Basics
Description
- Obstruction of the central retinal artery associated with sudden painless loss of vision
- Usually occurs in persons 50-70 yr of age
- Ophthalmic artery is 1st branch of carotid.
- Risk factors include HTN, atherosclerotic disease, sickle cell disease, vasculitis, valvular heart disease, lupus, trauma, and coronary artery disease.
- Incidence of 1-10/100,000
- Often described as a "stroke of the eye"�
Etiology
- Embolic:
- Occlusion by intravascular material from a proximal source:
- Atherosclerotic disease (majority)
- Carotid artery stenosis
- Valvular heart disease (cardiogenic emboli)
- Atrial myxoma
- Dissection of the ophthalmic artery
- Carotid artery dissection
- Thrombotic:
- Obstruction of flow from the rupture of a pre-existing intravascular atherosclerotic plaque
- Hypercoagulable states (sickle cell)
- Inflammatory:
- Due to temporal arteritis, lupus, vasculitis
- Arterial spasm:
- Associated with migraine headaches
- Decreased perfusion:
- Low-flow conditions such as in severe hypotension or high-pressure situations seen in acute angle-closure glaucoma or retrobulbar hemorrhage
Diagnosis
Signs and Symptoms
History
- Sudden, painless, monocular loss of vision
- Prior episodes of sudden visual loss:
- May last a few seconds to minutes (amaurosis fugax)
- Caused by transient embolic phenomena or decreased ocular blood flow
Physical Exam
- Significantly decreased visual acuity
- Afferent pupillary defect usually present
- Retinal appearance:
- Emboli visualized within vascular tree of the retina
- Appears as glinting white or yellow flecks (Hollenhorst plaques) within the vessels
- Ischemic edema visible within 15-20 min of occlusion
- "Cherry-red spot"� remains over the fovea (only area where there is very thin retina allowing the vascular choroids to show through).
- Affected arteries empty or showing dark red stationary or barely pulsatile segmented rouleaux ("box-carring"�)
- Within 1-2 hr opacification of the usually transparent infarcting retinal nerve layer occurs.
- Partial field deficits:
- Occur only if branch of central retinal artery involved
Essential Workup
- Visual acuity and visual field testing
- Fundoscopic exam
- Intraocular pressure measurements
- Emergent ophthalmologic consultation
Diagnosis Tests & Interpretation
Lab
Directed toward evaluating underlying etiology of occlusion: �
- CBC with differential and platelet count
- PT/PTT
- Electrolytes, BUN/creatinine, glucose
- Electronic spin resonance for giant cell arteritis (in patients >55 yr old)
- ANA, RF, CRP, ESR
- Rapid plasma reagin (RPR)
- Hemoglobin electrophoresis
- Serum protein electrophoresis
Imaging
Directed toward evaluating underlying etiology of occlusion: �
- Carotid artery ultrasound/Doppler
- Possibly echocardiography
- Fluorescein angiography or electroretinography to confirm the diagnosis
Differential Diagnosis
- Acute angle-closure glaucoma
- Central retinal vein occlusion
- Giant cell arteritis (temporal arteritis)
- Optic neuritis
- Retinal detachment
Treatment
Initiate treatment immediately because irreversible visual loss occurs at 90 min: �
- Only immediate treatment may help to salvage or restore sight to the affected eye.
- Goals of therapy include dislodging or dissolving the embolus, arterial dilation to improve forward flow, and reduction of intraocular pressure to improve the perfusion gradient.
Ed Treatment/Procedures
- Immediate global massage in an attempt to dislodge the embolus:
- Lay patient flat and apply digital global massage bolus.
- On closed eyelid, apply constant pressure for 15 sec and remove for 15 sec. Repeat for 5 cycles.
- Initiate high-flow oxygen via 100% nonrebreather:
- Consider transfer to a facility capable of providing hyperbaric oxygen (HBO) if <24 hr from symptom onset
- May use inhaled carbogen (a mixture of carbon dioxide and oxygen gas) if available
- Administer IV acetazolamide to decrease intraocular pressure.
- Apply topical timolol maleate to reduce intraocular pressure.
- Administer aspirin and IV heparin for prevention of clot propagation.
- Obtain emergent ophthalmology consultation for:
- Anterior chamber paracentesis to help reduce intraocular pressure
- Possible intra-arterial fibrinolysis for clot lysis
- Administer high-dose systemic steroids in suspected cases of inflammatory arteritis.
Medication
First Line
- Acetazolamide: 500 mg IV or PO
- Carbogen: Inhalation of 95% oxygen and 5% carbon dioxide mixture
- Heparin: 80 U/kg IV bolus then 18 U/kg/h continuous infusions (rate adjusted based on PTT level)
- Timolol maleate 0.5% solution: 1 drop topically to affected eye
Second Line
- Methylprednisolone: 250 mg IV in suspected cases of inflammatory arteritis
- Aspirin: 325 mg PO
- Mannitol
- Sublingual nitroglycerin
Follow-Up
Disposition
Admission Criteria
Required for workup of proximal cause in acute cases (source of embolism, thrombosis, or inflammatory) �
Discharge Criteria
Chronic retinal artery occlusion with no evidence of active disease can be worked up as an outpatient. �
Issues for Referral
All suspected cases warrant emergent ophthalmology consultation. �
Followup Recommendations
Most cases will require carotid ultrasound to exclude atherosclerotic disease. �
Pearls and Pitfalls
- Amaurosis fugax (transient, possibly resolved retinal artery occlusion) is a sentinel event and may lead to complete occlusion or stroke. Do not ignore these symptoms and urgent workup is required.
- Retinal artery occlusion is a medical emergency requiring immediate treatment to prevent loss of the eye.
- It is important to document a full eye exam including visual acuity and evaluation of the optic fundus.
Additional Reading
- Arnold �M, Koerner �U, Remonda �L, et al. Comparison of intra-arterial thrombolysis with conventional treatment in patients with acute central retinal artery occlusion. J Neurol Neurosurg Psychiatry. 2005;76(2):196-199.
- Fraser �SG, Adams �W. Interventions for acute non-arteritic central retinal artery occlusion. Cochrane Database Syst Rev. 2009;(1):CD001989.
- Hazin �R, Daoud �YJ, Khan �F. Ocular ischemic syndrome: Recent trends in medical management. Curr Opin Ophthalmol. 2009;20:430-433.
- Murphy-Lavoie �H, Butler �F, Hagan �C. Central retinal artery occlusion treated with oxygen: a literature review and treatment algorithm. Undersea Hyperb Med. 2012;39(5):943-953.
- Vortmann �M, Schneider �JL. Acute monocular visual loss. Emerg Med Clin North Am. 2008;26(1):73-96.
See Also (Topic, Algorithm, Electronic Media Element)
- Central Retinal Venous Occlusion
- Visual Loss
Codes
ICD9
362.31 Central retinal artery occlusion �
ICD10
- H34.10 Central retinal artery occlusion, unspecified eye
- H34.11 Central retinal artery occlusion, right eye
- H34.12 Central retinal artery occlusion, left eye
- H34.13 Central retinal artery occlusion, bilateral
- H34.1 Central retinal artery occlusion
SNOMED
- 38742007 Central retinal artery occlusion