Selecting the optimal plane for CT examination of the base of the skull.

We examined 50 computed tomographic (CT) scans that included sections through the base of the skull at a wide variety of angles. Each of these examinations had an accompanying localizing radiograph so that the angle at which the scan had been obtained could be ascertained . The scans were randomly arranged and rated as to how well 11 structures in the skull base were visualized: (1) foramen magnum, (2) foramen ovale, (3) cribriform plate, (4) vidian canal, (5) carotid-jugular septum, (6) lateral margin of the clivus, (7) hypoglossal canal , (8) pterygomaxillary space, (9) occipital condyle, (10) jugular tubercle, and sphenooccipital synchondrosis (when present).