health

Red Eye : DIAGNOSTIC REASONING: FOCUSED PHYSICAL EXAMINATION

Before conducting specific assessment procedures, perform an overall assessment of the patient to determine if there is visible injury, asymmetry of eyes and lids, or other abnormality, such as exophthalmia, to aid in timely assessment and referral.

Test Visual Acuity
In adults and children older than 3½ years, use a Snellen, Tumbling E, or Lippman chart. In children, the referral standard is 20/40 or worse in both eyes or a two-line difference between eyes. Retesting children before referral is suggested because they may perform better (within normal limits) on the second examination. For children younger than 3½ years, use an ophthalmoscope. Darken the room. Stay at arm’s length from the child and look at the eyes at a distance of 1 m or greater. When the child looks at the light, look at both red reflexes simultaneously and compare them. They should be red and equal in coloration. This indicates that the vision and binocular alignment are good and that no major pathologic condition of the cornea, lens, vitreous, or retina is present. If the reflexes are not equal, refer the child to an ophthalmologist.

Test Visual Fields
Testing of visual fields assesses the function of the peripheral vision and the central retina, optic pathways, and cortex. The visual fields confrontation test provides a gross assessment of peripheral vision. The peripheral field is damaged in glaucoma and by tumors or vascular lesions involving the visual fibers from the chiasm to the occipital cortex. Assess extraocular movements by testing the six
cardinal positions of gaze, assessing the corneal light reflex, and performing the cover-uncover test.

Inspect the Lids, Lid Margins, Periorbital Tissues, and Orbital Tissues
Note redness or swelling of the lids. Look for lid lesions. Inspect the lid margins. Evert the lids and note appearance. Unilateral inflammation of the lids and periorbital
tissues without proptosis or limitation of eye movement characterizes periorbital cellulitis. If proptosis and/or limitation of eye movement are present, orbital cellulitis is a likely cause. Erythematous swelling without systemic signs may
be caused by contact dermatitis. All exposed skin should have the same coloring. A lid that is injected, swollen, and irritated may be so because of an underlying disease process in the conjunctiva, cornea, sclera, or intraocular area.
361 Examine for the presence of focal or diffuse inflammation. Blockage of the glands along the lash line may produce localized or diffuse redness or flaking of the skin as a result of staphylococcal or seborrheic causes. With viral conjunctivitis, lids appear to have follicular changes (small aggregates of lymphocytes) in the palpebral conjunctiva. Lids that have large, flattened, cobblestone-like papillary lesions of the palpebral conjunctivae are characteristic of vernal conjunctivitis. Inflammation of the lid margins in all four lids with associated loss of eyelashes is common in children; this condition is known as blepharitis. The lash line is waxy, scaling, red, and irritated, and the eyes have slightly swollen lid margins. Eye pain with no external inflammation suggests referred causes, such as sinusitis, carotid artery aneurysm, temporal arteritis, migraine or cluster headache, or trigeminal neuralgia. Optic neuritis can also cause eye pain without inflammation.

Observe for Entropion and Ectropion
The lacrimal puncta are turned backward slightly to catch the pool of tears in the inner canthus and to prevent tears spilling over the cheeks. Anatomical changes of the lid margins can develop into entropion, when the eyelid margin turns inward. The eyelashes contact the corneal and conjunctival surfaces, and the patient reports discomfort. Scarring can occur. Ectropion occurs when the eyelid margin turns outward. A pool of stagnant tears results and does not allow proper mechanical protection of the cornea and conjunctiva. The exposed tarsal conjunctiva is also susceptible to repeated trauma.

Evert the Eyelid
If there is a history of trauma, eversion of the eyelid is necessary to detect a possible foreign body. This is done by first having the patient look down. Hold the upper eyelashes straightforward. Push down on the upper tarsal border with a cotton-tipped applicator. The lid everts. Hold the eyelid in this position by moving fingers to the brow. To undo, hold the lashes and pull gently forward while asking the patient to look up.

Inspect the Conjunctiva
Note bilateral or unilateral redness and the location of redness on the conjunctiva. Distinguish between peripheral or circumcorneal injection (ciliary flush). Ciliary flush is the deep conjunctival or episcleral blood vessel injection around the limbus (junction between the cornea and conjunctiva), dilating in response to corneal disease or injury. It is frequently associated with keratopathy, uveitis, and episcleritis/scleritis. Abrasions and ulcers of the cornea cause increased redness of the globe around the corneal limbus, appearing as a reddish ring surrounding the cornea. Note any discharge. Look for visible lesions or foreign bodies on the conjunctiva. Conjunctival inflammation as a result of infection causes a red eye with peripheral injection that is maximal toward the fornix (the fold between globe and lid). Peripheral injection involves the bulbar conjunctiva without edema or exudate, and the cornea is spared. Look for swelling of the conjunctiva (chemosis).
Fluid can accumulate beneath the loosely attached bulbar conjunctiva, causing it to balloon away from the globe. Chemosis occurs most frequently and dramatically with hyperacute bacterial conjunctivitis. Subconjunctival hemorrhage causes a bright red splash of blood that is visible on the conjunctiva and sclera. Without a history of trauma or bleeding diathesis and no presence of retinal hemorrhage, the cause may be intravascular pressure from coughing, sneezing, or straining. Systemic autoimmune processes, such as juvenile rheumatoid arthritis, serum sickness, and StevensJohnson syndrome, may cause conjunctivitis. Conjunctivitis around the limbus of the eye is seen in juvenile rheumatoid arthritis. A localized degenerative process of the substantia
propria of the conjunctiva, known as pinguecula, may invade the superficial cornea. These are yellow, elevated nodules of fibropathic material that are usually adjacent to the cornea on the nasal side. Look at the palpebral conjunctiva and the fornices for foreign bodies and pterygia, which are neovascularized structures that can encroach on the cornea and form a pannus, an abnormal layer of fibrous tissue or granulation tissue, which interferes with vision.

