Central retinal artery occlusion

Background

  • Abbreviation: CRAO
  • The first branch of internal carotid artery is the ophthalmic artery
  • More common in the elderly with carotid artery disease
  • Restoration of blood flow within 100min may lead to complete recovery
    • Occlusion >240min leads to irreversible damage
  • 5-10% of CRAO is associated with giant cell arteritis[1]

Etiology

Clinical Features

Differential Diagnosis

Acute Vision Loss (Noninflamed)

Emergent Diagnosis

Evaluation

  • APD
  • Etiology work-up
    • ESR and CRP
    • Carotid US
    • ECG
    • Echo for embolus or atrial shunt
    • CBC, coags, ANA, syphilis

Fundoscopy

  • Pale retina, cherry red macula
  • Boxcar segmentation of blood column
  • Cherry red spot
    • Macula is thinnest portion of retina
    • Intact underlying choroidal circulation remains visible through this section
      • Macular area maintains normal color (red) versus surrounding ischemic, pale retina due to differing blood supplies

Management

Consult ophtho with goals for reducing itraocular pressure, dislodging the embolus or increasing arterial flow
Start high dose systemic corticosteroids if high ESR/CRP (especially high CRP) and sudden vision loss
  • Median starting PO prednisone 80mg/day, with 40% of patients on > 100mg/day
  • Treat until BOTH ESR and CRP stabilize (~2-3 wks)[2]

No evidence supporting or refuting the following treatments: [3]

  1. Ocular massage
    • Intermittent direct digital pressure applied through closed eyelid x 10-15 sec with rapid release to create pressure gradient to dislodge embolism
  2. Timolol ophthalmic 0.5% to decrease intraocular pressure
  3. Increase PCO2 leading to retinal artery vasodilation/increased retinal blood flow
    • Rebreathe into paper bag x10 min q hr
    • Inhale 95% O2 and 5% CO2 (Carbogen)[5]
  4. Anterior chamber paracentesis
    • Causes acute drop in IOP to dislodge embolism
  5. Intraarterial fibrinolysis or low dose systemic thrombolytics[6][7]
  6. Acetazolamide, 500mg IV or PO
  7. Mannitol

Disposition

  • Discharge with ophtho follow up in 1-4wk

See Also

References

  1. Miller N, Newman N. Walsh & Hoyt’s Clinical Neuro-ophthalmology. 5th Edition. Baltimore: Williams and Wilkins 1998. pp. 3758-9.
  2. Hayreh SS. Anterior Ischemic Optic Neuropathy. [Internet]. 2013 Available from: http://www.medicine.uiowa.edu/eye/AION-part2/.
  3. Rudkin A et al. Clinical characteristics and outcome of current standard management of central retinal artery occlusion. Clin Experiment Ophthalmol 2010; 38:496-501
  4. Gerstenblith BI, Fecarotta CM. The Wills Eye Manual. Lippincott 2012.
  5. Atebara N. Efficacy of anterior chamber paracentesis and carbogen in treating nonarteritic central retinal artery occlusion. Ophthalmology 1995; 102:2029-2038
  6. Schumacher M, et al: Central retinal artery occlusion: Local intraarterial fibrinolysis versus conservative treatment, a multicenter randomized trial. Ophthalmology 2010; 117:1367-1375
  7. Chen C et al: Efficacy of intravenous tissue-type plasminogen activator in central retinal artery occlusion: Report from a randomized, controlled trial. Stroke 2011; 42:2229-2234.

Authors:

Claire, Neil Young