Infratemporal Fossa

Question 1

Infratemporal fossa: what, where + function

Answer 1

Wedge-shaped space, base of skull, below temporal fossa
Close to temporal + pterygopalatine
Passage for neurovascular structures, cranial cavity

Question 2

Infratemporal fossa: roof

Answer 2

Greater wing, inf. surface
Opens sup. to temporal fossa
Contains:
*foramen ovale
*foramen spinosum
*petrotympanic fissure

Question 3

Infratemporal fossa: anterior wall

Answer 3

Post. surface maxilla

Alveolar foramen

Question 4

Infratemporal fossa: lateral wall

Answer 4

Med. surface ramus

Mandibular foramen

Question 5

Infratemporal fossa: medial wall

Answer 5

Lat. plate pterygoid process = ant.
Pharynx & tensor + levator veli palatini = post.
Pterygomaxillary fissure = opening to fossa

Question 6

Infratemporal fossa: contents

Answer 6

Sphenomandibular ligament
Lat. pterygoid
Med. pterygoid
Maxillary a.
Mandibular n.
Chorda tympani br. of facial n.
Pterygoid venous plexus

Question 7

Mandibular nerve: origin, course + types of fibres

Answer 7

Largest division of trigeminal
Sensory + motor component
All branches = in infratemporal fossa
Sensory + motor root = from trigeminal ganglion, exit via foramen ovale
Outside skull, roots join

Question 8

Mandibular nerve: main trunk

Answer 8

3 motor:
*n. to med. pterygoid
*n. to tensor veli palatini
*n. to tensor tympani
1 sensory:
*nervus spinosum = small meningeal br.

Question 9

Mandibular nerve: anterior trunk

Answer 9

3 motor:
*masseteric n.
*deep temporal n.
*lateral pterygoid
1 sensory:
*buccal n.

Question 10

Mandibular nerve: posterior trunk

Answer 10

3 sensory:
*inf. alveolar n.
*lingual n.
*auriculotemporal n.
1 motor:
*n. to mylohyoid = br. of inf. alveolar

Question 11

Mandibular nerve: mnemonic

Answer 11

My Tendency To Nap, Must Definitely Leave Bed, In Life Always Move

Question 12

Lingual nerve: course + innervation

Answer 12

Course:
*Btw. tensor + lat. pterygoid
*Joined by chorda tympani
*Lat. surface of med. pterygoid
*Enters oral cavity, crosses submandibular duct
*Enters tongue, lat. surface hyoglossus
*Attached submandibular ganglion
*In ganglion, preganglionic para with postganglionic
GVA:
*ant 2 thirds tongue
*oral mucosa in floor cavity
*lingual gingivae

Question 13

Inferior alveolar nerve: course + innervation

Answer 13

Course:
*deep lat. pterygoid
*lat. surface med. pterygoid
*mylohyoid n.
*mandibular canal via foramen
GVA:
*lower teeth + gingivae
*mucosa
*skin of chin + lower lip
SVE:
*mylohyoid
*ant. belly digastric

Question 14

Chorda tympani: course + innervation

Answer 14

Course:
*from facial n. in temporal bone
*enters infratemporal fossa through petrotympanic fissure
*deep to lat. pterygoid
*joins lingual - hitchhikes
*oral cavity
*in ganglion = preganglionic sympathetic with postganglionic parasympathetic
SVA:
*taste ant. 2 thirds tongue
GVE:
*parasympathetic innervation of sublingual + submandibular glands

Question 15

Pterygopalatine fossa: location, structure + contents

Answer 15

Inverted teardrop, lat. skull
Extends from infratemporal to nasal via sphenopalatine foramen
V2 enters via foramen rotundum, branches, leaves via IOF
Pterygopalatine ganglion = preganglionic parasympathetic from facial with postganglionic, join V2
Nerve of pterygoid canal enters, canal runs through pterygoid process of sphenoid
Walls = sphenoid, maxilla + palatine

Question 16

Maxillary nerve in pterygopalatine fossa

Answer 16

Enters via foramen rotundum
Passes through:
*zygomatic, leaves IOF
*post. sup. alveolar, via alveolar foramen
*2 ganglionic branches, pass through ganglion
Nerves exiting ganglion:
*orbital
*nasal, via sphenopalatine foramen
*greater + lesser palatine, via palatine canal
*pharyngeal, via palatovaginal/pharyngeal canal
Nerve of pterygoid canal:
*union greater petrosal = from facial & deep petrosal = from int. carotid plexus
*enters fossa at canal
*greater = preganglionic parasympathetic
*deep = postganglionic sympathetic