Test: Cranial Nerve III

Video Link

Background/Purpose

Procedure

Cranial Nerve III is the motor nerve for the muscle levator palpebrae and the muscles eye movement: medial rectus (medial), inferior rectus (inferior), superior rectus (superior) and inferior oblique (inferior and medial). It is also responsible for the pupil constriction with light. Identifying pupils are PERRLA (pupils equal, round and reactive to light and accommodation) and testing corresponding eye movements by standing one meter in front of the patient and asking the patient to follow a target with eyes only, and not the head while moving the target in an "H" shape, testing accommodation of the pupil when the gaze shifts from far to near and performing the uncover/cover test looking for pupillary constriction will identify ptosis and nystagmus if present.
Performed: Bilaterally

Dialog

Occulomotor nerve exam

Criteria

• smooth conjugate movement of eyes in all directions
• Appropriate pupil response and constriction to light
• pupil constriction with accommodation

Measurement

0.00

LOINC Code

0

Scale/Grading

Pass/Fail