Transsphenoidal basilar skull fracture

Transsphenoidal basilar skull fractures are a particularly serious type of basilar skull fracture usually occurring in the setting of severe traumatic brain injury and with potential for serious complications including damaging the internal carotid arteries and optic nerves as well as high incidence of dural tear with CSF leak. Venous thrombosis complicates up to 31% of these fractures, as many as 75% of caroticocavernous fistulae will have antecedent skull base fractures.

Pathophysiology

Due to the particulars of the anatomy of the base of skull, fractures that involve the sphenoid sinus tend to extend along a number of predefined pathways :

Anterior transverse
  • impact: lateral in the region of the temple
  • coronal fracture plane
    • extending from the squamous temporal bone
    • through the base of the anterior clinoid processes anterior to the pituitary fossa
    • continuing laterally along the contralateral sphenotemporal buttress +/- into squamous temporal bone
  • may extend inferiorly to involve the pterygoid processes
Lateral frontal diagonal
  • impact:  lateral frontal/anterior malar eminence
  • oblique fracture plane
  • often associated with maxillary sinus fractures and lateral orbital wall
Posterior transverse
Mastoid diagonal