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LOCALIZATION

NEUROLOGY

EPISODE IV EYE MOVEMENT AND FOOT DROP

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EPISODE IV2012

EYE MOVEMENTLOCALIZATION NEUROLOGY

PAWUT MEKAWICHAI MD

DEPARTMENT of MEDICINE

MAHARAT NAKORNRAJSIMA HOSPITAL

ABNORMAL

EYE MOVEMENT

SUPRANUCLEAR

INFRANUCLEAR

INTRINSIC

EXTRINSIC

SUPRANUCLEAR LESION

Centers: Cerebrum, Cerebellum, Brainstem

Three Control Networks

� Saccade System (finding)

Fast eye movement toward contralateral visual space

� Pursuit System (follow)

Slow eye movement toward ipsilateral visual space

� Vestibule-Ocular System (Doll’s eye)

Maintains image stability during head movement

– Enable the two eyes to conjugate

SUPRANUCLEAR CONTROL

Saccade System (finding)

purpose = to bring objects of interest onto the fovea

Pathways

Initiation :

contralateral frontal lobe

(Brodmann area 8)

frontal eye field gaze center

Decussates: lower midbrain

Ends: contralateral PPRF

SUPRANUCLEAR CONTROL-saccade

Pursuit System (follow)

purpose = to hold image of moving target on the fovea

Pathways:

Initiation :

ill-defined origin in parieto-temporal-

occipital junction

-probable double

End: ipsilateral PPRF

SUPRANUCLEAR CONTROL-pursuit

cold water: simulates a destructive vestibular lesion

jerk nystagmus with slow phase to

ipsilateral side, jerk to opposite side

warm water: simulates an irritative vestibular lesion

jerk nystagmus to the ipsilateral side

caloric testing = COWS (cold opposite / warm same)

Vestibulo-Ocular System (Doll’s eye/Caloric test)

purpose = to hold images of world steady on the retina with rapid, brief head

rotations

SUPRANUCLEAR CONTROL-VOS

Brainstem Gaze Centers

�Vertical Gaze Center:

Midbrain

� Horizontal Gaze Center:

Pons

Paramedian Pontine

Reticular Formation

(PPRF)

SUPRANUCLEAR CONTROL

MLF MLF

Cortical Input:

Paramedian Pontine Reticular Formation: PPRF

� The zone surrounding CN VI nucleus

� Combines the various eye movement commands

- Sends integrated signal to ocular motor nuclei

� Receives input from:

- Contralateral frontal cortex:

regulates saccades

- Ipsilateral parietooccipital cortex:

regulates pursuits

� Lesions

- Destructive

- Irritative

SUPRANUCLEAR CONTROL

ABNORMAL EYE MOVEMENT

Gaze Palsy: supranuclear lesion

� Decrease ability of conjugate gaze

� Caused by supranuclear lesions

in brainstem or cerebrum

� Bilateral

� Overcome by caloric stimulation

Ocular Palsy: infranuclear lesion: diplopia

� Intrinsic BS lesion: long tract sign

� Extrinsic BS lesion

• Nerve lesion

• NMJ (MG)

• Muscle disease – thyroid disease

SUPRANUCLEAR LESION

Hemispheric lesion

� Destructive: produce bilateral deviation toward side

of the lesion & away from hemiparesis side

� Irritative: motor seizures = gaze out side of lesion

Midbrain Lesions:

� Affect the center responsible for

voluntary upward gaze

� Produces upward gaze paralysis

� Parinaud’s Syndrome

Pontine Lesions: ipsilateral gaze

� Disorders of conjugate horizontal gaze

� Eye deviation toward side of hemiparesis

� Characteristically resistant to reflex maneuvers

� Associated with abducens nerve dysfunction

SUPRANUCLEAR LESION

Internuclear Ophthalmoplegia:

� Lesions of the medial longitudinal fasiculus (MLF)

