Table of Contents


  • A cuboidal open chamber
  • Anatomical borders:
    • Superior
      • Sphenoid bone/sinus
    • Anterior
      • Posterior end of nasal septum & choanae
    • Posterior
      • Clivus & C1-2 vertebral bodies
    • Inferior
      • Roof of soft palate
  • The eustachian tube opens into the lateral wall
    • Posterior to eustachian tube entrance there is a cartilagous protuberance = TORUS RUBARIUS
    • Posterior to torus tubarius, there is a recess = FOSSA OF ROSENMULLER
  • Pharyngobasilar fascia in lateral and posterior walls
  • NPC can invade intracranially and along cranial nerve, or along base of skull foramens
  • The most important are the foramen lacerum and the foramen ovale
  • Forman Oval
    • In greater wing of sphenoid bone
    • Posterolateral to Forman Rotundum
    • What pass through Foramen Ovale? EASY —> REMEMBER OVALE:
      • O —> Otic Ganglion
      • V —> V3 (third branch of trigeminal n.)=Mandibular n.
      • A —> Accesory Meningial a.
      • L —> Lesser petrosal n. (sometime)
      • E —> Emissary Veins (from Sinus Cavernous)

Know about Sinus Cavernous

  • Sinus Cavernous located lateral to sella Turcica
  • What pass through Sinus Cavernous? EASY —> Nerves: 3,4,5,6+Carotid ( Just remember when you say 5 you mean V1 and V2 NOT V3 ) —> You already know that V3 pass through foramen ovale
    • Oculumotor ( Nerve III )
    • Trochlear ( Nerve IV )
    • Abducens ( Nerve VI )
    • Ophthalmic (V1)
    • Maxillary (V2)
      • This pass through the inferior portion and exits VIA FORAMENE ROTUNDUM
  • So now you should be able to know the exit foramen of all branches of Trigemo.
    • V1 —>Sinus Cavenous —> Superior orbital Fissure
    • V2 —>Sinus Cavernous —> Foramen Rotundum —> Pterygopalatine Fossa
    • V3 —> Foramen Ovale

Want to know more about Pterygopalatine Fossa?

Carotid a.
o Optic nerve lies just above and outside the cavernous sinus, superior and lateral to the pituitary gland on each side, and enters the orbital apex via the optic canal.
• Want to know more about Foramen Rotundum?
o Ant and Med of sphenoid bone
o Maxillary Nerve (V2) pass through it.

o Foramen Ovale and Formaen Lacerum are in close anatomic relationship with the cavernous sinus and hence cranial nerves III to VI

 Respiratory-type ciliated epithelium
o variable degrees of squamous metaplasia
o rich in lymphatic
 Lymphatic 3 pathways from Nasopharynx:
o Parapharyngeal space
 in close proximity to cranial nerves IX to XII
 The uppermost node is the retropharyngeal node called the node of Rouviere
o Jugular chain(jugulodigastric) + deep jugular nodes
o Spinal accessory chain