FIG 4. Images from the case of a 70-year-old man with a streptococcus abscess, recent history of acute dizziness, and focal seizures.

A, T2-weighted spin-echo image is consistent with the diagnosis of glioblastoma or necrotic metastasis.

B, Contrast-enhanced T1-weighted spin-echo image is consistent with the diagnosis of glioblastoma or necrotic metastasis.

C, On the diffusion-weighted echo-planar image, however, the "necrotic" area shows high signal intensity (arrow).

D, On the ADC map, very low ADC values (0.29 e^-3 mm²/s) are found (arrow). Such behavior was never present in the necrotic parts of gliomas (compare with fig. 3D and E) or metastases and may be highly specific for abscess formation