Muscles of Facial Expression Flashcards
WHat muscle around the eye closes the eye?
Orbicularis Oculi
What muscle around the eye furrows the brow?
Corrugator Supercilii
What muscles are around the nose that are involved in facial expression?
Dilator Nares
Compressor Nares
Procerus
What muscles are around the mouth that are involved in facial expression?
Obicularis Oris Zygomaticus Major and Minor Depressor Angularis Oris Levator labii superioris Depressor Labii inferioris Rizorius Buccinator Platysma
All muscles of facial expression are derived from what?
Mesoderm of 2nd branchial or pharyngeal arch
All muscles of facial expression are innervated by what?
Branches of CN VII Temporal Zygomatic Buccal Marginal Mandibular Cervical
What muscle is NOT involved in facial expression that is supplied by CN III?
Levator Palpebrae Superioris
The levator palpebrae superioris has a smooth muscle (tarsal) component which is innervated by what?
Sympathetic fibers which arise from stellate ganglion
What muscle has dual innervation?
Frontalis
What does it mean that the frontalis has dual innervation?
Each muscle is seperately innervated by branches of the facial nerves that arise from both sides of the brain.
Dual innervation allows what?
Differentiation of an upper motor neuron lesion from a lower motor neuron lesion of the 7th CN to be made.
In an upper motor neuron lesion of CN 7 (caused by stroke) the pt is able to do what?
Raise the eyebrow on affected side
In a lower motor neuron lesion of CN 7 (bells palsy) the pt is NOT able to do what?
Raise eyebrow on affected side
In bells palsy the muscles of the face on the affected side will be what?
Paralyzed
When the muscles are paralyzed in bells palsy the patient will have the inability to do what?
Close eyelids (orbicularis oculi)
Smile (rizorius)
Whistle (buccinator and orbicularis oris)
Blink eye reflexively
