Infratemporal Fossa

Question 1

Muscles of mastication

Answer 1

• Muscles of mastrication innervated by V3
• Lateral pterygoid m: Protrusion, depression of mandible
  
  • S. head: attaches to meniscus
  • I. head: attaches to neck of condyle
• Medial pterygoid m: Elevates mandible
• Temporalis: elevates mandible
• Masseter (lies outside of infratemporal fossa): Elevates mandible

Question 2

Pterygomaxillary fissure

Answer 2

• important opening b/w infratemporal fossa & pterygopalatine fossa

Question 3

Major branches of maxillary artery

Answer 3

• divided into 3 parts by lateral pterygoid

1st part

• Middle meningeal br.
• S. Temporal br.
• I. Alveolar br.

2nd part

• muscular branches

3rd part starts as artery passes through pterygomaxillary fissure

• Post. S. alveolar

Question 4

Pterygoid venous plexus

Answer 4

Receives:

• Middle meningeal v.
• branches from roof of oral caivty, nasal caivty, all teeth, paranasal sinuses, muscles of infratemporal fossa
• branch from I. Ophthalmic V.

Drains into:

• Facial v. to IJV
• Maxillary v. to Retromandibular V.

Communicates with:

• cavernous sinus via I. Ophthalmic & Emissary v.v.
  *

Question 5

V3 branches

Answer 5

Anterior division

• muscular br. to pterygoids, masseter, temporalis
• (Long) buccal: general sensory from mucosa of cheek

Posterior division

• Auriculotemporal br.: general sensory from auricle, lateral scalp & parasympathetics
• I. Alveolar br: general sensory from mandibular teeth & motor
• Lingual br. before Chorda Tympani: General sensory only from ant. 2/3rd of tongue
• Lingual br. after Chorda Tympani: Taste from ant. 2/3rd of tongue & parasympathetics to submandibular & sublingual glands
• Nerve to mylohyoid: motor to mylohyoid & Ant. Belly of Digastric
• I. Alveolar br.: sensory
• Mental br.: sensory

Question 6

Lymphatic drainage of head & neck

Answer 6

Cervical “collar” nodes

• face & scalp drain into cervical “collar” nodes
  
  • Parotid: ant/lat scalp, upper face
  • Submandibular: face, tongue, mouth
  • Submental: chin, tongue tip, mouth
• mastoid & occipital nodes drain into Superficial cervical nodes (along Ext. Jugular V.)
• other “collar” nodes drain into deep cervical nodes
  
  • form chain along IJV
  • Jugulodigastric node: post. tongue, tonsils, deep neck
  • Juguloomohyoid node: ant. tongue, deep neck
  • S. group drains into I. group
  • I. group drains into Jugular trunk
• Retropharyngeal, paratracheal, & infrahyoid nodes
  
  • drain middle ear, paranasal sinuses, nasal cavity, pharynx, trachea, thyroid, post. oral cavity
  • drain into jugulodigastric or deep cervical nodes