Photophobia

A common symptom, photophobia is an abnormal sensitivity to light. In many patients, photophobia simply indicates increased eye sensitivity without an underlying disorder. For example, it can stem from wearing contact lenses excessively or using poorly fitted lenses. However, in others, this symptom can result from a systemic disorder, an ocular disorder or trauma, or the use of certain drugs.

History and physical examination

If the patient reports photophobia, find out when it began and how severe it is. Did it follow eye trauma, a chemical splash, or exposure to the rays of a sun lamp? If photophobia results from trauma, avoid manipulating the eyes. Ask the patient about eye pain and have him describe its location, duration, and intensity. Does he have a sensation of a foreign body in his eye? Does he have other signs and symptoms, such as increased tearing and vision changes? Does he have nuchal rigidity and severe headache?

Next, take the patient's vital signs and assess his neurologic status. Assess visual activity, unless the cause is a chemical burn. Follow this with a careful eye examination, inspecting the eyes'external structures for abnormalities. Examine the conjunctiva and sclera, noting their color. Characterize the amount and consistency of any discharge. Then check pupillary reaction to light. Evaluate extraocular muscle function by testing the six cardinal fields of gaze, and test visual acuity in both eyes.

During your assessment, keep in mind that although photophobia can accompany life-threatening meningitis, it isn't a cardinal sign of meningeal irritation.

Medical causes

Burns.With a chemical burn, photophobia and eye pain may be accompanied by erythema and blistering on the face and lids, miosis, diffuse conjunctival injection, and corneal changes. The patient experiences blurred vision and may be unable to keep his eyes open. With an ultraviolet radiation burn,photophobia occurs with moderate to severe eye pain. These symptoms develop about 12 hours after exposure to the rays of a welding arc or sun lamp.

Conjunctivitis.When conjunctivitis affects the cornea, it causes photophobia. Other common findings include conjunctival injection, increased tearing, a foreign-body sensation, a feeling of fullness around the eyes, and eye pain, burning, and itching. Allergic conjunctivitisis distinguished by a stringy eye discharge and milky red injection. Bacterial conjunctivitis tends to cause a copious, mucopurulent, flaky eye discharge that may make the eyelids stick together as well as brilliant red conjunctiva. Fungal conjunctivitis produces a thick, purulent discharge, extreme redness, and crusting, sticky eyelids. Viral conjunctivitis causes copious tearing with little discharge as well as enlargement of the preauricular lymph nodes.

Corneal abrasion.A common finding with corneal abrasion, photophobia is usually accompanied by excessive tearing, conjunctival injection, visible corneal damage, and a foreign-body sensation in the eye. Blurred vision and eye pain may also occur.

Corneal ulcer.A corneal ulcer causes severe photophobia and eye pain aggravated by blinking. Impaired visual acuity may accompany blurring, eye discharge, and sticky eyelids. Conjunctival injection may occur even though the cornea appears white and opaque. A bacterial ulcermay also cause an irregularly shaped corneal ulcer and unilateral pupillary constriction. A fungal ulcermay be surrounded by progressively clearer rings.

Iritis (acute).Severe photophobia may result from acute iritis, along with marked conjunctival injection, moderate to severe eye pain, and blurred vision. The pupil may be constricted and may respond poorly to light.

Keratitis (interstitial).Keratitis is a corneal inflammation that causes photophobia, eye pain, blurred vision, dramatic conjunctival injection, and grayish pink corneas.

Meningitis (acute bacterial).A common symptom of meningitis, photophobia may occur with other signs of meningeal irritation, such as nuchal rigidity, hyperreflexia, and opisthotonos. Brudzinski's and Kernig's signs can be elicited. Fever, an early finding, may be accompanied by chills. Related signs and symptoms may include headache, vomiting, ocular palsies, facial weakness, pupillary abnormalities, and hearing loss. With severe meningitis, seizures may occur along with stupor progressing to coma.

Migraine headache.Photophobia and noise sensitivity are prominent features of a common migraine. Typically severe, this aching or throbbing headache may also cause fatigue, blurred vision, nausea, and vomiting.

Uveitis.Anterior and posterior uveitis can cause photophobia. Typically, anterior uveitis also produces moderate to severe eye pain, severe conjunctival injection, and a small, nonreactive pupil. Posterior uveitis develops slowly, causing visual floaters, eye pain, pupil distortion, conjunctival injection, and blurred vision.

Other causes

Drugs.Mydriatics—such as phenylephrine, atropine, scopolamine, cyclopentolate, and tropicamide—can cause photophobia due to ocular dilation. Amphetamines, cocaine, and ophthalmic antifungals—such as trifluridine, vidarabine, and idoxuridine—can also cause photophobia.

Nursing considerations

▪ Promote the patient's comfort by darkening the room and telling him to close both eyes. Encourage use of sunglasses.

▪ Prepare the patient for diagnostic tests, such as corneal scraping and slit-lamp examination.

▪ Administer eyedrops and ointments, as ordered.

Patient teaching

▪ Teach the patient how to instill eyedrops or ointments.

▪ Discuss ways to reduce the discomfort of photophobia.

▪ Explain the disorder and treatment plan.

Copyright Details: Nursing: Interpreting Signs and Symptoms, Copyright © 2007 Lippincott Williams & Wilkins.

Other Book Chapters Related to Photophobia

Read excerpts from these other book chapters:

Copyright Details: Nursing: Interpreting Signs and Symptoms, Copyright © 2008 Williams & Wilkins.

More About Causes of Photophobia

• Back to symptom: Photophobia: Introduction (review 225 causes)
• Next Book Extract About Photophobia: Medications causing Photophobia
• All Book Extracts: All Online Book Extracts for Photophobia

More About This Book: Title: Nursing: Interpreting Signs and Symptoms Authors: Springhouse Publisher: Lippincott Williams & Wilkins Copyright: 2007 ISBN: 1-58255-668-7