LOCALIZATION
NEUROLOGY
EPISODE IV
EYE MOVEMENT AND FOOT DROP
1
EPISODE IV2012
EYE MOVEMENT
LOCALIZATION NEUROLOGY
PAWUT MEKAWICHAI MD
DEPARTMENT of MEDICINE
MAHARAT NAKORNRAJSIMA HOSPITAL
2
ABNORMAL
EYE MOVEMENT
SUPRANUCLEAR
INFRANUCLEAR
INTRINSIC
EXTRINSIC
SUPRANUCLEAR LESION
SUPRANUCLEAR CONTROL
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
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-pursuit
Pursuit System (follow)
purpose = to hold image of moving target on the fovea
Pathways:
Initiation :
ill-defined origin in parieto-temporaloccipital junction
-probable double
End: ipsilateral PPRF
SUPRANUCLEAR CONTROL-VOS
Vestibulo-Ocular System (Doll’s eye/Caloric test)
purpose = to hold images of world steady on the retina with rapid, brief head
rotations
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)
SUPRANUCLEAR CONTROL
Brainstem Gaze Centers
Vertical Gaze Center:
Midbrain
Horizontal Gaze Center:
Pons
Paramedian Pontine
Reticular Formation
(PPRF)
MLF
MLF
SUPRANUCLEAR CONTROL
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
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
SUPRANUCLEAR LESION
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
INO
nystagmus
1 1/2
SUPRANUCLEAR LESION
nystagmus
INO
One and a half
RIGHT
LEFT
III
VI
III
VI
MLF
PPRF
RIGHT CORTEX
PPRF
LEFT CORTEX
RIGHT
LEFT
III
VI
III
VI
MLF
PPRF
RIGHT CORTEX
PPRF
LEFT CORTEX
INFRANUCLEAR LESION
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
NERVE LESION
FORAMEN SYNDROME
SUBARACHNOIDAL SPACE
EXTRAOCCULAR MUSCLE
Cranial Nerves:
CN III, IV, & VI
SO4 LR6
EXTRAOCCULAR MUSCLE
Superior
oblique (SO)
Superior
rectus (SR)
Medial
rectus (MR)
Lateral
rectus (LR)
Inferior
rectus (IR)
Inferior
oblique (IO)
CN III : MR, IR, SR, IO
CN IV : SO
CN VI : LR
CN III : OCCULOMOTOR NERVE
FUNCTION
1. Parasympathetics : pupil constriction
2. Motor : eye movement : MR, IR, SR, IO
CN III : OCCULOMOTOR NERVE
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
Fascicular syndromes of the CN III 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
CN III: OCCULOMOTOR NERVE
ISOLATED CN III PALSY
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
80% of diabetic CN III palsies are pupil sparing
95% of compressive CN III palsies have pupil involvement
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 IV : TROCHEAR 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
Superior oblique : downward and intorsion
Vertical diplopia : downward and contralateral side
Most common cause : fracture, injury
move
Head tilt to contralateral side
CN IV : TROCHEAR NERVE
CN IV:
Nerve Lesions:
– Head Trauma
– Ischemia
– Inflammation
– Pituitary Adenoma
Nuclear Lesions:
– Ischemia
– Central Demyelinating Disorders
– Inflammation
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
CN VI : ABDUCEN NERVE
FASICULAR LESION
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)
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
FORAMEN SYNDROME
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)
CARVERNOUS SINUS
CN III
CN IV
V1
V2
V3
III
IV
VI
V1
V2
V3
Superior orbital fissure
III, IV, VI, V1
Carvernous sinus
III, IV, VI, V1, V2
Apex of
petrous bone
V, VI
Jugular foramen (IX, X, XI)
Front
Foramen
rotundum
(V2)
Foramen ovale
(V3)
Foramen spinosum
(middle meningeal a.)
Hypoglossal canal (XII)
back
FORAMEN SYNDROME
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
SUBARACHNOIDAL SPACE
Meningeal inflammation
Meningitis: 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
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
DIPOLPIA
Infranuclear
Supranuclear
Long tract sign
Extraaxial
INO
1 1/2
Intraaxial
Exclude NMJ, muscle
group
Foramen syndrome
Ungroup
Subarachnoidal space
EPISODE IV 2012
FOOT DROP
LOCALIZATION NEUROLOGY
PAWUT MEKAWICHAI MD
DEPARTMENT of MEDICINE
MAHARAT NAKORNRAJSIMA HOSPITAL
52
FOOT DROP
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/root lesion
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/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)
FOOT DROP/peroneal nerve lesion
COMMOM PERONEAL
Peroneus longus
Peroneus brevis
DEEP PERONEAL
Tibialis anterior
EDL/B
EHL
FOOT DROP/peroneal nerve lesion
Commom peroneal
Deep peroneal
FOOT DROP
Unilateral
hyperreflexia
UMN lesion
Bilateral
Normal or
hyporeflexia
Peripheral
polyneuropathy
L4,5 radiculopathy
Lumbosacral plexopathy
Sciatic Neuropathy
Peroneal neuropathy
FOOT DROP with DECREASE REFLEX
Foot inversion
(tibialis posterior)
Weakness
No weakness
Hip abduction
(Gluteus medius)
Peroneal neuropathy
- Injury
- Entrapment neuropathy No weakness
Weak
(Wt loss, bed ridden,
cross leg, underlying PN) Sciatic
L4,5
neuropathy LS plexus