A tumor of which cranial nerve is commonly associated with dizziness?

A tumor of which cranial nerve is commonly associated with dizziness?

• A. Cranial Nerve VIII (CN VIII)
• B. Cranial Nerve II (CN II)
• C. Cranial Nerve IV (CN IV)
• D. Cranial Nerve VII (CN VII)

Answer: (A)

Dizziness points to disruption of balance pathways, most directly the vestibular portion of CN VIII, which carries balance information from the inner ear to the brain. A tumor on CN VIII, such as a vestibular schwannoma (acoustic neuroma), commonly arises at the internal auditory canal or cerebellopontine angle and compresses the vestibular nerve fibers. This leads to vertigo or dizziness, imbalance, and often unilateral sensorineural hearing loss with tinnitus. The other nerves listed aren’t primarily involved in balance: the optic nerve governs vision; the trochlear nerve controls a single eye muscle and causes diplopia with misalignment; the facial nerve governs facial movement and other functions. Thus, CN VIII best explains dizziness.

Dizziness points to disruption of balance pathways, most directly the vestibular portion of CN VIII, which carries balance information from the inner ear to the brain. A tumor on CN VIII, such as a vestibular schwannoma (acoustic neuroma), commonly arises at the internal auditory canal or cerebellopontine angle and compresses the vestibular nerve fibers. This leads to vertigo or dizziness, imbalance, and often unilateral sensorineural hearing loss with tinnitus. The other nerves listed aren’t primarily involved in balance: the optic nerve governs vision; the trochlear nerve controls a single eye muscle and causes diplopia with misalignment; the facial nerve governs facial movement and other functions. Thus, CN VIII best explains dizziness.