

2. A small amount of adipose tissue seen within a laceration is a sign that perforation of the orbital septum has occurred (since there is no subcutaneous fat in the lids themselves).

3. Injuries involving the orbital septum carry a higher than normal risk of globe injury and intraorbital foreign body as well as a higher risk for orbital cellulitis. A CT scan and specialty consultation should be considered.

4. Any injury to the lids involving tissue loss or avulsion should be referred for specialty consultation.

Figure 4.10

Eyelid Laceration This laceration involving the medial third of the lid clearly violates the canalicular structures. The patient was struck by a person wearing a ring. (Courtesy of Kevin J. Knoop, MD, MS.)

Hyphema

Associated Clinical Features

Injury to the anterior chamber that disrupts the vasculature supporting the iris or ciliary body results in a hyphema. The blood tends to layer and because of gravity forms a meniscus (Fig. 4.11). Symptoms can include pain, photophobia, and possibly blurred vision secondary to obstructing blood cells. Nausea and vomiting may signal a rise in intraocular pressure (glaucoma) caused by blockage of the trabecular meshwork by blood cells or clot.

Figure 4.11

Hyphema This hyphema has almost completely layered while the patient's head was tilted. Note the hazy greenish area at 6 o'clock in contrast to the remainder of the blue iris. This represents blood circulating in the anterior chamber that has not yet layered. (Courtesy of Kevin J. Knoop, MD, MS.)

Differential Diagnosis

Hypopyon (pus within the anterior chamber), vitreous hemorrhage, iridodialysis, penetrating injury to the globe, and intraocular foreign body should be considered.

Emergency Department Treatment and Disposition

Prevention of further hemorrhage is the first goal. The patient should be kept at rest in the supine position with the head elevated slightly. A hard eye shield should be used to prevent further trauma from manipulation. Oral or parenteral pain medication and sedatives are appropriate, but avoid agents with antiplatelet activity such as nonsteroidal anti-inflammatory drugs (NSAIDs). Antiemetics should be used if the patient has nausea. Further treatment is at the discretion of specialty consultants but may include topical and oral steroids, antifibrinolytics such as aminocaproic acid, or surgery. Intraocular pressure (IOP) should be measured in all patients unless there is a suspicion of penetrating injury to the globe. If elevated, IOP should be treated with appropriate agents including topical beta blockers, pilocarpine, and, if needed, osmotic agents (mannitol, sorbitol) and acetazolamide. The need for admission for small hyphemas is variable, since some centers admit all whereas others individualize treatment. Ophthalmologic consultation is warranted to determine local practices.

Clinical Pearls

1. The patient should be told specifically not to read or watch television, as these activities result in greater than usual ocular activity.

2. Depending on the severity of the initial hyphema, rebleeding may occur in 10 to 25% of patients, commonly in 2 to 5 days as the original clot retracts and loosens.

3. Blood that is not absorbed from the anterior chamber may infiltrate and stain the cornea, leaving a brown discoloration.

4. An "eightball" or total hyphema occurs when blood fills the entire anterior chamber. These lesions require surgical evacuation.

5. Patients with sickle cell and other hemoglobinopathies are at risk for sickling of blood inside the anterior chamber (Fig. 4.12). This can cause a rise in IOP from physical obstruction of the trabecular meshwork.

Figure 4.12

Hyphema A small hyphema (about 5%) in a patient with sickle cell disease. (Courtesy of Dallas E. Peak, MD.)

Iridodialysis

Associated Clinical Features

Traumatic iridodialysis is the result of an injury, typically blunt trauma, that pulls the iris away from the ciliary body. The resulting deformity appears as a lens-shaped defect at the outer margin of the iris (Fig. 4.13). Patients may present complaining of a "second pupil." As the iris pulls away from the ciliary body, a small amount of bleeding may result. Look closely for associated traumatic hyphema.

Figure 4.13

Traumatic Iridodialysis The iris has pulled away from the ciliary body as a result of blunt trauma. (Courtesy of Department of Ophthalmology, Naval Medical Center, Portsmouth, VA.)

Differential Diagnosis

Traumatic hyphema, penetrating injury to the globe, scleral rupture, intraocular foreign body, and lens dislocation causing billowing of the iris should all be considered.

Emergency Department Treatment and Disposition

A remote traumatic iridodialysis requires no specific treatment in the ED. Recent history of ocular trauma should prompt a diligent slit-lamp examination for associated hyphema or lens discoloration. If hyphema is present, it should be treated as discussed (see "Hyphema", above). Pure cases of iridodialysis may be referred for specialty consultation to exclude other injuries; if the defect is large enough to result in monocular diplopia, surgical repair may be necessary.

