MRI of non-specific low back pain and/or lumbar radiculopathy: do we need T1 when using a sagittal T2-weighted Dixon sequence?

Abstract

Objective To show that for the MRI workup of non-specific low back pain and/or lumbar radiculopathy, the acquisition of T1weighted sequences in the sagittal plane could be waived when using an FSE T2-weighted Dixon sequence. Materials and methods Three musculoskeletal radiologists retrospectively reviewed fifty lumbar spine MRI examinations performed for non-specific low back pain and/or lumbar radiculopathy. Two protocols were separately analyzed in the sagittal plane: a standard protocol (T1-weighted, in-phase, and water-only images of an FSE T2-weighted Dixon sequence) and a simplified protocol (fat-only, in-phase, and water-only images of an FSE T2-weighted Dixon sequence). Eight items usually assessed on T1-weighted sequences were analyzed for each of the vertebrae (n = 250), vertebral endplates (n = 500), vertebral corners (n = 1000), foramina (n = 500), lamina (n = 500), and facet joints (n = 500). Interchangeability of these protocols was tested using the individual equivalence index. A decrease in interobserver agreement of ≥ 5% when one reader used the simplified protocol compared with when both readers used the standard protocol was considered clinically significant. Interreader and intrareader agreement were assessed using kappa statistics. Rates of findings with each protocol were compared using odd ratios. Results The standard and simplified protocols were interchangeable (range of upper bound of the 95%CI of individual equivalence index = 0.25 to 1.38%). Intraprotocol and interprotocol interreader kappa values were similar (0.253-0.671 vs. 0.236-0.723, respectively). Rates of findings were not statistically significantly different (p ≥ 0.074), or were higher with the simplified protocol (p ≤ 0.036). Conclusion In our target population, a single sagittal T2-weighted Dixon sequence may replace the recommended combination of T1-, T2-, and fat-suppressed T2-weighted sequences. Key Points • In patients with non-specific low back pain or lumbar radiculopathy, spine MRI in the sagittal plane could be limited to a single FSE T2-weighted Dixon sequence, hereby reducing the acquisition time. • A simplified protocol of spine MRI in the sagittal plane combining FSE T2-weighted Dixon sequence provides the same information as a standard protocol including T1-, T2-, and fat-suppressed T2-weighted sequences for the workup of degenerative lumbar spine lesions. • For some findings shown on the simplified protocol, such as focal bone marrow replacement lesions or signs of infection, additional sequences including pre-and post-contrast T1-weighted sequences may be required, as is currently the case when using the standard protocol.

Resveratrol‐enhanced SIRT1‐mediated osteogenesis in porous endplates attenuates low back pain and anxiety behaviors

“…The endplates are vulnerable to suffered from lesions, and termed as the “weak link” of the lumbar spine 8‐10 . Endplates lesions cause considerable reduction in the disk’s proteoglycan and lead to elevated catabolic enzymes and pro‐inflammatory cytokines, resulting in degenerative changes 37,38 .…”

Differentiation between benign and malignant vertebral compression fractures using qualitative and quantitative analysis of a single fast spin echo T2-weighted Dixon sequence

“…In particular, a recent meta-analysis of eighteen studies on this topic found a pooled sensitivity, specificity, and AUC of 89% (95% CI: 86, 92%), 88% (95% CI: 85, 91%), and 0.95, respectively [4]. In light of these results, a single FSE T2w Dixon sequence could be used instead of the set of sequences which are usually acquired in the sagittal plane for this indication, as has been previously shown for spine MRI protocols for the detection of metastases or for the workup of non-specific low back pain or lumbar radiculopathy [11,12]. Using a single sagittal FSE Two-by-two differences: no statistical difference between readers (all p > 0.29, Bonferroni corrected significance level p < 0.008) AUC, area under the curve; 95% CI, 95% confidence intervals; +LR, positive likelihood ratio; −LR, negative likelihood ratio; NA, not applicable.…”

“…The image sets derived from a T2w Dixon acquisition include in-phase, out-of-phase, fat-only, and water-only. The derived fat-only images offer an additional benefit: they may replace T1-weighted sequences for the study of bone marrow fat in some indications [11,12]. This has allowed the simplification of protocols for several applications, including the detection of bone marrow metastases, sacroiliitis, or for the workup of low back pain and/or lumbar radiculopathy [11][12][13].…”

“…The derived fat-only images offer an additional benefit: they may replace T1-weighted sequences for the study of bone marrow fat in some indications [11,12]. This has allowed the simplification of protocols for several applications, including the detection of bone marrow metastases, sacroiliitis, or for the workup of low back pain and/or lumbar radiculopathy [11][12][13]. However, the diagnostic performance of the morphological assessment of a simplified protocol using a single FSE T2w Dixon sequence in the differentiation between benign and malignant VCFs has not yet been assessed.…”

Implementation of a sagittal T2-weighted DIXON turbo spin-echo sequence may shorten MRI acquisitions in the emergency setting of suspected spinal bleeding

“…In a study among patients showing various types of vertebral lesions (including recent fractures, spondylitis, metastasis, and haemangioma), a T2-weighted DIXON sequence showed more homogeneous fat suppression and superior lesion conspicuity when compared to imaging using spectral attenuated inversion recovery (SPAIR) [ 17 ]. For the degenerative lumbar spine, previous studies were able to demonstrate that imaging with a single sagittal T2-weighted DIXON sequence could replace the combination of dedicated T1-weighted, T2-weighted, and STIR sequences, which would not be at the expense of worsened diagnostic performance [ 18 , 19 ].…”