Inspect the Sclera
Note the color. The sclera gives the eye its white appearance. Inflammation (scleritis) causes a dusky red color.

Examine the Cornea
Test the corneal light (red) reflex. Note if the cornea is hazy or has opacities. Look for visible foreign bodies. The normal cornea is transparent, with blood vessels only at the limbus (the junction between cornea and conjunctiva). Illumination of the cornea tangentially may show abnormalities, such as abrasions or foreign bodies. These imperfections of the corneal surface will produce an abnormal light reflex or a break in the image as the light reflects off the cornea. The blood vessels around the limbus dilate in response to corneal disease or injury. When topical application of fluorescein to the cornea reveals dendrite ulcers, you should suspect herpes simplex virus.

Examine the Iris, Pupil, and Lens
Note pupil size and equality. Note transparency of lens. Test pupillary reaction (direct and consensual). Note any photophobia. The anterior chamber should contain only clear aqueous humor. Trauma may cause blood to accumulate in the chamber; this is known as a hyphema. The shock wave produced by the sudden compression and decompression of the cornea is transmitted through the eye and may result in a tear in the ciliary body. Disruption of the anterior arterial circle of this structure produces bleeding that accumulates. The hyphema appears as a bright red or dark red fluid level between the cornea and iris or as a diffuse murkiness of the aqueous humor. Pus may also accumulate in this space in association with corneal infection. This is known as hypopyon. All hyphemas are abnormal and must be referred to an ophthalmologist. The pupil is the central aperture of the iris. It floats in the aqueous humor and divides the anterior segment into anterior and posterior chambers, which communicate throughout the pupillary aperture. It slides freely on the anterior surface of the lens when dilating and contracting. Conditions that affect this anatomy cause pupil abnormalities. Inflammation of the iris (iritis) causes reduction in the reactive capacity of the iris and inequality of pupils. Acute increased intraocular pressure causes the space in the anterior chamber to become very shallow, resulting in a dilated, fixed, oval pupil. The lens is normally transparent and not visible
on inspection; however any visible clouding of the lens seen through the pupil is indicative of cataract formation.

Perform Ophthalmoscopy
When looking for the red reflex, note any corneal opacity as well as the depth of the opacity. Corneal opacities move in the opposite direction of the ophthalmoscope, lens opacities stay still, and vitreous opacities move in the same direction as the ophthalmoscope. Corneal clouding (edema) is seen with glaucoma.
Look for a large and deepened cup if you suspect glaucoma. Early in the course of the disease, the ophthalmoscopic examination may be normal. Do not use mydriatic agents if you suspect glaucoma.

Test Extraocular Movements
Test eye movement in all six fields of gaze. Note pain or restriction. Inflammation or underlying periostitis and impaired venous drainage as a result of reactive inflammation cause restrictive eye movement and proptosis (exophthalmia). Decreased range of motion can also occur with orbital cellulitis.

Palpate the Lid/Lacrimal Puncta
Note if gentle palpation of each lacrimal sac produces any material that regurgitates into the eye. Unilateral swelling over the lacrimal sac on the lid margin at the side of the nose because of infection or obstruction of the lacrimal drainage system is common. Infection of the meibomian glands of the eyelids (hordeolum or internal stye) and the glands of Zeis or Moll (hordeolum or external stye) produces pain on palpation. Internal styes are generally large and very tender and may point to the conjunctiva or epidermis portion of the lid. External styes are small and superficial and point only to the epidermis side. Granulomatous inflammation of a meibomian gland
nodule that is firm and not tender and has no inflammatory signs is a chalazion.

Examine the Tympanic Membranes
Examination of the tympanic membrane is necessary because of the frequent association with atypical H. influenzae acute otitis media (otitis-conjunctivitis syndrome).

Palpate Preauricular Nodes
The preauricular nodes are usually palpable with a viral infection of the eyes. Palpable adenopathy is uncommon in acute bacterial conjunctivitis but may occur in hyperacute infection caused by N. gonorrhoeae or Neisseria meningitidis.