Advanced Health Assessment Practice Exam

Which instruction should a nurse give to assess cranial nerves III, IV, and VI?

1. “Close your eyes tightly.”

2. “Follow my finger with only your eyes.”

3. “Look straight ahead and do not move your eyes.”

4. “Focus on a nearby object.”

The correct answer is: “Follow my finger with only your eyes.”

To assess cranial nerves III (Oculomotor), IV (Trochlear), and VI (Abducens), the most appropriate instruction is to "Follow my finger with only your eyes." This directive allows the nurse to evaluate the movement of the eyes and the function of these cranial nerves effectively. Cranial nerve III is responsible for most eye movements, controlling the majority of the extraocular muscles, including the upper eyelid. Cranial nerve IV controls the superior oblique muscle, allowing for downward and inward eye movement, while cranial nerve VI governs the lateral rectus muscle, facilitating lateral eye movement. By asking the patient to follow a finger with their eyes, the nurse can assess for smooth tracking, any strabismus, and overall coordination of extraocular movements, which are crucial functions of these cranial nerves. The other options do not assess eye movement effectively. Closing the eyes tightly does not provide any information about eye motion or innervation. Telling the patient to look straight ahead restricts assessment of lateral and vertical eye movements. Focusing on a nearby object does not specifically evaluate the range of motion and coordination of the extraocular muscles controlled by these cranial nerves. Therefore, the instruction to follow the finger is