OCULAR SYMPTOMS 

The Sensation that something is in the Eye

Contents of this Page

Introduction: "Foreign body sensation"

The sensation that something is in the eye commonly brings people to the ophthalmologist. This is referred to as a "foreign body sensation", as if a foreign object were scratching the eye. Usually this sensation originates from the cornea, which is the clear part of the eye through which we see. The cornea has a huge number of nerve fibres that are normally covered by a lining. If this lining is breached, the sensation that something is in the eye results, whether or not anything is actually there. Any condition which can cause a scratch on the cornea can lead to this symptom. Some causes are detailed on this page. There are also links to other Symptom and Diagnosis pages based on other symptoms in addition to the foreign body sensation.

Conditions:

For eye anatomy explanations, go to ANATOMY

Dry eye

"Dry eye" is a common ocular problem, as is evidenced by the large number of artificial tear preparations available over-the-counter. There may be a tendency for tear production to decrease with aging, and dry eye problems may be associated with certain arthritis syndromes, such as Sjogren's syndrome and rheumatoid arthritis. However, many people can develop a problem with ocular dryness with no apparent underlying cause. Symptoms of dry eye include a sensation of dryness or grittiness, foreign body sensation, burning, redness, and generalized eye fatigue. The vision may blur or fluctuate. The eyes may seem sensitive to changes in temperature and to wind. Paradoxically, tearing may be a symptom of ocular dryness. Tearing can occur because the gland that produces tears in large quantities is not usually involved much in the minute to minute lubrication of the eyes. If the eye reach a certain extreme of dryness, this large tear gland becomes activated and produces excessive tears.

Symptoms of dry eye can have other causes than just reduced tear production. Oil producing glands in the eyelids provide a layer of oil on the surface of the eye which helps to prevent tears from evaporating. If this oil layer is deficient, as in certain types of blepharitis, the eyes can become dry much too quickly. Similarly, mucous helps to lubricate the eye, and if this is deficient, dry eye symptoms can result. Oral antihistamines may dry the eyes in this way. The ophthalmologist can determine the principle cause of the dryness symptoms, and direct therapy in the right direction.

Supplemental lubrication of the eye is the main treatment for dry eye. There are numerous artificial tears available. Generally, preservative free eyedrops are recommended in people who have to use eyedrops frequently and on a daily basis. Some preparations, such as Celluvisc and Refresh Plus, are thicker than most other artificial tears, and may provide more long lasting relief in some cases. Lubricant ointments are also available (such as Refresh P.M.). These are generally used at bedtime (since the vision is extremely blurred for a period of time after their use), but may give substantial relief.

Other options for treating dry eye include treating any other problems, such as blepharitis. Sometimes oral antibiotics may help. In severe cases, occlusion of the tear drainage system may help the tears to stay longer on the eye itself. There is no cure for dry eye itself at this point, only supportive therapy.

Corneal abrasion (scratched eye)

A corneal abrasion is a break in the surface layer of the cornea, which is the clear part of the eye through which we see. This usually follows obvious trauma, although an abrasion may occur from other causes, such as an in turned eyelash or from an eyelid infection (blepharitis). Symptoms include pain, redness, tearing, sensitivity to light, and blurred vision. The "foreign body" sensation can be severe, and often people describe symptoms of a "rock were rolling around under the eyelid". What is being felt is this extremely sensitive exposed part of the cornea.

Diagnosis and treatment should be made by an ophthalmologist. If trauma is involved, the eye must be thoroughly examined to rule out and other injury. Treatment is usually by patching of the eye with antibiotic ointment, or frequent use of antibiotic ointment or lubricating medication. There is risk of infection (corneal ulcer) and internal ocular inflammation (iritis) with this condition. Fortunately, under good circumstances, the cornea can heal rapidly, sometimes even overnight.

Inturned eyelash (trichiasis)

Trichisis refers to misdirected eyelashes, where they point backwards and irritate the eye surface. Symptoms are usually of a foreign body sensation, but more severe symptoms of redness, pain, tearing, and light sensitivity are not uncommon. Treatment is by removing the offending eyelash (epilation), and by providing protective treatment for any corneal injury which may have occurred. With recurrent in turned eyelashes, electrolysis may permanently remove the eyelash, although more than one treatment may be necessary.

Corneal foreign body

A foreign material can lodge itself onto the cornea and cause significant symptoms of pain, tearing, light sensitivity, and blurred vision. Except in cases of obvious trauma where debris strikes the eyes, the most common corneal foreign body is a rusted metallic particle. Small shards of metal seem to have an almost magnetic attraction to the corneal surface, where they rapidly rust and become embedded. The use of saftey goggles with any type of drilling, hammering, etc. can be preventative. As the rusted particle sits on the cornea, the eye becomes progressively more irritated over a period of days with redness, pain, light sensitivity, and tearing. Often the particle is visible on the eye, but it may be nearly microscopic. The ophthalmologist has the equipment necessary in the office to remove these foreign bodies. Usually a scar remains, and there is risk of infection.

Foreign body under eyelid

Debris which gets into the eyes can become trapped under the upper eyelid. This will lead to worsening symptoms of foreign body sensation, pain, tearing, and redness. The debris can be nearly anything, and plant material (wood) is not uncommon. A large foreign body under the lid rapidly becomes intolerable, with a corneal scratch occurring every time the eye blinks. Obviously, removal of the foreign body is curative.

Recurrent corneal erosion (spontaneous)

After the cornea is scratched, it can heal superficially very rapidly to cover the defect. However, a longer period of time (months) is required for this area of healing to become firmly bonded in place. In some people, an area of corneal injury may be permanently weakened. In this situation, minimal trauma to the eye may be enough to cause this area of weakening to slough off, leading to a corneal abrasion again. This "minimal trauma" can include things as simple as eye rubbing or the eye opening for the first time in the morning.

This second situation is the most common. Typically, people with a recurrent corneal erosion problem experience ocular pain upon awakening. The eye may tear and have foreign body sensation. The corneal defect rapidly heals over in most cases, and the symptoms resolve in minutes to hours. However, the process may repeat itself the next morning. Some people may have an underlying weakness of the cornea (map-dot-fingerprint dystrophy), and can develop these symptoms with no history of trauma in the past.

Treatment is first to diagnose the problem, and then initially to try using lubricating ointments on the eye at bedtime. Sometimes these have to be used for weeks to months. Commonly used lubricants include Refresh P.M. and Muro 128. These lubricants help to prevent the eyelid from pulling open the corneal scratch upon awakening in the morning. In cases where the problem continues in spite of treatment, there are procedures which can be done in the ophthalmologist's office to reinforce the weakened area.

Other Conditions causing a foreign body sensation of the eye found on other pages: