EOMs Flashcards
Superior Oblique Muscle
#1 - internal rotation #2 - depression (adducted position) #3 - abduction (lateral rotation)
Innervated by fourth nerve/trochlear.
Inferior Oblique Muscle
#1 - external rotation #2 - elevation #3 - adduction
Innervated by the inferior branch of the oculomotor (III) nerve.
Medial Rectus Muscle
Innervated by the inferior division of the oculomotor (III) nerve.
Lateral Rectus Muscle
It is the only muscle supplied by the abducens nerve, cranial nerve VI.
Superior Rectus Muscle
#1 - elevation (primary) #2 - intorsion #3 - adduction
Innervated by the superior division of the oculomotor nerve.
Inferior Rectus Muscle
#1 - depresses #2 - extorts #3 - adducts
Innervated by the inferior division of oculomotor nerve (Cranial Nerve III).
Right ______ nerve palsy shows right hyperdeviation that worsens on left gaze, right head tilt, and downgaze, with relative excyclotropia of the right eye.
FOURTH
superior oblique muscle
Brown’s Syndrome
Tendon sheath problem.
- limited elevation (especially during adduction)
Duane Syndrome Type I
Limited ABDUCTION with possible compensatory head turn towards affected side. Most common!
eg. DT1 OS, head turn toward left
Duane Syndrome Type II
Limited ADDUCTION with possible compensatory head turn towards unaffected side.
Duane Syndrome Type III
Limited ADDUCTION and ABDUCTION. Usually presents with head turn towards the affected side.
CN most likely to be affected by trauma?
CN 4 - trochlear
Only one to exit the dorsal aspect of the brainstem and is the ocular motor nerve with the longest course. Most susceptible to trauma.
Common causes of CN 4 palsy?
Congenital and trauma
Most common CN palsy?
CN 6
Causes of CN 6 Palsy
- tumours
- increased intracranial pressure
- Horner’s syndrome
- trauma
System causes should resolve in 3 months, if not imaging should be done.
