Nystagmus

Nystagmus is a condition of involuntary (or voluntary, in some cases)eye movement, acquired in infancy or later in life, that in extremely rare cases may result in reduced or limited vision. Due to the involuntary movement of the eye, it has been called "dancing eyes"Contents

1 Causes
1.1 Early-onset nystagmus
1.2 Acquired nystagmus
1.3 Other causes
2 Diagnosis
2.1 Pathologic nystagmus
2.2 Physiological nystagmus
3 Treatment
4 Epidemiology

1. Amr Hassan, MD, FEBN
Professor of Neurology -Cairo University
Nystagmus

2. AGENDA
•3
rd
,4
th
, 6
th
nerves
•Extraocularmuscles
•How to examine for ocular motility
•Ophthalmoplegia
•Diplopia and related disorders
•Gaze pathway
•How to examine for gaze
•Gaze palsy
•Types of eye movements
•How to examine for EM
•Nystagmusand non nystagmusocular oscillation

3. AGENDA
•3
rd
,4
th
, 6
th
nerves
•Extraocularmuscles
•How to examine for ocular motility
•Ophthalmoplegia
•Diplopia and related disorders
•Gaze pathway
•How to examine for gaze
•Gaze palsy
•Types of eye movements
•How to examine for EM
•Nystagmusand non nystagmusocular oscillation

4. Eye movements
Centrescontrolling the nuclei –Supranuclear
Pathways connecting the nuclei –Internuclear
Nerves supplying the EOM -Infranuclear

5. FAST EYE MOVEMENTS
(300°-600°/SEC)
1) SACCADES
2) NYSTAGMUS
SLOW EYE MOVEMENTS
(5°-50°/SEC)
1)SMOOTH PURSUIT
2) OPTOKINETIC
3) VESTIBULAR
4) VERGENCE
Eye movements

6. •Allows bifoveationof an object.
•Stimuli –
✓Retinal blur –accomodativevergence.
✓Disparity of location of images-fusional
vergence.
•Pathway : Occipital cortex –midbrain reticular
formation –3rd nerve nucleus
Vergence

7. How the eyes move?

8. Pulse –step theory

9. Pulse –step theory

10. Pulse –step theory

11. Pulse –step theory

12. Disorders of Saccades

13. Nystagmus: Pathological anatomy

14. Nystagmus: Pathological anatomy

15. Nystagmus

16. •Nystagmusis a repetitive, involuntary, to-and-fro
oscillation of the eyes, which may be physiological or
pathological.
•Ocular movements that bring about fixation on an
object of interest are called foveatingand those that
move the fovea away from the object are defoveating.
Nystagmus: Definition

17. •In pathological nystagmus, each cycle of movement is
usually initiated by :
✓an involuntary, defoveatingdrift of the eye away
from the object of interest
✓followed by a returning refixationsaccadic
movement.
Nystagmus: Definition

18. Nystagmus: Overview

19. ❑The plane of nystagmusmay be horizontal, vertical,
torsional or non-specific.
❑The amplitude of nystagmusrefers to how far the eyes
move (fine or coarse)
❑The frequency refers to how rapidly the eyes oscillate
(high, moderate or low).
Nystagmus: Metrics

20. Nystagmus: Degree

21. ❑Jerknystagmus
•Saccadic with a slow defoveating‘drift’ movement
and a fast corrective refoveatingsaccadic movement.
•The direction of nystagmusis described in terms of
the direction of the fast component.
Nystagmus: Morphology

22. ❑Pendularnystagmus
•Non-saccadic in that both the foveatingand
defoveatingmovements are slow.
(i.e. the velocity of nystagmusis equal in both
directions).
Nystagmus: Morphology

23. Jerky Nystagmus

24. PendularNystagmus

25. ❑Mixednystagmusinvolves pendularnystagmusin the
primary position and jerk nystagmuson lateral gaze.
Nystagmus: Morphology

26. Movement:
Pendular
Jerk
Mixed
Plane: Horizontal, vertical, torsional, or combination
Amplitude: amount of excursion
Frequency: cycles per time unit
Manifestation: manifest, latent, manifest-latent
Degree: 1
st
, 2
nd
, 3
rd
Nystagmus: Description

28. EPN
VOR
OKN
Physiological Nystagmus

29. End-point nystagmus
•Fine jerk nystagmusof moderate frequency found when
the eyes are in extreme positions of gaze.
•Fast phase is in the direction of gaze.
Physiological Nystagmus: EPN

