Conjunctival foreign bodies are particles that enter the eye from the outside. They can include anything from metal fragments to organic particles.
The conjunctiva, being the first contact surface of the eye, is a suitable landing spot for particles that float in the air. It is therefore quite common for objects of all sizes and kinds to be lodged here, particularly under the eyelids. The foreign bodies are usually a source of discomfort but will rarely cause further problems.
In a few instances, the foreign object may be a cause for worry. Individuals should seek immediate professional attention if:
- Particle has sharp edges
- Enters at a high-speed rate
- Causes bleeding
- Large object that covers the eye
- Contains chemicals
- Penetrates the eye
Also Known As
Causes and Risk Factors
Foreign bodies land in the conjunctiva during normal day to day activities. However, certain events cause significant unsettlement of particles in the atmosphere. Where there’s wind, explosions or accidents, for instance, the risk of entry is high. The most common types of particles include:
- Metal fragments
- Glass shards
- Contact lenses
Signs & Symptoms
Patients with a conjunctival foreign body will usually complain of a foreign body sensation. The individual feels as if there’s grit or some sand in the eye.
Other symptoms may include:
- Red eye
- Excessive blinking
- Pain when looking at light
After presenting the symptoms, the eye professional should do a careful eye examination which includes:
- History of injury - In some events, previous injuries may cause the foreign body sensation. It is therefore imperative for the patient’s eye history to be taken to rule out eye trauma.
- Visual acuity test - Foreign bodies in the conjunctiva should not result in a significant decrease in visual acuity. In the case of this, further tests should be done to check for other ocular problems.
- Slit-lamp eye exam - The ideal ophthalmic exam used to diagnose for conjunctival foreign bodies is the slit lamp test. The device allows for proper detection of particles such as glass that may be difficult to see.
- Fluorescein staining - Staining is essential for diagnosing corneal abrasions due to the foreign body. The eye is viewed from an ophthalmoscope for scratches in the cornea.
- CT scan - Where the professional suspects penetration in the eye, imaging may be necessary.
Treatment is aimed at removing the foreign object. Usually, no surgical procedures are involved.
The eye doctor may administer topical anesthetic drops before proceeding to remove the particle. A damp cotton swab is then used to remove the object from the eye gently. Glass can be removed using forceps, blunt spatula or cotton-tipped applicator. It should automatically relieve symptoms in a few hours. If not, that may be an indication of a second foreign body or corneal abrasion.
For foreign bodies embedded in tissue, a sterile disposable hypodermic needle is used. An aesthetic may also be used in this case.
Saline irrigation is used for multiple small fragments where particles cannot be removed one by one. It also helps relieve symptoms of irritation, discomfort and itching.
In cases of corneal abrasion, doctors may give antibiotics to prevent infection.
For mild cases, the foreign particles can be removed immediately without professional intervention. Hands should be well washed before touching the eye to avoid infections. The affected individual should turn the eye up and down while another looks for the object using bright light.
For treatment, the affected side of the face can be immersed in a flat container with water or an eyecup. The individual should then open the eye and close to flush the object. For objects under the lower eyelid, one should evert the eyelid or press skin below to see underneath. If the particle is visible, a moistened cotton swab can be used to remove it. For children, a glass of warm water should be poured into the eye instead of immersing their faces.
In most cases, healing occurs within a day or two. Where there’s corneal abrasion, healing should take about three days. The patient should return to the doctor if the sensation recurs or if there’s pain or visual changes.
Entry of particles in the eyes may be difficult to avoid. However, wearing protective eyewear or safety glasses in environs with airborne objects aids in protecting the eyes.
Where there’s an intense high-speed impact, intraocular penetrations may occur. It can result in a discharge of fluid, bleeding or infections such as endophthalmitis. If the object damages the cornea or lens, damaged/lost vision can occur.