Emergency Medicine Hub / Ambulatory & Fast Track • 3 min read • 5 sections

Ambulatory Ophthalmology & Corneal Abrasions

Essential fast-track emergency guide to outpatient ophthalmology and acute ocular trauma. Covers step-by-step slit-lamp examinations, fluorescein staining patterns (abrasions vs. herpes dendrites vs. foreign bodies), the Seidel test for full-thickness globe penetration, the strict prohibition of eye patching in contact lens wearers, corneal rust ring removal, chemical burn Morgan lens irrigation, and the black-box danger of outpatient topical anesthetics.

Resuscitation Quick Actions • First 2 Minutes

High-Acuity

Visual Acuity First

Always document visual acuity in both eyes before performing any examination or procedural intervention (except in acute chemical eye burns where IMMEDIATE irrigation takes priority).

Chemical Eye Burns

Immediate copious Morgan lens irrigation with 1-2 L of normal saline or lactated Ringer's; check ocular pH with litmus paper; target neutral pH 7.0-7.4 checked 10 minutes AFTER stopping irrigation.

Seidel Test for Open Globe

Concentrated fluorescein over suspected wound under cobalt blue light; streaming waterfall of clear aqueous humor diluting the orange fluorescein confirms full-thickness perforation. STOP exam, place rigid Fox shield, zero pressure, NPO, IV antiemetics, immediate ophthalmology consult.

Contact Lens Abrasion

Treat with topical antipseudomonal fluoroquinolone (Ciprofloxacin 0.3% or Ofloxacin 0.3% drops every 2 hours) or Tobramycin. NEVER PATCH. Mandatory 24-hour ophthalmology follow-up.

Foreign Body & Rust Ring

Remove superficial metal with 25-27G needle bevel-up under slit lamp; rust rings soften within 24-48 hours and can be burred with an Algerbrush in clinic or by ophthalmologist.

Topical Anesthetic Warning

Proparacaine 0.5% (1-2 drops) is strictly for in-ED diagnostic exam; NEVER prescribe or dispense topical anesthetics for home use.

Bottom-Line Clinical Pearl

NEVER patch an eye in a contact lens wearer with a corneal abrasion. Patching creates a warm, hypoxic, closed incubator that allows Pseudomonas aeruginosa to cause fulminant corneal melting within 24 hours. NEVER dispense topical proparacaine or tetracaine for outpatient discharge; repeated use destroys the corneal epithelium, leading to permanent corneal perforation.

1. Systematic Ocular Examination & Diagnostic Staining

Every acute red or painful eye in the emergency department must be evaluated through a standardized four-phase sequence:

Examination Phase	Clinical Technique & Finding	Pathology & Emergency Action
1. Visual Acuity (VA)	Check Snellen eye chart at 20 ft or handheld near card at 14 inches with patient wearing corrective lenses	MANDATORY legal baseline before touching eye. If patient cannot read chart, test Count Fingers (CF), Hand Motion (HM), and Light Perception (LP). Acuity loss implies deep pathology (ulcer, open globe, hyphema).
2. Pupillary & Slit-Lamp Exam	Check direct/consensual reflexes; inspect anterior chamber depth, cells/flare (iritis), and hyphema	Teardrop-shaped or peaked pupil pointing toward a limbal defect is pathognomonic for full-thickness GLOBE RUPTURE with iris herniation. Hyphema requires bed rest at 30-45° elevation and ophtho consult.
3. Seidel Test (Globe Perforation)	Moisten fluorescein strip with one drop of saline and apply directly over suspected laceration. Inspect under cobalt blue light without instilling excess drops	POSITIVE SEIDEL: Clear aqueous humor leaks from the anterior chamber, diluting concentrated orange fluorescein into a flowing bright green stream ('waterfall sign'). Confirms PENETRATING EYE INJURY. Place rigid Fox shield; DO NOT measure IOP; STAT ophtho consult.
4. Upper Eyelid Eversion	Roll upper eyelid over a cotton-tipped applicator while patient looks downward	Inspect superior tarsal plate for embedded foreign bodies, grit, or fiberglass. Vertical linear 'ice-skate track' scratches on the cornea are pathognomonic for a foreign body trapped under the upper lid.

Strict Contraindication: Never Dispense Topical Anesthetics

Topical anesthetics (proparacaine 0.5%, tetracaine 0.5%) rapidly relieve corneal pain, tempting clinicians to provide small dropper bottles for home use. THIS IS STRICTLY CONTRAINDICATED. Repeated outpatient administration inhibits corneal epithelial mitosis, causes microvilli loss, produces toxic keratopathy ('corneal melting'), and results in catastrophic corneal perforation and irreversible blindness. Control pain with oral NSAIDs and systemic analgesics.

