Type:
Educational Exhibit
Keywords:
Breast, Lymph nodes, CT, MR, Ultrasound, Biopsy, Cancer
Authors:
A. H. Brown, S. Shah, S. L. Dluzewski, B. Musaddaq, A. Malhotra
DOI:
10.26044/ecr2022/C-13240
Findings and procedure details
Ultrasound offers the most thorough assessment of the size and morphology of axillary lymph nodes due to its high soft-tissue resolution. Sonographic changes seen in COVID-19 vaccine related adenopathy include lymph node enlargement, a thickened cortex and loss of the normal fatty hilum (Figure 1).
Similarly, on CT the nodes may be enlarged with thickened cortices and possibly with surrounding fat stranding (Figure 2).
A feature unique to MRI in determining vaccination as the cause of axillary adenopathy is high T2/STIR signal in the ipsilateral deltoid muscle corresponding to the injection site.
Hypermetabolic axillary nodes may also be seen on fluoro-2-deoxy-d-glucose (FDG) PET/CT following COVID-19 vaccination. Again, an important finding that indicates the hypermetabolic lymph node is likely to be vaccine related is the synchronous finding of hypermetabolic inflammation in the ipsilateral deltoid muscle, corresponding to the site of injection (Figure 3).