Figure 18.

Normal coronal anatomy of the central skull base and trigeminal nerve. Post-gadolinium T1 coronal fat saturation, high resolution sequence performed at 3 Tesla with reconstructions through the cavernous sinus (a) and further posteriorly through Meckel’s cave (b). The normal right V1 (dashed white arrow) and V2 (dotted white arrow) nerves are seen as low signal structures surrounded by the vividly enhancing cavernous sinus. Other cranial nerves are visible. The left V3 is seen (white arrow) as it exits through the FO surrounded by an enhancing perineural vascular plexus. Where PIT = pituitary, SS = sphenoid sinus and NP = nasopharynx. The cerebrospinal fluid-filled Meckel’s cave (MC: solid white arrow) contain the U-shaped and enhancing trigeminal ganglion (TG: dotted white arrow). High signal flowing blood is seen in the ICA as it extends superiorly into the foramen lacerum (open white arrow). FO: foramen ovale; ICA: internal carotid artery.