The Massachusetts General Hospital Handbook of Neurology

Authors: Flaherty, Alice W.; Rost, Natalia S.

Title: Massachusetts General Hospital Handbook of Neurology, The, 2nd Edition

Copyright 2007 Lippincott Williams & Wilkins

> Table of Contents > Child Neurology > Eyes and Vision

Eyes and Vision

A. See also

Adult Eyes and Vision, p. 44.

B. Nystagmus

• Congenital nystagmus: Begins at age 2-3 mo, not at birth. Pts. do not feel spinning vertigo but sometimes have poor acuity.

• Spasmus nutans: Nystagmus with head nodding and abnormal head position. Onset 6-12 mo, lasts 1-2 yr, improves spontaneously.

C. Oculomotor palsy

• H&P: Babies >3 mo old should have conjugate gaze and good fixation. See adult eye movements, p. 46, for exam (although you will probably need something more interesting than your finger to get a 2-year-old to track).

• Causes: Causes also seen in adults include raised ICP, tumor, aneurysm, thrombosis, myasthenia, trauma, orbital entrapment, mitochondrial dz, etc. Additional pediatric causes include:

  • Infantile botulism: Hypotonia with big, sluggish pupils, ANS dysfunction. May see ptosis without ophthalmoplegia. Associated with eating honey. Unlike adult form, spores colonize gut. Antitoxin and antibiotics do not help.

  • Congenital palsies: Duane's syndrome (poor ab- or adduction with globe retraction), M bius syndrome (bilateral 6th and 7th palsies), Brown syndrome (congenitally short superior oblique muscle), congenital myasthenia.

  • Infection: E.g., meningitis, Gradenigo's syndrome (petrous inflammation).

  • Ophthalmoplegic migraine: Sx begin during or just before a migraine but may last up to 1 mo. Oculomotor nerve is affected in 80%.

D. Strabismus

Nonparalytic ocular misalignment. If constant and persistent, child will often fixate only with one eye, develop amblyopia (loss of acuity) in the other, and have no complaint of diplopia.

• H&P: If misalignment is fixed, test EOM monocularly to r/o paralysis. If it is intermittent, perform alternating cover test, p. 48. Test acuity, fundus exam.

• Rx: Alternate patching of the eyes. Corrective surgery. Botulinum toxin has recently been tried.

E. Visual loss

• H&P: In babies, test pupillary, red, and blink reflex. By 6 wk, babies should make and maintain eye contact. Babies under 3 mo should only be expected to fix and follow. Babies over 3 mo should have conjugate gaze and a visual grasp, but the latter is hard to test before 6 mo. Look

  P.137

  for abnormal eye movements, structural abnormalities such as cataracts, fundal lesions, microphthalmia.

• Tests: Visual evoked responses should be present by 30 wk gestation and mature at 3 mo.

• Causes: See causes also seen in adults (retinal ischemia, optic nerve or cortical lesions, etc.), p. 44.

  • Acute: Carotid dissection, ICH, hysteria, migraine, optic neuropathy (demyelinating, ischemic, toxic), pseudotumor cerebri, trauma.

  • Subacute or chronic:

    • Compression: Tumor, aneurysm, AVM, inflammatory mass.

    • Cataracts: Genetic, intrauterine drug exposure (chlorpromazine, steroids, sulfonamides) or infection (mumps, rubella, syphilis), prematurity, endocrine abnormalities, trauma, postnatal varicella. Remove cataracts before 3 mo to prevent amblyopia.

    • Hereditary optic atrophies: Sometimes isolated. Multisystem involvement is most often mitochondrial dz.

    • Tapetoretinal degeneration: Usually disorders of carbohydrate or lipid metabolism, and associated with dementia, neuropathy, and ataxia.

  • Other: Congenital optic nerve hypoplasia, coloboma (an embryonic retinal defect), Leber's congenital amaurosis (unrelated to the mitochondrial disorder of Leber's hereditary optic neuropathy), dislocated lens, corneal clouding (e.g., in mucopolysaccharidosis and Fabry's dz).