Which examination finding would suggest a CN X lesion?

The examination finding that suggests a CN X (vagus nerve) lesion is the deviation of the uvula. The vagus nerve plays a crucial role in the motor control of the muscles of the soft palate and is responsible for the elevation of the uvula during swallowing. When there is a lesion or dysfunction of the vagus nerve, one side of the soft palate may fail to elevate properly, leading to the uvula deviating toward the unaffected side. This is a classic clinical sign utilized in neurological assessments to identify possible cranial nerve damage.

While difficulty swallowing may suggest a problem with the vagus nerve, it is not specific enough as this can be associated with lesions of other cranial nerves as well. Loss of facial sensation is associated with the trigeminal nerve (CN V), and throat pain may occur due to various conditions but does not specifically indicate a vagus nerve issue. Therefore, uvula deviation serves as a more direct and specific indicator of a problem with CN X.