Introduction
Background
Corneal foreign body is foreign material on or in the cornea, usually metal, glass, or organic material.
Pathophysiology
Corneal foreign bodies generally fall under the category of minor ocular trauma. Small particles may become lodged in the corneal epithelium or stroma, particularly when projected toward the eye with considerable force.
The foreign object may set off an inflammatory cascade, resulting in dilation of the surrounding vessels and subsequent edema of the lids, conjunctiva, and cornea. White blood cells also may be liberated, resulting in an anterior chamber reaction and/or corneal infiltration. If not removed, a foreign body can cause infection and/or tissue necrosis.
Frequency
United States
Foreign bodies are one of the most frequent causes of visits for ophthalmic emergencies. Sometimes, the foreign body may not be present at the time of examination, having left the residual corneal abrasion with resultant pain.
Superficial corneal foreign bodies are much more common than deeply embedded corneal foreign bodies. The possibility of an intraocular foreign body must always be considered when a patient presents with a history of trauma.
In major league baseball, 33% of all eye injuries are corneal abrasions; in the National Basketball Association, corneal abrasions account for 12% of all eye traumas.
International
No difference in frequency is observed internationally.
Mortality/Morbidity
Generally, superficial foreign bodies that are removed soon after the injury leave no permanent sequelae. However, corneal scarring or infection may occur. The longer the time interval between the injury and treatment, the greater the likelihood of complications.
If the foreign body fully penetrates into the anterior or posterior chambers, then it is officially an intraocular foreign body. In this case, eye morbidity is much more common. Damage to the iris, lens, and retina can occur and severely damage vision. Any intraocular foreign body can lead to infection and endophthalmitis, a serious condition possibly leading to loss of the eye.
Sex
Similar to other traumatic injuries, the incidence in males is much higher than in females.
Age
Similar to most other traumatic injuries, the peak incidence is found in the second decade and generally occurs in people younger than 40 years.
Clinical
History
The activities of the patient and their surroundings are important. The time and the place of the injury, along with exactly how it occurred, are important. For example, a patient who was working with a high-speed grinding machine is likely to have an intraocular foreign body that may be occult in nature, whereas a patient who was working underneath a car when rust fell gently on the eye is likely to have only an external injury.
- Patients may complain of the following:
- Pain (typically relieved significantly with topical anesthesia)
- Foreign body sensation (typically relieved significantly with topical anesthesia)
- Photophobia
- Tearing
- Red eye
Physical
- Patients may present with the following:
- Normal or decreased visual acuity
- Conjunctival injection
- Ciliary injection, especially if an anterior chamber reaction occurs
- Visible foreign body
- Rust ring, especially if a metallic foreign body has been embedded for hours to days
- Epithelial defect that stains with fluorescein
- Corneal edema
- Anterior chamber cell/flare
- The patients may be asymptomatic if the foreign body is below the epithelial or conjunctival surface. Over a period of a few days, epithelium often grows over small corneal foreign bodies, with a resultant reduction in pain.
- If a corneal infiltrate is present, an infectious cause needs to be considered. Foreign bodies can cause a small sterile inflammatory reaction around the foreign object. However, if a large infiltrate, any corneal ulceration, a significant anterior chamber reaction, or significant pain is present, it should be managed as an infection. See Keratitis, Bacterial.
Causes
Corneal foreign body injury can occur just about anywhere. They commonly occur both at home and at work.
- Generally, the cause is accidental trauma. The type of trauma helps to determine the likelihood of a superficial versus a deep or even intraocular foreign body.
- Materials include small pieces of wood, metal, plastic, or sand.
- The injury usually occurs in windy weather or when working with power tools. Dirt, sand, or small portions of leaves frequently are blown into the eye and adhere to the superficial cornea.
More on Corneal Foreign Body |
 Overview: Corneal Foreign Body |
| Differential Diagnoses & Workup: Corneal Foreign Body |
| Treatment & Medication: Corneal Foreign Body |
| Follow-up: Corneal Foreign Body |
| References |
| Next Page » |
References
Peate WF. Work-related eye injuries and illnesses. Am Fam Physician. Apr 1 2007;75(7):1017-22. [Medline].
Carley F, Carley S. Towards evidence based emergency medicine: best BETs from the Manchester Royal Infirmary. Mydriatics in corneal abrasion. Emerg Med J. Jul 2001;18(4):273. [Medline].
Arbour JD, Brunette I, Boisjoly HM, Shi ZH, Dumas J, Guertin MC. Should we patch corneal erosions?. Arch Ophthalmol. Mar 1997;115(3):313-7. [Medline].
[Best Evidence] Turner A, Rabiu M. Patching for corneal abrasion. Cochrane Database Syst Rev. 2006;(2):CD004764. [Medline].
Augeri PA. Corneal foreign body removal and treatment. Optom Clin. 1991;1(4):59-70. [Medline].
Aziz MA, Rahman MA. Corneal foreign body--an occupational hazard. Mymensingh Med J. Jul 2004;13(2):174-6. [Medline].
Howell RM. Corneal abrasion. eMedicine Journal [serial online]. 2007;Available at http://www.emedicine.com/emerg/topic828.htm.
Hulbert MF. Efficacy of eyepad in corneal healing after corneal foreign body removal. Lancet. Mar 16 1991;337(8742):643. [Medline].
Jayamanne DG, Bell RW. Non-penetrating corneal foreign body injuries: factors affecting delay in rehabilitation of patients. J Accid Emerg Med. Sep 1994;11(3):195-7. [Medline].
Kaiser PK. A comparison of pressure patching versus no patching for corneal abrasions due to trauma or foreign body removal. Corneal Abrasion Patching Study Group. Ophthalmology. Dec 1995;102(12):1936-42. [Medline].
Kay-Wilson LG. Localisation of corneal foreign bodies. Br J Ophthalmol. Dec 1992;76(12):741-2. [Medline].
Newell SW. Management of corneal foreign bodies. Am Fam Physician. Feb 1985;31(2):149-56. [Medline].
Yang X. Removal of corneal foreign bodies that project into the anterior chamber: use of a suture needle. Am J Ophthalmol. Jun 2000;129(6):801-2. [Medline].
Further Reading
Keywords
foreign material, cornea, foreign object, corneal abrasion, globe perforation, ocular trauma, ocular injury, rust ring