� Conjugate gaze of CN III & CN IV is uncoupled

� Excursion of the adbucting eye is full & adduction of the

contralateral eye is impaired

� Cannot be overcome by caloric stimulation

� Distinguished from CN III palsy by the preservation of

adduction w/ convergence

� Cause: small vessel disease, demyelination

SUPRANUCLEAR LESION

One and a Half Syndrome:

� Lesions of the medial longitudinal fasciculus

( MLF) and paraabducen nucleus

� Conjugate gaze of CN III & CN IV is uncoupled

� Affected eye cannot move horizontally

� Unaffected eye cannot abduct

� Cannot be overcome by caloric stimulation

� Distinguished from CN III palsy by the preservation of

adduction w/ convergence

� Cause: small vessel disease, demyelination

SUPRANUCLEAR LESION

nystagmus

INO

1 1/2

INO

One and a half

nystagmus

SUPRANUCLEAR LESION

MLF

PPRF

VIVI

III III

PPRF

LEFT RIGHT

RIGHT CORTEX LEFT CORTEX

MLF

PPRF

VIVI

III III

PPRF

LEFT RIGHT

RIGHT CORTEX LEFT CORTEX

INFRANUCLEAR LESION

Gaze Palsy: supranuclear lesion

� Decrease ability of conjugate gaze

� Caused by supranuclear lesions in brainstem or cerebrum

� Bilateral

� Overcome by caloric stimulation

Ocular Palsy: infranuclear lesion: diplopia

� Intrinsic BS lesion: long tract sign

� Extrinsic BS lesion

• Nerve lesion

• NMJ (MG)

• Muscle disease – thyroid disease

ABNORMAL EYE MOVEMENT

FORAMEN SYNDROME

SUBARACHNOIDAL SPACE

NERVE LESION

Cranial Nerves:

� CN III, IV, & VI

� SO4 LR6

EXTRAOCCULAR MUSCLE

CN III : MR, IR, SR, IO

CN IV : SO

CN VI : LR

Medial

rectus (MR)

Inferior

rectus (IR)Inferior

oblique (IO)

Lateral

rectus (LR)

Superior

oblique (SO)Superior

rectus (SR)

EXTRAOCCULAR MUSCLE

CN III : OCCULOMOTOR NERVE

FUNCTION

1. Parasympathetics : pupil constriction

2. Motor : eye movement : MR, IR, SR, IO

CLINICLAL

Pupil: fixed and dilated

Resting: laterally

Movement: lateral direction only

CN III : OCCULOMOTOR NERVE

CN III Nucleus:

� Superior Rectus receives fibers from

contralateral oculomotor nucleus

� Levator Palpebra receives bilateral innervation

CN III : OCCULOMOTOR NERVE

CN III Nerve Lesion vs Nuclear Lesion

� Nerve Lesion

– Unilateral Ophthalmoplegia

– Ipsilateral Ptosis

– Ipsilateral Pupillary Paralysis

� Nuclear Lesion

– Bilateral Ophthalmoplegia

– Bilateral Ptosis

– Ipsilateral Pupillary Paralysis

� General: diplopia, deviation down & out

CN III : OCCULOMOTOR NERVE

-CN III + superior cerebellar peduncle =

Nothnagel’s syndrome

- CN III + red nucleus = Benedikt’s syndrome

- CN III + cerebral peduncle = Weber’s syndrome

-CN III + superior cerebellar peduncle + red

nucleus =

Claude syndrome

Fascicular syndromes of the CN III nerve

CN III : OCCULOMOTOR NERVE

80% of diabetic CN III palsies are pupil sparing

95% of compressive CN III palsies have pupil involvement

Nuclear CN III palsies

- very rare

Uncal herneation syndrome of CN III nerve

- CN III passes along free edge of tentorium cerebelli

Posterior communicating artery aneurysm

- most common cause of painful, non-traumatic

ISOLATED CN III PALSY

CN III: OCCULOMOTOR NERVE

CN III:

