BRS – Pediatrics: Ophthalmology

BRS – Pediatrics: Ophthalmology

Source: BRS Pediatrics, 2019

I. Ocular Examination and Vision Screening

A. The purpose of ocular examination and vision screening is early detection and treatment of pediatric ocular disease. Delay in diagnosis may result in irreversible vision loss and even death.
B. Vision screening principles can be remembered using the acronym I-ARM PLUS (Inspection,
Acuity assessment, Red reflex testing, Motility assessment).

1. Inspection includes evaluation for pupil and eyelid symmetry, head turn or head tilt (i.e., torticollis), and conjunctival injection.
2. Acuity assessment

a. Neonates and infants: evaluation of eye fixation, tracking of light or objects, and pupillary responses
b. Children: use of eye charts or cards

3. Red reflex assessment, in which a direct ophthalmoscope is directed at the patient’s eyes from a distance of 2–3 feet (Bruckner test), is the single best screening examination for infants and children. Table 18-1 presents information about the differential diagnosis of an abnormal red reflex.
4. Motility assessment and eye alignment. Motility assessment of each eye involves having the child follow a target in all directions. At the same time, alignment is assessed by evaluating for the symmetry of light reflecting off both corneas (Hirschberg test).
5. Plus. Instrument-based objective vision screening with devices that measure the focusing and alignment of eyes in preverbal children

Table 18-1. Differential Diagnosis of an Abnormal Red Reflex

Disorder Red Reflex Finding
Cataract Dark, dull, or white reflex
Vitreous hemorrhage Dark or dull reflex
Retinoblastoma Yellow or white reflex
Anisometropia Unequal red reflex
Strabismus Brighter red reflex in deviated eye
Corneal light reflex will be uncentered
Glaucoma Dull reflex

II. Normal Visual Development and Amblyopia

A. Visual development
1. Visual acuity is poor at birth, in the range of 20/200, as a result of physiologic immaturity of the visual cortex responsible for visual processing.
2. Visual acuity rapidly improves during the first 3–4 months of life, as a clear in-focus retinal image stimulates functional and structural development of the visual centers of the brain.
3. Normal visual development is dependent on both of the following:
a. Proper eye alignment
b. Equal visual stimulation of each retina with clearly focused images
4. Abnormal visual development results from the following:
a. Improper eye alignment, such as uncorrected strabismus [see section IX] b. Any pathologic condition that blocks retinal stimulation, such as a congenital cataract [see section VIII.A] 5. Visual development is most critical during the first 3–4 months of life. Any pathologic condition that disrupts alignment or retinal stimulation during this period may result in poor vision as a result of amblyopia [see section II.B].
6. Binocular vision requires the integration of sufficiently clear and equal monocular retinal images from both eyes into a single, three-dimensional perception (binocular, sensory fusion). Binocular cortical connections are present at birth. However, appropriate visual input from each eye is necessary to refine and maintain these binocular neural connections.
7. Normal depth perception (stereopsis), similar to normal visual development, may be impaired because of the following:
a. Improper eye alignment
b. Any pathologic condition that unilaterally blurs the retinal image, such as a congenital cataract
B. Amblyopia
1. Definition. Amblyopia is subnormal visual acuity caused by abnormal visual development early in life.
2. Epidemiology. Amblyopia is the most common cause of decreased vision during childhood and occurs in approximately 2–4% of the general population.
3. Etiology. Any pathologic condition that causes abnormal retinal stimulation can cause amblyopia.
a. Eye misalignment (strabismus: see section IX). If a child has a strong preference for one eye and constant suppression of the nonpreferred eye, amblyopia will develop in the nonpreferred eye.
b. Any pathologic condition that causes a blurred visual image. Opacification of the lens (cataract), severe uncorrected refractive error, significant differences in refractive errors between the eyes (anisometropia), and vitreous opacities (hemorrhage) all lead to poor visual stimulation, and therefore abnormal visual development.
4. Clinical features. Severity of amblyopia depends on when the abnormal stimulus began, the length of exposure to the abnormal stimulus, and the severity of the blurred image.
a. The earlier the onset, the longer the duration of the abnormal stimulus, and the more blurry the image, the more severe the vision loss.
b. Children are most susceptible to amblyopia during the first 3–4 months of life, the

period of critical visual development.
5. Diagnosis
a. In infants and preverbal children, the bilateral red reflex test [see section I.B.3] is the best screening test.
b. In older children, formal acuity testing is the best screening test.
6. Management. Early detection and early intervention are critical to the treatment of amblyopia.
a. A clear retinal image should be ensured by correcting any refractive errors with eyeglasses or by surgically removing any visually significant lens opacities.
b. Either depriving the normal eye of clear vision through occlusion or causing blurriness by an eye drop forces the use of the amblyopic eye.
c. The earlier the intervention, the better the prognosis.

