From the Department of Computational Diagnostic Radiology and Preventive Medicine (T.Y., T.N., S.K., N.H.) and Department of Radiology (S.M., O.A.), University of Tokyo Hospital, 7-3-1 Hongo, Bunkyo, Tokyo 113-8655, Japan.
Radiology. 2023 Jan;306(1):270-278. doi: 10.1148/radiol.220814. Epub 2022 Sep 13.
Background COVID-19 vaccination-related axillary lymphadenopathy has become an important problem in cancer imaging. Data are needed to update or support imaging guidelines for conducting appropriate follow-up. Purpose To investigate the prevalence, predisposing factors, and MRI characteristics of COVID-19 vaccination-related axillary lymphadenopathy. Materials and Methods Prospectively collected prevaccination and postvaccination chest MRI scans were secondarily analyzed. Participants who underwent two doses of either the Pfizer-BioNTech or Moderna COVID-19 vaccine and chest MRI from June to October 2021 were included. Enlarged axillary lymph nodes were identified on postvaccination MRI scans compared with prevaccination scans. The lymph node diameter, signal intensity with T2-weighted imaging, and apparent diffusion coefficient (ADC) of the largest enlarged lymph nodes were measured. These values were compared between prevaccination and postvaccination MRI by using the Wilcoxon signed-rank test. Results Overall, 433 participants (mean age, 65 years ± 11 [SD]; 300 men and 133 women) were included. The prevalence of axillary lymphadenopathy in participants 1-14 days after vaccination was 65% (30 of 46). Participants with lymphadenopathy were younger than those without lymphadenopathy ( < .001). Female sex and the Moderna vaccine were predisposing factors ( = .005 and = .003, respectively). Five or more enlarged lymph nodes were noted in 2% (eight of 433) of participants. Enlarged lymph nodes greater than or equal to 10 mm in the short axis were noted in 1% (four of 433) of participants. The median signal intensity relative to the muscle on T2-weighted images was 4.0; enlarged lymph nodes demonstrated a higher signal intensity ( = .002). The median ADC of enlarged lymph nodes after vaccination in 90 participants was 1.1 × 10 mm/sec (range, 0.6-2.0 × 10 mm/sec), thus ADC values remained normal. Conclusion Axillary lymphadenopathy after the second dose of the Pfizer-BioNTech or Moderna COVID-19 vaccines was frequent within 2 weeks after vaccination, was typically less than 10 mm in size, and had a normal apparent diffusion coefficient. © RSNA, 2022.
背景 COVID-19 疫苗接种相关腋窝淋巴结病已成为癌症成像中的一个重要问题。需要数据来更新或支持成像指南，以进行适当的随访。
目的 研究 COVID-19 疫苗接种相关腋窝淋巴结病的患病率、易患因素和 MRI 特征。
材料与方法 前瞻性收集了两次接种辉瑞-BioNTech 或 Moderna COVID-19 疫苗前后的胸部 MRI 扫描，并对其进行了二次分析。纳入了 2021 年 6 月至 10 月期间接受两次 Pfizer-BioNTech 或 Moderna COVID-19 疫苗接种并接受胸部 MRI 检查的患者。与接种前的 MRI 扫描相比，将接种后 MRI 扫描中发现的腋窝淋巴结肿大。测量最大增大淋巴结的淋巴结直径、T2 加权成像的信号强度和表观扩散系数（ADC）。通过使用 Wilcoxon 符号秩检验比较接种前后 MRI 的这些值。
结果 共有 433 名参与者（平均年龄 65 岁±11[标准差]；300 名男性和 133 名女性）入组。接种后 1-14 天，参与者腋窝淋巴结病的患病率为 65%（46 例中有 30 例）。有淋巴结病的参与者比没有淋巴结病的参与者年轻（ <.001）。女性和 Moderna 疫苗是易患因素（ =.005 和 =.003）。5 个或更多淋巴结肿大的参与者占 2%（433 名中有 8 名）。短轴大于或等于 10mm 的淋巴结肿大的参与者占 1%（433 名中有 4 名）。T2 加权图像上与肌肉相比的淋巴结信号强度中位数为 4.0；增大的淋巴结显示出更高的信号强度（ =.002）。在 90 名接受疫苗接种的参与者中，接种后增大淋巴结的 ADC 中位数为 1.1×10mm/sec（范围：0.6-2.0×10mm/sec），因此 ADC 值仍保持正常。
结论 在接种第二剂辉瑞-BioNTech 或 Moderna COVID-19 疫苗后的 2 周内，腋窝淋巴结炎在接种后 2 周内很常见，通常小于 10mm 大小，且 ADC 值正常。
© 2022 RSNA