30. •OKNis a jerk nystagmusinduced by moving repetitive
targets across the visual field.
•The slow phase is a pursuit movement in which the eyes
follow the target; the fast phase is a saccadic movement
in the opposite direction as the eyes fixate on the next
target.
•OKNis useful for detecting malingerers who feign
blindness and for testing visual acuity in the very young.
Physiological Nystagmus: OKN

31. Physiological Nystagmus: OKN

32. •Turning the drum to the right elicits an
ipsilateralpursuit movement to the right and a
contralateral saccade to the left.
Physiological Nystagmus: OKN

33. •Jerk nystagmuscaused by altered input from
the vestibular nuclei to the horizontal gaze
centres
Physiological Nystagmus: VOR

34. •‘COWS’(cold-opposite,warm-same)
Physiological Nystagmus: VOR

35. •Whencoldwaterispouredintobothears
simultaneously,ajerknystagmuswiththefast
phaseupwardsdevelops.
•Warmwaterinbothearselicitsnystagmus
withthefastphasedownwards
نواد يفاد
Physiological Nystagmus: VOR

36. Physiological Nystagmus: VOR

38. Infantile Nystagmus

41. Infantile Nystagmus

42. Spasmasnutans

43. •Presentationof this rare condition is between 3
and 18 months.
•Idiopathic which spontaneously resolves by age 3
years.
•Gliomaof anterior visual pathway, empty sella
syndrome and porencephaliccyst.
Spasmasnutans

44. •Unilateral or bilateral small-amplitude high-
frequency horizontal nystagmusassociated with
head nodding.
•It is frequently asymmetrical with increased
amplitude in abduction.
•Vertical and torsional components may be
present.
Spasmasnutans

45. Spasmasnutans

46. Nystagmusblockage syndrome

47. •Latent nystagmusis associated with infantile
esotropia
•With both eyes open there is no nystagmus.
Horizontal nystagmusbecomes apparent on
covering one eye or reducing the amount of light
reaching the eye.
•Fast phase is in the direction of the uncovered
fixating eye.
Latent nystagmus

48. •Occasionally, an element of latency may be
superimposed on a manifest nystagmusso that
when one eye is covered the amplitude of
nystagmus increases.
Manifest-latent nystagmus

50. Acquired Nystagmus: classification

51. Peripheral vestibular nystagmusis caused by disease
affecting the ear such as:
✓Labrynthitis
✓Ménière'sdisease
✓Middle or inner ear infections.
Vestibular Nystagmus

52. Vestibular Nystagmus

53. Central VsPeripheral Nystagmus

54. Downbeat nystagmus

55. •Vertical nystagmuswith the fast phase beating downwards,
which is more easily elicited in lateral gaze and downgaze.
•Causes
•Lesions of the craniocervicaljunction at the foramen
magnum such as Arnold–Chiarimalformation and
syringobulbia.
•Drugs such as lithium, phenytoin, carbamazepineand
barbiturates.
•Wernickeencephalopathy, demyelinationand
hydrocephalus.
Downbeat nystagmus

56. Upbeat Nystagmus

57. •Vertical nystagmuswith the fast phase beating
upwards
•Causes include posterior fossa lesions, drugs
and Wernicke encephalopathy.
Upbeat Nystagmus

58. Ataxic Nystagmus

59. Looking to RIGHT
Nystagmuson abducting eye
Failure of adduction with NORMAL III
Cr.N
:
INO:InternuclearOphthalmoplegia

60. INO :MLF Lesion

61. •Demyelination
•Vascular disease
•Tumoursof the brainstem and 4th ventricle
•Trauma
•Encephalitis
•Hydrocephalus
•Progressive supranuclearpalsy
•Drug-induced
•Miller fisher syndrome
• Wernicks’ encephalopathy
INO : Causes

62. Periodic alternating nystagmus

63. Periodic alternating nystagmus
•Conjugate horizontal jerk nystagmusthat periodically reverses
its direction.
•Each cycle may be divided into active and quiescent phases as
follows:
✓During the active phase, the amplitude, frequency and slow-
phase velocity of nystagmusfirst progressively increase then
decrease.
✓This is followed by a short, quiet interlude, lasting 4–20 sec,
during which time the eyes are steady and show low-intensity,
often pendularmovements.
✓A similar sequence in the opposite direction occurs thereafter,
the whole cycle lasting between 1 and 3 minutes.

64. Periodic alternating nystagmus
Causesinclude
•Isolated congenital
•Cerebellar disease
•Ataxia telangiectasia (louis–bar syndrome)
•Drugs such as phenytoin.

