A lesion of the facial nerve after it exits from the stylomastoid foramen would result in what?

A lesion of the facial nerve after it exits from the stylomastoid foramen would result in what?

• A. An ipsilateral loss of taste to the anterior tongue
• B. A sensory loss to the tongue
• C. An ipsilateral paralysis of facial muscles
• D. A contralateral paralysis of facial muscles

Answer: (C)

A lesion of the facial nerve after it exits from the stylomastoid foramen primarily affects the branches of the facial nerve responsible for motor control of the facial muscles. Since the facial nerve has already exited the skull and is in the region where it innervates the muscles of facial expression, a lesion at this point would lead to paralysis of those muscles on the same side of the face as the lesion, resulting in an ipsilateral paralysis of the facial muscles. This paralysis can manifest through an inability to perform facial expressions such as smiling, closing the eye, or frowning on the affected side. The facial nerve is responsible for the movements of the facial musculature, and any damage to it impacts these motor functions directly. While the other options discuss aspects of taste and sensory functions, these are not the primary consequences of a lesion in this area of the facial nerve. Taste sensation to the anterior two-thirds of the tongue is mediated by the chorda tympani branch of the facial nerve, which may be affected but is secondary to the primary motor function impacted by the lesion. Similarly, there is no contralateral effect since the facial nerve’s motor control is ipsilateral; thus, those options relate to functions that are less affected or not applicable

A lesion of the facial nerve after it exits from the stylomastoid foramen primarily affects the branches of the facial nerve responsible for motor control of the facial muscles. Since the facial nerve has already exited the skull and is in the region where it innervates the muscles of facial expression, a lesion at this point would lead to paralysis of those muscles on the same side of the face as the lesion, resulting in an ipsilateral paralysis of the facial muscles.

This paralysis can manifest through an inability to perform facial expressions such as smiling, closing the eye, or frowning on the affected side. The facial nerve is responsible for the movements of the facial musculature, and any damage to it impacts these motor functions directly.

While the other options discuss aspects of taste and sensory functions, these are not the primary consequences of a lesion in this area of the facial nerve. Taste sensation to the anterior two-thirds of the tongue is mediated by the chorda tympani branch of the facial nerve, which may be affected but is secondary to the primary motor function impacted by the lesion. Similarly, there is no contralateral effect since the facial nerve’s motor control is ipsilateral; thus, those options relate to functions that are less affected or not applicable