A patient came into the clinic due to an eye problem. Which of the following is a correct method to assess the function of the patient's cranial nerve II (optic nerve)?
Explanation
• Cranial nerve II, the optic nerve, has a sensory function that carries impulses for vision. It travels to the cerebrum, where visual impulses are perceived and interpreted.
• Damage to the optic nerve would affect vision, and the effects would depend on the location of the lesion. Homonymous hemianopsia means a person may not see things on either the left or the right side of the visual field. Bitemporal hemianopsia results in difficulty seeing things in the outer visual field.
• Use a Snellen chart to assess for visual acuity and to check the function of cranial nerve II, the optic nerve. Another test to check this nerve would be checking the visual field in the four quadrants.
• Incorrect: The options to use a penlight and to assess for nystagmus are associated with the function of cranial nerves III, IV, and VI (oculomotor, trochlear, and abducens).
• Incorrect: Corneal reflex is associated with CN V, the trigeminal nerve.