Leptomeningeal and calvarial sarcoidosis: CT and MR appearance.

We report an unusual case of biopsy-proven combined leptomeningeal and calvarial sarcoidosis, as seen on CT and MRI. A solitary large thick plaque was present in the left hemisphere, with overlying bony infiltration and erosion and associated abundant vasogenic edema in the brain. The lytic lesion was visible on Scout digital radiography for CT slice positioning. The typical manifestations of CNS sarcoidosis, i.e., chronic leptomeningitis in the basilar cisterns and hypothalamic regions, were absent.