Flashcards in Oculomotor Disorders Deck (32):
Clinical presentation of CNIII palsy?
1. Sudden onset of binocular horizontal, vertical, or oblique diplopia
2. Ptosis or a droopy eyelid
3. 25% are idiopathic
What is a major complication of congenital CNIII palsy?
Why might pt with congenital CNIII palsy not complain of double vision?
because they have suppressed vision in the affected eye
What would you find on the eye exam for CNIII palsy?
1. partial or complete ptosis
2. dilated, and poorly or nonreactive pupil
3. Deficits in adduction, elevation and depression (EOMs)
What is considered a complete impairment of CN III?
1. Impairment in the majority of the functions in the muscles of the eye that are controlled by cranial nerve III
Complete III nerve palsies are associated most commonly with what kind of eye movement?
large-angle exotropia and hypotropia (down and out) and Ptosis.
How can we rule out if compressive lesion is affecting CNIII?
It will almost always involve the pupil
Ischemic palsy is different from a tumor how?
Will usually not involved the pupil
If complete impairment of CNIII with pupil affected what do we do?
If complete impairment without affected pupil what do we do?
watch for 3 months
If incomplete impairment of CNIII what do we do?
Hallmark of Complete CN 3 Palsy??
Ptosis with down and out movement
What else should be in the diff with CN3 symtpoms?
What is our goal in treating CNIII palsy?
goal is to maximize visual function, including ocular alignment
Why is CN IV so prone to injury from blunt head trauma or compression (ICP, brain tumors, swelling)?
Its long course coming from the back of the head
Clinical presentation of CN IV?
1. vertical diplopia/ tortional diplopia
2. objects in primary position or in downward gaze will be double
3. PATIENT MAY TILT HEAD TO SIDE TO BE ABLE TO SEE BETTER
If a patient is experiencing CNIV palsy which side will their head be tilting?
head tilting to the side opposite the paralyzed muscle
Where will the eye be pointing in cranial nerve IV palsy?
ability to rotate downward is weak because of superior oblique muslce
IN CNIV palsy where is deviation the greatest?
when gaze is directed toward the weak muscle = greater hypertropia
Hallmark signs of CN4 palsy?
head tilt and nasal upshoot
What else should be in the differential for CN IV palsy?
1. Vasculopathic (13%)
2. Tumor (10%) (2.8%)
3. Trauma (54%)
If imaging is normal in a suspected CNIV nerve palsy what should the next step be?
Lumbar puncture may be warranted in patients who have normal imaging studies but are suspected of having subarachnoid space lesions.
What disease often affects the 6th cranial nerve?
Clinical presentation of CNVI palsy?
horizontal diplopia that worsens with gaze with gaze laterally
-strabismus present right away with gaze to lateral side but could later present in straight forward gaze
Where will the affected eye be deviated in CNVI palsy?
primary position is esotropia (crossed eyed/buried eye)
Hall mark sign of CN VI palsy?
In all cranial palsies where is the eye's primary position/deviation?
Away from the movement of the eye
(moves eye downward then eye will stay up)
In all cranial nerve palsies where is the deviation the worst?
When the gaze is toward the injured muscle
What else should be in the Diff for CNVI?
3 plus some subcategories
3. Elevated cranial pressure
If it persists for more beyond 6-12 months what do we do?
In what cases should imaging be done immediately?
Neuroimaging to exclude neoplasm
focal signs or papilledema are present
What are some treatments that could be used for CNVI palsy?
1. alternate patching,
2. prism therapy,
3. strabismus surgery, and
4. botulinum toxin.