Magnetic resonance imaging of clival chordomas.

Chordoma of the clivus is one of the skull base tumors which originate from the remains of the notochord. The magnetic resonance findings in six patients are reported. The tumors showed slightly low intensity on T1 weighted images, but high intensity on T2 weighted images. The localization of the tumor was easily recognized by the disappearance of the normal signal in the clivus. Compression of the pons and medulla oblongata was readily diagnosed on sagittal images. A normal pituitary gland was demonstrated in all cases. Magnetic resonance imaging was useful for the diagnosis and for the surgical treatment of these chordomas.