Nucleus of facial nerve

Fibers course:

• Fibers of facial nerve course superiorly around the abducens nuc. ("internal genu")

• First they course dorsomedially towards the floor of 4th ven. to loop behind the abducens nuc.

  • The loop (internal genu of CN7) elevates the floor of 4th ven. and forms the facial colliculus;

• then course ventrolaterally passing between the nucleus of their origin and nuc. of spinal tract of CN5;

• Emerge through the PMJ on the ventral aspect of the brainstem lat. to the emergence of the abducent nerve.

Target:

• Muscles of facial expression, platysma, buccinator, stapedius muscle

• Posterior belly of digastric;

• Stylohyoid muscle