The aim of this study was to analyze the CT and MR features of multiple gli
oblastomas, and to determine the best imaging modality for the initial diag
nosis. The CT (four exams) and MR imaging (eight exams) of eight patients w
ith proven multiple glioblastomas were reviewed by two neuroradiologists. T
he lesions were always hypo- or isodense on CT and hyperintense on T2-weigh
ted images (100 %). They were usually hypo- or isointense on T1-weighted im
ages (90 %). Edema and mass effect were very variable. After contrast media
administration, the enhancement was mostly strong (71% on CT and 70 % on M
R), often either heterogeneous or ring-like. The different lesions of a pat
ient often had a different pattern on MR (75% of cases). Meningeal or ventr
icular enhancement, suggestive of a possible way of dissemination, was rare
. In case of multiple cerebral masses, multiple glioblastomas should be con
sidered as a possible diagnosis in addition to the better known diagnosis o
f brain metastases, abscesses, or multifocal lymphomas. Moderate edema and
mass effect on MR associated with strong and heterogeneous enhancement are
suggestive of feature of multiple glioblastomas. Magnetic resonance allows
rarely the visualization of a dissemination route.