1. Nystagmus is defined as involuntary, rhythmic oscillations of the eyes and can be caused by disturbances in the visual, vestibular, or brainstem pathways.
2. There are three main types of nystagmus - physiological, sensory deprivation, and motor imbalance. Physiological nystagmus occurs normally while sensory deprivation nystagmus is due to reduced visual input and motor imbalance nystagmus arises from problems with eye movement control.
3. Specific forms of nystagmus include optokinetic nystagmus from moving visual stimuli, congenital pendular nystagmus associated with visual impairments like cataracts, and downbeat nystagmus linked to
2. Definition
• regular and rhythmic to-and-fro involuntary
oscillatory movements of the eyes - Khurana
• repetitive, rhythmic oscillations of one or both eyes
in any or all fields of gaze- V & A
Nystagmus
3. • due to disturbance or abnormality in any of the factors
responsible for regulate normal ocular posture and
movement:
Nystagmus
Etiology
Sensory visual pathway
Vestibular apparatus
Midbrain and cerebellum
4. • A nystagmus may be:
Nystagmus
Features
pendular or jerk nystagmus
rapid or slow
fine or coarse
Latent or manifest
pendular movements of equal velocity in each
direction; may be horizontal, vertical or rotatory
Jerk slow component in one direction and a fast
component in the other direction.
- Defined by the direction of the fast component;
may be right, left, up, down or rotatory.
6. a physiological jerk nystagmus
induced by presenting to gaze the
objects moving serially in one
direction, such as strips of a
spinning optokinetic drum
The eyes will follow a fixed strip
momentarily and then jerk back to
reposition centrally to fix up a new
strip.
Similar condition occurs while
looking at outside things from a
moving train.
OPTOKINETIC NYSTAGMUS
PHYSIOLOGICALNYSTAGMUS
7. fine jerk horizontal nystagmus
seen in normal persons on
extreme right or left gaze
ENDPOINT NYSTAGMUS
PHYSIOLOGICALNYSTAGMUS
8. a jerk nystagmus which can be elicited
by stimulating the tympanic membrane
with hot or cold water.
basis of caloric test
‘COWS’ (Cold–Opposite, Warm–Same)
If cold water is poured into right ear the
patient develops left jerk nystagmus (rapid
phase towards left), while the reverse
happens with warm water, i.e., patient
develops right jerk nystagmus
PHYSIOLOGICAL VESTIBULAR NYSTAGMUS
PHYSIOLOGICALNYSTAGMUS
10. A horizontal slow pendular nystagmus
usually associated with sensory deprivation
due to reduced central visual acuity
common causes:
congenital cataract
congenital toxoplasmosis
macular hypoplasia
Aniridia
Albinism
optic nerve hypoplasia
Leber’s congenital amaurosis
CONGENITAL PENDULAR (OCULAR) NYSTAGMUS
SENSORYDEPRIVATION(OCULAR)NYSTAGMUS
Aniridia
Albinism
11. • occurs in monocular adults when they
develop decreased visual acuity in the
only seeing eye
• pendular
ACQUIRED OCULAR NYSTAGMUS
SENSORYDEPRIVATION(OCULAR)NYSTAGMUS
Director Nick Fury
S.H.I.E.L.D.
12. • rapid rotatory type
• occurs in coal mine workers
• probably results from fixation difficulties
in the dim illumination
MINER’S NYSTAGMUS
SENSORYDEPRIVATION(OCULAR)NYSTAGMUS
14. • a hereditary nystagmus of unknown
etiology which persists throughout life
• bilateral, horizontal jerk nystagmus with
rapid phase towards the lateral side
• not present during sleep
CONGENITAL JERK NYSTAGMUS
MOTORIMBALANCENYSTAGMUS
15. • not present when both eyes are open
• appears when one eye is covered
• a jerk nystagmus with rapid phase
towards the uncovered eye
LATENT NYSTAGMUS
MOTORIMBALANCENYSTAGMUS
16. • special type of acquired nystagmus in
childhood
• In its complete form triad:
• TORTICOLLIS
• PENDULAR NYSTAGMUS
• HEAD NODDING
• fine pendular horizontal nystagmus
• Signs usually develop within the 1st yr or
2 of life
• self-resolves by the age of 3 years
SPASMUS NUTANS
MOTORIMBALANCENYSTAGMUS
17. • due to diseases of the 8th nerve or
vestibular end organ
• jerky, fine, rapid and horizontal-rotatory
PERIPHERAL VESTIBULAR NYSTAGMUS
MOTORIMBALANCENYSTAGMUS
18. • may be of the following types:
a. Upbeat nystagmus
the fast component is upward
lesions of central tegmentum of brain
stem
b. Down beat nystagmus
fast component is downward
posterior fossa diseases and compression
at the level of foramen magnum
cerebellar lesions and Arnold Chiari
syndrome.
c. Periodic alternative nystagmus
jerk nystagmus
shows fluctuations in amplitude and
direction
may occur due to vascular or
demyelinating brain stem-cerebellar
lesions
CENTRAL VESTIBULAR NYSTAGMUS
MOTORIMBALANCENYSTAGMUS
a.
b.
19. • a slow horizontal jerk nystagmus due to
upper brain stem dysfunction
• Eyes jerk back to maintain eccentric gaze
GAZE-PARETIC NYSTAGMUS
MOTORIMBALANCENYSTAGMUS
(Not the legit illustration…)
20. • jerk nystagmus with bilateral fast
component towards the medial
side
• associated with retraction of the
globe in convergence
CONVERGENCE RETRACTION NYSTAGMUS
MOTORIMBALANCENYSTAGMUS
21. • one eye rises up and intorts, while
the other shifts down and extorts
• upper brain stem lesions
SEE-SAW NYSTAGMUS
MOTORIMBALANCENYSTAGMUS
22. • Rare condition
• sudden esotropia develops in
infancy to dampen the horizontal
nystagmus
NYSTAGMUS BLOCKAGE SYNDROME
MOTORIMBALANCENYSTAGMUS
26. 1. Associated with lesions of central tegmentum of brain stem
2. posterior fossa diseases and compression at the level of foramen
magnum
3. Triad of torticollis, pendular nystagmus, and head nodding
4. Appears only when one eye is covered
5. Caused by aniridia, albinism, or congenital cataract
Short Term Memory Exercise
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KEY
1.UpbeatNystagmus
2.DownbeatNystagmus
3.SpasmusNutans
4.LatentNystagmus
5.CongenitalPendularNystagmus
Leber congenital amaurosis is an eye disorder that primarily affects the retina, which is the specialized tissue at the back of the eye that detects light and color. People with this disorder typically have severe visual impairment beginning in infancy.
Amaurosis- partial or total blindness without visible change in the eye, typically due to disease of the optic nerve, spinal cord, or brain.
Play video: 4:53
Torticollis- painfully twisted and tilted neck. The top of the head generally tilts to one side while the chin tilts to the other side
a
Not the legit illustration…
Not the legit illustration…
Esotropia is a form of strabismus in which one or both eyes turns inward.