H34.13 Central retinal artery occlusion, bilateral

Name of the Condition

• Central Retinal Artery Occlusion, Bilateral

Summary

Central retinal artery occlusion (CRAO) is a blockage of the central retinal artery, which supplies blood to the retina. This blockage disrupts blood flow and can lead to sudden, painless vision loss in the affected eye. When bilateral, the condition involves both eyes and is a medical emergency due to the risk of permanent retinal damage and vision impairment.

Causes

CRAO is typically caused by an embolus (e.g., from atherosclerotic plaque or cardiac sources) or thrombus blocking the central retinal artery. Other contributing factors may include vasospasm, inflammatory conditions, or trauma to the artery.

Risk Factors

• Advanced age
• Hypertension
• Atherosclerosis
• Cardiovascular disease
• Diabetes mellitus
• High cholesterol
• Smoking
• Hypercoagulable states
• Carotid artery disease

Symptoms

• Sudden, painless vision loss in both eyes
• Reduced visual acuity (e.g., "blacking out" or "fogging" of vision)
• Visual field defects (e.g., altitudinal or sectoral loss)
• Relative afferent pupillary defect (RAPD) in both eyes

Diagnosis

Diagnosis involves a comprehensive eye examination, including visual acuity testing, dilated funduscopy (to assess retinal whitening, cherry-red spot, or arterial narrowing), and imaging studies such as fluorescein angiography or optical coherence tomography (OCT) to evaluate retinal perfusion and structural changes.

Treatment Options

Treatment aims to restore blood flow and minimize retinal damage. Options may include ocular massage, anterior chamber paracentesis, or systemic therapies (e.g., thrombolytics, vasodilators). Management of underlying conditions (e.g., hypertension, diabetes) is also critical.

Prognosis and Follow-Up

Prognosis depends on the duration and severity of the occlusion. Early intervention improves outcomes, but permanent vision loss may occur. Follow-up includes regular eye examinations to monitor for complications and adjust management of systemic risk factors.

Complications

• Permanent vision loss
• Retinal ischemia or infarction
• Neovascularization (e.g., rubeosis iridis)
• Secondary glaucoma

Lifestyle & Prevention

• Control hypertension, diabetes, and cholesterol
• Avoid smoking
• Manage cardiovascular disease
• Seek prompt care for transient visual symptoms

When to Seek Professional Help

Seek immediate medical attention for sudden, painless vision loss in one or both eyes, as timely intervention may preserve vision.

Tips for Medical Coders

Use H34.13 for bilateral central retinal artery occlusion. Document laterality (bilateral) and any associated systemic conditions (e.g., hypertension, diabetes) to support coding accuracy. Ensure clinical documentation specifies the bilateral nature of the occlusion.