NYSTAGMUS/IATROGENIC PROBLEMS
From Diagnosis and Management in Pediatric Ophthalmology and Neuro-Ophthalmology, presented June 3-4, 2005,
by the University of Michigan Medical School, Department of Ophthalmology and Visual Sciences, and the American
Association of Certified Orthoptists
| NYSTAGMUS SURPRISES IN CHILDREN —Creig S. Hoyt, MD, Professor and Chairman, Department of Ophthalmology,
University of California, San Francisco, School of Medicine
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| Age of onset: case—boy, 5 mo of age, with asymmetric horizontal nystagmus; symptoms began at ≈4 mo of age; no other
remarkable findings; child initially diagnosed with spasmus nutans; problem—spasmus nutans never occurs in children
<6 mo of age; age of onset rules out spasmus nutans, even though presentation suggestive; work-up—magnetic resonance
imaging (MRI) important to rule out lesion (eg, glioma) affecting afferent visual pathway
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| Amplitude and frequency: case—infant, 9 mo of age, with symmetric nystagmus with small amplitude and fast frequency;
symptoms began at ≈3 mo of age; patient became photophobic at 6 mo of age; examination yielded no other findings;
differential—cone disorders (especially achromatopsia); spasmus nutans; optic nerve glioma; delayed photophobia
(commonly presenting at 6-8 mo of age) associated with cone dystrophies; photophobia initially severe, then subsides
with age; diagnosis—cone dystrophy; achromatopsia and blue cone dystrophy present within first year of life
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| Congenital nystagmus: 99% of cases have sensory etiology, unless family history of motor nystagmus documented;
case—girl, 6 yr of age, presents with symmetric horizontal nystagmus; child initially diagnosed with congenital motor
nystagmus; testing revealed visual acuity of 20/200 (inconsistent with diagnosis); nystagmus has small amplitude and fast
frequency; electroretinography (ERG) revealed achromatopsia
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| Asymptomatic retinal disorders: Leber’s amaurosis, cone dystrophies, and x-linked recessive stationary night blindness
and myopia not associated with ophthalmic abnormalities in young patients; important to consider retinal disease in children
with nystagmus; ERG or MRI often recommended
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| Retinoscopy: essential for diagnosis of children with congenital nystagmus; myopia—rare in nonsyndromic infants <4 mo
of age; suggestive of x-linked stationary night blindness or blue cone dystrophy; hyperopia—generally indicative of
Leber’s amaurosis (congenital cone-rod dystrophy); astigmatism—commonly occurs in young patients with retinal disease
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| Direction of nystagmus: children with retinal disease commonly present with upbeat nystagmus in first few months of life;
direction then changes to horizontal nystagmus, typically by 2 yr of age
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| Conditions mimicking congenital sensory nystagmus: raised intracranial pressure and tumors affecting optic nerve may
present as congenital sensory nystagmus; case—boy, 6 mo of age, with symmetric nystagmus in horizontal direction
(onset at 2 mo of age), Apgar scores of 5 and 9, and symmetric optic atrophy; child initially diagnosed with optic atrophy
secondary to hypoxia; problems—Apgar scores inconsistent with diagnosis; child has no other neurologic findings; additional
work-up—MRI showed elevated intracranial pressure and x-linked kinking of aqueduct
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| Spasmus nutans: rare disorder; asymmetric nystagmus in young children may become symmetric over time (ie, early diagnosis
of spasmus nutans often incorrect); follow-up important
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| Nystagmus and strabismus: large-angle horizontal strabismus—deviation \>10 to 15 prism diopters in full-term infants
with congenital nystagmus generally indicates benign condition, especially when both eyes fixate equally; albino
patients—associated strabismus generally has small angle; congenital sensory nystagmus—significant strabismus
rare, except in patients with asymmetric optic nerve disease; premature infants—≈50% of patients with periventricular
leukomalacia develop nystagmus and strabismus (related to degree of involvement of corpus callosum)
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| Monocular loss of vision during infancy: nystagmus often delayed; binocular nystagmus—patients turn face and have
strong preference of fixation in unaffected eye; nystagmus may compromise visual acuity; monocular nystagmus—
common in patients with severe amblyopia; overall, much less common than binocular nystagmus
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| NEW-ONSET NYSTAGMUS IN ADULTS —Nicholas J. Volpe, MD, Associate Professor of Ophthalmology and Neurology,
Scheie Eye Institute, University of Pennsylvania, Philadelphia
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| Eye movements: nystagmus—defects of slow-pursuit eye movement; saccadic oscillations—defects in fast saccade eye
movement; oscillopsia—perceived visual jumping of environment; patients often complain of double vision, blurred vision,
or general unsteadiness; symptoms associated with nystagmus—peripheral vestibular problems include tinnitus,
hearing loss, nausea, and vomiting; brainstem symptoms include dysarthria, diplopia, facial nerve symptoms, and dysphagia