Clinical Pearls

1. The examination should carefully exclude posterior chamber pathology and hyphema.

2. A careful review of the history to exclude penetrating trauma should be made. If the history is unclear, CT scan may be used to exclude the presence of intraocular foreign body.

3. A careful examination includes searching for associated lens dislocation.

Lens Dislocation

Associated Clinical Features

Lens dislocation may result from a sudden blow to the globe with resultant stretching of the zonule fibers that hold the lens in place (Fig. 4.14). The patient may experience symptoms of monocular diplopia or gross blurring of images, depending on the severity of the injury. The edge of the subluxed lens may be visible when the pupil is dilated (Fig. 4.15). If all the zonule fibers tear and the lens is dislocated, it may lodge in the anterior chamber or the vitreous.

Figure 4.14

Lens Dislocation Lens dislocation revealed during slit-lamp examination. Note the zonule fibers, which normally hold the lens in place. (Courtesy of Department of Ophthalmology, Naval Medical Center, Portsmouth, VA.)

Figure 4.15

Lens Dislocation The edge of this dislocated lens is visible with the pupil dilated as an altered red reflex. (Courtesy of Department of Ophthalmology, Naval Medical Center, Portsmouth, VA.)

Differential Diagnosis

Marfan's syndrome, tertiary syphilis, and homocystinuria may be present and should be considered in patients presenting with lens dislocation.

Emergency Department Treatment and Disposition

Almost all cases require surgery if the lens is totally dislocated; partial subluxations may require only a change in refraction.

Clinical Pearls

1. Patients may experience lens dislocation with seemingly trivial trauma if they have an underlying coloboma of the lens (see Fig. 4.20), Marfan's syndrome, homocystinuria, or syphilis.

2. Iridodonesis is a trembling movement of the iris noted after rapid eye movements and is a sign of occult posterior lens dislocation.

Open Globe

Associated Clinical Features

Open globe injuries resulting from penetrating trauma can be subtle and easily overlooked. All are serious injuries. Signs to look for are loss of anterior chamber depth caused by leakage of aqueous humor, a teardrop-shaped pupil, or prolapse of choroid through the wound (Fig. 4.16).

Figure 4.16

Open Globe This injury is not subtle; extruded ocular contents (vitreous) can be seen; a teardrop pupil is also present. (Courtesy of Alan B. Storrow, MD.)

Differential Diagnosis

Iridodialysis, corneal foreign body, and scleral rupture may have similar presentations.

Emergency Department Treatment and Disposition

All open globe injuries require specialty consultation. A Fox (metal) eye shield should be placed over the affected eye. No attempts to examine, measure pressures, or manipulate the eye should be made. Intravenous antibiotics to cover gram-positive organisms are appropriate. Sedation and aggressive pain management are crucial and should be used liberally to prevent or decrease expulsion of intraocular contents due to crying, activity, or vomiting. Antiemetics should be given if nausea is present. Tetanus immunization should be updated. Many open globe injuries are associated with other significant blunt trauma injuries.

Clinical Pearls

1. When a large foreign body such as a pencil or nail protrudes from the globe, resist the temptation to remove it. Such objects should be left in place until definitively treated in the operating room.

2. Control of pain, activity, and nausea may be sight-saving and requires proactive use of appropriate medications.

3. Use of lid hooks, retractors (Fig. 4.17), or even retractors fashioned from paper clips (Fig. 4.18) is preferred to open the eyelids of trauma victims with blepharospasm or massive swelling. Attempts to do this with fingers can inadvertently increase the pressure on the globe.

4. Penetrating globe injuries are a relative contraindication to the sole use of depolarizing neuromuscular blockade (e.g., succinylcholine). Pretreatment with a small dose of a nondepolarizing agent should be given to abolish the fasciculations and resultant increased intraocular pressure.

Figure 4.17

Eyelid Retractors Retractors are used to gain exposure without applying pressure to the globe. (Courtesy of Dallas E. Peak, MD.)

Figure 4.18

Eyelid Retractors Retractors fashioned from paper clips can safely be used when standard retractors are not available. (Courtesy of Kevin J. Knoop, MD, MS.)

Scleral Rupture

Associated Clinical Features

A forceful blow to the eye may result in a scleral rupture. The diagnosis is obvious when orbital contents are seen spilling from the globe itself. The diagnosis may be more occult in situations where only a tiny rent in the sclera has occurred. When rupture occurs at the limbus, a small amount of iris may herniate, resulting in an irregularly shaped pupil called a teardrop pupil (Fig. 4.19). A teardrop pupil may also be the result of a penetrating foreign body. Mechanism is the key to distinguishing these two causes. Another associated finding is bloody chemosis of the bulbar conjunctiva over the area of scleral rupture. This may be distinguished from a simple subconjunctival hematoma by bulging of the conjunctiva.

