The facial nerve (facial nerve), which has the longest bony canal among the nerves that move muscles in the body, is one of the most frequently paralyzed nerves. Approximately 90% of these paralysis cases occur due to diseases within the temporal bone where the nerve passes through its canal. While the most common cause of facial paralysis is Bell’s palsy, a self-limiting disease, it should be noted that pathologies such as inflammations causing bone damage or tumors originating from the middle ear can also cause paralysis. Since the treatment of diseases in this region falls under otolaryngology, patients diagnosed with facial paralysis must undergo ENT evaluation.<\/p>\n
After exiting the brain, some nerve fibers of the facial nerve that reach the upper half of the face continue to the same side, while others cross over to the opposite side. In contrast, all nerve fibers that control the lower half of the face cross over and stimulate the facial muscles on the opposite side. Therefore, in cases of pathology occurring on one side of the brain, the lower half of the face on the opposite side is affected, whereas the upper face remains unaffected because it receives stimulation from the healthy brain on the same side. These types of paralysis are referred to as \u201ccentral facial paralysis,\u201d while paralysis caused by pathologies in the brainstem and lower regions are called \u201cperipheral facial paralysis.\u201d This finding is significant in differential diagnosis; however, it should not be forgotten that in peripheral pathologies of the nerve, stimulation of the upper half of the face may still be preserved.<\/p>\n
After exiting the temporal bone, the facial nerve travels alongside the auditory and vestibular nerves, entering the temporal bone. In pathologies within this region, known as the inner ear canal, hearing and balance complaints can accompany facial paralysis.<\/p>\n
While traversing the canal within the temporal bone, the facial nerve gives branches that stimulate the tear glands, control the muscles of the malleus in the middle ear, provide taste sensation to the anterior two-thirds of the tongue, and activate the submandibular salivary glands. After exiting the temporal bone, the nerve extends forward and branches into those that stimulate the facial muscles by passing through the parotid salivary gland.<\/p>\n
Facial paralysis findings such as the presence or absence of tear secretion, taste sensation on the tongue, and function of the malleus are helpful in determining the affected region of the nerve.<\/strong><\/p>\n Table of Contents<\/p>\n<\/span><\/div>\n