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| History: presence of temporal features or associated symptoms; description of vision; medication use; history of systemic
illness or neurologic conditions
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| Examination: look for duction, versions, and abnormalities in saccades or pursuit system (central localization may aid in diagnosis);
elicit vestibular ocular reflex (nystagmus induced by rapid movement of head suggests vestibular lesion); check
for optokinetic nystagmus by asking patient to maintain visual fixation on thumb while chair rotates; note direction of
gaze; look for changes in nystagmus with occlusion; assess movements of disc and fundus; note speed and direction of eye
movements; perform vestibular testing (eg, Dix-Hallpike maneuver and caloric tests) to check for peripheral vestibular disease
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| General rules: peripheral disease—eg, acoustic neuromas, inner ear problems; unidirectional nystagmus (dependent on
location of lesion), typically inhibited by fixation; horizontal movement, sometimes with torsional component, and always
jerk form; central disease—eg, multiple sclerosis (MS), tumors, and other cerebellar problems; direction changes
with gaze (left and right); nystagmus not usually inhibited with fixation; jerk and pendular forms; nystagmus may mimic
peripheral pattern, depending on location of lesion
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| Pathologic gaze-evoked nystagmus: amplitude usually \>4°; asymmetry occurs, but direction stable; rebound may occur
after maintaining fixation in direction of nystagmus; medications (eg, phenytoin [Dilantin]) often responsible
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| Bruns’ nystagmus: characteristic of cerebellopontine angle tumors; nystagmus varies with direction of gaze; gaze-evoked
nystagmus with high amplitude occurs when patient looks in direction of lesion; nystagmus with low amplitude and high
frequency occurs when patient looks in opposite direction
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| Dissociated nystagmus: patients with internuclear ophthalmoplegia have form of gaze-evoked nystagmus; paresis results in
dampened movements in adducting eye; nystagmus may predominate
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| Periodic alternating nystagmus: unusual type of jerk nystagmus that changes direction and has fluctuating null point; congenital
and acquired forms (concern about lesions in central cervicomedullary junction and in cerebellum); vision loss
may occur; treatment with baclofen often successful; work-up in adult patient same as in patient with downbeat nystagmus
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| Downbeat nystagmus: presentation includes blurred vision, double vision, and difficulty reading; nystagmus often not detected;
symptoms elicited with lateral gaze; adverse effect associated with lithium, carbamazepine (Tegretol), and others;
other etiologies include magnesium deficiency and paraneoplastic syndrome; abnormalities occur at cervicomedullary
junction (eg, Arnold-Chiari malformation); correcting structural abnormality may eliminate nystagmus; prism therapy
may induce convergence; shifting gaze away from symptomatic field may help; drug-induced form may improve or resolve
when patients taken off drug
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| Upbeat nystagmus: often seen in patients with bilateral internuclear ophthalmoplegia or pontomedullary, pontomesencephalic,
or cerebellar lesions
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| Oculopalatal myoclonus: delayed onset, often after stroke or traumatic injury to brain; rhythmic movements (3 Hz; vertical,
horizontal, or elliptical) that persist during sleep; etiologies include olivary hypertrophy and lesion in area of red nucleus,
inferior olive, and dentate nucleus; severe injuries may result in inability to evoke symptoms; pendular movements
(at same frequency as eye movements) occur in palate and sometimes in face, shoulders, and elsewhere
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| Oculomasticatory myorrhythmia: divergence-convergence nystagmus characteristic of Whipple’s disease; similar contractions
occur in masticatory muscles and sometimes shoulders; condition likely associated with abnormality of midbrain; eye
movements in horizontal plane unaffected, but complete supranuclear gaze palsy occurs when patient looks up
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| Seesaw nystagmus: rare condition, usually seen in young patient with history of significant chiasmal lesion or tumor (eg,
craniopharyngioma); elevation and intorsion in one eye and depression and extorsion in other eye (torsion sometimes reversed
in congenital forms); congenital forms include unusual pigmentary retinopathies and achiasmia; acquired forms
include sellar or midbrain lesions; movements often more severe in one eye
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| Convergence-retraction nystagmus: not true nystagmus; gaze palsy in patient with dorsal midbrain syndrome prevents
upward gaze; patient contracts facial muscles in attempt to pull eyes up; other features of dorsal midbrain syndrome include
abnormalities in pupils and retraction of eyelids; diagnosis of hydrocephalus or pinealoma
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| Congenital motor nystagmus: absence of oscillopsia; null point occurs; nystagmus dampens with convergence; direction
remains horizontal in upgaze (unique feature); patients have reverse optokinetic response
