Why Do Eyes Become Red?

Reasons for Red Eyes and Corresponding Treatments

Many Asians have black eyes with a clear distinction between the iris and the sclera. Any abnormal change in iris color is highly noticeable. In daily life, many people find their eyes turning red, which may indicate an abnormality. Various factors can lead to this condition, and it's crucial to identify the cause promptly and take appropriate measures. Let's explore the reasons behind red eyes and their treatments.

1. Acute Conjunctivitis

Cause: A common contagious eye disease caused by bacterial or viral infections. It is highly infectious.

Symptoms: Sudden onset, affecting both eyes simultaneously or sequentially. The affected eye may experience stinging, itching, and a foreign body sensation. Severe cases may involve photophobia and a burning sensation, but vision is generally unaffected. Symptoms include swollen eyelids, conjunctival hyperemia, and bacterial, mucous, or purulent discharge. In the morning, the eyes may be sealed shut by discharge. Viral infections often produce watery discharge and may be accompanied by corneal lesions, swollen lymph nodes in front of the ears and under the jaw, and tenderness.

Treatment: Due to its contagious nature, prevention and isolation are crucial. Avoid sharing towels and handkerchiefs, and thoroughly clean and disinfect facebasins after use. Keep the eyes clean, rinsing with water when there is excess discharge. Topical antibiotics and antiviral drugs may be prescribed. If accompanied by systemic symptoms like fever and headache, internal medicine treatment should be considered.

2. Acute Iritis and Ciliary Body Inflammation

Cause: The etiology is complex, with most cases having unknown causes. It may be associated with autoimmune diseases such as rheumatism, tuberculosis, syphilis, and viral infections.

Symptoms: Ciliary congestion or mixed congestion, keratic precipitates (KP), cloudy aqueous humor, swollen iris, miotic or irregular pupil, sluggish light reflex, and posterior synechiae (adhesion between the iris and lens). Intraocular pressure is usually normal but may fluctuate. Vision loss is accompanied by photophobia, tearing, and pain that may radiate to the eyebrow arch, temple, and forehead.

Treatment: Actively seek the underlying cause and treat it accordingly. Topical 1% atropine eye drops for mydriasis, warm compresses, topical or subconjunctival injections of steroids, and systemic steroids or anti-inflammatory drugs for severe cases.

3. Keratitis

Cause: Most keratitis cases are caused by external infections. Minor corneal trauma often serves as a predisposing factor, with common pathogens including bacteria, fungi, and viruses. Corneal immune dysfunction or malnutrition can also lead to keratitis.

Symptoms: Eye pain, foreign body sensation, eyelid spasms, photophobia, tearing, and sudden vision loss. The specific symptoms vary depending on the cause but generally include eyelid spasms and edema, conjunctival hyperemia, mixed conjunctival hyperemia with edema, corneal opacity or ulceration, keratic precipitates, and hypopyon in the anterior chamber.

Treatment: Identifying and removing the underlying cause is crucial. For infectious keratitis, appropriate antibiotics or antiviral drugs are essential. Diagnosis can be confirmed through clinical features, smear and culture of secretions or ulcer tissue, and drug sensitivity tests. Treatment options include topical or subconjunctival injections of antibiotics or antivirals, and 1% atropine eye drops for mydriasis and pain relief.

4. Acute Angle-Closure Glaucoma

Cause: The etiology is complex, affecting women two to four times more frequently than men, particularly middle-aged and elderly women. It is a bilateral disease with a genetic component. It occurs due to the closure of the anterior chamber angle, impeding aqueous humor drainage and leading to elevated intraocular pressure.

Symptoms: Swollen eyelids and conjunctiva, cloudy corneal edema, shallow anterior chamber, swollen iris, dilated pupil with absent light reflex, and very high intraocular pressure (>60mmHg). Sudden vision loss, severe eye pain, ipsilateral migraine, nausea, and vomiting (easily misdiagnosed as gastrointestinal disease).

Treatment: Acute angle-closure