Which cranial nerve is assessed using a Snellen chart and pupil light reflex?

Which cranial nerve is assessed using a Snellen chart and pupil light reflex?

• A. Optic
• B. Olfactory
• C. Vestibulocochlear
• D. Accessory

Answer: (A)

This item centers on how the optic nerve mediates vision and the pupil light reflex. A Snellen chart measures visual acuity by assessing how well the eye can resolve letters, which depends on the optic nerve transmitting retinal information to the brain. The pupil light reflex involves detecting light and triggering constriction, with the optic nerve providing the afferent signal to the brain so the reflex can be coordinated, and the oculomotor nerve carrying the efferent signal to constrict the pupil. So the nerve being assessed by both tests is the optic nerve. The other nerves listed don’t govern vision or this reflex: olfactory handles smell, vestibulocochlear handles hearing and balance, and the accessory nerve controls neck and shoulder movements.

This item centers on how the optic nerve mediates vision and the pupil light reflex. A Snellen chart measures visual acuity by assessing how well the eye can resolve letters, which depends on the optic nerve transmitting retinal information to the brain. The pupil light reflex involves detecting light and triggering constriction, with the optic nerve providing the afferent signal to the brain so the reflex can be coordinated, and the oculomotor nerve carrying the efferent signal to constrict the pupil. So the nerve being assessed by both tests is the optic nerve. The other nerves listed don’t govern vision or this reflex: olfactory handles smell, vestibulocochlear handles hearing and balance, and the accessory nerve controls neck and shoulder movements.