Feasibility and agreement of stiffness measurements using gradient-echo and spin-echo MR elastography sequences in unselected patients undergoing liver MRI

Abstract

In clinical setting, there is a high correlation between the GRE and SE MRE stiffness measurements, independently of the degree of liver fat infiltration measured by PDFF. A strong correlation between SE-MRE sequences is found even in patients with iron overload. Advances in knowledge: Our study addresses liver iron and fat content simultaneously to describing the technical feasibility and correlation between different MRE sequences in consecutive unselected patients refereed for liver MRI. EPI SE-MRE should be considered an optimal alternative to assess liver fibrosis in patients in whom GRE-MRE failures, such as iron-overloaded, in pediatric, elderly, or severely ill populations.

Comparison of technical failure of MR elastography for measuring liver stiffness between gradient‐recalled echo and spin‐echo echo‐planar imaging: A systematic review and meta‐analysis

“…Finally, 31 studies fulfilled the eligibility criteria for our analysis, including eight studies using both GRE and SE‐EPI sequences, 22 studies using only a GRE sequence, , , , , , , , and one study using only an SE‐EPI sequence . As one study using both GRE and SE‐EPI sequences potentially overlapped with a population in another GRE sequence outcome study, we did not include the outcomes of this study in the evaluation of the pooled proportion of technical failure of GRE sequences, but used it only for the head‐to‐head comparison between GRE and SE‐EPI sequences.…”

“…The demographic characteristics of the included studies are shown in Table . In brief, subjects were enrolled prospectively in 16 studies and retrospectively in 15 studies , , , , , , , . The mean patient ages in 14 studies , , , , , , , , ranged from 25 to 60.5 years, but we could not analyze patient age in the other studies, because they did not report demographic information on all subjects, but reported only those with successful examinations.…”

“…Eight studies compared the proportions of technical failures between GRE and SE‐EPI sequences using the same subjects . As two eligible studies also performed MRE using both 1D‐ and 3D‐MEG, we used the outcomes with 1D‐MEG, given that all the GRE studies were performed with 1D‐MEG.…”

“…Under GRE, this long TE makes the sequence heavily T 2 *‐weighted, resulting in considerable signal dephasing in tissues with short transverse relaxation times such as iron‐overloaded liver. By contrast, the spin‐echo‐based pulse sequence is intrinsically less T 2 *‐dependent because of the presence of the 180° refocusing pulse . Some studies with a GRE sequence suggested that iron deposition was the major cause of technical failure in GRE‐based MRE studies, whereas only a few studies using an SE‐EPI sequence indicated it as a potential cause of failed examinations.…”

“…Nonetheless, as people tend to focus more on successful results rather than technical failure when presenting the results of studies, the failure rates of MRE have not been reported well. A limited number of studies have reported on the technical failure rate of MRE, and fewer studies have made comparisons regarding the failure rates between these two sequences. The results from the studies are also limited by their small sample sizes and the resulting low levels of evidence.…”