Foramen rotundum

Exit foramen · CN V2

A round opening in the greater wing of the sphenoid, just below and behind the medial end of the superior orbital fissure, that leads from the middle cranial fossa into the pterygopalatine fossa. It carries the maxillary division alone.

Traced from the start

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

Detail

Transmits
Maxillary nerve (V2) only
Leads to
Pterygopalatine fossa, where V2 gives its palatine, nasal and zygomatic branches and the pterygopalatine ganglion hangs from it

When it goes wrong

Perineural spread of a palatal or maxillary carcinoma back along V2 through the foramen

Progressive numbness of the cheek and upper lip advancing to V1 and V3 territories and the cavernous sinus, seen as nerve thickening and foramen widening on MRI

Practise this structure

1 question in the bank tagged Trigeminal Nerve.