III. Conjunctivitis and Red Eye
Conjunctivitis is a nonspecific finding that refers to conjunctival inflammation. It may be the result of infectious or noninfectious causes. The causes of conjunctivitis vary with the age of the patient.

A. Neonatal conjunctivitis (ophthalmia neonatorum)
1. Definition. Conjunctivitis occurring during the first month of life
2. Etiology. Causes of neonatal conjunctivitis may include infections or chemical irritation.
a. Infection is acquired from the vaginal canal during birth or from hand-to-eye contamination from infected individuals. Infectious agents include Neisseria gonorrhoeae, Chlamydia trachomatis, and herpes simplex virus.
b. Chemical conjunctivitis. Chemical irritation (chemical conjunctivitis) results from drops or ointment that are topically instilled into a newborn’s eyes as prophylaxis against N. gonorrhoeae. Chemical conjunctivitis is most often secondary to 1% silver nitrate. Other medications used to prevent N. gonorrhoeae, such as 1% tetracycline and 0.5% erythromycin, tend to be less irritating to the conjunctiva.
1. Chemical conjunctivitis is the most common cause of red, watery eyes in the
first 24 hours of life.
2. This self-limited condition lasts for less than 24 hours.
3. Clinical features, diagnosis, and management are found in Table 18-2.
4. Differential diagnosis of a red, teary eye in newborns also includes the following:
a. Congenital glaucoma [see section VI], which is characterized by tearing, an enlarged globe, and corneal edema
b. Dacryocystitis (infection of the nasolacrimal sac)
c. Endophthalmitis (infection within the vitreous and aqueous fluid), a rare but devastating infection that often results in blindness
B. Red eye in older infants and children
1. Etiology. The differential diagnosis of red eye in infants and children is extensive (Figure 18-1). The most common causes include viral, bacterial, and allergic conjunctivitis, as well as blepharitis (eyelid inflammation).
2. Evaluation
a. History, which often establishes the cause
1. Infectious causes are suggested by history of contact with others who have conjunctivitis.
2. Allergic conjunctivitis is suggested by severe itchiness and is usually seasonal.
3. Conjunctivitis associated with contact lens use may be secondary to allergy to the contact lens solution, to a corneal abrasion, or to a vision-threatening bacterial corneal ulcer.
4. Unilateral conjunctivitis may be associated with a foreign body, corneal ulcer, or herpes simplex keratitis.
b. Ocular examination (I-ARM acronym; see section I.B)
c. Fluorescein staining of the corneal epithelium is performed to evaluate for an abrasion of the corneal tissue. Positive staining is most commonly associated with trauma, but may also be associated with a bacterial corneal ulcer or with herpes simplex keratitis.
3. Specific causes of conjunctivitis. The distinguishing clinical features of the common causes of pediatric red eye are presented in Table 18-3.
a. Bacterial conjunctivitis
1. Etiology. Causes most commonly include nontypeable Haemophilus

influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, and
Staphylococcus aureus.
2. Clinical features. Purulent discharge, conjunctival erythema, and lid swelling are usually present. Bilateral involvement is common. Some patients have associated otitis media.
3. Diagnosis. History and clinical presentation are the basis of diagnosis.
a. Conjunctival cultures and Gram stain are not performed routinely for mild to moderate infections, and patients are usually treated empirically.
b. However, conjunctival cultures and Gram stain should be obtained in
severe cases.
4. Management
a. Topical antibiotics are effective and include bacitracin, sulfacetamide, polymyxin B and trimethoprim sulfate, gentamicin, tobramycin, ofloxacin, and erythromycin.
b. Indications for referral to an ophthalmologist include severe eye involvement, conjunctivitis associated with contact lens use, suspected corneal ulcer, or lack of improvement with topical antibiotics.
b. Viral conjunctivitis
1. Pharyngoconjunctival fever is characterized by an upper respiratory infection that includes pharyngitis, fever, and bilateral conjunctivitis.
a. Etiology. The cause is adenovirus, types 3 and 7.
b. Clinical features
1. Symptoms and signs: severe watery conjunctival discharge, hyperemic conjunctiva, chemosis (conjunctival edema), preauricular lymphadenopathy, and typically a foreign body sensation caused by corneal involvement
2. Highly contagious and lasts for 2–3 weeks
c. Management. Treatment is supportive and includes cool compresses and topical nonsteroidal anti-inflammatory drug (NSAID) drops. Antibiotics may be necessary if bacterial superinfection occurs.
2. Epidemic keratoconjunctivitis is clinically similar to pharyngoconjunctival fever, but symptoms are confined to the eyes.
a. Etiology. The cause is adenovirus, types 8, 19, and 37.
b. Clinical features
1. Symptoms and signs: petechial conjunctival hemorrhage, preauricular lymphadenopathy, and a pseudomembrane along the conjunctiva
2. Photophobia from corneal inflammation (keratitis) caused by a hypersensitivity reaction to the virus (occurs in one-third of patients)
3. Lack of fever or pharyngitis
4. Highly contagious
c. Management. Treatment is supportive, including cool compresses and topical NSAID drops. Children with corneal involvement should be referred to an ophthalmologist.
3. Primary ocular herpes simplex virus
a. Etiology. The cause is herpes simplex virus type 1 (HSV-1) and typically represents the initial exposure to HSV-1 virus.
b. Clinical features
1. Skin eruption with multiple vesicular lesions

2. Corneal ulcer (rare)
c. Diagnosis. History, clinical presentation, and positive viral culture or direct fluorescent antibody staining of vesicular fluid are the basis of diagnosis.
d. Management
1. Systemic or topical acyclovir may speed recovery if administered within 1–2 days of onset.
2. Topical antibiotics applied to the skin may prevent secondary bacterial infection.
c. Allergic conjunctivitis
1. Epidemiology. Allergic conjunctivitis is most typically seasonal, often accompanying seasonal allergic rhinitis. It affects 10% of the population.
2. Etiology. The cause is a type 1 hypersensitivity reaction.
3. Clinical features. Marked itching and watery discharge are present.
4. Diagnosis. History and clinical presentation are the basis of diagnosis.
5. Management
a. Removal of environmental allergens
b. Topical mast cell–stabilizing drops, such as cromolyn
c. Topical antihistamines
d. Hemorrhagic conjunctivitis is a dramatic presentation of pediatric red eye in which the child presents with both conjunctivitis and subconjunctival hemorrhage. Causes include infection with H. influenzae, adenovirus, and picornavirus.
e. Blepharitis
1. Definition. Blepharitis is eyelid inflammation.
2. Epidemiology. Blepharitis is one of the most common causes of red eye.
3. Etiology. The usual cause is S. aureus infection.
4. Clinical features. Burning, crusting, and scales at the eyelash base; thickened and hyperemic eyelid margins; broken or absent eyelashes; and a history of awakening in the morning with eyelashes stuck together are characteristic.
5. Diagnosis. History and clinical presentation are the basis of diagnosis.
6. Management. Treatment includes eyelid hygiene, in which eyelids are scrubbed twice daily with baby shampoo. Topical erythromycin ointment may also be applied.

Table 18-2
Etiology, Clinical Features, Diagnosis, and Management of Neonatal Conjunctivitis

Etiology Onset and Clinical Features Conjunctival Studies Management
Chemical Within first 24 hours Negative Gram stain No treatment necessary
Watery discharge Few PMNs
Neisseria
gonorrhoeae 2–4 days of life Gram-negative intracellular
diplococci Intravenous cefotaxime and
topical erythromycin
Purulent
discharge
Eyelid swelling Positive gonococcal culture Treat parents
Can lead to
corneal ulcer
Chlamydia
trachomatis 4–10 days of life Cytoplasmic inclusion
bodiesPositive DFA or culture Oral erythromycin
Serous or purulent
discharge Treat parents
Variable lid
swelling

PMNs = polymorphonuclear neutrophils; DFA = direct fluorescent antibody assay; HSV = herpes simplex virus.

