From the case:
Tympanosquamosal fissure
Axial non-contrast

Prominent petrotympanic fissure on the right.
From the case:
Tympanosquamosal fissure
Axial bone window

The arrow shows the tympanosquamosal fissure which is the lateral continuation of the petrotympanic fissure.
Case Discussion
Prominent petrotympanic fissure not to be confused with a fracture.