gaze palsy

Gaze Palsy

Presenter- Dr Shubhangini J Moderator-Dr Monica Samant

Ocular Motor system-

Nuclear

Supranuclear

Infranuclear

Inter nuclear

Supranuclear control of ocular motility-

Versions-Same

direction

Vergence-Opposite direction

Supranuclear control

Eye Movements-

Eye Movement

s

Version

Saccades

Smooth Pursuit

Optokinetic

Vestibulo-ocular

Vergence

Divergence

Convergence

Saccadic System-

Cells in PPRF

Burst Cell-sends pulse step to move

the eye

Pause Cell-inhibits firing of burst cell

allowing burst cell to initiate

saccade

Tonic Cell –maintain the eye position

Smooth Pursuit System

Vestibulocerebellar system-Important input of gaze systemModulate eye movementsStabilize eye against the gravitatinal &

accelerational forceMaintaining clear vision

Cerebellum-Eye movementsFixation accuracySuppress the vestibulo-ocular reflexControls smoothness of pursuit movements Accuracy of saccades

Lesion of Supranuclear oculomotor pathways -Based on anatomical location-

Lesions of internuclear systemImmediate premotor structure in the brain

PPRF Posterior commisure Rostral mesencephalon

Cerebral hemisphereDescending pathway from cerebral hemisphereSuperior colliculusThalamus

Clinical ExaminationAsymptomatic for gaze palsyBlurring of visionDiplopia

Pre-requisite-Observe position of eye in primary gazeDuctions Versions & vergence Pursuit Saccades

Oculocephalic maneuvers-Dolls eye reflexTilt the head 30 degree forward & fixate a

distant targetRotate the head in direction opposite to gaze

palsy Direct projection from vestibular system to

ocular motor nuclei Prenuclear,nuclear infranuclear reflex does

not overcomeLesion in cerebral cortex overcome by VOR

Vestibular ocular reflex -Tilt the head by 60 degree & irrigate external

auditary meatus with cool/warm water In normal subject/supranuclear gaze palsy

eye deviate towards the irrigated side- nystagmus with fast phase to opposite side

Fast phase towards the stimulated eye when warm water is used

Supranuclear eye movement disorder-

Gaze palsy

Horizontal

Vertical

Vertical gaze palsy-Midbrain lesionB/L cerebral hemisphere

dysfunctionParkinsons diseaseProgressive supranuclear

palsylipidosis

Parinaud syndrome-Dorsal midbrain syndrome

Lesion of posterior commisure & MRFCause- compression by mass in pineal

regionDilatation of third ventricleMidbrain infarctionmultiple sclerosisAV malfomation

Poor to absent upgazeConvergence retraction nystagmus in

upgazeColliers signSetting sun sign

Parinaud syndrome-EMG shows co-contraction of occulomotor

innervated muscles- retraction of globeNeuroimaging scanSurgical treatment causes resolution of

ocular findings

Progressive supranuclear palsy-

Lesion of mesencephalic structure-Steele-Richardson-Olszewski syndromeOnset –after 40 yearsDisorder of basal gangliaMarked rigidity –trunk & neckLittle tremorDifficulty with vertical eye movements down

> upProgresses to horizontal gaze disorderEnd stage – global ophthalmoplegia

Progressive supranuclear palsy-

Vertical direction more severely affected initially  Voluntary saccades affected first, convergence,

and smooth pursuit later Slowing of saccade velocitySupranuclear movements primarily affected

(vestibulo-ocular reflex spared)Square wave jerksGait abnormalitiesNuchal rigidity

Progressive supranuclear palsy-

Eyelid abnormalities: upper eyelid retraction reduced blink rate apraxia of eyelid opening blepharospasm

Postural instability with falls (often backwards)Cervical and axial dystonia

Progressive supranuclear palsy-

Wilson’s diseaseHuntington diseasKernicterous

Parkinsons disease-Lesion of descending pathway from cerebral

hemisphereUpgaze palsy affecting saccades followed by

pursuitCogwheel pursuit

Lipidosis-Lipid storage disease variant of niemann

picks diseaseVertical saccadesIntact vertical oculocephalic maneuversProgressive dementia in late childhoodChoreoathetosishepatosplenomegaly

