From the Department of Radiology, University of Bonn, Venusberg-Campus 1, 53127 Bonn, Germany.
Radiology. 2020 May;295(2):458-466. doi: 10.1148/radiol.2020191593. Epub 2020 Mar 24.
Background Abnormalities of the central lymphatic system (CLS) are increasingly treated by interventional radiology approaches. Planning of these procedures, however, is challenging because of the lack of clinical imaging tools. Purpose To evaluate the clinical usefulness of contrast agent-enhanced interstitial transpedal MR lymphangiography in the preinterventional workup of lymphatic interventions in patients with thoracic chylous effusions. Materials and Methods Patients with chylous effusions evaluated from January 2014 and December 2017 were included in this retrospective analysis of transpedal MR lymphangiography. Indications were chylothorax ( = 19; 76%), cervical lymphatic fistula ( = 2; 8%), and combined chylothorax and chylous ascites ( = 4; 16%). Patients underwent transpedal MR lymphangiography at 1.5 T with T1-weighted imaging after interstitial pedal of gadolinium-based contrast medium under local anesthesia. Contrast-enhanced MRI was evaluated for technical success, depiction of pathologic abnormalities of the CLS, and access site for lymphatic interventions (ie, clinically useful examination). Reader agreement for image quality and overall degree of visualization was assessed with weighted κ. Interrelations between overall image quality and degree of visualization of CLS structures were assessed by Spearman ρ. Efficacy of transpedal MR lymphangiography was calculated by using radiographic lymphangiography as the reference standard. Results Twenty-five patients (mean age, 54 years ± 18 [standard deviation]; 13 men) were evaluated. Eight percent (two of 25) of examinations failed (lymphoma in one patient and technical failure in one patient). Contrast agent injection was well tolerated without complications. Interrater agreement of image quality was excellent (κ = 0.96). The degree of CLS visualization correlated with overall image quality (ρ = 0.71; < .001). Retroperitoneal lymphatics, cisterna chyli, and thoracic duct were viewed with an accuracy of 23 of 25 (92%), 24 of 25 (96%), and 23 of 25 (92%), respectively. Anatomic variations, a lymphatic pathologic abnormality, and interventional access routes were identified with an accuracy of 22 of 25 (88%), 23 of 25 (92%), and 24 of 25 (96%), respectively. Overall, 23 of 25 (92%) transpedal MR lymphangiograms provided clinically useful information. Conclusion Transpedal interstitial MR lymphangiography was well tolerated by the patient and identified specific pathologic abnormalities causing thoracic chylous leakages before lymphatic intervention. © RSNA, 2020 See also the editorial by Maki and Itkin in this issue.
背景 中央淋巴系统（CLS）的异常情况越来越多地通过介入放射学方法进行治疗。然而，由于缺乏临床成像工具，这些程序的规划具有挑战性。目的 评估对比增强经皮足底 MR 淋巴造影术在胸淋巴漏患者淋巴介入术前评估中的临床应用价值。材料与方法 回顾性分析了 2014 年 1 月至 2017 年 12 月期间接受经皮足底 MR 淋巴造影术的患者。纳入标准为乳糜胸（ = 19；76%）、颈部淋巴瘘（ = 2；8%）和乳糜胸合并乳糜腹水（ = 4；16%）。所有患者均在 1.5 T 磁共振扫描仪下行经皮足底 MR 淋巴造影术，于局部麻醉下行足底间质注射钆类对比剂后行 T1 加权成像。评估对比增强 MRI 的技术成功率、CLS 病理异常的显示以及淋巴介入的入路（即临床有用的检查）。使用加权 κ 评估图像质量和 CLS 结构总体显示程度的读者间一致性。通过 Spearman ρ 评估整体图像质量与 CLS 结构显示程度之间的相互关系。以放射性淋巴造影术为参考标准计算经皮足底 MR 淋巴造影术的疗效。结果 25 例患者（平均年龄 54 岁±18 岁[标准差]；13 例男性）纳入研究。8%（2/25）的检查失败（1 例患者为淋巴瘤，1 例患者为技术失败）。对比剂注射耐受良好，无并发症。图像质量的观察者间一致性极好（κ = 0.96）。CLS 显示程度与整体图像质量相关（ρ = 0.71； <.001）。腹膜后淋巴管、胸导管和乳糜池的显示准确率分别为 25 例中的 23 例（92%）、25 例中的 24 例（96%）和 25 例中的 23 例（92%）。分别为 25 例中的 22 例（88%）、25 例中的 23 例（92%）和 25 例中的 24 例（96%）准确识别了解剖变异、淋巴病理异常和介入入路。总体而言，25 例中的 23 例（92%）经皮足底 MR 淋巴造影术提供了有临床意义的信息。结论 经皮足底间质 MR 淋巴造影术患者耐受性良好，可在淋巴介入术前识别导致胸淋巴漏的特定病理异常。
