Cranial Nerves Overview

A patient who cannot identify an odor on each side of the nose, normally, has diminished olfactory function.

The sense of smell is decreased bilaterally with aging.

Which of the following may be a cause of anosmia (loss of smell)? (Select all that apply)

What does the test looking for when examining the ocular fundus using an ophthalmoscope?

Palpable fissures are usually equal in width and nearly so.

Which of the following is an abnormal pupillary finding?

Pupillary constrictriction is a normal pupillary finding.

Ptosis (drooping) occurs with myasthenia gravis, cranial nerve pressure, or Horner syndrome.

Increasing intracranial pressure causes a sudden, unilateral, dilated, and nonreactive pupil.

Which of the following is NOT a cause for ptosis?

Cranial Nerves

Cranial nerves are a set of 12 paired nerves that emerge from the brain
Each nerve has a specific number, name, and function
They are responsible for various sensory and motor functions throughout the body

Cranial Nerve I - Olfactory Nerve

Type: Sensory
Function: Smell
Normal Range of Findings: Normally a person can identify an odor on each side of the nose. Smell is mostly decreased bilaterally with aging. Any asymmetry in the sense of smell is important.
Abnormal Findings: Air passages are occluded with upper respiratory infection or sinusitis. Anosmia—decrease or loss of smell occurs bilaterally with tobacco smoking, allergic rhinitis, COVID-19, and cocaine use.

Cranial Nerve II - Optic Nerve

Type: Sensory
Function: Vision
Normal Range of Findings: Test visual acuity and visual fields by confrontation (see Chapter 15). Using the ophthalmoscope, examine the ocular fundus to determine the color, size, and shape of the optic disc (see Chapter 15).
Abnormal Findings: Visual field loss (see Table 16.6, p. 316). Papilledema with increased intracranial pressure. Optic atrophy (see Table 15.9, p. 320).

Cranial Nerves III, IV, and VI - Oculomotor, Trochlear, and Abducens Nerves

Function: Eye movement
Normal Range of Findings: Check pupils for size, regularity, equality, direct and consensual light and accommodation (see Chapter 15).
Abnormal Findings: Ptosis (drooping) occurs with myasthenia gravis, intracranial nerve III problem, or Horner syndrome (see Table 15.2, p. 312). Increased intracranial pressure causes a sudden, unilateral, dilated, and non-reactive pupil.

This quiz covers the 12 cranial nerves, focusing on their functions, including sensory and motor roles. You’ll explore details about specific nerves such as the Olfactory and Optic nerves, including normal and abnormal findings related to each. Perfect for students who need a comprehensive understanding of cranial nerve functions.