Comparison of Single-Echo T2-weighted Fast Spin-Echo and Conventional Spin-Echo MR Sequences

Abstract

We compared single-echo T2-weighted fast spin-echo (FSE) magnetic resonance imaging and conventional spin-echo (CSE) T2-weighted imaging in the detection of brain lesions of multiple sclerosis (MS). 16 patients with clinically definite MS underwent brain imaging at 0.5 T with T2-weighted single-echo fast spin-echo (FSE) and conventional spin-echo (CSE) sequences. Image analysis was performed by three of the investigators who worked together to reduce interobserver variability. Statistical analysis was performed using Student's t test to assess the difference in the contrast-to-noise (C/N) ratio of MS lesions between CSE and FSE sequences. The Wilcoxon signed rank test was used to evaluate the difference in the number of lesions between the two sequences. There was no significant difference in the overall total number of lesions detected on FSE vs CSE (964 vs 1009, P >.05). However significantly (P = .02) more posterior fossa lesions were detected using FSE than CSE, whereas significantly (P = .002) more periventricular lesions were detected using CSE than FSE. The difference in the number of lesions in the other sites was not significant (P > .05). There was no significant difference in the overall total C/N ratio of MS lesions between FSE and CSE sequences (11.7 ± 3.9 vs 12.6 ± 4). Considerable time savings can be made when substituting FSE for CSE sequences in T2-weighted imaging, and this is a compelling reason to employ such sequences in clinical practice. Our results suggest that for single-echo T2-weighted imaging, FSE can replace CSE in long term monitoring especially when patient movement prevents a useful investigation and when optional scanning planes are required.