ocular motility ii kenn freedman m.d.. supranuclear cranial nerves extra-ocular muscles

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