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The acronym FLAIR refers to fluid attenuation inversion recovery sequences, which are T2-weighted MR pulse sequences with liquor signal saturation by a long TI. They are characterized by long TR and TE and therefore the acquisition time is very long in the conventional mode, while fast imaging (the Turbo mode) reduces acquisition time to less than 2 minutes. Our study was aimed at codifying the use of this type of sequence in neuroradiologic studies. All the exams were performed with an MR unit with a 1-Tesla magnetic field. We carried out 150 neuroradiologic exams with this pulse sequence on patients with cerebral, medullary or orbital conditions. This technique is very useful to study periventricular or cortical lesions in multiple sclerosis and in other multifocal cerebral conditions (e.g., multiple metastases or lacunar infarcts), but we pointed out the following other advantages: better definition of the extent of infiltrative white matter lesions (i.e., gliomatosis cerebri and lymphomas), better differentiation of cystic from necrotic cavities and exact characterization of cortical damage in cerebral ischemic lesions (useful also for the differential diagnosis). Moreover, FLAIR pulse sequences could diagnose some globe conditions, such as amelanotic uveal melanomas and malformations with no need of contrast agent administration. In contrast, they were useless to study deep ischemic areas, solid neoplasms, hemorrhagic lesions, poroencephalic areas, intrinsic medullary lesions and intra-orbital and extra-ocular conditions. In conclusion, the FLAIR technique is a major diagnostic tool in neuroradiologic MR studies because they overcome such limitations of Turbo SE PD sequences as blurring artifacts; moreover, their acquisition time is always very short. In some cases, FLAIR images are decisive for the diagnosis.

In the last few years, new magnetic resonance (MR) pulse sequences called Fast or Turbo Spin Echo (TSE) sequences have become available. This kind of T2-weighted images is particularly useful for the study of spondylosis and degenerative spinal conditions, because it both reduces involuntary motion artifacts and its acquisition time is shorter than that of conventional SE T2-weighted images. Our study was aimed at assessing the diagnostic gain of this new type of pulse sequences in intrinsic spinal cord conditions. Therefore, we acquired TSE and conventional SE sequences, consequently, in 36 patients with intrinsic spinal cord conditions, which were apparent on T2-weighted images, and then compared the sensitivity, contrast resolution, and depiction of lesion margins and extent in both acquisition techniques. The results of our study follow: even though all lesions were identified with both techniques, contrast resolution was higher with TSE than with conventional SE images. Lesion margins and extent were substantially equally depicted with both techniques. Finally, TSE sequences had the same, and sometimes even higher, diagnostic yield than conventional SE sequences: therefore, TSE can be considered the sequence of choice in the study of intrinsic spinal cord conditions.