Pterygopalatine Fossa Flashcards
Pterygopalatine fossa
The pterygopalatine fossa is a small area deep in the skull between the maxilla and sphenoid bone
PTERYGOMAXILLARY FISSURE
It’s a narrow space that lies between the
tuberosity of the maxilla anteriorly and the pterygoid process of the sphenoid posteriorly. It is the entrance from the infratemporal fossa to the more medial located pterygopalatine fossa.
Pathways of Pterygopalatine fossa
- infratemporal fossa - pterygomaxillary fissure
- middle cranial fossa - foramen rotundum
- base of the skull - pterygoid canal
- orbit - inferior orbital fissure
- nasal cavity - sphenopalatine foramen
- oral cavity (palate) - greater palatine canal
- nasopharynx - lesser palatine canal and pharyngeal canal
Sphenopalatine foramen
Found on the medial wall of the pterygopalaitne fossa, it is formed by a small notch in the upper
part of the perpendicular plate of the palatine bone where it joins the sphenoid bone
Contents of Pterygopalatine fossa
Primary Structures in the pterygopalatine fossa are:
• Maxillary Artery
• Maxillary nerve
• Pterygopalatine ganglion
Maxillary Artery
In Pterygopalatine fossa
The maxillary artery leave the infratemporal fossa and enters the pterygopalatine fossa through the pterygopalatine fissure
Pterygopalatine part of the maxillary artery
- Alveolar artery branches
- Infraorbital artery
- Descending palatine artery
- Sphenopalatine artery
Alveolar artery branches
Supply upper teeth, maxillary sinus & gums
Infraorbital artery
Supplies mid portion of the face
Descending palatine artery
Divides into greater and lesser branch to supply the hard and soft palates
Sphenopalatine artery
Passes through the sphenopalatine foramen to
supply the posterior portions of the nasal cavity
Maxillary Nerve
Maxillary Nerve (V2) is entirely sensory. It enters the pterygopalatine fossa posteriorly through the foramen rotundum and gives off multiple branches that convey sensory neurons from the nasal cavity, palate, nasopharynx, maxillary teeth and skin of the mid-face.
Branches of Maxillary Nerve
- zygomatic nerve
- infraorbital nerve
- ganglionic branches
- greater and lesser palatine branches
- posterior superior nasal branches (medial & lateral) & nasopalatine
- pharyngeal branches
Zygomatic nerve
Supplies skin over the cheek
Infraorbital nerve
Supplies skin of the mid-face
Alveolar nerves
Supplies the maxillary teeth
Greater and lesser palatine nerves
Supplies the hard ans soft palates
Nasal nerves
Supplies the posteroinferior part of nasal covity
Pharyngeal nerves
Supplies the nasopharynx
Pterygopalatine Ganglion
It is the largest of four parasympathetic ganglia in the head. It lies within the pterygopalatine fossa
where it is attached to the maxillary nerve by the latter’s two ganglionic branches.
The nerve of the pterygoid canal
It brings preganglionic parasympathetic fibers
(from the greater petrosal nerve) and postganglionic sympathetic fibers (from the deep petrosal nerve) to the ganglion.
Sympathetic fibers
Located in Pterygopalatine Fossa
The sympathetic fibers pass through the ganglion without change and travel
with the branches of the maxillary nerve to their destinations
Parasympathetic fibers
Located in Pterygopalatine Fossa
The preganglionic parasympathetic fibers synapse in the pterygopalatine ganglion. The now postganglionic fibers attach themselves (as “hitch hikers”) to branches of the maxillary nerve that distribute them to the minor salivary glands of the hard and soft palate, the small glands of the nasal cavity and the upper pharynx.
Lacrimal Gland Innervation
After synapsing in the pterygopalatine ganglion, postganglionic neurons travel first in the Zygomatic nerve then join the Lacrimal nerve via a communicating branch that is located in the lateral side of the orbit.
Nose
It’s comprised of the external nose and the nasal cavities (paired)