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| Latent nystagmus: nystagmus occurs when one eye occluded; beating directed away from covered eye (covering opposite
eye changes direction of nystagmus); patients have history of strabismus
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| Saccadic oscillations: flutter, opsoclonus, and square-wave jerks (may occur as part of progressive supranuclear palsy);
slow phase absent; square-wave jerk has small intersaccadic interval; other classic cerebellar eye signs (eg, dysmetria and
macrosaccadic oscillations) often present; patients with encephalitis or paraneoplastic process affecting cerebellum may
present with opsoclonus or flutter; flutter characterized by repeated saccades with no saccadic interval, movements only
in horizontal plane; opsoclonus includes vertical movements, and often associated with diffuse injury to brain (eg, hypoxia,
encephalitis, toxic injury)
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| Superior oblique myokymia: characteristic presentation includes monocular oscillopsia with vertical double vision; condition
sometimes confused with eyelid myokymia; MS or lesion in midbrain may be cause; treatment includes gabapentin
(Neurontin), Tegretol, topical β-blockers, and superior oblique tenectomy with inferior oblique myotomy; examination
with slit lamp shows irregular vibratory movements; symptoms may subside for weeks
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| Voluntary nystagmus: can be produced on command; movement usually sustained for several seconds
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| MEDICATION-INDUCED VISION LOSS —Wayne T. Cornblath, MD, Clinical Professor, Departments of Ophthalmology
and Visual Sciences and Neurology, University of Michigan, Ann Arbor
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| Medication toxicity: drugs known to have adverse effects on vision include digoxin, prednisone (cataracts and increased intraocular
pressure [IOP]), and tetracycline (pseudotumor cerebri); criteria—adverse reaction frequent and well-documented;
recovery usually occurs after withdrawal of medication; other causes eliminated; reaction related to dose; objective evidence
of effect; similar effects occur with similar drugs; event occurs with subsequent challenge; medication toxicity implicated
when ≥5 criteria met
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| Lacrimal glands: reduction in production of tears or abnormalities in tear film lead to dry eyes
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| Cornea: deposits may result in glare, halos, blur, or photophobia; amiodarone thought to deposit lipids; chlorpromazine deposits
pigment
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| Lens: cataracts or deposits result in blur, glare, halos, or monocular diplopia; tamoxifen and steroids may cause formation
of cataracts
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| Ciliary body: elevated IOP or angle closure may result; prednisone commonly raises IOP; topiramate (Topamax) may cause
glaucoma through ciliochoroidal effusion and angle closure
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| Retina: deposits; toxicity of photoreceptors or retinal pigment epithelium (RPE); effects include change in color, decreased
acuity, photopsia, and scotoma; hydroxychloroquine (Plaquenil) causes “bull’s eye”; tamoxifen may produce crystalline-
like deposits; sildenafil (Viagra) causes temporary blue vision (ERG decreases by 40%, then recovers); reports of optic neuropathy
attributed to Viagra likely related to microvascular disease in these patients rather than medication toxicity
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| Optic neuropathy: Plaquenil—published recommendations list low-risk and high-risk features that affect frequency of
screening; optic neuropathy affects acuity and color and produces scotoma; localization—amiodarone causes anterior
optic neuropathy; Plaquenil and ethambutol cause retrobulbar optic neuropathy; note—optic neuropathy reported in patients
taking <15 mg/kg of ethambutol (recommended dose to avoid adverse effects); secondary (nonidiopathic) pseudotumor
cerebri—associated with tetracycline, minocycline, doxycycline, and isotretinoin (Accutane)
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| Ocular motility: ophthalmoplegia or myasthenic syndrome (variable diplopia); medications include phenytoin (Dilantin),
atorvastatin (Lipitor), and other drugs that lower cholesterol
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| Occipital lobe: patients who develop posterior reversible encephalopathy syndrome (PRESS) have cortical vision loss (predominant
feature) and confusion, but no other neurologic features; MRI shows typical bilateral changes in occipital lobe
(possibly asymmetric); cyclosporine and several chemotherapeutic agents implicated
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| Resources: Toxicology of the Eye (Grant and Schuman); Drug-Induced Ocular Side Effects (Fraunfelder and Fraunfelder)
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Educational Objectives
| The goal of this activity is to review clinical and diagnostic features of nystagmus and provide information about ocular adverse
effects associated with common medications. After hearing and assimilating this program, the clinician will be better
able to:
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 | 1. Discuss relative importance of age, family history, and clinical features in diagnosing infants with nystagmus.
