Localization Neurology Eye Movement and Foot Drop

LOCALIZATION NEUROLOGY EPISODE IV EYE MOVEMENT AND FOOT DROP

1 EPISODE IV 2012 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-temporal- occipital 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 LEFT RIGHT

III III

VI MLF VI

PPRF PPRF RIGHT CORTEX LEFT CORTEX LEFT RIGHT

III III

VI MLF VI

PPRF PPRF RIGHT CORTEX LEFT CORTEX INFRANUCLEAR LESION ABNORMAL EYE MOVEMENT

• 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 Superior rectus (SR) oblique (SO)

Lateral Medial rectus (LR) rectus (MR)

Inferior Inferior rectus (IR) 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

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 III V1 V2 IV V2 VI V3 V3 Apex of Superior orbital fissure Carvernous sinus petrous bone III, IV, VI, V1 III, IV, VI, V1, V2 V, VI Jugular foramen (IX, X, XI) Foramen Front 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

Supranuclear Infranuclear

Long tract sign

INO Extraaxial Intraaxial 1 1/2 Exclude NMJ, muscle

Ungroup group

Foramen syndrome 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 Sup r. Gluteal Hip extensor G.Maximus L5, S1 Inf r. Gluteal FOOT DROP/sciatic nerve lesion

Common Peroneal Nerve - tibialis anterios (ankle dorsiflex) - EHL (big toe dorsiflex) Sciatic nerve - 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 Bilateral hyperreflexia Normal or Peripheral hyporeflexia polyneuropathy UMN lesion L4,5 radiculopathy Lumbosacral plexopathy Sciatic Neuropathy Peroneal neuropathy FOOT DROP with DECREASE REFLEX

Foot inversion (tibialis posterior) Weakness No weakness

Hip abduction Peroneal neuropathy (Gluteus medius) - Injury - Entrapment neuropathy No weakness Weak (Wt loss, bed ridden, cross leg, underlying PN) Sciatic L4,5 neuropathy LS plexus