Examination of CN1 Flashcards
What 3 things are involved in examining CN 1?
1) Observation of external nose
2) Observation of Internal Nasal passageway.
3) Checking sense of smell
How to check sense of smell?
Occluded one nasal and ask patient to close eyes.
Use non-irritating smell that patient can identify.
Check other nostril using a second smell.
Anosmia in both nostrils - common causes?
Blocked nasal passages, common cold, trauma, relative loss with aging.
Is CN 1 a true nerve?
No, it is a fiber tract of the brain
CN 1 ‘s peripheral and intermediate connections consist of ________, __________, and _____ neurons.
Primary
Secondary
tertiary
These neurons are gathered into branches and pass through the cribriform plate to the olfactory bulb.
Primary neurons
Are primary neurons myelinated?
No, they are unmyelinated
About how many branches are primary neurons gathered into?
20
What make up secondary neurons?
Myelinated processes of bipolar neurons of the olfactory bulb.
Secondary neurons form what and terminate where?
Olfactory tract
Terminate in primary olfactory cortex
What makes up the primary olfactory cortex?
periamygdaloid area
prepiriform cortex
Tertiary neurons extend from what area?
Primary olfactory cortex
Tertiary neurons terminate where?
entorhinal cortex, lateral pre-optic area, amygdaloid body, and medial forebrain bundle.
Entorhinal cortex is which Broadmann area?
Area 28
Associations fibers to the tegmentum and pons pass directly as ____ order neurons from what?
3rd
Anterior perforating substance
