Vascularized Lymph Node Transfer: A Primer for the Radiologist

Lymphedema, the accumulation of lymphatic fluid in the tissues, is a chronic disease and a major cause of long-term morbidity and disability. Lymphedema is usually a secondary condition, often caused by prior oncologic therapy, such as surgery for cancers, radiation therapy, and chemotherapy. Treatment for lymphedema has traditionally been conservative and limited, but new surgical and microsurgical procedures have arisen in recent years. Vascularized lymph node transfer (VLNT) is one of the most promising new microsurgeries. VLNT involves the transfer of functional lymph nodes (LNs) from a healthy donor site to an area of the body with damaged or diseased lymphatic drainage. The goal of the transplant is to restore physiologic LN drainage and improve lymphedema. Donor LNs are commonly found in the groin, axilla, neck, omentum, or submental region. Imaging can be used for preoperative planning to identify donor sites with the richest number of LNs. This can help identify those patients who may be candidates for VLNT and can help identify the best anatomic site for surgical harvest in those candidates. Imaging can be performed with US, CT, or MRI. VLNT preoperative imaging often requires acquisition techniques and reconstruction parameters that differ from those used in routine diagnostic imaging. Furthermore, to properly identify target LNs, the radiologist must be aware of surgical anatomic landmarks. (C) RSNA, 2020