DIAGNOSIS
- Categorize visual loss by the properties associated with the decrease in visual function
- Transient (<24 hr):
- Minutes:
- Transient ischemic attack = amaurosis fugax (unilateral)
- Vertebrobasilar artery insufficiency (bilateral)
- Minutes to hours:
- Migraine
- Sudden BP changes
- Persistent (>24 hr):
- Painless: Sudden:
- Retinal artery or vein occlusion
- Vitreous hemorrhage
- Retinal detachment
- Optic neuritis
- Giant cell arteritis
- Cerebral infarct
- Painless: Gradual (weeks to years):
- Cataract
- Presbyopia
- Refraction errors
- Open-angle glaucoma
- Chronic retinal disease
- Macular degeneration
- Diabetic retinopathy
- CMV retinopathy
- CNS tumor
- Painful:
- Corneal abrasion, ulcer, burn, or foreign body
- Angle-closure glaucoma
- Optic neuritis
- Iritis/uveitis/endophthalmitis
- Keratoconus with hydrops
- Orbital cellulitis/abscess
- Monocular: Pathology anterior to optic chiasm
- Binocular: Pathology posterior to optic chiasm
- Associated with systemic neurologic symptoms of visual field defects:
- CVA (especially posterior or occipital circulation)
- Mass lesion (pituitary adenomas, aneurysm, meningioma, other tumors)
- Malingering/hysteria
SIGNS AND SYMPTOMS
History
- Decreased vision:
- Loss of vision
- Blurry vision
- Double vision:
- History of trauma
- Use of corrective lenses:
- Prior eye surgery or problems
- Eye pain
- Conjunctival redness or discharge
- New floaters
- Flashing lights
- Pain with eye movement
- Key elements to determine:
- Acute or gradual onset
- Length of symptoms
- Transient vision loss or permanent
- Binocular or monocular
- Degree of vision loss
- Painful or painless
- Other comorbidities
Physical-Exam
- Ophthalmologic:
- Visual acuity
- Pupil exam
- Afferent papillary defect
- Confrontational visual field exam
- Extraocular muscle function
- Slit-lamp exam
- Intraocular pressure (Tonometry)
- Fundoscopy:
- Optic nerve swelling
- Pale retina with a cherry-red spot
- Cardiovascular:
- Murmurs
- Carotid bruits
- Temporal artery tenderness
- Neurologic exam:
- Complete exam for other deficits
- Optic chiasm and intracerebral lesions
- Occipital and posterior circulation lesions
- General:
- Signs of immune, endocrine, or toxic disorders
ESSENTIAL WORKUP
Thorough history and physical exam
DIAGNOSIS TESTS & NTERPRETATION
Lab
- May be obtained to determine extent of other comorbidities in association with vision loss (i.e., diabetes, cardiovascular disease)
- Erythrocyte sedimentation rate if giant cell arteritis is suspected
Imaging
- Tests should be directed toward the suspected etiology of visual loss
- Dilated fundus exam may be performed to assess for posterior segment disease
- Temporal artery biopsy may be obtained if giant cell arteritis is suspected
- Brain CT, MRI, MRA, and transcranial Doppler may be used to evaluate neurologic symptoms and vertebrobasilar artery
- Urgent cardiac and carotid US if a retinal artery occlusion is diagnosed
- Facial CT may be used to evaluate extent of traumatic injuries
DIFFERENTIAL DIAGNOSIS
- Trauma
- Neurologic lesion
- Infectious
- Cardiovascular
- Toxic/metabolic
- Autoimmune
TREATMENT
PRE HOSPITAL
- Chemical burns:
- Begin copious irrigation with water or saline
ED TREATMENT/PROCEDURES
- Direct therapy toward cause of visual loss
- Ophthalmology consultation for visual loss with an uncertain diagnosis
- 3 conditions for which identification and treatment must begin within minutes:
- Central retinal artery occlusion
- Chemical burn
- Acute angle-closure glaucoma
Central Retinal Artery Occlusion
- Clinical criteria:
- Unilateral, painless, dramatic vision loss
- Afferent pupillary defect
- Pale fundus with a cherry-red spot (macula)
