MR fluid-attenuated inversion recovery imaging as routine brain T2-weighted imaging

We tried to investigate if magnetic resonance (MR) fluid-attenuated inversion recovery (FLAIR) imaging can be used as a routine brain screening examination instead of spin-echo T2-weighted imaging. Three hundred and ninety-four patients with clinically suspected brain diseases were randomly selected and examined with both brain MR FLAIR and T2-weighted imaging on the axial plane. These two imaging techniques were evaluated by two neuroradiologists as to which imaging was better for routine brain T2-weighted imaging. In 123 of 394 cases (31%), FLAIR imaging was superior to spin-echo T2-weighted imaging. Especially in cases with inflammatory diseases, traumatic diseases and demyelinating diseases, FLAIR imaging was particularly useful. Small lesions bordering cerebrospinal fluid (CSF) are often detected only by FLAIR imaging. In 259 cases (66%), including 147 normal cases (37%), they were equally evaluated. Only in 12 cases (3%) was conventional T2-weighted imaging superior to FLAIR imaging. Cerebrovascular lesions like cerebral aneurysm and Moyamoya disease could not be detected on FLAIR images because these structures were obscured by a low signal from the CSF. Also, because old infarctions tend to appear as low signal intensity on FLAIR images, the condition was sometimes hard to detect. Finally, FLAIR imaging could be used as routine brain T2-weighted imaging instead of conventional spin-echo T2-weighted imaging if these vascular lesions were watched.