Background MRI is highly sensitive for assessing bone marrow involvement in multiple myeloma (MM) but does not enable detection of osteolysis. Purpose To assess the diagnostic accuracy, repeatability, and reproducibility of pseudo-CT MRI sequences (zero echo time [ZTE], gradient-echo black bone [BB]) in detecting osteolytic lesions in MM using whole-body CT as the reference standard. Materials and Methods In this prospective study, consecutive patients were enrolled in our academic hospital between June 2021 and December 2022. Inclusion criteria were newly diagnosed MM, monoclonal gammopathy of undetermined significance at high risk for MM, or suspicion of progressive MM. Participants underwent ZTE and BB sequences covering the lumbar spine, pelvis, and proximal femurs as part of 3-T whole-body MRI examinations, as well as clinically indicated fluorine 18 fluorodeoxyglucose PET/CT examination within 1 month that included optimized whole-body CT. Ten bone regions and two scores (categorical score = presence/absence of osteolytic lesion; semiquantitative score = osteolytic lesion count) were assessed by three radiologists (two experienced and one unfamiliar with pseudo-CT reading) on the ZTE, BB, and whole-body CT images. The accuracy, repeatability, and reproducibility of categorical scores (according to Gwet agreement coefficients AC1 and AC2) and differences in semiquantitative scores were assessed at the per-sequence, per-region, and per-patient levels. Results A total of 47 participants (mean age, 67 years ± 11 [SD]; 27 male) were included. In experienced readers, BB and ZTE had the same high accuracy (98%) in the per-patient analysis, while BB accuracy ranged 83%-100% and ZTE accuracy ranged 74%-94% in the per-region analysis. An increase of false-negative (FN) findings in the spine ranging from +17% up to +23%, according to the lumbar vertebra, was observed using ZTE (P < .013). Regardless of the region (except coxal bones), differences in the BB score minus the ZTE score were positively skewed (P < .021). Regardless of the sequence or region, repeatability was very good (AC1 ≥0.87 for all), while reproducibility was at least good (AC2 ≥0.63 for all). Conclusion Both MRI-based ZTE and BB pseudo-CT sequences of the lumbar spine, pelvis, and femurs demonstrated high diagnostic accuracy in detecting osteolytic lesions in MM. Compared with BB, the ZTE sequence yielded more FN findings in the spine. ClinicalTrials.gov Identifier: NCT05381077 Published under a CC BY 4.0 license. Supplemental material is available for this article.

中文翻译：

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基于 MRI 的零回声时间和黑骨假 CT 与全身 CT 相比检测多发性骨髓瘤的溶骨病变。


背景 MRI 对评估多发性骨髓瘤 （MM） 的骨髓受累高度敏感，但不能检测骨溶解。目的 以全身 CT 为参考标准，评估伪 CT MRI 序列 （零回声时间 [ZTE]、梯度回波黑骨 [BB]）检测 MM 溶骨病变的诊断准确性、可重复性和再现性。材料和方法 在这项前瞻性研究中，2021 年 6 月至 2022 年 12 月期间连续入组我们学术医院的患者。纳入标准是新诊断的 MM、意义未明且 MM 高危的单克隆丙种球蛋白病，或疑似进行性 MM。参与者接受了覆盖腰椎、骨盆和股骨近端的 ZTE 和 BB 序列，作为 3-T 全身 MRI 检查的一部分，以及 1 个月内有临床指征的氟 18 氟脱氧葡萄糖 PET/CT 检查，其中包括优化的全身 CT。10 个骨骼区域和 2 个评分（分类评分 = 存在/不存在溶骨性病变;半定量评分 = 溶骨病灶计数）由 3 名放射科医生 （2 名有经验，1 名不熟悉伪 CT 读数） 对 ZTE 、 BB 和全身 CT 图像进行评估。分类评分的准确性、可重复性和再现性（根据 Gwet 一致性系数 AC1 和 AC2）以及半定量评分的差异在每个序列、每个区域和每个患者水平进行评估。结果 共纳入 47 名参与者 （平均年龄 67 岁 ± 11 [SD];27 名男性）。在有经验的读者中，BB 和 ZTE 在每患者分析中具有相同的高准确率 （98%），而 BB 准确率在 83%-100% 之间，ZTE 准确率在每区域分析中在 74%-94% 之间。 根据腰椎，使用 ZTE 观察到脊柱假阴性 （FN） 结果的增加从 +17% 到 +23% 不等 （P < .013）。无论区域如何（髋骨除外），BB 评分减去 ZTE 评分的差异都是正偏态 （P < .021）。无论序列或区域如何，重复性都非常好（AC1 ≥0.87），而重现性至少很好（AC2 ≥0.63）。结论 基于 MRI 的腰椎、骨盆和股骨 ZTE 和 BB 伪 CT 序列在检测 MM 溶骨病变方面均表现出较高的诊断准确性。与 BB 相比，ZTE 序列在脊柱中产生了更多的 FN 发现。ClinicalTrials.gov 标识符： NCT05381077 在 CC BY 4.0 许可下发布。本文提供了补充材料。