Figure 4.19

Corneal-Scleral Rupture A teardrop pupil is present, with a small amount of iris herniating from a rupture at the limbus. These injuries may initially go unnoticed. (Courtesy of Dallas E. Peak, MD.)

Differential Diagnosis

Subconjunctival hematoma, nontraumatic bloody chemosis, corneal-scleral laceration, intraocular foreign body, iridodialysis, and traumatic lens dislocation may have a similar presentation. A coloboma of the iris (Fig. 4.20) may appear similar to a teardrop pupil.

Figure 4.20

Iris Coloboma Iris coloboma is a congenital finding resulting from incomplete closure of the fetal ocular cleft. It appears as a teardrop pupil and may be mistaken for a sign of scleral rupture. (Courtesy of Department of Ophthalmology, Naval Medical Center, Portsmouth, VA.)

Emergency Department Treatment and Disposition

Urgent specialty consultation and operative management are mandatory. The eye should be protected by a Fox metal eye shield, and all further examination and manipulation of the eye should be discouraged to prevent prolapse or worsening prolapse of choriouveal structures. Tetanus status should be addressed. Intravenous antibiotics to cover suspected organisms are appropriate. Adequate sedation and use of parenteral analgesics is encouraged. Antiemetics should be given proactively, since vomiting may result in further prolapse of intraocular contents. CT scanning should be considered if the presence of a foreign body is suspected.

Clinical Pearls

1. The eyeball may appear deflated or the anterior chamber excessively deep. Intraocular pressure will likely be decreased, but measurement should be avoided, since this may worsen herniation of intraocular contents.

2. Rupture usually occurs where the sclera is the thinnest, at the point of attachment of extraocular muscles and at the limbus.

3. Bloody chemosis from scleral rupture is distinguished from subconjunctival hematoma by bulging of the conjunctiva. A subconjunctival hematoma is flat in appearance (see Fig. 4.22).

4. A teardrop pupil may easily be overlooked in the triage process or in the setting of multiple traumatic injuries.

5. Seidel's test (instillation of fluorescein and observing for fluorescein streaming away from the injury) may be used to diagnose subtle perforation (Fig. 4.21).

Figure 4.21

Seidel Test A positive Seidel test shows aqueous leaking through a corneal perforation while being observed with the slit lamp. (Courtesy of John D. Mitchell, MD. Used with permission from Tintinalli JE et al: Emergency Medicine: A Comprehensive Study Guide, 5^th ed. New York: McGraw-Hill; 2000.)

Subconjunctival Hemorrhage

Associated Clinical Features

A subconjunctival hemorrhage or hematoma occurs with often trivial events such as a cough, sneeze, Valsalva maneuver, or minor blunt trauma. The patient may present with some degree of duress secondary to the appearance of the bloody eye. The blood is usually bright red and appears flat (Fig. 4.22). It is limited to the bulbar conjunctiva and stops abruptly at the limbus. This appearance is important to differentiate the lesion from bloody chemosis, which can occur with scleral rupture. Aside from appearance, this condition does not cause the patient any pain or diminution in visual acuity.

Figure 4.22

Subconjunctival Hemorrhage Subconjunctival hemorrhage in a patient with blunt trauma. The flat appearance of the hemorrhage indicates its benign nature. (Courtesy of Dallas E. Peak, MD.)

Differential Diagnosis

Scleral rupture, nontraumatic bloody chemosis (Fig. 4.23), conjunctivitis, iritis, corneal-scleral laceration, severe hypertension, and coagulopathy may have a similar appearance or presentation.

Figure 4.23

Bloody Chemosis "Bloody chemosis" was confused with "subconjunctival hemorrhage" in this patient with no history of trauma and positive cranial nerve palsies. Cavernous sinus thrombosis was diagnosed. (Courtesy of Eric Einfalt, MD.)

Emergency Department Treatment and Disposition

No treatment is required. The patient should be told to expect the blood to be resorbed in 2 to 3 weeks.

Clinical Pearls

1. Subconjunctival hematoma may be differentiated from bloody chemosis by the flat appearance of the conjunctival membranes.

2. A subconjunctival hematoma involving the extreme lateral globe after blunt trauma is very suspicious for zygomatic arch fracture.

3. Patients with nontraumatic bloody chemosis should be evaluated for an underlying metabolic (coagulopathy) or structural (cavernous sinus thrombosis) disorder.

Traumatic Cataract

Associated Clinical Features

Any trauma to the eye that disrupts the normal architecture of the lens may result in the development of a traumatic cataract—a lens opacity (Fig. 4.24). The mechanism behind cataract formation involves fluid infiltration into the normally avascular and acellular lens stroma. The lens may be observed to swell with fluid and become cloudy and opacified. The time course is usually weeks to months following the original insult. Cataracts that are large enough may be observed by the naked eye. Those that are within the central visual field may cause blurring of vision or distortion of light around objects (e.g., halos).

