Foramen ovale

Exit foramen · CN V3

An oval opening in the greater wing of the sphenoid, posterolateral to the foramen rotundum, leading from the middle cranial fossa to the infratemporal fossa. It carries the mandibular division with the lesser petrosal nerve, the accessory meningeal artery and an emissary vein linking the cavernous sinus to the pterygoid plexus (OVALE).

Traced from the start

  1. Pons
  2. Trigeminal nerve (CN V)
  3. Foramen ovale

Detail

Transmits
Mandibular nerve (V3), lesser petrosal nerve (IX, to the otic ganglion), accessory meningeal artery, emissary vein
Leads to
Infratemporal fossa, where the otic ganglion sits on the medial side of V3 immediately below the foramen

When it goes wrong

Percutaneous treatment of trigeminal neuralgia (radiofrequency rhizotomy, glycerol injection, balloon compression) passing a needle through the foramen ovale to the trigeminal ganglion

Pain relief at the cost of facial numbness in the treated division, and anaesthesia dolorosa or corneal anaesthesia if V1 is included

Infection tracking from the pterygoid plexus to the cavernous sinus through the emissary vein

Cavernous sinus thrombosis after dental or deep facial sepsis

Practise this structure

1 question in the bank tagged Trigeminal Nerve.