FIGURE 18.1 Differential diagnosis of red eye in older infants and children.

Table 18-3
Distinguishing Clinical Features of Conjunctivitis

Clinical Feature Bacterial Viral Allergic Blepharitis
Discharge Purulent Watery Watery or mucoid Minimal
Itching Minimal Minimal Severe Minimal (irritation rather
than itching)
Preauricular
lymphadenopathy Absent Common Absent Absent
Laboratory findings Bacteria and PMNs on
Gram stain No bacteria on
Gram stain Eosinophils on
conjunctival scraping Positive culture for
Staphylococcus aureus
PMNs = polymorphonuclear neutrophils.

IV. Abnormal Tearing
A. Nasolacrimal duct (NLD) obstruction
1. Definition. NLD obstruction is failure of complete canalization of the lacrimal system that results in obstruction to tear outflow. Obstruction typically occurs distally at Hasner valve.
2. Epidemiology. NLD occurs in 1–5% of children.
3. Etiology. The cause of incomplete canalization is unknown.
4. Clinical features
a. Watery eye with increased tear lake (meniscus of tears upon the lower eyelid margin that spill over onto the cheek and eyelid)
b. Matted eyelashes
c. Mucus in the medial canthal area
d. Bilateral involvement in one-third of patients
5. Management
a. Observation only is needed for most children.
1. Over 80% of cases resolve spontaneously within 9–12 months.
2. Nasolacrimal massage may help open the distal obstruction.
3. Topical antibiotics are administered if infection is present.
b. NLD probing, in which a small steel wire is passed through the nasolacrimal system through Hasner valve into the nose, will cure NLD obstruction in most cases. It is typically performed between 6 and 12 months of age.
B. Amniotocele (dacryocele)
1. Definition. Amniotocele is swelling of the nasolacrimal sac.
2. Etiology. The cause is accumulation of fluid as a result of NLD obstruction.
3. Clinical features
a. Bluish swelling in the medial canthal area may be apparent and represents fluid sequestered within the distended nasolacrimal sac.
b. Infection may occur, manifesting as warmth, erythema, tenderness, and increased induration.
4. Management
a. Local massage, if there is no evidence of infection
b. Intravenous antibiotics and urgent NLD probing if infection is present

V. Ocular Trauma
A. Retinal hemorrhages
1. Etiology
a. Retinal hemorrhages are highly suggestive of child abuse. (Physical characteristics of child abuse are described further in Chapter 20, section VI.)
b. Nonabuse causes of retinal hemorrhages include birth trauma, leukemia, increased intracranial pressure, malignant hypertension, bacterial endocarditis, immune thrombocytopenic purpura, and rarely, cardiopulmonary resuscitation.
2. Clinical features. Retinal hemorrhages appear as hemorrhagic dots and blots, or hemorrhage within the preretinal vitreous on a dilated funduscopic examination.
B. Corneal abrasion
1. Definition. Corneal abrasion is damage to, and loss of, corneal epithelium.
2. Etiology. The cause is trauma, including injury from contact lens use.
3. Clinical features
a. Severe pain, tearing, and photophobia
b. Foreign body sensation
4. Diagnosis. Identification of the abrasion on fluorescein staining of the cornea is the basis of diagnosis.
5. Management. Complete healing usually occurs within 24–48 hours.
a. Placement of a protective shield or patch for 24–48 hours may be recommended in severe cases.
b. Instillation of a topical antibiotic prevents bacterial superinfection.
c. Ophthalmologic consultation to evaluate for a bacterial corneal ulcer is necessary if the abrasion is associated with contact lens use.
C. Hyphema
1. Definition. Hyphema is blood within the anterior chamber.
2. Etiology
a. Blunt trauma is the most frequent cause. Blunt trauma compresses the globe, and when the globe subsequently re-expands, the iris vasculature tears, resulting in bleeding.
b. Nontraumatic causes include iris neovascularization (associated with diabetes mellitus, intraocular tumors, and retinal vascular diseases), clotting disorders, and iris tumors (e.g., melanoma, juvenile xanthogranuloma).
3. Clinical features
a. Impaired vision. As blood settles, a blood-aqueous fluid level may be seen. A large hyphema may obscure the pupil and iris, thereby impairing vision.
b. Complications
1. Rebleeding 3–5 days after initial injury can occur due to repeat trauma or an underlying bleeding diathesis, or as the clot retracts.
2. Glaucoma
3. Staining of the cornea with blood
4. Optic nerve damage in children with sickle cell disease
4. Management. Treatment includes ophthalmologic consultation, pain control, prevention of vomiting (which may cause a sudden increase in intraocular pressure) and bed rest for at least 5 days.
D. Orbital floor fracture (“blow-out” fracture)
1. Etiology. Blunt trauma to the eye or orbital rim fractures the orbital floor, which is normally thin and easy to fracture.

