Expansion
Thin as paper, tear beneath, that's the pterion's deadly teeth
Mnemonic
“Pterion, the temple of doom”: the junction of four bones at the thinnest part of the skull.
- F - Frontal
- P - Parietal
- T - Temporal, squamous part
- S - Sphenoid, greater wing
The anterior division of the middle meningeal artery runs immediately deep to it, so a blow here causes an extradural haematoma, classically with a lucid interval followed by deterioration.
Surface marking: about 4 cm above the zygomatic arch and 3 cm behind the frontal process of the zygomatic bone, roughly two finger breadths above the arch and a thumb’s breadth behind the orbital margin.
Expansion
- Pterion - thinnest point of the skull vault
- Middle meningeal artery - runs just beneath it