Whipples disease-Involvement of CNS – supranuclear gaze

palsyInitially verticalProgressive dementiaHypersomniaAtaxiaUveitis

Monoocular elevation paresis-No ocular deviation in primary gaze Inability to elevate one eyePrenuclear congenital unilateral midbrain

lesion Oculocephalic maneuver is normal Lesion in pretectum Connection of riMLF to the occulomotor

nucleiForced duction & tensilon test are negative

Monoocular elevation paresis-

Skew deviation-Skew deviation is a vertical divergence“prenuclear” lesion of the vertical vestibulo-

ocular pathways in the brainstem or cerebellum.

Comitant, associated with cyclotorsion of one or both eyes.

Noncomitant it can mimic a partial third or fourth cranial nerve palsy

Skew deviation-Occur most commonly with vascular lesions

of the pons or lateral medulla (Wallenberg's syndrome)

lesions of the midbrain or upper ponsAlternating skew deviation, the hypertropia

changes with the direction of gaze. The adducting eye usually is hypotropic,mimick superior oblique overaction.

Skew deviation-

Ocular tilt reaction-cyclotorsion of both eyes, and paradoxical

head tilt, all to the same side – that of the lower eye

A tonic (sustained) ocular tilt reaction occurs with lesions of the ipsilateral utricle, vestibular nerve or nuclei, or a lesion in the region of the contralateral interstitial nucleus of Cajal and medial thalamus

A phasic (paroxysmal) ocular tilt reaction occurs with lesions of the ipsilateral interstitial nucleus of Cajal and may respond to baclofen.

Horizontal gaze palsy-More commonVary from

Gaze evoked nystagmusDysmetria of movementsTotal inability to move the eyeCommonly occur in CVA patients

Internuclear ophthalmoplegia-Lesion in MLFBetween the abducens nucleus and C/L

medial rectus subnucleus of the oculomotor nerve

Impairs adducting saccades of the ipsilateral eye, which become either slow or absent

DysmetriaDisconjugate nystagmus.

Internuclear ophthalmoplegia-If INO is bilateral abduction saccades also may be slow Upward beating and torsional nystagmus Other clinical features

skew deviationdefective vertical smooth pursuitimpairment of the vertical VORimpaired ability to suppress or cancel the

vertical VOR.

Internuclear ophthalmoplegia-Occur with a variety of disorders of

brainstemVascularDemyelinatingMetastatic

Must be differentiated from the pseudo-INO of myasthenia or a long-standing exotropia.

One & half syndrome-Damage to the caudal pons Ipsilateral MLF and either the ipsilateral

PPRF or the abducens nucleusIt results in an ipsilateral gaze palsy with an

ipsilateral INOIntact horizontal movement is abduction of

the contralateral eye

One & half syndrome-If the facial nerve nucleus or fasciculus is

involved, oculopalatal myoclonus may develop Most common causes

multiple sclerosis and brainstem strokefollowed by metastatic primary brainstem tumors

Ocular myasthenia may cause a pseudo-one-and-a-half syndrome

Ocular motor apraxia-Loss of or severely diminished volitional

saccades Retention of the fast phases of vestibular

nystagmus • Difficult horizontal saccades• Head thrust towards desired

directionCongenit

al• Balint syndrome• Both Horizontal & Vertical• Simutagnosia/optic ataxiaAcquired

Convergence paralysis-Midbrain lesions ,dorsal midbrain syndrome. Cerebellar degeneration, Parkinson's

disease, and progressive supranuclear palsy, are associated with poor convergence.

Lack of pupillary constriction on attempted convergence may differentiate psychogenic convergence paralysis from organic disease.

Divergence paralysis-Uncrossed horizontal diplopia Intermittent or constant esotropia Abduction is full. Break in fusion later in life Treated easily with base-out prisms for the

distance correction Divergence paralysis is a controversial entity,

difficult to differentiate from divergence insufficiency and bilateral sixth cranial nerve palsies.

Functional gaze palsies-Horizontal gaze palsy – miosis during

attempted gazeSaccades-VOR should be stimulated

(oculocephalic maneuvers,calorics,chair rotation ), OKN test

Pursuit

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