65. Convergence-retraction nystagmus

66. •It is the result of co-contraction of the
extraocularmuscles, particularly the medial
recti followed by a slow divergent movement.
•Associated retractionof the globe into the
orbit.
•Causesinclude lesions of the pretectalarea
such as pinealomaand vascular accidents
(Parinauddorsal midbrain syndrome).
Convergence-retraction nystagmus

67. Brunsnystagmus

68. •Coarse cerebellar horizontal jerk nystagmusin
one eye and fine high frequency vestibular
nystagmusin the other.
•CPA tumourssuch as acoustic neuroma. The
lesion is ipsilateralto the side with coarse
cerebellar nystagmus.
Brunsnystagmus

69. 69

70. •Voluntary nystagmusis not true nystagmus
but ocular flutter under voluntary control.
•It consists of a series of fast (saccadic) back-to-
back eye movements, without any interval or
slow phase.
•The oscillations usually are horizontal but may
be vertical, torsional, or (rarely) cycloid—a
phenomenon reported as “volitional
opsoclonus” or multiplanarflutter.
Voluntary nystagmus

71. •The ability to induce flutter voluntarily tends
to be familial.
•Usually, persons with this ability must
converge their eyes to initiate the oscillation
but are unable to sustain it for longer than 30
seconds.
Voluntary nystagmus

72. 72

75. Non Nystagmusocular oscillation

76. Opsoclonus

77. •Opsoclonusis a spontaneous, chaotic,
multivectorsaccadic eye movement disorder
in which the abnormal movements are
virtually always conjugate.
•Opsoclonusis aggravated by attempts at
fixation
•It may be associated with myoclonic jerks of
the limbs and cerebellar ataxia (dancing eyes–
dancing feet syndrome).
Opsoclonus

78. •Dysfunction of the pause cells in the pons due
to cerebellar or brainstem disease is the
cause.
•The most common causes are: toxic,
metabolic, and paraneoplasticdisorders.
Opsoclonus

79. Ocular Flutter

80. •Ocular flutter consists of horizontal conjugate
back-to back saccades that occur
spontaneously in intermittent bursts.
•It is aggravated by attempts at fixation.
•Occasionally it is triggered by a change in
posture.
Ocular Flutter

81. •It results from loss of pause cell inhibition of
the burst neurons in the paramedianpontine
reticular formation (PPRF), caused by injury
either to the PPRF or to the cerebellar
neurons that influence the pause cells, or
both.
•It occurs with brainstem or cerebellar disease
Ocular Flutter

82. Ocular Bobbing

83. •Ocular bobbing is a rapid downward
movement of both eyes followed by a slow
drift back to primary position.
•The oscillation recurs between 2 and 15 times
per minute
•It is found in patients (usually comatose) with
severe central pontinedestruction and
horizontal gaze palsies
Ocular Bobbing

84. Square-Wave Jerks

85. •Square-wave jerks (SWJs) are spontaneous,
small amplitude, paired saccades with an
intersaccadiclatency of 150 to 200 msecthat
briefly interrupt fixation.
•They may occur physiologically in normal
subjects (particularly in darkness) without
fixation. They are more common in the elderly.
•SWJs are prominent in PSP, multiple system
atrophy (MSA), and cerebellar disease.
Square-Wave Jerks

86. AGENDA
•3
rd
,4
th
, 6
th
nerves
•Extraocularmuscles
•How to examine for ocular motility
•Ophthalmoplegia
•Diplopia and related disorders
•Gaze pathway
•How to examine for gaze
•Gaze palsy
•Types of eye movements
•How to examine for EM
•Nystagmusand non nystagmusocular oscillation

88. Eye movements
Centrescontrolling the nuclei –Supranuclear
Pathways connecting the nuclei –Internuclear
Nerves supplying the EOM -Infranuclear

89. Eye movements
Centrescontrolling the nuclei –Supranuclear
Pathways connecting the nuclei –Internuclear
Nerves supplying the EOM -Infranuclear

90. Ptosis

91. Block the action of frontalisto differentiate between
partial and complete ptosis.
Ptosis : frontalisoveraction

92. Individual eye examination

93. Eye movements
Centrescontrolling the nuclei –Supranuclear
Pathways connecting the nuclei –Internuclear
Nerves supplying the EOM -Infranuclear

94. Eye movements
Centrescontrolling the nuclei –Supranuclear
Pathways connecting the nuclei –Internuclear
Nerves supplying the EOM -Infranuclear

95. FAST EYE MOVEMENTS
(300°-600°/SEC)
1) SACCADES
2) NYSTAGMUS
SLOW EYE MOVEMENTS
(5°-50°/SEC)
1)SMOOTH PURSUIT
2) OPTOKINETIC
3) VESTIBULAR
4) VERGENCE
Eye movements

