Corpus: Greater petrosal nerve

The greater petrosal nerve is a parasympathetic branch of the facial nerve that splits off in the area of the geniculate ganglion.

The greater petrosal nerve leaves the facial nerve at the geniculate ganglion and passes through the hiatus for the greater petrosal nerve. It exits the cranial cavity through the foramen lacerum. Together with fibers from the deep petrosal nerve, it then forms the nerve of the pterygoid canal (Vidian nerve) and travels through the pterygoid canal of the sphenoid bone to the pterygopalatine fossa. Here, it connects with the pterygopalatine ganglion. From this ganglion, its fibers continue with branches of the maxillary nerve to innervate the glands of the mucous membranes of the palate and nose, as well as the lacrimal gland (via lacrimal anastomosis).

The greater petrosal nerve contains preganglionic parasympathetic fibers originating from the superior salivatory nucleus, which join the facial nerve via the intermediate nerve. It also connects to the tympanic plexus through a communicating branch.