Cloudy Cornea

The Problem

“My child’s eye looks cloudy.”

Common Causes

Infantile glaucoma

Corneal infection

Forceps injury

Peter’s anomaly

Other Causes

Sclerocornea

Congenital corneal dystrophy

Mucopolysaccharidosis

Trauma

KEY FINDINGS

History

Infantile glaucoma

Eye appears larger than normal Light sensitivity and excess tearing

Corneal infection

Most common in older children who wear contact lenses

Usually very uncomfortable Possible trauma, foreign body

Forceps injury

Difficult delivery requiring forceps

Peter’s anomaly

Cloudy central cornea at birth Other causes

May be associated with other systemic problems (e.g., mucopolysaccharidosis)

History of trauma

Examination

Infantile glaucoma Enlarged cornea Ground-glass appearance

Photophobia, excess tearing Corneal infection

Focal areas of increased corneal clouding Possible corneal foreign body

Eye appears bloodshot (conjunctival injection) Corneal dendrites (herpes simplex virus infection)

Corneal forceps injury

Cornea initially usually diffusely cloudy Later—oblique scars

Periocular and facial bruising and swelling from forceps

Peter’s anomaly

Central corneal clouding Peripheral cornea usually clear

WHAT SHOULD YOU DO?

Children with cloudy corneas should be referred promptly to a pediatric ophthalmologist.

What Shouldn’t Be Missed

Corneal infections require prompt treatment to minimize the risk of corneal ulcer and permanent visual damage. Infants with cloudy corneas are at high risk for amblyopia (similar to infants with cataracts), and early treatment may greatly improve the prognosis.

FIGURE 16–1 ■ Infantile glaucoma, right eye. Note right eye is larger than left, and central cornea is cloudy (arrow).

COMMON CAUSES

1.Infantile glaucoma. Glaucoma results from increased intraocular pressure. In infants and young children with glaucoma, the pressure may cause abnormal growth of the eye. The affected eye(s) appears larger than normal (Figure 16–1). The pressure interferes with the normal mechanisms that keep the cornea clear, and the cornea often has a ground-glass appearance. Haab striae (curvilinear scars in the corneal endothelium) may develop (Figure 16–2).

2.Corneal infections. Corneal infections are a potentially serious problem that may result in permanent visual loss. Bacterial infections are usually associated with a foreign body, either

FIGURE 16–2 ■ Curvilinear Haab striae (arrows) in a patient with infantile glaucoma.

FIGURE 16–3 ■ Central corneal ulcer with focal clouding. The lesion stains with fluorescein, indicating disruption of the corneal epithelium.

accidental or from contact lenses. (Figure 16–3). Herpes simplex virus may also affect the cornea (Figure 16–4).

3.Forceps injury. Forceps may be used by obstetricians during difficult deliveries. If the forceps produce direct pressure on the eye, children may develop traumatic opacification of the cornea. The opacification usually improves, but patients often have residual scarring and high astigmatism (Figure 16–5). They are at risk for deprivation amblyopia.

4.Peter’s anomaly. Peter’s anomaly is a congenital corneal abnormality that presents with opacification of the central cornea (Figure 16–6). The peripheral cornea is usually clear. Glaucoma and cataracts may also develop.

FIGURE 16–4 Peripheral herpes simplex viral corneal infection, stained with fluorescein. The lesion has a dendritic appearance.

FIGURE 16–5 ■ Corneal forceps injury. Note oblique linear Haab striae (arrows). The blood is on the corneal endothelium.

5.Other. Several other rare disorders may cause corneal clouding, including sclerocornea, congenital corneal dystrophies (Figure 16–7), and mucopolysaccharidosis (Figure 16–8). Cystinosis does not cause clouding per se, but patients usually have progressive crystalline deposits in their corneas, which cause light sensitivity (Figure 16–9). Trauma in older children may cause corneal foreign bodies, lacerations, and corneal edema (Figure 16–10).

FIGURE 16–7 ■ Diffuse corneal clouding secondary to congenital hereditary endothelial dystrophy.

FIGURE 16–8 ■ Diffuse corneal clouding due to Hurler syndrome (mucopolysaccharidosis type 1H).

FIGURE 16–10 ■ Diffuse corneal clouding following blunt injury. The linear opacities are caused by folds in the corneal endothelium.

