Cranial Nerve VII Palsy

Cranial Nerve VII Palsy
SYMPTOMS Dry eyes, Epiphora, Decrease in vision due to exposure keratopathy
SIGNS Loss of forehead wrinkling, Drooping of mouth, Brow ptosis, Inability to fully close eyelids, Upper lid retraction, Lower lid paralytic ectropion, Increase laxity of the eyelids, Lagophthalmos, Decreased tear production, Conjunctival injection, Exposure keratopathy (Signs of chronic exposure include pannus, corneal thinning, corneal infiltrates, corneal epithelial defects, and corneal ulcers)
Decrease in corneal sensitivity (Associated with cranial nerve V involvement) can exacerbate complications seen with exposure keratopathy
WORK-UP Pupils | EOMs | Full eye exam with dilation | Eyelid/ptosis testing (MRD1, MRD2, Levator excursion test, etc.) | Exophthalmometry | Cranial nerve testing (Especially concentrating on cranial nerve 7) | NaFl staining | Schrimer test | Evaluation of Bell’s phenomenon
TREATMENT -Treat any meibomian gland dysfunction that is present -Use artificial tears -Use lubricating ointment such as Refresh PM ¼ inch ribbon QHS -Consider using tape to close eyelids, especially when sleeping or wearing moisture chamber goggles -Consider punctal plugs if there is no lower lid malposition
Consider an amniotic membrane to help with complications from exposure keratopathy
Consider scleral lenses which are a good long-term solution for exposure keratopathy
Consider Doxycycline 50mg PO 1 tab bid (Decrease MMPs) and Vitamin C 1g PO qd
Consider adding autologous serum 20-40% concentration
If treatments are not effective, refer patient to an oculoplastic specialist for further evaluation and treatment (tarsorrhaphy, etc.)
Refer to a neuro-ophthalmologist/neurologist if the following is noted: · There is no improvement of the facial palsy over 2-3 weeks · Progression of facial palsy is noted over a period of 3 weeks · The facial palsy is complete · The facial palsy had a gradual onset · There is involvement of other cranial nerves · Recurrent facial palsies
FOLLOW-UP If treating patient for sequelae of an acute facial palsy, evaluate in 1 week in order to monitor signs/symptoms and to determine if referral to a neurologist/neuro-ophthalmologist is needed
If treating patient for sequelae of a chronic/longstanding facial palsy, evaluate in 1-2 weeks in order to monitor for improvement in signs/symptoms
ADDITIONAL LAB | TESTS MRI of the brain with and without contrast
ETIOLOGY Central palsy (Lesion that involves the pons): Typically caused by a stroke, brain tumor, or head trauma. Other cranial nerves could be involved with central palsie
Peripheral palsy (Lesion that involves the facial nerve pathway): Typically caused by Bell’s palsy (most common), Ramsay-Hunt syndrome, head trauma, or brain tumor.
If only the lower facial muscles are involved, this would indicate a lesion that involves the contralateral upper motor neuron. If the lower and upper facial muscles are involved, this would indicate a lesion that involves the ipsilateral lower motor neuron (most common)
DIFFERENTIAL DX Cranial nerve V palsy, Facial injury, Forceps delivery, Birth trauma, Neurosyphilis
NOTES Bell’s palsy accounts for 51% of cases of all facial nerve palsies. The onset is sudden (< 72 hours) and only involves one side of the face. The etiology is idiopathic but the herpes simplex virus may be involved. It is more common in patients who are diabetic, immunocompromised, pregnant, or have respiratory disease. About 70-80% of patients experience spontaneous recovery within 2-3 weeks. Complete resolution, however, can take months with about 13-16% of patients never fully recovering
Current practice guidelines recommended starting oral steroids within 72 hours of a Bell’s palsy in patients over the age of 16 years old, but this is somewhat controversial and debated
Aberrant innervation can typically be seen with longstanding or recovering facial palsies (especially a Bell’s palsy). The most common ones are ocular-oral synkinesis and crocodile tear syndrome
Patients with lyme disease experience a facial nerve palsy about 10% of the time with 25% of cases being bilateral
Ramsay Hunt syndrome: Very painful vesicles and sudden hearing loss with a facial nerve palsy secondary to Herpes Zoster

Leave a Comment

You must be logged in to post a comment.