Comparison between modified Dixon MRI techniques, MR spectroscopic relaxometry, and different histologic quantification methods in the assessment of hepatic steatosis
Comparison between modified Dixon MRI techniques, MR spectroscopic relaxometry, and different histologic quantification methods in the assessment of hepatic steatosis
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DOI：
10.1007/s00330-015-3703-6
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发表时间：
2015-10-01
影响因子：
5.9
通讯作者：
Traeber, Frank
中科院分区：
文献类型：
--
作者：
Kukuk, Guido M.;Hittatiya, Kanishka;Traeber, Frank
为了系统地比较定量MRI、MR波谱（MRS）和不同的肝脏脂肪定量组织学方法，以确定可能的不一致性，在3 T MRI系统上对59例肝脏疾病患者进行了检查。使用改良狄克逊（m狄克逊）序列的双回波和六回波变体进行定量MRI，计算质子密度脂肪分数（PDFF）图，以及单体素MRS。组织学脂肪定量包括估计含有脂肪囊泡的肝细胞的百分比以及使用组织定量软件的半自动定量（qHisto）。在59名患者中的33名中，通过MRS测定，肝脂肪分数> 5%（最大45%，平均17%）。双回波mDixon产生的PDFF值系统性低于六回波mDixon（平均差异1.0%; P < 0.001）。六回波mDixon与MRS、qHisto和估计的含脂肪囊泡的肝细胞百分比具有良好的相关性（R分别为0.984、0.967、0.941，均P < 0.001）。与qHisto相比，通过含脂肪肝细胞的估计百分比获得的平均值高出2.5倍。六回波mDixon和MRS显示与qHisto获得的值的最佳一致性。六回波mDixon、MRS和qHisto提供最稳健和一致的结果，因此最适用于可靠的肝脏脂肪定量。六回波mDixon与MRS、qHisto和估计的含脂肪肝细胞百分比具有良好的相关性。六回波mDixon、MRS、qHisto和估计的含脂肪肝细胞百分比具有良好的相关性。和qHisto提供最稳健和一致的结果。双回波mDixon产生的PDFF值系统性低于六回波mDixon。含脂肪肝细胞的百分比为2.5-应考虑各种方法的性能特征和系统差异。
To compare systematically quantitative MRI, MR spectroscopy (MRS), and different histological methods for liver fat quantification in order to identify possible incongruities.Fifty-nine consecutive patients with liver disorders were examined on a 3 T MRI system. Quantitative MRI was performed using a dual- and a six-echo variant of the modified Dixon (mDixon) sequence, calculating proton density fat fraction (PDFF) maps, in addition to single-voxel MRS. Histological fat quantification included estimation of the percentage of hepatocytes containing fat vesicles as well as semi-automatic quantification (qHisto) using tissue quantification software.In 33 of 59 patients, the hepatic fat fraction was > 5 % as determined by MRS (maximum 45 %, mean 17 %). Dual-echo mDixon yielded systematically lower PDFF values than six-echo mDixon (mean difference 1.0 %; P < 0.001). Six-echo mDixon correlated excellently with MRS, qHisto, and the estimated percentage of hepatocytes containing fat vesicles (R = 0.984, 0.967, 0.941, respectively, all P < 0.001). Mean values obtained by the estimated percentage of hepatocytes containing fat were higher by a factor of 2.5 in comparison to qHisto. Six-echo mDixon and MRS showed the best agreement with values obtained by qHisto.Six-echo mDixon, MRS, and qHisto provide the most robust and congruent results and are therefore most appropriate for reliable quantification of liver fat.Six-echo mDixon correlates excellently with MRS, qHisto, and the estimated percentage of fat-containing hepatocytes.Six-echo mDixon, MRS, and qHisto provide the most robust and congruent results.Dual-echo mDixon yields systematically lower PDFF values than six-echo mDixon.The percentage of fat-containing hepatocytes is 2.5-fold higher than fat fraction determined by qHisto.Performance characteristics and systematic differences of the various methods should be considered.