2. Clinical features
a. Orbital fat and the inferior rectus muscle can become entrapped within the fracture, leading to diplopia as a result of restricted vertical eye movement, to strabismus, and to enophthalmos (backward displacement of the globe into the orbit).
b. Numbness of the cheek and upper teeth below the orbital fracture may occur as a result of infraorbital nerve injury.
3. Management
a. Empiric oral antibiotics are administered to prevent infectious contamination of the orbit from organisms from the maxillary sinus.
b. Surgical repair is indicated if diplopia persists 2–4 weeks after injury or if enophthalmos is significant.

VI. Congenital Glaucoma
A. Definition. Congenital glaucoma is increased intraocular pressure occurring at or soon after birth.
1. Normal intraocular pressure in infants is 10–15 mm Hg. Infants with congenital glaucoma have intraocular pressures exceeding 30 mm Hg.
2. Congenital glaucoma is very different from adult glaucoma.
a. Adult glaucoma is characterized by increased intraocular pressure that damages the optic nerve but does not change the size of the eye.
b. Congenital glaucoma not only results in optic nerve injury but also expands the size of the eye, because the eye wall is much more elastic during infancy. Congenital glaucoma results in corneal edema, corneal clouding, and amblyopia.
B. Etiology
1. Outflow of aqueous humor is reduced because of maldevelopment of the trabecular meshwork.
2. Most cases are inherited in an autosomal dominant fashion.
3. Other causes include infection (e.g., congenital rubella syndrome), ocular abnormalities (e.g., aniridia [absence of the iris]), or genetic syndromes, (e.g., Sturge–Weber syndrome, neurofibromatosis, Marfan syndrome).
C. Clinical features
1. Ocular enlargement, tearing, photophobia, enlarged cornea, corneal clouding, and a
dull red reflex are common.
2. Bilateral involvement is present in 70% of patients.
3. Glaucoma may be initially misdiagnosed as NLD obstruction because of the presence of tearing, but is distinguished by the presence of a normal red reflex in patients with NLD obstruction.
D. Management
1. Surgery to open outflow channels is almost always required.
2. Topical or systemic medications, such as β-adrenergic and carbonic anhydrase inhibitors, may help to lower intraocular pressure.
E. Prognosis. Congenital glaucoma, if not detected and treated surgically early, leads to blindness.

VII. Retinopathy of Prematurity (ROP)
A. Definition. ROP is the proliferation of vessels in the immature retina, seen in premature infants exposed to oxygen.
B. Etiology
1. The precise cause of ROP is unknown; however, vascular endothelial growth factors are posited to be involved. High concentrations of oxygen play a major role in the development of ROP.
2. Other risk factors include low birth weight (<1500 g), young gestational age, blood transfusions, respiratory distress syndrome (surfactant deficiency syndrome), and intracranial hemorrhage.
C. Late complications. Myopia, astigmatism, amblyopia, strabismus, and blindness may develop.
D. Management
1. Ophthalmologic examinations are performed every 1–2 weeks in patients with ROP to monitor for normal maturation of retinal vessels.
2. If disease is severe, retinal cryotherapy and laser therapy may be effective to prevent blindness.
E. Screening and prevention
1. Early detection is essential.
2. Minimizing the amount of oxygen delivered and effective treatment of respiratory distress syndrome (see Chapter 4, section VI) are the two most important factors for prevention of ROP.
3. Infants born at a gestational age of 28 weeks or less or with a birth weight of less than 1500 g should have a dilated ophthalmoscopic examination at 4–6 weeks of age.

VIII. Leukocoria
Leukocoria is a white pupil and refers to an opacity at or behind the pupil. It may be caused by a cataract, by an opacity within the vitreous, or by retinal disease, such as retinoblastoma.

