PMC8443378_01
PMC8443378_02
Axial (a) and midsagittal (b) noncontrast head CT at presentation shows bilateral cerebellar hemisphere hypoattenuation (low density) with swelling (arrows). There is inferior herniation of the cerebellar tonsils with crowding at the foramen magnum (dashed arrow).
CRICC2021-9449565.001.jpg
PMC8443378_02_CRICC2021-9449565.001.jpg
fig1
A head CT was performed, and he was found to have bilateral cerebellar hemisphere hypoattenuation with acute swelling on computed tomography (Figure 1).