[TA] highly variable opening between the medial portion of the posterior border of the greater wing of the sphenoid bone (posterior to foramen ovale) and the medial portion of the anterior border of the petrous part of the temporal bone; it may be seen as a wide, lateral extension of the foramen lacerum in the dry skull, or it may be closed, especially laterally, taking the form of a petrosphenoidal suture rather than a fissure. SYN: fissura sphenopetrosa [TA], sphenopetrosal fissure.