Susceptibility mapping in malignant cerebral tumors

Phase maps of the brain were constructed using two partial-saturation sequences (without a 1800 refocusing pulse) with values of time differing by 80 or 160 msec. These maps depicted changes due to inhomogeneities in Bo as well as changes in tissue susceptibility. In 36 patients with histologically proven (28) or clinically and radiologically suspected tumors (eight), local changes in susceptibility were detected in 16 cases. The susceptibility changes probably represent recent or post hemorrhage. These changes may also account for the low-intensity rim seen between tumor and edema with T2-dependent spin-echo sequences