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Red eye is a common but multifaceted condition with a wide range of potential causes. While many cases are benign and self-limiting, some require urgent medical intervention. A careful history and physical examination are key to identifying the underlying cause and determining the appropriate treatment. Recognizing the signs that necessitate emergency care can help prevent serious visual complications.
Red eye is a common ocular condition characterized by redness of the eye due to inflammation or irritation. It can be caused by a variety of factors, ranging from benign to serious conditions. Understanding the underlying causes and appropriate management strategies is crucial for effective treatment and prevention of complications.
Common Causes of Red Eye
Conjunctivitis
Conjunctivitis, also known as pink eye, is the most frequent cause of red eye. It can be viral, bacterial, or allergic in nature. Viral conjunctivitis, often caused by adenoviruses, is highly contagious and usually self-limiting. Bacterial conjunctivitis may require antibiotic treatment, while allergic conjunctivitis is typically managed with antihistamines and avoiding allergens1 3 4 5.
Blepharitis
Blepharitis is an inflammation of the eyelids that can lead to red eye. It is often associated with bacterial infections or skin conditions like seborrheic dermatitis. Treatment includes good eyelid hygiene and, in some cases, antibiotic or steroid eye drops1 6.
Corneal Abrasion and Foreign Bodies
Corneal abrasions and foreign bodies in the eye can cause significant redness and discomfort. These conditions often result from trauma or exposure to irritants. Immediate removal of the foreign body and appropriate wound care are essential to prevent infection and promote healing1 2 5.
Subconjunctival Hemorrhage
A subconjunctival hemorrhage occurs when a small blood vessel breaks just beneath the surface of the eye, leading to a bright red patch. This condition is usually harmless and resolves on its own without treatment1 2.
Keratitis and Iritis
Keratitis, an inflammation of the cornea, and iritis, an inflammation of the iris, are more serious causes of red eye. These conditions can result from infections, autoimmune diseases, or trauma and often require prompt medical attention to prevent vision loss1 2 6.
Glaucoma
Acute angle-closure glaucoma is a medical emergency characterized by a sudden increase in intraocular pressure, leading to red eye, severe pain, and vision loss. Immediate treatment is necessary to prevent permanent damage to the optic nerve1 2 7.
Diagnosis and Management
History and Physical Examination
A thorough patient history and physical examination are crucial for diagnosing the cause of red eye. Key aspects to consider include the onset and duration of symptoms, presence of pain, discharge, visual changes, and any history of trauma or exposure to irritants1 4 8.
Treatment
Treatment of red eye depends on the underlying cause. For most cases of conjunctivitis, supportive care with artificial tears and warm compresses is sufficient. Bacterial infections may require antibiotics, while allergic reactions can be managed with antihistamines. More serious conditions like keratitis, iritis, and glaucoma necessitate urgent referral to an ophthalmologist for specialized care1 2 9 10.
When to Seek Emergency Care
Certain symptoms associated with red eye warrant immediate medical attention. These include severe pain, significant photophobia, decreased vision, and a history of ocular trauma. Prompt evaluation by an ophthalmologist is essential to prevent complications and preserve vision1 2 9.