H34.10 Central retinal artery occlusion, unspecified eye

Name of the Condition

• Central Retinal Artery Occlusion, Unspecified Eye

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. The condition 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 one eye
• 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 the affected eye

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 circulation and structure. Additional tests may evaluate underlying systemic conditions.

Treatment Options

Treatment focuses on managing the underlying cause and preserving vision. Immediate interventions may include ocular massage, medications to lower intraocular pressure, or systemic therapies to dissolve clots. Long-term management addresses risk factors like blood pressure and cholesterol control.

Prognosis and Follow-Up

The prognosis depends on the duration of the blockage and the extent of retinal damage. Early treatment improves outcomes, but permanent vision loss may occur. Follow-up includes regular eye examinations and monitoring for complications like neovascularization.

Complications

• Permanent vision loss
• Retinal ischemia
• Neovascularization (e.g., iris or retinal neovascularization)
• Secondary glaucoma

Lifestyle & Prevention

• Manage hypertension and diabetes
• Quit smoking
• Control cholesterol levels
• Maintain a healthy diet and exercise routine
• Regular cardiovascular check-ups

When to Seek Professional Help

Seek immediate medical attention for sudden, painless vision loss in one eye, as prompt treatment may reduce the risk of permanent damage.

Tips for Medical Coders

Use H34.10 for unspecified eye involvement. Document the affected eye (e.g., right/left/unspecified) and any associated symptoms or complications. Ensure clinical documentation supports the diagnosis and aligns with the unspecified eye designation.