- Counting fingers to light perception in 94% of patients
- Therapy:
- Immediate ophthalmology consultation
- Maneuvers and medications to lower intraocular pressure, allowing the embolus to move to the periphery:
- Ocular massage: Direct pressure to eye for 5–15 sec then sudden release, repeat for 15 min
- Acetazolamide: 500 mg IV or PO
- Topical β-blocker
- Anterior chamber paracentesis by an ophthalmologist
- Referral for cardiac and carotid artery workup
- Rule out giant cell arteritis
Chemical Burn
- Clinical criteria:
- Alkali worse than acids
- White eye (vessels have already sloughed) worse than red eye (vessels are intact)
- Examples: Mace, cements, plasters, solvents
- Therapy:
- Topical anesthetic
- Copious irrigation of the eyes with LR or NS (nonsterile water is acceptable if others not available); minimum of 30 min
- Goal: Neutral pH at 5–10 min after ending irrigation
- Do not try to neutralize acids with alkalis or vice versa
- Evert lids and use moist cotton-tipped applicator to sweep furnaces for residual chemical precipitants
- Dilate with cycloplegic (atropine, cyclopentolate, tropicamide)
- Do not use phenylephrine; vasoconstricts already ischemic conjunctival blood vessels
- Erythromycin ointment q1–2h
- Artificial tears q1h
- Check intraocular pressure
Acute Angle-closure Glaucoma
- Signs and symptoms:
- Unilateral, painful vision loss
- Nausea, vomiting, headache
- Cornea injected, edematous
- Mid-dilated, sluggish/nonreactive pupil
- Swollen, “steamy” lens
- Cell, flare in a shallow anterior chamber
- Increased intraocular pressure (>20 mm Hg)
- Therapy:
- Topical β-blocker
- Topical prostaglandin analog
- Acetazolamide
- Topical α-2 agonist
- Pilocarpine
- Mannitol: If no decrease in IOP after 1 hr
MEDICATION
- Antibiotic drops:
- Ciprofloxacin 0.3%: 1–2 gtt q1–6h
- Gentamicin 0.3%: 1–2 gtt q4h
- Ofloxacin 0.3%: 1–2 gtt q1–6h
- Levofloxacin 0.5%: 1–2 gtt q2h
- Polymyxin (Polytrim) 1 gtt q3–6h
- Sulfacetamide 10%, 0.3%: 1–2 gtt q2–6h
- Tobramycin 0.3%: 1–2 gtt q1–4h
- Trifluridine 1%: 1 gtt q2–4h
- Antibiotic ointments:
- Bacitracin 500 U/g 1/2 in ribbon q3–6h
- Ciprofloxacin 0.3%: 1/2 in ribbon q6–q8h
- Erythromycin 0.5%: 1/2 in ribbon q3–6h
- Gentamicin 0.3%: 1/2 in ribbon q3–4h
- Neosporin 1/2 in ribbon q3–4h
- Polysporin 1/2in ribbon q3–4h
- Sulfacetamide 10%: 1/2 in ribbon q3–8h
- Tobramycin 0.3%: 1/2 in ribbon q3–4h
- Vidarabine 1/2 in ribbon 5 times per day
- Mydriatics and cycloplegics:
- Atropine 1%, 2%: 1–2 gtt/day to QID
- Cyclopentolate 0.5%, 1%, 2%: 1–2 gtt PRN
- Homatropine 2%: 1–2 gtt BID–TID
- Phenylephrine 0.12%, 2.5%, 10%: 1–2 gtt TID–QID
- Tropicamide 0.5%, 1%: 1–2 gtt PRN dilation
- Corticosteroid–antibiotic combination drops (with ophthalmology consultation):
- Prednisolone (Blephamide) 1–2 gtt q1–8h
- Hydrocortisone/neomycin/bacitracin/polymyxin B (Cortisporin) 1–2 gtt q3–4h
- Dexamethasone/neomycin/polymyxin B (Maxitrol) 1–2 gtt q1–8h
- Prednisolone/gentamicin (Pred-G) 1–2 gtt q1–8h
- Dexamethasone/tobramycin/chlorobutanol (TobraDex) 1–2 gtt q2–26h
- Glaucoma agents (always with ophthalmology consultation):
- α-2 agonists:
- Brimonidine 1% 1 gtt TID
- Apraclonidine 1% 1 gtt TID
- β-blocker:
- Betaxolol 0.25%, 0.5%: 1–2 gtt BID
- Carteolol 1%: 1 gtt BID
- Levobunolol 0.25%, 0.5%: 1 gtt QD–BID
- Carbonic anhydrase inhibitor:
- Acetazolamide 500 mg PO/IV QD–QID
- Miotic (parasympathomimetic):
- Pilocarpine 0.25%, 0.5%, 1%, 2%, 3%, 4%, 6%, 8%, 10%: 1–2 gtt TID–QID
- Osmotic agent:
- Mannitol 1–2 g/kg IV over 45 min
- Prostaglandin analog:
- Latanoprost 0.005%: 1 gtt QD
- Only if mechanical closure is ruled out:
- Timolol 0.25%, 0.5%: 1 gtt BID
FOLLOW-UP