Final answer:
The inability to smile on the left side and corresponding Bell's phenomenon suggest left facial nerve damage with an ipsilateral lesion.
Step-by-step explanation:
If a patient cannot smile on the left side and the left eyeball rotates upward (Bell's phenomenon), it may be indicative of left facial nerve damage, specifically an ipsilateral lesion. This means that the lesion is on the same side as the symptoms presented. Bell's phenomenon is an upward and outward movement of the eye that occurs when one tries to close the eyes but can't due to facial nerve paralysis. The facial nerve, also known as cranial nerve VII, controls the muscles of facial expression, and its damage is therefore evident through asymmetric facial expressions and movement.