A. Congenital cataract
1. Definition. Congenital cataract is a crystalline opacity of the lens present at birth.
2. Etiology. The majority of cataracts are idiopathic. Other causes include the following:
a. Genetic syndromes, such as Down, Noonan, Marfan, Alport, and Smith–Lemli–
Opitz syndromes
b. Nonsyndromic genetic inheritance
c. Metabolic derangements, such as hypoglycemia, galactosemia, and diabetes mellitus
d. Intrauterine infections, such as cytomegalovirus and rubella
e. Trauma
3. Management. Treatment includes evaluation for underlying disease and early surgery to prevent amblyopia.
4. Prognosis. Congenital cataracts treated within the first weeks of life have a good prognosis, whereas surgery performed after 2–3 months of age is associated with poor visual outcome.
B. Retinoblastoma
1. Definition. Retinoblastoma is a malignant tumor of the retina.
2. Epidemiology
a. Retinoblastoma is the most common ocular malignancy in childhood.
b. The average age at presentation is 13–18 months. More than 90% of cases are diagnosed before 5 years of age, which makes retinoblastoma a tumor of toddlers and preschool children.
3. Etiology
a. Mutation or deletion of a growth suppressor gene on both alleles on the long arm of chromosome 13. Because the development of retinoblastoma requires two deletions or mutations (one on each allele), the cause has been termed the “two-hit” model.
b. Mutations may be sporadic or inherited in an autosomal recessive fashion.
4. Clinical features
a. Leukocoria and strabismus are the two most common presenting signs. Often a careful history will elicit that an observing parent has noticed the leukocoria.
b. Glaucoma, vitreous hemorrhage, retinal detachment, and hyphema are less common presenting signs.
c. Calcification within the tumor, identified on imaging studies of the eye, is a
hallmark of retinoblastoma.
5. Diagnosis. Visual inspection with an ophthalmoscope is the basis of diagnosis. Ocular ultrasound or computed tomographic scan of the orbit can further evaluate the tumor and assess for tumor extension.
6. Management
a. Early diagnosis is critical. Retinoblastoma should be suspected in any child with leukocoria.
b. Large tumors involving the macula have a poor prognosis and are generally treated by removal of the entire eye (i.e., enucleation).
c. Smaller tumors may be treated with external beam radiation; however, radiation may induce formation of secondary tumors.

d. Very small peripheral tumors may be treated with cryotherapy or laser photocoagulation.
e. Systemic and local intraretinal arterial chemotherapy are additional treatments.
7. Prognosis. Outcome is excellent if retinoblastoma is identified early. The cure rate is 90% if the tumor does not extend beyond the sclera or into the orbit. Retinoblastoma is uniformly lethal if untreated.

IX. Strabismus
A. Definition. Strabismus is misalignment of the eyes.
1. Esotropia refers to the eye turned nasally.
2. Exotropia refers to the eye turned laterally.
3. Vertical strabismus refers to the eye turned up or down.
4. Pseudostrabismus is a prominence of the epicanthal folds that results in the false appearance of strabismus, even though the eyes are actually appropriately aligned.
B. Etiology. The cause of most childhood strabismus is usually unknown. However, brain tumors, farsightedness (hypermetropia), or neurologic processes causing paresis of cranial nerves III, IV, or VI may also cause strabismus.
C. Clinical features
1. If strabismus occurs before 5–7 years of age, the child suppresses the image in the deviated eye. If this suppression is prolonged, amblyopia may result.
2. If strabismus occurs later than 5–7 years of age (i.e., acquired strabismus), the mature visual system is unable to suppress the image in the deviated eye, and diplopia results.
3. Acquired strabismus, decreased eye movement, ptosis, decreased vision, and abnormal red reflex are all red flags that suggest a dangerous underlying cause, such as a tumor or neurologic process.
D. Management. Treatment depends on the underlying cause.
1. Ocular patching or use of eye drops to cause blurring to the normal eye to prevent amblyopia is important.
2. Strabismus associated with farsightedness is initially treated with corrective lenses.
3. Surgery is often required to correct any misalignment that does not respond to patching or glasses.

