This document discusses ocular movements and their neural control pathways. It describes four types of ocular movements - versions, ductions, vergences, and supranuclear eye movements. Supranuclear eye movements include saccades, smooth pursuit, vestibulo-ocular, and optokinetic movements. The document outlines the cortical and brainstem control centers that generate each type of eye movement, including pathways like the medial longitudinal fasciculus. It also discusses various disorders that can occur with abnormalities in horizontal and vertical gaze, vergence, and other types of supranuclear eye movements.

1. BY
DR.ANUPAMA MANOHARAN
D.O OPHTHALMOLOGY
1ST YEAR PG STANLEY MEDICAL
COLLEGE AND HOSPITAL

2. OCULAR MOVEMENTS
FOUR TYPES OF OCULAR MOVEMENTS
DUCTIONS
(monocular)
VERSIONS
(binocular)
VERGENCES
(binocular)
SUPRA-NUCLEAR
EYE
MOVEMENTS

3. SUPRANUCLEAR EYE MOVEMENTS
Basic supranuclear control systems of ocular
movements,which must function simultaneously
I.SACCADES
II.PURSUITS
III.VESTIBULO-OCULAR MOVEMENTS
IV.OPTOKINETIC MOVEMENTS

4. SUPRA-NUCLEAR EYE MOVEMENTS
1.SACCADES-Rapid eye movements,which are generally voluntary
re-fixation movements(to move the eyes quickly from one object to
another)
TYPES
HORIZONTAL SACCADES VERTICAL SACCADES

5. SUPRA-NUCLEAR EYE MOVEMENTS
2.PURSUITS-Smooth following movements which
maintain visual axes on any slow moving object.
3.VESTIBULO-OCULAR MOVEMENTS-Co-ordinated
eye movements with respect to gravity and head
positions.
4.OPTOKINETIC MOVEMENTS-Co-ordinated eye
movements when the environment moves.

6. EYE MOVEMENTS-FUNCTIONAL CLASSIFICATION
GAZE SHIFT GAZE MAINTENENCE
1.SACCADES- To bring images of
objects of interest onto the fovea
1.VESTIBULAR- To hold images
on the retina during brief
head rotation
2.SMOOTH PURSUIT- To keep
the image of a moving target on
the fovea
2.OPTOKINETIC- To hold images
on the retina during sustained
head rotation
3.VERGENCE- To move the eyes
in opposite direction
3.FIXATION- To hold eyes
conjugately in a particular position

7. HIERARCHY OF OCULAR MOTOR CONTROL

8. SUPRANUCLEAR PATHWAY
CORTICAL
CONTROL
CENTRES
SUBCORTICAL
CONTROL
CENTRES
FRONTAL
OCULAR MOTOR
AREA
(saccadic eye
movement
system)
PARIETO-
OCCIPITOTEMPO
RAL(POT)
JUNCTION
(smooth pursuit
eye movements)
BRAINSTEM CONTROL
CENTRES:
1.PARAMEDIAN PONTINE
RETICULAR FORMATION(PPRF)
2.ROSTRAL INTERSTITIAL
NUCLEUS OF MEDIAL
LONGITUDINAL
FASCICULUS(riMLF)
3.POSTERIOR COMMISSURE
4.SUPERIOR COLLICULUS
5.MEDIAL LONGITUDINAL
FASCICULUS
6.CONVERGENCE AND
DIVERGENCE CENTRE
7.VESTIBULAR APPARATUS
8.CEREBELLUM

9. SUPRANUCLEAR CONNECTIONS OF
OCULAR MOTOR PATHWAY

11. CEREBRAL CORTEX
1.FRONTAL OCULAR MOTOR AREA:
Involved in the saccadic eye movement system.
Four main cortical areas involved in generation
of saccades:
i)Frontal eye field(FEF)-Brodman’s area 8
ii)Supplementary eye field(SEF)
iii)Dorsolateral prefrontal cortex (DLPFC)
iv)Posterior eye field(PEF)

12. CEREBRAL CORTEX
2.PARIETO-OCCIPITOTEMPORAL(POT) JUNCTION:
Control of smooth pursuit eye movements and object
tracking in space.
Confluence of Brodmann areas 19,37,39.
Cortical areas involved in pursuit movements:
Middle temporal(MT) visual area
Medial superior temporal(MST) visual area

13. BRAINSTEM CONTROL CENTRES

14. CONNECTIONS OF MEDIAL LONGITUDINAL
FASCICULUS(MLF)

15. BRAINSTEM CONTROL CENTRES
6.CONVERGENCE CENTRE:
 Convergence centre : Pretectal area (mesencephalic reticular formation, just
dorsal to the third nerve nuclei )
 Inputs from bilateral cerebral hemispheres give inputs to the centre and from
there to both 3rd nerve nuclei.