96. How to examine for gaze

97. How to examine for gaze

98. How to examine for Saccade

99. How to examine for Pursuit

100. How to examine for Convergence

101. •Turning the drum to the right elicits an
ipsilateralpursuit movement to the right and a
contralateral saccade to the left.
Physiological Nystagmus: OKN

102. Physiological Nystagmus: VOR

103. THANK YOU
[email protected]

104. BACKUP SLIDES

105. (3) Primary congenital nystagmus:
❑Inheritanceis XLR or AD, and rarely AR.
❑Presentationis about 2–3 months after birth and persists throughout life.
Adults with congenital forms of nystagmusdo not notice oscillopsia
❑Signs
•In the primary position there is low-amplitude pendularnystagmusthat converts
to jerk nystagmuson side gaze.
•In upgazeand downgazethe nystagmusremains in the horizontal plane.
•The nystagmusmay be dampened by convergence and is not present during
sleep.
•There is usually a null point (a position of gaze) in which nystagmusis minimal.
•In order to move the eyes into the null point, an abnormal head posture may be
adopted.
Types of nystagmus

106. (3) Ocular Microflutter
❑Ocular microflutter, previously called microsaccadicocular
flutter (a redundant term), is a rare symptomatic ocular
oscillation requiring magnification for detection
❑It may be a form of opsoclonusbut in some patients is a
variant of voluntary nystagmus.
❑Patients complain of episodes of “shimmering” vision. It is
reported with cerebellardegeneration and MS.
❑When it is persistent, patients should be evaluated for occult
neoplasms.
❑Microfluttermay respond to propranololor verapamil.
Non Nystagmusocular oscillation

107. (5) Ocular Dysmetria
❑Ocular dysmetriaoccurs with refixationsaccades that
overshoot the target and often oscillate with an
intersaccadiclatency of approximately 200 milliseconds
before coming to rest
❑It results from dysfunction of dorsal vermisand fastigial
nuclei in the cerebellum.
Non Nystagmusocular oscillation

108. (7) Ocular Myoclonus(OculopalatalTremor)
❑Ocular myoclonusis a vertical pendularoscillation with a frequency of
approximately 160 Hz, usually associated with similar oscillations of the
soft palate (palatal tremor) and sometimes other muscles of branchial
origin.
❑The palatal tremor, referred to as the oculopalatalsyndrome, occurs after
brainstem infarction, particularly of the pons, involving the central
tegmentaltract
❑The association of a facial nerve palsy and the one-and-a-half syndrome
may predict the development of oculopalatalmyoclonus, probably
because of the proximity of the central tegmentaltract to the facial nerve.
❑Also, oculopalatalmyoclonuscan occur spontaneously in association with
progressive ataxia, a fourth ventricular tumor, or hydrocephalus following
subarachnoid hemorrhage
Non Nystagmusocular oscillation

109. (8) Superior Oblique Myokymia
❑Superior oblique myokymiais a paroxysmal, rapid, small
amplitude, monocular torsional-vertical oscillation caused by
contraction of the superior oblique muscle, predominantly on
the right side.
❑Patients may complain of monocular blurring, torsionalor
vertical oscillopsia, torsionalor vertical diplopia, or twitching
of the eye.
❑It is caused by injury or compression to 4
th
nerve
Non Nystagmusocular oscillation

110. (3) Wrong-Way Eyes:
➢Conjugate eye deviation to the “wrong” side—that is, away from the lesion
and toward the hemiplegia(contraversivegaze deviation)—may occur with
supratentoriallesions, particularly thalamic hemorrhage and (rarely) large
perisylvianor lobar hemorrhage.
➢The mechanism is unclear, but possibilities include the following:
1.1. An irritativeor seizure focus causing “contraversiveocular deviation” is
unlikely, because neither clinical nor electrical seizure activity has been
reported in these patients.
2.2. Because eye movements are represented bilaterally in each frontal lobe, it
is conceivable that the center for ipsilateralgaze alone may be damaged,
resulting in contraversiveocular deviation.
3.3. An irritativelesion of the intralaminarthalamic neurons, which discharge
for contralateralsaccades, could theoretically cause contraversiveocular
deviation.
4.4. Damage to the contralateralinhibitory center could also be responsible.
Selected disorders of horizontal gaze

111. (4) Ping-Pong Gaze:
❑Ping-pong gaze is a slow conjugate horizontal
rhythmic oscillation that cycles every 4 to 8
seconds.
❑It occurs in comatose patients as a result of
bilateral cerebral or upper brainstem lesions or
metabolic dysfunction
Selected disorders of horizontal gaze

112. Gaze evoked phenomena