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Ocular Motility II
Kenn Freedman M.D.
Supranuclear
Cranial Nerves
Extra-ocular Muscles
Older woman with diabetes suffered sudden onset of Right IIIrd nerve palsy, left elevation
defect and left sided weakness
Oculomotor Nerve
• Complex Nucleus in Midbrain• Exits interpeduncular space passing several
vessels including PCA• Cavernous sinus• Superior Orbital Fissure• Superior and Inferior Divisions• Superior: Levator and SR• Inferior: MR, IR, IO
Left IIIrd Nerve palsy
Third Nerve Palsy
• Aneurysm• Microvascular – DM, HTN, heart disease
• Trauma
• Neoplasm
• Syphilis
• Other, Undetermined
Third Nerve Palsy
Third nerve palsy
Microvascular
Young woman presented with left sided headache and
drooping of her eyelid
Patient could not move her eye up, down or toward her nose, but she could abduct. Her pupil on the left was much larger than the
right.
PCA Aneurysm
Bilateral Ptosis with poor movement except abduction
Nuclear IIIrd nerve palsy
Brainstem Syndromes
• Weber’s - ipsalateral pupil involved IIIrd - contalateral hemiplegia - fasicle of IIIrd Nerve where traverses cerebral peduncle • Benedikt’s – ipsalateral pupil involved IIIrd - contralateral limb intention tremor, hypokinesia and ataxia - Fasicle of IIIrd nerve as it traverses the red nucleus
Management of Third Nerve Palsy
• When to do neuro-imaging and/or arteriogram?
• Important factors:
PAIN,
PUPIL,
PROGRESSION
Other Possible testing: CBC, ESR, BS
In general
You get imaging on
PUPIL INVOLVED
Third nerve palsies
Relative Pupil Sparing0.5mm <Anisocoria < 2mm
(Larger pupil still RTL)
• Out of 24 patients:
• 10 - had compressive lesions!
• 10 - “infarction”
• 4 - other
Neurology 2001; 56: 797
Imaging Options
• MRI
• MRA – no contrast
• Cerebral Arteriogram – some risk
Management Isolated Third Nerve Palsy
If patient is diabetic/ hypertensive and the pupil is not involved and they do not have too much pain*, then it would be reasonable to follow them up without imaging studies, depending on your comfort level. You should see some resolution of a microvascular palsy in at least two months.
Aberrant Regeneration
• One of many possible findings due to misdirection of axon fibers as healing occurs
1. Lid retraction on downgaze2. Lid elevation or pupil constriction with
attempted adduction3. Globe retraction with attempted upgaze or
downgaze4. Others also possible
Aberrant Regeneration
Lid Lag on Downgaze
• Congenital Ptosis -Levator Maldevelopment
• Graves Ophthalmopathy
• Surgery, Trauma
• Aberrant Regeneration of 3rd
-pseudo von Graefe’s phenomenum
Primary Aberrant Regeneration?
• Motility problems like those described above without an acute third nerve palsy preceding them.
• Suggestive of a cavernous sinus mass
Trochlear Nerve• Superior Oblique
• Long course of nerve from posterior midbrain to orbit
Midbrain
Fourth Nerve PalsyNote head tilt
4th Nerve Palsy
• Diplopia –usually vertical
• Sometimes Cyclo-diplopia
• Head tilt and/or turn
• Diplopia can worse or better on downgaze
• Findings can evolve over time
Fourth Nerve Palsy
• Hypertropia
• Overaction of Ipsalateral Inferior Oblique Muscle
• Underaction of SO not often obvious
• Excyclotorsion
• Incommitant
Fourth Cranial Nerve PalsyIncommitance
• Hypertropia• Hypertropia worse on contraleral gaze• Hypertropia worse on ipsalateral head tilt
• E.g. “right – left - right”• or “left - right – left”
Right- Left- Right
2 RHT 7 RHT 18 RHT
15 RHT 3 RHT
Three Step Test is only valid for
Neurologic and not mechanical muscle problems
Assumes only one paretic muscle
Think in terms of a paretic muscle
DX: Left SO palsy
Excylotorsion
• With red maddox rod over Right and white over Left
Shows a right excylcotorsion consistent with a right SO palsy
Fourth Nerve Palsy
• Congenital*
• Traumatic
• Microvascular
• Neoplasm
• Aneurysm – not common
• Other
* Congenital – often decompensate later in life with “sudden” onset of diplopia, will have large vertical fusional amplitudes
Fourth Nerve Palsy(Traumatic)
Upshoot in adduction characteristic of
Overaction of left inferior oblique
Upshoot in Adduction
• Most Commonly IOOA
• DVD
• Duane’s Syndrome
Right Fourth Nerve Palsy
Bilateral Fourth Nerve Palsy
• Alternating Hypertropia
e.g. LHT in right gaze
RHT in left gaze
• Large Excyclotorsion >10-15 degrees
• V pattern
Vertical Misalignment
• Fourth Nerve Palsy• Graves Disease• Post-operative muscle problem• Skew Deviation• Third Nerve Palsy –inferior or superior division
• Brown’s Syndrome• Other Orbital Disease• Plus More
Management of Isolated Fourth Nerve Palsy
• Usually no work up necessary as most cases are traumatic or congenital. If no history of trauma or signs of congenital palsy then :
• Does patient have vasculopathic risk factors?