Review Test
1. A 1-month-old male infant is brought to the office for a routine health maintenance visit. The infant has been feeding well, and the parents have no concerns. Physical examination is unremarkable except for a lens opacity in the right eye. Which of the following statements regarding this finding is most correct?
A. Because of this infant’s age, he is not susceptible to amblyopia.
B. Immediate referral for cataract surgery is indicated.
C. The opacity was probably not present at birth but has developed after birth.
D. Surgery can be safely delayed until 6 months of age.
E. Red reflex testing is normal and does not identify this finding.
2. A 3-year-old girl with a normal past medical history presents with a 5-day history of bilateral mucoid conjunctival discharge and conjunctival hyperemia. The girl is rubbing her eyes, and her mother believes that her daughter’s eyes are very itchy. Which of the following statements regarding the most likely diagnosis is correct?
A. The girl’s symptoms are secondary to a type 2 hypersensitivity reaction.
B. Topical antihistamines would be effective.
C. Staphylococcus aureus is the likely pathogen.
D. Coexisting rhinitis would be unusual.
E. Topical polymyxin B and trimethoprim sulfate is an effective treatment.
3. A 14-year-old boy who wears contact lenses presents with conjunctival hyperemia and severe photophobia of the right eye. Which of the following statements regarding his diagnosis and management is most correct?
A. Immediate ophthalmologic evaluation is necessary.
B. Viral conjunctivitis is likely and supportive care should be provided.
C. Eosinophils are seen on conjunctival scraping.
D. Fluorescein staining is normal.
E. Topical erythromycin should be prescribed and the patient should follow up if no improvement is seen in 1 week.
4. A 5-year-old boy presents with a history of fever, bilateral watery conjunctival discharge, sore throat, and a foreign body sensation in his eyes. Physical examination is notable for bilateral conjunctival hyperemia with watery discharge and bilateral preauricular lymphadenopathy. Which of the following statements regarding the most likely diagnosis is correct?
A. Topical nonsteroidal anti-inflammatory drugs are contraindicated in the management of this illness.
B. Corneal involvement is unlikely.
C. Cool compresses should be used.
D. Bilateral eye involvement is uncommon.
E. This highly contagious illness is most often caused by Staphylococcus aureus.
5. A 2-year-old child is brought to the office with a 3-month history of “uneven eyes.” Physical examination shows right eye exotropia and leukocoria. Computed tomography of the orbit reveals a large retinoblastoma that involves the macula. Which of the following statements regarding the diagnosis is most correct?
A. This tumor occurs sporadically and is not inherited.
B. Computed tomography reveals calcifications within the tumor.
C. Strabismus is uncommon at presentation.
D. Radiation therapy is effective and has few complications.
E. The age at diagnosis is unusual.
6. A 10-year-old girl is brought to the emergency department after sustaining a baseball injury to

the right eye. Which of the following signs or symptoms is most consistent with the suspected diagnosis of a fracture of the orbital floor?
A. Glaucoma
B. Exophthalmos
C. Diplopia
D. Numbness of the lower teeth and chin
E. Hyphema

The response options for statements 7–10 are the same. You will be required to select one answer for each statement in the set.

A. Chemical conjunctivitis
B. Conjunctivitis caused by Neisseria gonorrhoeae
C. Conjunctivitis caused by Chlamydia trachomatis
D. Conjunctivitis caused by herpes simplex virus

For each patient, select the most likely diagnosis.

1. A 7-day-old male infant with purulent conjunctival discharge and mild lid swelling.
2. A 12-hour-old male infant with bilateral watery conjunctival discharge.
3. A 10-day-old female infant with unilateral serous conjunctival discharge and multinucleated giant cells on Gram stain.
4. A 2-day-old female infant with purulent eye discharge and eyelid swelling.

