What Is the Conjunctiva?
The conjunctiva, also known as the conjunctival membrane, is a delicate and transparent tissue that covers the sclera (the white part of the eye) and lines the inside of the eyelids. Think of the conjunctiva as a saran-wrap like layer that covers the white part of the eye. This thin layer serves as a protective barrier for the eye, helping to keep it moisturized and shielded from external irritants. It plays a vital role in maintaining the health and proper functioning of the eye.
The conjunctiva is responsible for creating the mucus layer that plays a crucial role in the formation of your tears. The mucus combines with a watery liquid made by the lacrimal glands and oil from meibomian glands to create tears. Tears help to lubricate, retain moisture, and protect your eyes from particles, ensuring their optimal health and function. A healthy tear layer is crucial for clear vision.
The conjunctiva is made of three parts:
- Palpebral conjunctiva: This part lines the eyelids.
- Bulbar conjunctiva: This part covers the eyeball and protects the white of the eye.
- Conjunctiva fornix: This part joins the palpebral and bulbar conjunctiva.
What Is Pink Eye?
Pink eye, also called conjunctivitis, occurs when the conjunctiva becomes inflamed, either due to a virus (viral conjunctivitis), bacteria (bacterial conjunctivitis) or allergens (allergic conjunctivitis).
The inflammation associated with pink eye typically produces redness, excessive tears, and a gritty feeling or itchiness. Viral or bacterial conjunctivitis usually produces a discharge as well. The discharge in viral conjunctivitis is usually clear and tear-like, while the discharge in bacterial conjunctivitis is thicker and mucous-like. In other cases, it may produce discharge or cause a gritty feeling in the eye.
Pink eye is usually a mild eye condition that resolves on its own, although bacterial conjunctivitis can be treated with antibiotic drops and allergic conjunctivitis can often be relieved with allergy drops (either antihistamine or mast cell stabilizers). You should always seek advice from an eye doctor for a proper diagnosis and treatment. Some medications may not improve a given type of conjunctivitis, and, of even more concern, some medications may worsen conjunctivitis if used incorrectly or inappropriately.
What Other Conditions Can Cause These Symptoms?
Blepharitis: Blepharitis is an inflammation of the edges of the eyelids. Common symptoms include red, itchy, irritated eyelids caused by clogged oil glands at the base of the eyelashes. The skin becomes dry and flakey creating a crust along the eyelids. Eyes can feel dry and gritty. Depending on the underlying cause, blepharitis can sometimes be treated with antibiotics or steroids.
Contact lens infections: Eye infections can be common in people who do not handle contact lenses properly. For example, wearing dirty lenses or failing to wash your hands before placing contacts in your eye can transfer pathogens to the eye and can cause bacterial keratitis. An antibiotic is needed to treat bacterial infections.
Corneal abrasion: Trauma to the eye in the form of a scratched cornea can cause redness, pain, and discharge. Your eye doctor can determine the best course of action to treat a corneal abrasion, which may include antibiotic and/or steroid eye drops.
Dacryocystitis: Dacryocystitis occurs when the lacrimal glands become blocked and inflamed. When tears cannot drain properly, swelling can occur, especially in the inside corner of the eye, and can lead to an infection. In addition to swelling, this inflammation can cause tearing, discharge, redness, and pain. Dacryocystitis caused by a bacterial infection can be treated with antibiotics.
Dry eye syndrome: This common eye condition occurs either due to insufficient tear production or poor tear quality. When the eyes are dry and not sufficiently lubricated, redness, irritation, discomfort, and watery eyes can occur. Artificial tears or prescription eye drops can help treat dry eye syndrome.
Episcleritis: Episcleritis is inflammation of the episclera (thin layer between the conjunctiva and the white of the eye). Redness and eye discomfort are the two most common symptoms. Lubricating eye drops and topical steroids can treat episcleritis.
Eye strain: Staring at a phone, tablet, or computer for an extended period of time can dry the eyes out due to inadequate blinking to replenish tear film. Dryness, redness, and irritation can occur. Limiting screen time and blinking more often are the two simplest ways to treat digital eye strain.
Foreign body: This refers to any object or substance that enters and remains in the eye. Examples include an eyelash, a spec of dirt, chemicals, or metal shavings. The eye responds by becoming inflamed and producing excessive tears. Flushing the eye helps remove any particles, and an antibiotic may be prescribed to prevent an infection
Iritis or uveitis: These conditions occur when the iris (colored part of the eye that surrounds the pupil) or uvea (the middle of the eye) becomes inflamed. Symptoms include redness, pain and blurry vision. If the cause is an infection, antibiotics or antiviral can be prescribed. Steroid eye drops can also be used to treat these conditions.
Keratitis: Keratitis is inflammation or irritation of the cornea (the clear layer in front of the iris and pupil) that causes an open sore called a corneal ulcer. The ulcer can make your eyes water, cause redness, produce discharge or pus, or cause pain. Similar to conjunctivitis, a bacterial or viral infection can cause keratitis. When an infection is involved, keratitis is treated with antibiotic, antiviral, or antifungal eye drops. Artificial tears can treat non-infectious keratitis.
Pinguecula: Pinguecula is a yellowish growth that appears on the conjunctiva and usually grows on the eye near the nose. It can cause redness, irritation and discomfort. Excessive UV light exposure or dry, dusty environmental conditions are considered the most likely causes of pinguecula. Lubricating and/or steroid eye drops can help alleviate symptoms.
Pterygium: Pterygium is an abnormal growth of tissue on the conjunctiva that presents as a raised pink, white, or red lesion. Redness, irritation, and a gritty feeling may also occur. Lubricating eye drops can help soothe dryness and irritation, while steroid eye drops can reduce swelling. Pterygium can grow, and if it extends to the cornea, it can affect your vision. In such cases, surgery may be required to remove it.
