RESUMO
Objective To evaluate contrast-enhanced fluid-attenuated inversion recovery (FLAIR) imaging in the detection of leptomeningeal lesions.Methods Seventeen patients with a variety of leptomeningeal lesions were analyzed.The MRI protocol included un-enhanced and contrast-enhanced FLAIR images and contrast-enhanced T_1WI,Comparisons between contrast-enhanced FLAIR images and T_1WI and between un-enhanced and contrast-enhanced FLAIR images were made to determine which sequence better depicted the lesions.Results Leptomeningeal lesions showed as either diffusely or locally abnormal hyper-intensity along sulci or cistern on three sequences.Comparison between contrast-enhanced FLAIR and T_1WI showed that only contrast-enhanced FLAIR revealed the abnormalities in 7,both revealed the abnormalities but the former was superior in 2 ,and both were conspicuous in 7. In 1 patient of tuberculous meningitis,diffuse abnormalities of sulci were shown only on contrast-enhanced FLAIR, abnormalities of cisterns were shown on both sequences but the former was superior.Comparison between un- enhanced and contrast-enhanced FLAIR showed that only contrast-enhanced FLAIR revealed the abnormalities in 9,both revealed the abnormalities but the former was superior in 3,and both were conspicuous in 4. In 1 patient of tuberculous meningitis,abnormalities of cisterns were shown only on contrast-enhanced FLAIR,diffuseabnormalities of sulci were shown on both sequences but the former was superior.Conclusions Contrast-enhanced FLAIR images were superior to un-enhanced FLAIR images and contrast-enhanced T_1WI in the detection of leptomeningeal lesions. Contrast-enhanced FLAIR images are helpful and should be considered when findings on un-enhanced FLAIR images and/or contrast-enhanced T,WI are inconclusive.