PURPOSE To assess the ability and reproducibility of Non-contrast Magnetic Resonance Lymphography (NMRL) in detecting and quantify lymphedema, using a semiquantitative scoring system. METHODS AND MATERIAL This is a monocentric retrospective study of 134 consecutive patients with a clinical diagnosis of limb lymphedema who performed a Non-contrast Magnetic Resonance Lymphography (NMRL) at our Institution between November 2014 and February 2017. Lymphedema was classified based both on clinical and radiologic evaluation. An NMRL total score was obtained for each limb's segment and compared to the clinical grade, used as reference standard. NMRL intra-observer, inter-observer variability and intraclass correlation were calculated. NMRL sensitivity, specificity, and accuracy in identifying lymphedema were provided. Based on score distribution an NMRL four-stage system was developed. RESULTS NMRL showed 92% sensitivity, 77% specificity and 82% accuracy in identifying lymphedema. An almost perfect agreement was obtained by expert operators, while substantial agreement was obtained by non-expert operators. Substantial agreement resulted also for the inter-observer variability (Cohen's Kappa K = 0.73, CI 95% [0.69-0.78]). The intra-class correlation showed an almost perfect relationship both by expert and non-expert operators. Excellent correlation between clinical grade and NMRL score and between clinical grade and NMRL stage were found for each segment. CONCLUSIONS NMRL is a confident and reproducible exam with high sensitivity, good specificity and high accuracy in lymphedema detection; the semiquantitative NMRL score resulted a reliable and reproducible tool able to quantify lymphedema severity.

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关于使用非对比磁共振淋巴造影术（NMRL）的淋巴水肿半定量评分系统的建议：读者之间的可重复性以及与临床评分的相关性。

目的使用半定量评分系统评估非造影磁共振淋巴成像（NMRL）在检测和定量淋巴水肿中的能力和可重复性。方法和材料这是一项对2014年11月至2017年2月间在我院进行的134例临床诊断为肢体淋巴水肿的连续患者的单中心回顾性研究。该患者进行了非造影磁共振淋巴造影（NMRL）。放射学评估。获得每个肢体节段的NMRL总分，并将其与临床等级进行比较，用作参考标准。计算了NMRL观察者内部，观察者之间的变异性和类内相关性。提供了NMRL的敏感性，特异性和识别淋巴水肿的准确性。基于分数分布，开发了NMRL四阶段系统。结果NMRL在鉴别淋巴水肿方面显示出92％的敏感性，77％的特异性和82％的准确性。专家操作员获得了几乎完美的协议，非专家操作员获得了基本协议。观察者之间的差异也产生了实质性的一致性（Cohen Kappa K = 0.73，CI 95％[0.69-0.78]）。类别内的相关性显示，无论是专家还是非专家操作员，二者之间的关系都几乎完美。发现每个部分的临床等级与NMRL评分之间以及临床等级与NMRL分期之间具有极好的相关性。结论NMRL是一种自信且可重复的检查，在淋巴水肿检测中具有高灵敏度，良好的特异性和高精度。