From the Guidelines
Central retinal artery occlusion (CRAO) requires immediate management as it is an ophthalmic emergency, and treatment should begin with ocular massage and other interventions to restore retinal perfusion and address underlying causes. The management of CRAO involves a range of interventions aimed at dislodging the embolus, improving oxygen delivery to the retina, and preventing recurrence and involvement of the other eye. According to the American Heart Association, CRAO is a medical emergency that requires early recognition and triage to emergency medical attention 1.
Key Interventions
- Ocular massage: applying digital pressure to the globe for 5-15 seconds then releasing, repeated for 15-20 minutes to dislodge the embolus
- Positioning the patient supine with the affected eye elevated to reduce intraocular pressure
- Anterior chamber paracentesis to rapidly decrease intraocular pressure and potentially dislodge the embolus
- Intraocular pressure-lowering medications like topical timolol 0.5%, oral acetazolamide 500 mg, or intravenous mannitol 1-2 g/kg
- Carbogen therapy (95% oxygen, 5% carbon dioxide) via face mask for 10-15 minutes every hour for 24 hours to increase retinal oxygenation and induce vasodilation
- Hyperbaric oxygen therapy may be beneficial if started within 8-24 hours
- Thrombolytic therapy with tissue plasminogen activator (tPA) remains controversial but may be considered within 4.5 hours of symptom onset 1
Underlying Causes
It's essential to identify and address underlying causes such as:
- Carotid artery disease
- Cardiac emboli
- Giant cell arteritis to prevent recurrence and involvement of the other eye 1.
Systemic Evaluation
A systemic evaluation for carotid occlusive and thromboembolic disease is necessary, especially in patients over 50 years of age, and giant cell arteritis should be suspected and treated with urgent systemic corticosteroid therapy if diagnosed or likely 1.
Follow-up
Patients with greater ischemia require closer and more frequent follow-up, and panretinal photocoagulation (PRP) treatment is recommended for patients who develop iris or retinal neovascularization 1.
From the Research
Management of Central Retinal Artery Occlusion (CRAO)
The management of CRAO involves a combination of emergency treatments and comprehensive medical evaluations. Some of the key aspects of CRAO management include:
- Emergency treatment: This may include intravenous acetazolamide, digital ocular massage, and inhalation of 5% carbon dioxide -- 95% oxygen for ten minutes 2.
- Immediate ophthalmologic referral and consultation: This is required to assess the patient's condition and provide appropriate treatment 2.
- Comprehensive medical evaluation: This is necessary to exclude systemic vascular disease and identify any underlying risk factors for CRAO 2, 3, 4.
- Secondary prevention: This involves managing risk factors to prevent further vascular events, such as cerebral ischemia, myocardial infarction, and cardiovascular death 3, 4.
Treatment Options for CRAO
Various treatment options have been used for CRAO, including:
- Carbogen inhalation
- Acetazolamide infusion
- Ocular massage and paracentesis
- Vasodilators such as intravenous glyceryl trinitrate
- Thrombolytic therapy, delivered either intravenously or intra-arterially by direct catheterisation of the ophthalmic artery 3. However, none of these treatments have been shown to definitively alter the natural history of the disease 3.
Importance of Timely Treatment
Timely treatment is crucial for CRAO, with the best outcomes achieved when treatment is initiated within 6 hours of symptom onset 3, 5. Unfortunately, many patients experience delays in presentation and diagnosis, which can impact treatment outcomes 5. Public health educational campaigns and infrastructure optimization are needed to speed up presentation times and decrease the time to ophthalmic diagnosis, particularly for vulnerable populations 5.