• Yes: Observe• No: Medical evaluation, maybe image
Abduction DeficitNew onset diplopia
Patient asked to look
To the left
Abduction Deficit
• Sixth Cranial Nerve Palsy• Graves Ophthalmopathy• Myasthenia Gravis• Orbital – tumor, inflammatory• Duane’s Syndrome Type I• Medial Wall Fracture• Past LR recession• More!
What’s this abduction deficit due to?
Patient had R+R OS for Exotropia, why does she have decreased abduction?
Agenesis of sixth nerve nucleus and , with abberent innervation of the Lateral Rectus muscle by branches third cranial nerve, hence multiple motility problems can be seen
Duane’s Type I Type II Type III
Duane’s Syndrome
Duane’s Syndrome
• For Example Duane’s Type I loss of abduction, often esotropic (no diplopia)
variable loss of adduction
narrowing of fissure on attempted abduction
upshoot or downshoot in attempted adduction
possible
Sixth Nerve Palsy
• Microvascular• Neoplastic (Posterior Fossa, Orbit, Cavernous sinus, etc)
• Trauma• Increased Intracranial Pressure• Aneurysm• Post-viral and post-immunization• Other – MS, Syphilis, PML• Undetermined
Sixth Nerve Palsies in Children*:
1. Tumors 45% 2. Increased ICP (15%) non-tumor 3. Traumatic 12% 4. Congenital 11%
5. Inflammatory 7% 6. Miscellaneous 5% (post-immunization,
post-viral) 7. Idiopathic 5%
• * JPOS; 1999; 36: 305
Brainstem Syndromeswith Sixth Cranial Nerve Palsy
• Foville’s Syndrome* - - lesion in region of sixth nerve nucleus - ipsalateral gaze palsy, facial palsy, loss of taste, Horner’s Syndrome, facial anesthesia, deafness
• Millard-Gubler Syndrome – Sixth and contralateral hemiparesis
PrimaryClosing Lids
Looking Left
What’s Wrong?
Where is at least one lesion?
Pontine CVA?
Pontine CVA
Insert MRI scan of Eutenaurer
Total Ophthalmoplegia, loss of vision and ptosis OD
• Cavernous sinus tumor probable meningioma
Multiple Cranial Nerve Palsies(3,4,6, etc)
• Superior Orbital Fissure Syndrome• Suspect Orbital Inflammatory Process –pseudotumor, and cellulitis (think fungal)• Cavernous SinusThrombosis• Orbital or Cavernous sinus tumor• Vascular: AV fistulas or aneurysms• Invasive Periorbital Skin Cancers with perinerual spread• GCA• Diabetic• Other: HZO, Mucocele, Wernicke’s encephalopathy, • Guillain-Barre or Miller Fisher Syndromes
Cranial Nerve PalsyHistory
DM, HTN, CV disease
Neurologic disease
Shunting procedures
Pain
Age
Cranial Nerve PalsyExam
• Standard Eye Exam, but also include:
• Exophthalmetry
• Checking other cranial nerve function (5,7,8) – COMPANY THEY KEEP
Cranial Nerve PalsyMajor Considerations
• Microvascular
• Trauma
• Neoplastic
• Aneurysm
• Congenital
• Other: GCA, Sarcoid
• Consider: MS and Myasthenia
General Approach to CN Palsies
• Other Localizing signs
• Pupils
• Pain
• Progression
• FOLLOW-UP, microvascular palsies resolve usually in about 2 months
Matching
• Millard-Gubler
• Weber’s
• Miller Fisher
• Duanes
• Benedikt’s
• III
• IV
• VI
• Multiple CN