� Nerve Lesions:

– Pituitary adenoma

– 1o or Metastatic Tumors, lymphoma

– Inflammation/infection

- Posterior Communicating artery aneurysm

- Ischemia (DM)

� Nuclear Lesions:

– Ischemia

– Central Demyelinating Disorders (MS)

CN III: OCCULOMOTOR NERVE

nerve carrying motor fiber to superior

oblique muscle

CN IV : TROCHEAR NERVE

nerve carrying motor fiber to superior oblique muscle

CN IV : TROCHEAR NERVE

unable to distinguish between nerve or nuclear lesions

� Ophthalmologic

� Excyclodeviation of the eye

� Vertical Diplopia

- Widest separation occurs w/ gaze away from

lesion

CN IV : TROCHEAR NERVE

CN IV : TROCHEAR NERVE

Superior oblique : downward and intorsion

Vertical diplopia : downward and contralateral side

Most common cause : fracture, injury

move

Head tilt to contralateral side

CN IV:

� Nerve Lesions:

– Head Trauma

– Ischemia

– Inflammation

– Pituitary Adenoma

� Nuclear Lesions:

– Ischemia

– Central Demyelinating Disorders

– Inflammation

CN IV : TROCHEAR NERVE

CN VI : ABDUCEN NERVE

Lying on petrous part of temporal bone with CN V

Out of skull by carvernous sinus

CN VI : ABDUCEN NERVE

Nucleus: lower part of pons

Closed relation with fiber of CN VII

Pass medial lemniscus and pyramidral tract

VI nerve + VII nerve + cerebral peduncle

medial pontine syndrome (Millard-Gubler syndrome)

VI nerve + cerebral peduncle

Raymonds syndrome

VI n. + V n. + VII n. + VIII n. + sympathetics

lateral pontine syndrome (Fovilles syndrome)

FASICULAR LESION

CN VI : ABDUCEN NERVE

SUBARACHNOID SPACE

� Elevated ICP CN VI palsy: false localizing sign

� Petrous apex syndrome of the VI nerve

passes under the petrosphenoidal ligament

petrous apex pathology may result in

VI+ VIII + VII + facial pain (V) = Gradenigo’s syndrome

true Gradenigo’s syndrome = otidis media complicated by petritis /

abscess

pseudo-Gradenigo’s syndrome = NPCA, CPA mass

CN VI : ABDUCEN NERVE

Nerve Lesions:

– Meningeal tumors

– Pituitary Adenoma

– Inflammation

- Increase intracranial pressure

Nuclear Lesions:

– Ischemia (pontine infarction)

– Central Demyelinating Disorders

– Inflammation

CN VI : ABDUCEN NERVE

� Cavernous sinus = III, IV, V1,V2,VI

� Superior orbital fissure = III, IV, V1, VI

� Orbital apex = II, III, IV, VI, V1

� Cerebellopontine angle = V, VII, VIII, (IX)

(acoustic neuroma, meningioma)

� Jugular foramen = IX, X, XI

(tumor, aneurysm)

FORAMEN SYNDROME

V1

V2

V3

III

IV

VI

CARVERNOUS SINUS

CN III

CN IV

V1

V2

V3

Superior orbital fissure

III, IV, VI, V1Carvernous sinus

III, IV, VI, V1, V2

Apex of

petrous bone

V, VI

Jugular foramen (IX, X, XI)Foramen

rotundum

(V2)

Foramen ovale

(V3)

Foramen spinosum

(middle meningeal a.)

