19 Neurological Flashcards
When are all 5 divisions of facial nerve present in fetus
By 8th wk gestation
How does course of FN differ in adults and kids
At birth, FN is located superficially within poorly formed mastoid; with maturation, the nerve is displaced medially and inferiorly
When is myelination of individual axons of the facial nerve complete
age 4
What prognostic info does electroneurography (ENoG) provide for facial paralysis
Patients with 95% degeneration or greater have a 50% chance of unfavorable recovery; if at least 10% function is retained in the first 21 days of paralysis, 80–100% functional recovery is highly likely.
When is ENoG meaningful
Between days 3 and 21 (14) after complete loss of voluntary fnc
What is the next most accurate test when ENoG is unavailable
Maximal stimulation test
What test should be performed when 100% neural degeneration is recorded with ENoG
Voluntary EMG recording; regenerating nerve fibers conducting at different rates can result in an overestimation of neural degeneration on ENoG
What should be done if motor unit potentials are detected on EMG
No further rx is indicated
What EP test is more useful 3 wks after onset of complete facial paralysis
EMG
What test should be performed on AFro-Caribbean migrants with idiopathic faical nerve palsy
HTLV-1 antibody screen
What is incidence of cranial nerve palsy at initial presentation in pts with NP CA
12-18%
T/F: True diplopia should resolve with 1 eye closed
true
Small irregular pupils that react irregularly to light but better to accomodation suggests what ID?
Neurosyphillis
What is Myerson sign
Persistent blinking when the forehead is tapped repeatedly is an abnl manifestation of glabellar reflex, a primitive reflex seen in infants that may be a sign of frontal lobe dz in adults
Which cranial nerves are tested with corneal reflex?
V and VII IPSI
VII CONTRA