2. Corneal Staining Patterns & Clinical Differentials

Fluorescein Staining Pattern	Microscopic/Slit-Lamp Finding	Diagnosis	Emergency Treatment
Linear/Geographic Defect	Circumscribed, bright green epithelial stain with clear surrounding corneal stroma and no white infiltrate	Simple Corneal Abrasion	Non-contact lens: Erythromycin 0.5% ointment QID x 3-5 days. Contact lens: Ciprofloxacin 0.3% drops. Oral NSAIDs. 24-48h follow-up.
Branching Dendritic Ulcer	Branching, linear arborizing pattern with classic terminal bulbs; reduced corneal sensation	Herpes Simplex Virus (HSV) Keratitis	Trifluridine 1% ophthalmic drops 8-9 times/day OR Ganciclovir 0.15% gel 5 times/day PLUS oral Valacyclovir 1000 mg TID. NEVER PRESCRIBE STEROIDS (causes rapid corneal perforation).
Punctate Superficial Keratitis (SPK)	Diffuse, bilateral punctate stippling across bilateral corneas ('sandpaper' appearance)	Ultraviolet/Welder's Flash Keratitis	Occurs 6-12 hours after UV exposure (arc welding, tanning bed, alpine snow). Cycloplegic drop (Cyclopentolate 1%) for ciliary spasm, Erythromycin ointment, cold compresses, dark glasses.
Dense White Corneal Infiltrate	Focal white/opaque stromal infiltrate underlying an epithelial defect with surrounding conjunctival ciliary flush	Corneal Ulcer (Bacterial Keratitis)	Bacterial emergency. High-frequency topical fortified antibiotics (Vancomycin + Tobramycin or Moxifloxacin drops every 1 hour around the clock). Urgent same-day ophthalmology consult.

3. Antimicrobial Selection: Contact Lens vs. Non-Contact Lens

Patient Cohort	High-Risk Pathogens	First-Line Ophthalmic Antibiotic Regimen	Patching Recommendation
Non-Contact Lens Wearer (Fingernail, paper cut, branch)	Staphylococcus aureus, Streptococcus pneumoniae	Erythromycin 0.5% ophthalmic ointment QID x 3-5 days (or Polymyxin B/Trimethoprim drops 1-2 drops QID)	DO NOT PATCH. Meta-analyses demonstrate eye patching does NOT reduce pain, delays corneal re-epithelialization, and impairs binocular vision.
Contact Lens Wearer (Sleeping in contacts, hot tub, tap water rinse)	PSEUDOMONAS AERUGINOSA (80%), Acanthamoeba	Ciprofloxacin 0.3% drops OR Ofloxacin 0.3% drops OR Tobramycin 0.3% drops: 1-2 drops every 2 hours while awake for 5-7 days	EYE PATCHING IS STRICTLY FORBIDDEN. Discontinue all lens use. Discard current lenses and case. Mandatory 24-hour ophthalmology follow-up.

4. Corneal Foreign Body & Rust Ring Removal

Anesthetize the Eye: Instill 1-2 drops of Proparacaine 0.5% into the conjunctival sac. Position patient securely at the slit lamp with forehead pressed firmly against the headrest band.
Superficial Foreign Body Extraction: First attempt gentle removal using a sterile saline-moistened cotton-tipped applicator. If adhered, use a sterile 25-gauge or 27-gauge needle held bevel-up tangential to the cornea (approaching from the side, never pointing toward the pupil) to flick the foreign object off the epithelial surface.
The Rust Ring Problem: Metallic iron foreign bodies oxidize rapidly in the moist tear film, depositing an orange-brown circular rust ring within 2-4 hours. A persistent rust ring causes chronic irritation, delayed healing, and corneal scarring.
Removal Technique & Timing: If a rust ring is peripheral and superficial, gently debride with an ophthalmic rotating burr (Algerbrush). If the rust ring is central (over visual axis) or deep in the stroma, DO NOT aggressively excavate. Prescribe prophylactic fluoroquinolone drops; the iron ring will oxidize, soften, and coalesce over 24-48 hours, allowing easy and safe unroofing by an ophthalmologist at follow-up.

5. Chemical Ocular Burns: Immediate Resuscitation Protocol

Chemical burns are the ONLY ocular emergency where treatment PRECEDES visual acuity assessment. Alkali injuries (ammonia, lye, drain cleaner, wet concrete) cause liquefaction necrosis, rapidly penetrating deep into the anterior chamber, whereas acids cause coagulation necrosis with protein precipitation creating a protective barrier:

Immediate Irrigation: Immediately instill 1 drop of proparacaine and place a Morgan lens connected to 1-2 Liters of normal saline or lactated Ringer's solution. Irrigate both eyes if bilateral exposure.
Sweep Fornices: Double-evert eyelids and sweep superior and inferior fornices with a moistened cotton swab to remove particulate matter (e.g., lime, drywall, powdered cement) that would continue to dissolve and burn.
Serial pH Monitoring: Stop irrigation after 2 liters. Wait 10 MINUTES to allow tear equilibrium. Touch pH litmus indicator paper to the inferior conjunctival cul-de-sac. Target pH is 7.0 to 7.4. If pH is < 7.0 or > 7.4, resume irrigation with another 1-2 Liters until neutral.
Assess Limbal Ischemia: Look for 'corneal blanching' (loss of normal limbal vascularity, appearing chalky white). Limbal ischemia indicates destruction of corneal limbal stem cells, conferring high risk of permanent blindness requiring emergent ophthalmologic surgery.

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