Comparison of post-contrast 3D-T 1 -MPRAGE, 3D-T 1 -SPACE and 3D-T 2 -FLAIR MR images in evaluation of meningeal abnormalities at 3-T MRI.

OBJECTIVE: This study was to assess the usefulness of newer three-dimensional (3D)-T1 sampling perfection with application optimized contrast using different flip-angle evolutions (SPACE) and 3D-T2 fluid-attenuated inversion recovery (FLAIR) sequences in evaluation of meningeal abnormalities.

METHODS: 78 patients who presented with high suspicion of meningeal abnormalities were evaluated using post-contrast 3D-T2 -FLAIR, 3D-T1 magnetization-prepared rapid gradient-echo (MPRAGE) and 3D-T1 -SPACE sequences. The images were evaluated independently by two radiologists for cortical gyral, sulcal space, basal cisterns and dural enhancement. The diagnoses were confirmed by further investigations including histopathology.

RESULTS: Post-contrast 3D-T1 -SPACE and 3D-T2 -FLAIR images yielded significantly more information than MPRAGE images (p < 0.05 for both SPACE and FLAIR images) in detection of meningeal abnormalities. SPACE images best demonstrated abnormalities in dural and sulcal spaces, whereas FLAIR was useful for basal cisterns enhancement. Both SPACE and FLAIR performed equally well in detection of gyral enhancement. In all 10 patients, where both SPACE and T2 -FLAIR images failed to demonstrate any abnormality, further analysis was also negative.

CONCLUSION: The 3D-T1 -SPACE sequence best demonstrated abnormalities in dural and sulcal spaces, whereas FLAIR was useful for abnormalities in basal cisterns. Both SPACE and FLAIR performed holds good for detection of gyral enhancement. Post-contrast SPACE and FLAIR sequences are superior to the MPRAGE sequence for evaluation of meningeal abnormalities and when used in combination have the maximum sensitivity for leptomeningeal abnormalities. The negative-predictive value is nearly 100%, where no leptomeningeal abnormality was detected on these sequences. Advances in knowledge: Post-contrast 3D-T1 -SPACE and 3D-T2 -FLAIR images are more useful than 3D-T1 -MPRAGE images in evaluation of meningeal abnormalities.