APPROACH TO THE PATIENT

Opacification of the cornea is rare in infancy. It is most commonly secondary to glaucoma, but may also result from primary corneal disorders. In older children, cloudy corneas usually are caused by infection or trauma (Table 16–1).

History

In the absence of trauma (forceps injury), most infants who are born with cloudy corneas have glaucoma. Infantile glaucoma may be familial, and therefore a family history should be obtained. The primary corneal disorders that present in infancy with clouding are usually isolated to the eye, although Peter’s anomaly is sometimes associated with other abnormalities.

Cloudy corneas in older children usually result from extraneous causes, rather than primary corneal problems. The cornea has a rich supply of nerves, and

Table 16–1.

Causes of Corneal Clouding

■Infants

Glaucoma

Trauma (forceps)

Congenital corneal abnormality

–Peter’s anomaly

–Sclerocornea

Congenital infection (rare)

–Herpes simplex virus

■Older children

Systemic disease

–Mucopolysaccharidosis

–Cystinosis

Infection

–Contact lens

–Herpes simplex virus

Trauma

CHAPTER 16 Cloudy Cornea ■ 101

corneal disorders are usually very uncomfortable. Light sensitivity and excess tearing are frequent. Corneal foreign bodies may occur at any age, and the foreign body increases the risk of infection, which causes clouding. Foreign bodies usually present with a history of the abrupt onset of eye discomfort, and the cause of the foreign body is usually known. The history may be unclear in toddlers, particularly if the symptoms develop during unwitnessed activities. More severe traumatic corneal injuries usually have a clear history of the inciting incident. Contact lenses, particularly if they are not cared for properly, increase the risk of corneal infection.

A relatively small number of metabolic diseases, mucopolysaccharidosis being the most common, may have corneal clouding as one of their features (Figure 16–8). Affected children usually have several other systemic abnormalities that assist in the identification of these disorders.

Examination

The regular newborn examination should include a penlight evaluation of the cornea and red reflex. If the cornea is cloudy, details of the iris will be obscured and the red reflex will be abnormal. Many corneal disorders will also produce irritation, so the infants may be light sensitive and have increased tearing, which makes the examination more difficult. Congenital glaucoma and Peter’s anomaly may be bilateral or unilateral. The corneas are bilaterally affected in congenital corneal dystrophies and systemic diseases that cause corneal clouding.

Older children with corneal infections may be difficult to examine due to discomfort. The eye will usually appear bloodshot, and early infections usually have focal, rather than diffuse, areas of opacification (Figure 16–3). Foreign bodies, particularly wood or metal, may be visible with a penlight (Figure 16–11).

FIGURE 16–11 ■ Peripheral corneal foreign body (arrow).

102 ■ Section 2: Symptoms

Clear plastic or glass foreign bodies may be difficult to visualize without a slitlamp and anesthesia (topical or general). Examination of the red reflex may help identify foreign bodies. Herpes simplex virus corneal infections often have a distinctive dendritic appearance (Figure 16–4).

PLAN

If corneal clouding is noted during a routine newborn evaluation, prompt referral to a pediatric ophthalmologist is indicated (Figures 16–12). The prognosis for

vision depends on the type of abnormality. Infants with corneal opacities are at high risk for amblyopia.

Older children with corneal infections from any cause should be referred immediately to an ophthalmologist (Figures 16–13). If a child has a superficial corneal foreign body that is not infected, removal may be attempted with the use of topical anesthetic and a cotton-tipped applicator. If the foreign body cannot be removed, or if there are signs of infection, the child should be referred. Children with infected corneas are at risk for progressive opacification and vision loss. Early treatment decreases the risk of permanent problems.

WHAT SHOULDN’T BE MISSED

Similar to infantile cataracts, children with congenital corneal opacities have a very high risk of vision loss due to amblyopia. Early treatment is essential to maximize vision. Older children with corneal clouding also require prompt treatment, particularly for removal of foreign bodies and vigorous treatment of infection.

CHAPTER 16 Cloudy Cornea ■ 103

When to Refer

■Infants with cloudy corneas should be evaluated by an ophthalmologist promptly

■Older children with the acute onset of cloudy corneas should be evaluated promptly