Figure 4.24

Traumatic Cataract This traumatic cataract is seen as a large lens opacity overlying the visual axis. A traumatic iridodialysis is also present. (Courtesy of Dallas E. Peak, MD.)

Differential Diagnosis

Lens dislocation, intraocular foreign body, hypopyon, corneal abrasion, and hyphema can present with similar complaints. History and physical examination are helpful in discriminating most of these conditions from traumatic cataract.

Emergency Department Treatment and Disposition

No specific treatment is rendered in the ED for cases of delayed traumatic cataract. Routine ophthalmologic referral is indicated for most cases.

Clinical Pearls

1. Traumatic cataracts are frequent sequelae of lightning injury. All lightning-strike victims should be warned of this possibility.

2. Cataracts may also occur as a result of electric current injury to the vicinity of the cranial vault.

3. Cataracts can be easily examined using the +10-diopter setting on an ophthalmoscope or in more detail with a slit lamp.

4. Leukocoria results from a dense cataract, which causes loss of the red reflex.

5. If a cataract develops sufficient size and "swells" the lens, the trabecular meshwork may become blocked, producing glaucoma.

Chemical Exposure

Associated Clinical Features

Most symptomatic ocular exposures involve either immediate or delayed onset of eye discomfort accompanied by one or more of the following: itching, tearing, redness, photophobia, blurred vision, and/or foreign-body sensation. Conjunctival injection or chemosis may be noted on examination. Abrupt onset of more severe symptoms may indicate exposure to caustic alkaline or acidic substances and should be regarded as a true ocular emergency. Exposure to defensive sprays or riot-control agents (e.g., Mace or tear gas) causes immediate onset of severe ocular burning, intense tearing, blepharospasm, and irritation of the mucous membranes of the nose and oropharynx. Chemical conjunctivitis in the newborn may stem from the use of silver nitrate drops at delivery for prophylaxis against Neisseria gonorrhoeae. Many hospitals now favor erythromycin-based ointments.

Differential Diagnosis

Alkali or acid exposure, corneal foreign body, corneal abrasion, infectious conjunctivitis, and conjunctival foreign body should be considered.

Emergency Department Treatment and Disposition

Treatment should begin in the prehospital arena with immediate and copious irrigation. The patient who presents acutely with possible caustic exposure should be triaged to immediate treatment. An attempt should be made to determine the pH of the conjunctival sac with a broad-range pH paper, though this determination should not delay the initiation of treatment. Instillation of topical anesthetic drops will permit a better examination. The conjunctiva should be closely examined for concretions or foreign body, with eversion of the upper lid. Any debris should be removed with a moistened cotton-tipped applicator. If pH determination demonstrates acid or alkali exposure, irrigation with warmed normal saline (NS) or lactated ringers (LS) (preferred) solution should begin, using 1-L bags connected through standard intravenous tubing to a Morgan lens. A minimum of 2-L should be instilled, followed by a recheck of the pH or reassessment for continued symptoms. If a normal tear film pH of 7.4 has not been achieved, irrigation should be continued. Alkali exposures may cause severe injury due to liquifaction necrosis, which penetrates the deeper tissues (Fig. 4.25). Acids produce a coagulative necrosis, which creates a barrier to further penetration.

Figure 4.25

Alkali Burn Diffuse opacification of the cornea occurred from a "lye" burn to the face. (Courtesy of Stephen Corbett, MD.)

Irrigation should be strongly considered after chemical exposure to a non–acid or alkali source. Many chemicals merely cause irritative symptoms; however, some may also denude the corneal epithelium and inflame the anterior chamber. All patients should undergo slit-lamp examination to document corneal injuries (e.g., abrasions, punctate erosions, opacities) or anterior chamber inflammation. Antibiotic drops may be indicated, particularly if corneal injury is noted. Cycloplegics may be of benefit as well to reduce ciliary spasm and pain in these cases.

Clinical Pearls

1. Immediate onset of severe symptoms calls for immediate treatment and should prompt consideration of alkali or acid exposure.

2. Determination of ocular pH should be made in all cases of chemical exposure.

3. Prolonged (up to 24 h) irrigation may be needed for alkaline exposures.

4. Concretions from the exposure agent may form deep in the conjunctival fornices and must be removed to prevent further injury (Fig. 4.26).

5. Corneal abrasions or punctate erosions may be a direct result of the chemical agent or from treatment with irrigation or placement of the Morgan lens.

Figure 4.26

Caustic Burn Adhesions (Symblepharon) Scarring of both palpebral and bulbar conjunctivae results in severe adhesions between the lids and the globe. (Courtesy of Arden H. Wander, MD.)