Cranial nerves are twelve pairs of nerves that emanate from the nervous tissue of the brain. What is the abbreviation used to refer to them?

• A. CN
• B. EOMI
• C. DTRs
• D. Focal neuro deficit

Answer: (A)

The key idea is the standard shorthand used for nerves in medical notes: cranial nerves are referred to by the abbreviation CN, with the plural form CNs when talking about the whole set. This concise label is widely used because there are twelve pairs that originate from the brain, labeled CN I through CN XII, so saying “CNs” quickly communicates you’re talking about the cranial nerves as a group.

The other terms aren’t abbreviations for the nerves themselves. EOMI refers to extraocular movements intact and is a description from a neuro exam; DTRs means deep tendon reflexes; a focal neuro deficit describes a localized neurological impairment.