Figure 1:

Preoperative head magnetic resonance (a: T2-weighted images and b: gadolinium-enhanced T1-weighted images) and computed tomography images (c: left, axial images; right, sagittal images). (a and b) The cystic tumor tumoral lesion is located on the left side of the clivus, showing ring enhancement with gadolinium contrast. The lesion extends into the intracranial space, compressing the brain stem and left internal carotid artery (white arrowhead: internal auditory canal, white arrow: internal carotid artery). (c) The tumor has invaded the left side of the clivus.