Diagnosis
Traumatic corneal abrasion
Discussion
Differential Diagnosis:
The patient has a superficial, traumatic corneal abrasion based on clinical signs and symptoms. The differential diagnosis would include infectious keratitis (including herpetic keratitis), recurrent corneal erosion, neurotrophic epithelial defect or contact lens-associated keratopathy.
Definition:
A corneal abrasion is a disruption in the epithelium of the cornea. This is caused most commonly by trauma, contact lens use or foreign body. Typical sxs include intense irritation, foreign-body sensation, eye pain, excessive tearing, and/or an inability to open the eye due to pain and light sensitivity. Most abrasions result in significant discomfort to the patient due to the high level of corneal innervation.
Examination:
Obtaining a careful history, including the possibility of trauma or contact lens use, is important in evaluating patients with possible corneal abrasions. Some of the most common signs of a corneal abrasion include mild lid margin swelling and hyperemia, conjunctival hyperemia, increased tearing and lack of epithelium in the cornea (best visualized with fluorescein). Visual acuity might be decreased if the corneal abrasion is in the visual axis. Ensure to examine the fornix and evert the lids to rule out the presence of a foreign body. Fluorescein will stain the corneal epithelial basement membrane or the corneal stroma, which are exposed when the epithelial cells are removed with an abrasion. To apply fluorescein to the eye, use a drop that contains both fluorescein and an anesthetic agent or apply a drop of anesthetic to the tip of a fluorescein strip and gently placed the orange drop on the inferior conjunctiva by pulling the eyelid down. View the cornea under a cobalt blue light. A bright green stain highlights the areas of corneal abrasion. Fluorescein can also help demonstrate a full thickness corneal laceration with leakage of aqueous humor to the exterior of the eye, the Seidel sign. Use a drop of anesthetic early in the eye examination; this will make the patient feel more comfortable and able to open the eye. However, NEVER GIVE A PATIENT A BOTTLE OF ANESTHETIC DROPS TO TAKE HOME. A persistent epithelial defect and corneal melt can occur resulting in permanent vision loss.
Treatment:
A simple corneal abrasion can be treated with lubrication and antibiotic prophylaxis. Antibiotic drops or ointment formulation, and artificial tears or ointment can be used (ex. erythromycin ointment four times per day for five days or until the abrasion is healed). Symptoms should start to improve within 24-48 hours. Severe corneal abrasions can result in corneal scars, epithelial irregularity or recurrent erosion syndrome. Patients should NOT use their contact lenses until the epithelium is completely healed. The patient should be examined in one or two days by an eye care provider to ensure that the abrasion is resolving without pathology.
