It runs laterally and forward to the internal auditory meatus where it enters the facial canal with the nervus intermedius. The upper zygomatic branch supplies the frontalis, upper lid orbicularis oculi, corregator supercilli and procerus. The lower zyqomatic branch supplies the lower lid orbicularis. The nervus intermedius gives off the greater petrosal nerve which carries parasympathetic secretary fibers to the lacrimal gland. With paralysis or palsy of the nerve, the function of these muscles are weakened.
Emotional movements are unimpaired.
B. Peripheral lesions - The upper and lower facial muscles are equally affected in voluntary and emotional movements Clinical Signs Patients with facial nerve palsy develop flattening of the entire face with loss of forehead wrinkles, infraorbital fold and nasolabial fold. Medical Management Many patients can be managed medically with topical lubrication drops and ointment, moisture chambers, and taping the eyelids closed at bedtime. Lateral Tarsorraphy - Lateral closure of the eyelids will frequently suffice to narrow the palpebral fissure and decrease evaporation. Under local anesthesia a 5-6mm triangle of tarsus and conjunctiva is removed from the lateral aspect of the upper eyelid. A 5mm piece of tarsoconjunctiva is advanced from the lower eyelid and sutured into this defect.