8/13/2019 4th&6thnerve Palsy

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4th NERVE PALSY

ANATOMY CAUSES Entirely MOTORin function.

Located at anterior part of gray

matter surrounding the cerebralaqueduct of the midbrain

Inferior to ocular motor nucleus atlevel of inferior colliculus

Leave the posterior surface ofbrainstem, emerges from midbrain& decussates with the nerve of theopposite site.

Responsible for turning the eyedownward & laterally

Midbrain ecussates

contralaterally carvenous sinus

!uperior orbital fissure !uperioroblique m

1. CONGENITAL

ysgenesis of "thnerve nucleus,

abnormality of peripheral nerve

2. ACCQUIRED

#ead trauma $severe w L%'

Microvasculopathy secondary to

diabetes, atherosclerosis, orhypertensionalso may causeisolated fourth nerve palsy

(umor

)neurysm

PRESENTATION TREATMENT *ertical, torsional, or oblique

diplopia. worse on downga+e andga+e away

In trauma symptoms immediately

after regaining consciousness.

#ead tilt, away from affected side to

reduce their diplopia $parado-ichead tilt torticollis'

evelop facial asymmetry with

longstanding head tilt

/risms small deviations anddiplopia without torsional.

0otulinum to-in

Eye muscle surgery

6thNERVE PALSY

http://emedicine.medscape.com/article/241381-overviewhttp://emedicine.medscape.com/article/241381-overview

8/13/2019 4th&6thnerve Palsy

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ANATOMY CAUSES !mall motor nerve supplies the

lateral rect! "!cle.

Its nucleus situated beneath the

floor of the upper part of "thventricle, close to midline &beneath colliculus facialis.

/ass anteriorly through pons &

emerge in the groove betweenlower border of pons & medulla.

Entirely MOTOR

Responsible for turning the eyelaterally.

Midbrain arvenous sinus $lying

below & lateral to internal carotid

artery' !uperior orbital fissure Lateral rectus

Elevated intracranial pressure canresult in downward displacement ofthe brainstem

!ubarachnoid space lesions

/ostviral syndrome in youngerpatients

)n ischemic mononeuropathy in the

adult population.

PRESENTATION TREATMENT Esotropia

#eadturn 0inocular diplopia $worse at distance'

*ision loss

/ain

#earing loss

!ymptoms of vasculitis, particularly

giant cell arteritis

(rauma

/apilledema $if increased intracranial

pressure'

1ystagmus $usually in children, ie,secondary to pontine glioma'

%titis media

(ender, enlarged, nonpulsatile

temporal arteries in giant cellarteritis

)n alternating patching 2 children

/atched or have their lenses3fogged3 with clear tape or nailpolish to reduce their diplopia 2adult

!urgery