Pterygopalatine fossa anatomy

Maxillary nerve (V2)

The maxillary nerve (V2) is purely sensory. It originates as the second division of the trigeminal ganglion in the cranial cavity, travels through the foramen rotundum, and enters the pterygopalatine fossa. At the pterygopalatine fossa, the maxillary nerve (V2) gives rise to the zygomatic nerve, the posterior superior alveolar nerve, and two ganglionic branches, while its main trunk continues into the inferior orbital fissure as the infraorbital nerve.

The ganglionic branches allow the maxillary nerve (V2) to communicate with the pterygopalatine ganglion, thus serving as a conduit for parasympathetic and sympathetic postganglionic fibers to travel through. Along with the sensory fibers of the maxillary nerve (V2), these fibers (sympathetic and parasympathetic) either leave directly from the pterygopalatine ganglion as orbital, palatine, nasal, and pharyngeal branches, or from the maxillary nerve (V2) along with its associated branches.

Collectively, the branches of the maxillary nerve and the pterygopalatine ganglion supply the:

• sphenoidal, ethmoidal and maxillary sinuses
• nasal cavity
• nasopharynx
• roof of the oral cavity
• upper teeth and their associated structures
• skin over the temple
• cheekbone
• lower eyelid
• lateral aspect of the nose
• upper lip

The zygomatic nerve, being one branch of particular importance, carries parasympathetic postganglionic fibers from the pterygopalatine ganglion to supply the lacrimal gland.

Learn more about the maxillary nerve with our study unit:

Pterygopalatine ganglion

The pterygopalatine ganglion is the largest of the four parasympathetic ganglia located in the head. At the pterygopalatine fossa, it sits inferior to the maxillary nerve (V2) and anterior to the opening of the pterygoid canal. The pterygopalatine ganglion houses the cell bodies of parasympathetic postganglionic neurons, and receives parasympathetic preganglionic fibers and sympathetic postganglionic fibers from the nerve of the pterygoid canal.

The nerve of the pterygoid canal is formed by the union of the greater petrosal nerve (branch of facial nerve (VII)) and the deep petrosal nerve (branch of carotid plexus); it thus carries parasympathetic preganglionic fibers of the greater petrosal nerve and sympathetic postganglionic fibers of the deep petrosal nerve. Once formed, the nerve of the pterygoid canal leaves the middle cranial fossa, travels through the pterygoid canal via the foramen lacerum, and enters the pterygopalatine fossa to join the pterygopalatine ganglion.

Note that only the parasympathetic preganglionic fibers of the nerve of the pterygoid canal synapse at the pterygopalatine ganglion, while the sympathetic postganglionic fibers travel through it. In addition, the maxillary nerve (V2) is purely sensory and thus has no autonomic function; however, it is used as a vehicle by parasympathetic and sympathetic fibers to reach their targets.

Pterygopalatine ganglion anatomy is discussed in detail in this article.

Maxillary artery

The maxillary artery is one of the major branches of the external carotid artery. It originates near the neck of the mandible, travels through the pterygomaxillary fissure via the infratemporal fossa, and enters the pterygopalatine fossa as the terminal part of the maxillary artery.

At the pterygopalatine fossa, it is located anterior to the pterygopalatine ganglion and gives rise to six branches that accompany the branches of the maxillary nerve [V2] and the pterygopalatine ganglion. These branches are the:

• posterior superior alveolar
• infraorbital
• greater palatine
• pharyngeal
• sphenopalatine
• artery of the pterygoid canal

Together, these branches supply the nasal cavity, the roof of the oral cavity, and all the upper teeth. They also contribute to the blood supply of the sinuses, the oropharynx, and the floor of the orbit.

Solidify your knowledge about the maxillary artery:

Veins

Veins that drain the areas supplied by the branches of the terminal part of the maxillary artery travel with these branches back into the pterygopalatine fossa. They then continue through the pterygomaxillary fissure and join the pterygoid plexus in the infratemporal fossa.

Pterygomaxillary fissure

The pterygomaxillary fissure is located between the anterior and posterior wall of the pterygopalatine fossa. It communicates with the infratemporal fossa and transmits the posterior superior alveolar nerve and the maxillary artery.

Foramen rotundum

The foramen rotundum is located on the posterior wall of the pterygopalatine fossa, superior to the pterygoid canal. It communicates with the middle cranial fossa and from there, it transmits the maxillary nerve (V2).

Pterygoid canal

The pterygoid canal is located on the posterior wall of the pterygopalatine fossa, between the foramen rotundum and the palatine canal. It communicates with the middle cranial fossa and from there, it transmits the nerve, artery, and vein of the pterygoid canal.

Palatovaginal canal

The palatovaginal canal is located on the posterior wall of the pterygopalatine fossa, inferior to the pterygoid canal. It communicates with the nasal cavity and transmits the pharyngeal branches of the maxillary nerve and artery.

Inferior orbital fissure

The inferior orbital fissure is located on the superior border of the pterygopalatine fossa. It communicates with the orbit and transmits the zygomatic nerve and the infraorbital artery and vein.

Palatine canal

The palatine canal is located inferiorly at the pterygopalatine fossa. It communicates with the oral cavity via the greater palatine and the lesser palatine canals, which transmit the greater palatine and lesser palatine nerves, respectively. The palatine canal also transmits the greater palatine artery.

Sphenopalatine foramen

The sphenopalatine foramen is located on the medial border of the pterygopalatine fossa. It communicates with the lateral wall of the nasal cavity and transmits nasal nerves and the sphenopalatine artery.