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| 2. Diagnose and treat children with nystagmus.
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| 3. Diagnose and treat patients with adult-onset nystagmus.
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| 4. Discuss key features of common forms of adult-onset nystagmus.
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| 5. Recognize medication-induced ophthalmic conditions.
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Discussed on This Program
Amiodarone HCl [ Cordarone, Pacerone]
Atorvastatin calcium [Lipitor]
Baclofen [Lioresal, Lioresal Intrathecal]
Carbamazepine [Atretol, Carbatrol, Epitol, Tegretol, Tegretol-XR]
Chlorpromazine HCl [Thorazine, Thorazine Spansules]
Cyclosporine (cyclosporin A) [Neoral, Sandimmune, SangCya]Digoxin [Digitek, Lanoxicaps, Lanoxin]
Doxycycline [Adoxa, Atridox Injection, Bio-Tab, Doryx, Doxy 100, Doxy 200, Doxy Caps, Doxychel Hyclate, Monodox,
Periostat, Vibramycin, Vibramycin IV, Vibra-Tabs]
Ethambutol hydrochloride [Myambutol]
Gabapentin [Neurontin]
Hydroxychloroquine sulfate [Plaquenil, Plaquenil Sulfate] Isotretinoin [Accutane]
Lithium [Eskalith, Eskalith CR, Lithium Carbonate, Lithium Citrate, Lithobid, Lithonate, Lithotabs]
Minocycline HCl (minomycin) [Arestin, Dynacin, Minocin, Minocin IV, Vectrin]
Phenytoin sodium [Dilantin]
Prednisone (several trade names)
Sildenafil citrate [Viagra]
Tamoxifen citrate [Nolvadex]
Tetracycline HCl [Achromycin V, Actisite, Ala-Tet, Nor-tet, Panmycin, Robitet Robicaps, Sumycin, Teline, Tetracap,
Tetracyn Tetralan, Tetram, Topicycline]
Topiramate [Topamax]
Suggested Reading
Almony A, et al: Threshold Amsler grid as a screening tool for asymptomatic patients on hydroxychloroquine therapy. Br
J Ophthalmol 89:569, 2005; Brodsky MC: Visuo-vestibular eye movements: infantile strabismus in three dimensions.
Arch Ophthalmol 123:837, 2005; Hadjikoutis S, et al: Ocular complications of neurological therapy. Eur J Neurol
12:499, 2005; Hertle RW, et al: Horizontal rectus muscle tenotomy in children with infantile nystagmus syndrome: a pilot
study. J AAPOS 8:539, 2004; Koksal M, et al: The effects of sildenafil on ocular blood flow. Acta Ophthalmol Scan
83:355, 2005; Leung S, et al: Bisphosphonate-associated scleritis: a case report and review. South Med J 98:733, 2005;
Lopez C, et al: Torsional optokinetic nystagmus after unilateral vestibular loss: asymmetry and compensation. Brain
128:1511, 2005; Marmor MF, et al: Recommendations on screening for chloroquine and hydroxychloroquine retinopathy:
a report by the American Academy of Ophthalmology. Ophthalmology 109:1377, 2002; Meyer CH, et al: Optical coherence
tomography in children. Am J Ophthalmol 140:167, 2005; Salman MS, et al: Saccades in children with spina bifida
and Chiari type II formation. Neurology 64:2098, 2005; Sampangi R, et al: Cone-rod dystrophy and acquired dissociated
vertical nystagmus. J Pediatr Ophthalmol Strabismus 42:114, 2005; Sandramouli S, et al: See-saw nystagmus as the presenting
sign in multiple sclerosis. J Neuroophthlamol 25:56, 2005; Tilikete C, et al: Anti-GAD antibodies and periodic alternating
nystagmus. Arch Neurol 62:1300, 2005; Tkalcevic LA, Abel LA: The effects of increased visual task demand on
foveation in congenital nystagmus. Vision Res 45:1139, 2005; Yang D, et al: Gaze-dependent and time-restricted visual
acuity measures in patients with Infantile Nystagmus Syndrome (INS). Am J Ophthalmol 139:716, 2005.
Faculty Disclosure
In adherence with ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. For this issue, the faculty
reported nothing to disclose.
Drs. Cornblath, Hoyt, and Volpe were recorded in Ann Arbor at Diagnosis and Management in Pediatric Ophthalmology
and Neuro-Ophthalmology, sponsored by the University of Michigan Medical School, Department of Ophthalmology
and Visual Sciences, and the American Association of Certified Orthoptists, and held June 3-4, 2005. The
Audio-Digest Foundation thanks the speakers and the sponsors for their cooperation in the production of this program.
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