Petrous cephalocoele Case 1Case 2Case 3 Incidental finding of a CSF filled structure in the petrous apex (blue arrow). The cephalocoele was contiguous with Meckel's cave (red arrow). A 50-year-old patient presentd with right sided trigeminal neuralgia. CT showed a well demarcated excavation of the right petrous apex. The cavity was filled with CSF with no enhancement of diffusion restriction. A 60-year-old patient presented with headache. CT showed a well-marginated lesion remodelling the right petrous apex. MRI did not show any abnormal soft tissue or enhancement with only CSF signal content.