Answers and Explanations
1. The answer is B [VIII.A and I.A]. Presentation with a lens opacity is consistent with a congenital cataract, a potentially very serious opacity of the lens. Immediate referral to a pediatric ophthalmologist is warranted. Surgery should occur within the first several weeks of life to ensure a good prognosis. If an opacity is not removed promptly in a young infant, the retina and nervous connections are not appropriately stimulated, and amblyopia (poor vision caused by abnormal retinal stimulation) may develop. Children are most susceptible to amblyopia during the first 3–4 months of life. Congenital cataracts are present at birth. The majority of cataracts are idiopathic, although known causes include trauma, metabolic abnormalities like galactosemia, genetic syndromes, and nonsyndromic genetic inheritance. The Bruckner test, which is used in the assessment of the bilateral red reflex, is usually abnormal in the presence of a cataract.
2. The answer is B [III.B.2.a.(2) and III.B.3.c]. Itching is the hallmark of allergic conjunctivitis, the likely cause of this patient’s symptoms. Symptoms and signs of allergic conjunctivitis also include conjunctival erythema and watery or mucoid discharge. Management includes topical antihistamines, topical mast cell stabilizers, and environmental modification (removing from the environment any known or suspected allergens such as stuffed animals, pets, or carpet). Allergic conjunctivitis is a type 1 hypersensitivity reaction and is commonly seasonal. Uncomplicated allergic conjunctivitis is not associated with bacterial infection. Other signs and symptoms of allergy are commonly found, including allergic rhinitis. Topical antibiotics are ineffective for allergic conjunctivitis.
3. The answer is A [III.B.2.a.(3) and V.B.5.c]. Conjunctivitis associated with contact lens use suggests three major possibilities, including an allergy to the contact lens solution, a corneal abrasion, or a bacterial corneal ulcer, which can be vision-threatening. A possible corneal ulcer requires urgent ophthalmologic consultation. Viral conjunctivitis is unlikely because of the acuity of the presentation, the unilateral findings, and severe photophobia. Eosinophils on conjunctival scraping are found in allergic conjunctivitis. A corneal ulcer usually appears on fluorescein staining. Because a corneal ulcer is a possibility, prescribing antibiotics with
follow-up in a week would risk missing the early diagnosis of this serious condition.
4. The answer is C [III.B.3.b.(1)]. This patient’s signs and symptoms are consistent with pharyngoconjunctival fever, a highly contagious illness that lasts for 2–3 weeks and is best managed with supportive care, including topical nonsteroidal anti-inflammatory drugs and cool compresses. Corneal involvement does occur and usually manifests as a foreign body sensation within the eye. Pharyngoconjunctival fever is commonly bilateral. It is a highly contagious illness caused by infection with adenovirus. The presence of preauricular adenopathy and watery discharge is inconsistent with bacterial conjunctivitis.
5. The answer is B [VIII.B]. Retinoblastoma is diagnosed on the basis of visual inspection and imaging studies, such as computed tomography or ocular ultrasound. Calcification within the tumor is a hallmark of retinoblastoma. Retinoblastoma is inherited sporadically or in an autosomal recessive fashion. The two most common presenting features are leukocoria (white light reflex) and strabismus. Management of large tumors often includes enucleation, although small retinoblastomas may be managed with external beam radiation. The side effects of radiation therapy include induction of secondary tumors. The majority of children with retinoblastoma are younger than 5 years.
6. The answer is C [V.D.2]. Orbital floor fracture, or a “blow-out” fracture, is generally secondary to blunt trauma to the orbit and can lead to entrapment of orbital fat and the inferior rectus muscle within the fracture. Glaucoma is typically not a complication of an orbital floor fracture. Entrapment leads to enophthalmos (i.e., retracted globe), restricted

vertical movement of the eye, and strabismus with resultant double vision (diplopia). Because the infraorbital nerve may be injured, numbness of the cheek and upper teeth may result.
Hyphema, or blood within the anterior chamber, also occurs secondary to blunt trauma. Hyphema should certainly increase your index of suspicion for other injuries associated with blunt trauma, but hyphemas frequently occur without concurrent injuries to the orbital floor.
7. The correct answers are C, A, D, and B, respectively [III.A.1–3 and Table 18-2]. Neonatal conjunctivitis is defined as conjunctivitis occurring within the first month of life. Chlamydia trachomatis causes serous or purulent conjunctivitis with variable lid swelling in infants between 4 and 10 days of age (question 7). Conjunctivitis within the first 24 hours (question 8) is characteristic of chemical irritation from neonatal prophylactic drops or ointment, such as 1% silver nitrate. Herpes simplex virus presents with vesicles, corneal ulcers, and multinucleated giant cells on Gram stain of conjunctival cells (question 9). Neisseria gonorrhoeae causes purulent, rapid onset conjunctivitis with lid swelling in infants between 2 and 4 days of age (question 10).