Diagnostic value of the fast-FLAIR sequence in MR imaging of intracranial tumors

The aim of this study ws to quantify imaging characteristics of fast fluid- attenuated inversion recovery (FLAIR) sequence in brain tumors compared wit h T1-postcontrast- and T2-sequences. Fast-FLAIR-, T2 fast spin echo (FSE)-, and T1 SE post-contrast images of 74 patients with intracranial neoplasms were analyzed. Four neuroradiologists rated signal intensity and inhomogene ity of the tumor, rendering of cystic parts, demarcation of the tumor vs br ain, of the tumor vs edema and of brain vs edema, as well as the presence o f motion and of other artifacts. Data analysis was performed for histologic ally proven astrocytomas, glioblastomas, and meningiomas, for tumors with p oor contrast enhancement and for all patients pooled. Only for tumors with poor contrast enhancement (n = 12) did fast FLAIR provide additional inform ation about the lesion. In these cases, signal intensity, demarcation of th e tumor vs brain, and differentiation of the tumor vs edema were best using fast FLAIR. In all cases, rendering of the tumor's inner structure was poo r. For all other tumor types, fast FLAIR did not give clinically relevant i nformation, the only exception being a better demarcation of the edema from brain tissue. Artifacts rarely interfered with evaluation of fast-FLAIR im ages. Thus, fast FLAIR cannot replace T2-weighted series. It provides addit ional information only in tumors with poor contrast enhancement. Irt is hel pful for defining the exact extent of the edema of any tumor but gives litt le information about their inner structure.