Hypoglossal canal (XII)

Front

back

� Infection

Carvernous sinus thrombosis

Chronic granulomatous infection: TB, Fungal

� Vascular

CC fistular

Dural AVM

Aneurysm of intracarvernous part of carotid a. eg. posterior communicating a. aneurysm – CN III

FORAMEN SYNDROME

� Mass

Direct extension from skull base: CA nasopharynx

Metastasis: breast, lung

Granulomatous: Wegener’s granulomatosis

Hematologic: lymphoma, leukemia

Extension from sella tumor

� Idiopathic inflammatory (Tolosa-Hunt)

� Pseudotumor Occuli

FORAMEN SYNDROME

SUBARACHNOIDAL SPACE

� Meningeal inflammationMeningitis: TB, Bacterial, Fungus

Metastasis: Carcinomatous meningitis

Hematologic: lymphoma, leukemia

GBS (Miller-Fisher variant)

� Idiopathic pachy meningitis

� Menigioma en plaque

� Cranial neuritis – post viral, ischemic

� Diplopia is dysconjugated eye movement

� Supranuclear or infranuclear lesion

� Supranuclear lesion = lesion at gaze center

(midbrain or pons): INO, 1 ½

- sudden onset

� Infranuclear lesion = lesion at brain stem, cranial nerve

NMJ, muscle

DIPLOPIA

DIPOLPIA

Supranuclear Infranuclear

INO

1 1/2

Long tract sign

IntraaxialExtraaxial

Exclude NMJ, muscle

groupUngroup

Foramen syndrome Subarachnoidal space

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EPISODE IV 2012

FOOT DROPLOCALIZATION NEUROLOGY

PAWUT MEKAWICHAI MD

DEPARTMENT of MEDICINE

MAHARAT NAKORNRAJSIMA HOSPITAL

FOOT DROP

FOOT DROP

UMN lesion

� Spinal cord

� Motor cortex

LMN lesion

� Nerve root: L5

� Lumbosacral plexus

� Sciatic n.

� Peroneal n. (common, deep)

� Peripheral neuropathy: CMT

FOOT DROP

Action Muscle Root Nerve

Hip flexor Iliopsoas L 1,2 Femoral

Knee extensor Quadriceps L 2,3 Femoral

Ankle inversion Tibialis posterior L 4,5 Tibial

Ankle dorsiflex Tibialis anterior L 4,5 Peroneal

Toe extensor EHL L5, S1 Peroneal

Ankle eversion Peroneus L5, S1 Peroneal

Ankle plantarflex Gastrosoleus S 1,2 Tibial

Knee flexor Hamstrings S 1,2 Sciatic

FOOT DROP/root lesion

Action Muscle Root Nerve

Hip flexor Iliopsoas L 1,2 Femoral

Hip adductor Adductors L 2,3 Obturator

Hip abductor G. Medius L 4,5 Supr. Gluteal

Hip extensor G.Maximus L5, S1 Inf r. Gluteal

FOOT DROP/root lesion

FOOT DROP/sciatic nerve lesion

Sciatic nerve

Common Peroneal Nerve

- tibialis anterios (ankle dorsiflex)

- EHL (big toe dorsiflex)

- peroneous (foot eversion)

Tibial Nerve

- gastrosoleus (ankle plantar flex)

- tibialis posterior (foot inversion)

COMMOM PERONEAL

� Peroneus longus

� Peroneus brevis

DEEP PERONEAL

� Tibialis anterior

� EDL/B

� EHL

FOOT DROP/peroneal nerve lesion

Commom peroneal

Deep peroneal

FOOT DROP/peroneal nerve lesion

BilateralUnilateral

hyperreflexia Normal or

hyporeflexia

UMN lesion L4,5 radiculopathy

Lumbosacral plexopathy

Sciatic Neuropathy

Peroneal neuropathy

Peripheral

polyneuropathy

FOOT DROP

Foot inversion

(tibialis posterior)No weakness

Peroneal neuropathy

- Injury

- Entrapment neuropathy

(Wt loss, bed ridden,

cross leg, underlying PN)

Weakness

Hip abduction

(Gluteus medius)

No weaknessWeak

Sciatic

neuropathy

L4,5

LS plexus

FOOT DROP with DECREASE REFLEX