Half-fourier acquisition single-shot turbo spin-echo (HASTE) MR: comparison with fast spin-echo MR in diseases of the brain

To compare an ultrafast T2-weighted (half-Fourier acquisition single-shot turbo spin-echo [HASTE]) pulse sequence with fast spin-echo T2-weighted sequences in MR imaging of brain lesions. Fast spin-echo and HASTE images of 34 consecutive patients over the age of 50 years or with suspected demyelinating disease were reviewed independently by two neuroradiologists for the number of lesions less than 5 mm and greater than or equal to 5 mm, and for lesion conspicuity, gray-white matter differentiation, and extent of periventricular confluent signal abnormality. The reviewers also assessed for the presence of hemosiderin and extent of motion artifacts. Per patient, the mean number of 5-mm or larger lesions detected on fast spin-echo images (1.4) relative to the number detected on HASTE images (0.8) was not statistically significant. For lesions less than 5 mm, fast spin-echo images showed more lesions (7.5) than HASTE images did (2.4). The fast spin-echo images were better at depicting gray-white matter differentiation, conspicuity of lesions, and periventricular signal abnormality. Of four T2 hypointense lesions seen on fast spin-echo images, none was detected on HASTE images. Although the HASTE technique might be useful for rapid imaging of the brain, our study shows a diminished sensitivity for the detection of lesions less than 5 mm in diameter and for T2 hypointense lesions.