16. BRAINSTEM CONTROL CENTRES
7.VESTIBULAR APPARATUS:
Receptor specialized to sense changes of equilibrium and position.
Entirely reflexive(involuntary) and confined to the brainstem.
The membranous labyrinth cushioned by perilymph contains:
1.Three semicircular canals & their respective cristae
sense head rotation and measure angular acceleration
2.Otolith organs(saccule and utricle) & their respective maculae
sense head position and measure linear acceleration

17. SCC PROJECTIONS - EXCITATORY

18. DYNAMIC EYE RESPONSE
 This system repositions the eyes during acceleration and
deceleration of the head.
 The endolymph within the semicircular canals is
displaced when the head is moved. This results in a
change in pressure on the ciliated cells of the crista
ampullaris, resulting in a stimulus to the brain.
 Once the head movement reaches a stable unchanging
velocity, the pressure gradient disappears, and the
peripheral vestibular signal disappears 30 to 45 seconds
later.
 Thus, the semicircular canals make no contribution to
the maintenance of static ocular position.

19. BRAINSTEM CONTROL CENTRES
8.CEREBELLUM:
2 parts contribute to ocular motor control
1.VESTIBULOCEREBELLUM
Stabilization of sight during
motion
2.DORSAL VERMIS OF
POST.LOBE AND FASTIGIAL
NUCLEI
Voluntary gaze shifting
(saccades,pursuit,vergence)

20. SUPRA-NUCLEAR EYE MOVEMENT SYSTEMS
1.SACCADIC SYSTEM:
 Rapid conjugate eye movements performed to bring
image of an object quickly on the fovea.
CHARACTERISTIC FEATURES OF SACCADES:
1.Place the image on the fovea
2.Alertness required.
3.Saccadic omission
4.Ballistic movements- Once initiated,they cannot be
stopped or modified during the course of movement
5.Long delay of 200msec from stimulus to execution.
6.Velocity-100degrees/sec to 700degrees/sec

21. SACCADIC SYSTEM

22. SACCADE CONTROL

23. CONTROL OF HORIZONTAL SACCADES- BRAINSTEM PATHWAY

24. CONTROL OF VERTICAL SACCADES-BRAINSTEM PATHWAY

25. SUPRANUCLEAR EYE MOVEMENT SYSTEMS
2.SMOOTH PURSUIT SYSTEM
Tracking movements of the eye as they follow moving objects.
Ipsilateral cortical control
CHARACTERISTIC FEATURES OF PURSUITS:
1.Images moving away from the fovea - strongest stimuli for pursuit
movements
2. Latency- 125msec
3.Can keep up with targets moving up to 30 to 40 degrees/sec.
Beyond that point, saccades have to be made to catch up.
4.Limited ability to follow targets moving back and forth;beyond 2Hz, it
breaks down.
5.Only one image can be tracked normally.
6.Can track even an after image placed on the retina of some real
object in space or bright light
7.Effectiveness - dependent on the degree of alertness

26. SMOOTH PURSUIT SYSTEM

27. SMOOTH PURSUIT CONTROL

28. SUPRANUCLEAR EYE MOVEMENT SYSTEMS
3.VERGENCE MOVEMENT SYSTEMS
Drive the eyes in opposite directions to maintain the image of an
object on the fovea of both eyes as the object moves towards or
away from the observer.
Disparity between the location of images on the retina of each eye
FUSIONAL VERGENCE
Loss of focus of images on the retina(retinal blur)
ACCOMODATIVE VERGENCE
CHARACTERISTICS:
1.Very slow(20 degrees/sec)
2.Latency -160 msec

29. SUPRANUCLEAR EYE MOVEMENT SYSTEMS
Vergence eye movements generated bihemispherically
PREFRONTAL
REGION
PARIETO-OCCIPITAL
REGION
1.IMAGE BLUR/LOSS OF
IMAGE SHARPNESS
2.IMAGE DISPARITY
MIDBRAIN
RETICULAR
FORMATION

30. SUPRANUCLEAR EYE MOVEMENT SYSTEMS
4.VESTIBULAR OCULAR REFLEX:
 Brief, high frequency rotation of the head
 The maintainence of eye position without conscious input following a
change of head or body position.
 Centre: Vestibular nuclei
 Efferent: fibres carried via MLF to cranial nerve nuclei.

