FIG 1. Bright cerebellum on diffusion-weighted images as the initial finding after cerebral anoxia.

A, Axial T2-weighted image, 3300/105/1 (TR/TE/excitations), obtained within 3 hours of cardiac arrest, shows the cerebellum to be of normal appearance.

B, Corresponding high-strength diffusion-weighted image, 0.8/123/1100 (TR/TE/B value), shows that the cerebellum (c) is diffusely bright when compared with the left occipital lobe (o).

C, Follow-up image obtained 3 days after anoxic episode. Midsagittal T1-weighted image (570/15/1) shows swollen cerebellum with upward transtentorial and downward transforaminal herniations. The forth ventricle and brain stem are compressed.

D, Axial T2-weighted image (3500/93/1), obtained at same time as the image shown in C, shows swollen and bright cortex, effaced cortical sulci, and bright basal ganglia. Because of technical problems, diffusion-weighted images were not obtained as part of the follow-up study. This patient died.