Comparison of T1-weighted fast spin-echo and T1-weighted fluid-attenuated inversion recovery images of the lumbar spine at 3.0 Tesla

Purpose: To compare T1-weighted FSE and fast T1-weighted FLAIR imaging in normal anatomic structures and degenerative and metastatic lesions of the lumbar spine at 3.0T. Material and Methods: Thirty-two consecutive patients (19 females, 13 males; mean age 44 years, range 30-67 years) with lesions of the lumbar spine were prospectively evaluated. Sagittal images of the lumbar spine were obtained using T1-weighted FSE and fast T1-weighted FLAIR sequences. Both qualitative and quantitative analyses measuring the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and relative contrast (ReCon) between degenerative and metastatic lesions and normal anatomic structures were conducted, comparing these sequences. Results: On quantitative evaluation, SNRs of cerebrospinal fluid (CSF), nerve root, and fat around the root of fast T1-weighted FLAIR imaging were significantly lower than those of T1-weighted FSE images (P < 0.001). CNRs of normal spinal cord/CSF and disc herniation/ CSF for fast T1-weighted FLAIR images were significantly higher than those for T1-weighted FSE images (P < 0.001). ReCon of normal spinal cord/CSF, disc herniation/CSF, and vertebral lesions/CSF for fast T1-weighted FLAIR images were significantly higher than those for T1-weighted FSE images (P < 0.001). On qualitative evaluation, it was found that CSF nulling and contrast at the spinal cord (cauda equina)/CSF interface for T1-weighted FLAIR images were significantly superior compared to those for T1-weighted FSE images (P < 0.001), and the disc/spinal cord (cauda equina) interface was better for T1-weighted FLAIR images (P < 0.05). Conclusion: The T1-weighted FLAIR sequence may be considered as the preferred lumbar spine imaging sequence compared to T1-weighted FSE, as it has demonstrated superior CSF nulling, better conspicuousness of normal anatomic structures and degenerative and metastatic lesions, and improved image contrast.