31. VESTIBULO-OCULAR MOVEMENTS-BRAINSTEM PATHWAY

32. SUPRANUCLEAR EYE MOVEMENT SYSTEMS
5.OPTOKINETIC REFLEX:
Combination of saccades and
smooth pursuit that allow tracking of
targets in turn.
Smoothly pursue one target, then
saccade in the opposite direction to
pick up the next target
Parieto-temporal junction (smooth
pursuit area) projects down to
ipsilateral vestibular nucleus, inhibits
it allowing ipsilateral smooth pursuit
Then, the FEF of the same
hemisphere generates a saccade
back (contralateral) to the next target

33. 1.HORIZONTAL GAZE ABNORMALITIES
A.SUPRANUCLEAR
1.Acute cerbrovascular accident(CVA)affecting frontal or parietal lobes.
2.Congenital ocular motor apraxia
3.Balint syndrome:acquired ocular motor apraxia
4.Spasticity of conjugate gaze(Cogan’s sign)
B.PONTINE CONJUGATE GAZE PALSY
Unilateral VI nerve nucleus or PPRF lesion
C.PARALYTIC PONTINE EXOTROPIA
A transient phenomenon seen in one and a half syndrome during the
first few days after onset.

34. HORIZONTAL GAZE ABNORMALITIES
D.INTERNUCLEAR OPHTHALMOPLEGIA
Lesion in MLF.
UNILATERAL INO:
 Straight eyes in the primary position
 Defective adduction of the eye on the side of the lesion
and nystagmus of the contralateral eye on abduction.
 Gaze to the side of the lesion is normal.
 Convergence is intact.
BILATERAL INO:
 Limitation of left adduction and ataxic nystagmus of the
right eye on right gaze.
 Limitation of right adduction and ataxic nystagmus of left
eye on left gaze.
 Convergence may be intact or impaired.
 WEBINO(wall eyed bilateral INO)-Rostral midbrain lesion
with convergence deficit with bilateral exotropia and
abducting nystagmus.

35. HORIZONTAL GAZE ABNORMALITIES
E.ONE AND A HALF SYNDROME:
PPRF AND MLF lesion
combined on the same side
 Ipsilateral gaze palsy
 INO
 Only residual movement-abduction of
contralateral eye-abduction
nystagmus

36. 2.VERTICAL GAZE ABNORMALITIES
A.DORSAL MIDBRAIN SYNDROME-PARINAUD
SYNDROME
(Pretectal syndrome, Sylvian aqueduct syndrome)
Straight eyes in primary position
Supranuclear upgaze palsy
Defective convergence
Large pupils with light-near dissociation
Lid retraction(collier sign)
Convergence-retraction nystagmus

37. VERTICAL GAZE ABNORMALITIES
B. PROGRESSIVE SUPRANUCLEAR
PALSY
(Steele-Richardson-Olszewski
syndrome)
Supranuclear gaze palsy-primarily of downgaze
and subsequently upgaze
Horizontal movements subsequently
impaired,with eventual globe palsy
Paralysis of convergence
Pseudobulbar palsy
Extrapyramidal rigidity, gait ataxia and dementia

38. VERTICAL GAZE ABNORMALITIES
C.MONOCULAR ELEVATION PARESIS:
No abnormality in primary position or looking down.
Diplopia in upgaze.
D.OCULOGYRIC CRISIS:
Tonic vertical/horizontal supranuclear deviation
of eyes.
Seen in post-encephalitic parkinsonism and
neuroleptic toxicity
E.DOWNGAZE PALSY:
Due to midbrain disease(stroke,tremor) with lesions
involving riMLF.
F. UPGAZE PALSY:
Associated with lesions located more dorsally.

39. 3.DISORDERS OF VERGENCE
A.Spasm of near reflex-Triad of convergence,miosis,
accomodation
B.Convergence paresis/paralysis-Diplopia at near or
easy fatiguability while reading
orthophoria at near
C.Divergence paresis/paralysis comitant esotropia at distance
full extraocular movements

40. 4.SKEW DEVIATION:
 Supranuclear motility disorder
 Eyes deviated vertically and exhibit
cyclotorsional disturbance.
 Most frequent cause-brainstem or
cerebellar stroke.
5.OCULAR TILT REACTION:
Lesion affecting peripheral(utricular) or
central otolithic pathways(vestibular nuclei,
MLF,INC)

41. THANK YOU