Comparison of turbo spin echo and HASTE pulse sequence in brain MRI

The purpose of this study was to evaluate the utility of Half-Fourier Acquisition Single Shot Turbo Spin Echo (HASTE) imaging of the brain, and to compare the results with those of the Turbo Spin Echo (TSE) technique. TSE and HASTE sequences were retrospectively compared in 31 patients (19 men and 12 women) with cerebral lesions seen on TSE MR images. The related diagnoses were neoplasm(n=3D4), hematoma(n=3D5), cerebromalacia(n=3D4), infarct or ischemia(n=3D17), and granuloma(n=3D1). Qualitative analysis involved the independent reviesw by two radiologists of TSE and HASTE images with regard to overall image quality, conspicuity of the lesion, delineation of the gray-white matter, conspicuity of the basal ganglia, degree of flow and ghost artifacts. All parameters were graded 1-4(1=3Dpoor, 4=3Dexcellent), and for quantitative analysis, lesion-white matter, gray-white matter, and putamen-white matter contrast to noise ratios (CNR) were measured. During qualitative analysis, all lesions seen on a TSE image were detrected on the corre-sponding HASTE image, but with regard to overall image quality, conspicuity of the lesion, delin-eation of gray-white matter, and conspicuity of the basal ganglia, HASTE imaging was inferior to that of TSE;on TSE, these parameters were scored 4.0, 4.0, 3.7, and 3.7 respectively, and on HASTE, the corresponding figures were 2.9, 3.0, 1.5, and 1.9(p<0.05). For ghost and flow artifacts, no significant differences were demonstrated (p>0.05). Quantitative assessment showed that lesion-white matter CNR was not significantly different between the two techniques(p>0.05). Gray-white matter and putamen-white matter CNRs were 100.4±81.8 and 92.6±84.6 on TSE, and 45.8±39.2 and 42.7±40.6 on HASTE, respectively(p<0.05). With regard to image quality, delineation of lesion and anatomic details, HASTE imaging is inferior to that of TSE, and this indicates that for routine brain imaging, HASTE cannot replace TSE. In view of its fast acquisition time, however, HASTE might sometimes be a useful alternative to TSE.=20