Axial FLAIR and sagittal T1-WIs demonstrate diffuse calvarial thickening. Note also the
involvement of the clivus and the anterior arch of C1. Did you notice the significant basilar
invagination and narrowing of the foramen magnum? If one draws a line between the
posterior hard palate and the opisthion (Chamberlain's line), the tip of the dens should
not extend above this line by more than 2 to 3 mm. In this case, the dens would extend
above this line by several mm. Also present is probable chronic small vessel disease
of the deep white matter.
Axial CT filmed in bone windows nicely demonstrates the diffuse calvarial
thickening associated with prominent bony trabeculae.
Key words: calvarium
Paget's disease of the skull