Anatomy clinical correlates: Temporal regions, oral cavity and nose

The face is made up of a large network of nerves, vessels, muscles, and other structures which are susceptible to disease. In particular, there are many clinical conditions that affect the temporal region, oral cavity, and nose. Understanding the anatomy of these areas can help us better understand the clinical presentation, complications and management of these conditions. So let’s get face to face with our… well, face!

First up, the parotid gland. Remember that the facial nerve enters the parotid gland to form the parotid plexus and give rise to the temporal, zygomatic, buccal, marginal mandibular, and cervical branches. However, these branches don't actually innervate the gland but just pass through it to exit at its borders. The auriculotemporal nerve, which is a branch of the mandibular nerve, courses superficially to the gland and is responsible for general sensation of the gland. Additionally, parasympathetic innervation from the glossopharyngeal nerve travels with the auriculotemporal nerve to innervate the parotid gland.

Now, understanding these anatomical relationships is also important when it comes to surgery to the parotid gland, as the majority of salivary gland tumors occur within the parotid gland which are often surgically removed. During parotid gland surgery, the surgeon needs to identify, dissect, and isolate the facial nerve and its branches with great care, so that there’s no damage to them. See, if the nerve or one of its branches is damaged, that causes paralysis of some or all facial muscles on that side. The auriculotemporal nerve also requires special care to avoid damaging it during surgery, because during healing the nerve can go on to reinnervate into the sweat glands of the overlying skin. So instead of salivating when eating or thinking about food, this reinnervation causes excessive sweating and redness of the cheek during the normal parasympathetic response. This condition is called Frey syndrome.