Investigation of the calcification at the petroclival region through Multi-slice Computed Tomography of the skull base

PPCL calcifications cannot be differentiated from PSL calcifications in MSCT slices. The distinction can be easily done in 3-D views. The presence of ossified ligaments may make surgeries in this region difficult, and special care has to be taken to avoid injuries to structures which pass under these ossified ligaments. Particularly in elderly patients, the appropriate surgical instrument for the PSL calcifications should be prepared preoperatively. If PSL is calcified, 6th cranial nerve palsy may not occur even though increased intracranial pressure syndrome is present. Whereas, in lateral trans-tentorial herniations, 3rd cranial nerve palsy occurs in earlier periods when PSL is calcified. Moreover, in subtemporal and transtentorial petrosal approaches, knowing the PSL calcification preoperatively is important to avoid damaging the 6th cranial nerve during surgery.