Indocyanine green-enhanced lymphography for upper extremity lymphedema: a novel severity staging system using dermal backflow patterns.

BACKGROUND: Management of arm lymphedema following breast cancer treatment is challenging, and emphasis should be put on early diagnosis and prevention of secondary lymphedema. Indocyanine green lymphography is becoming a method of choice for evaluation of lymphedema.
METHODS: Twenty patients with secondary arm lymphedema after breast cancer treatment underwent indocyanine green lymphography. Characteristic findings of indocyanine green lymphography were analyzed according to corresponding clinical stages and duration of edema. Based on changes in indocyanine green lymphography findings with progression of lymphedema, a new severity stage, arm dermal backflow stage, was developed and compared with clinical stages.
RESULTS: The indocyanine green lymphographic findings were classified into two large groups: linear pattern and dermal backflow patterns. The dermal backflow pattern could be subdivided into splash, stardust, and diffuse patterns. The dermal backflow patterns were found more frequently than the linear pattern in the proximal upper extremity (p=0.001). The dermal backflow patterns also increased significantly in prevalence overall as the duration of lymphedema increased (p=0.032). The arm dermal backflow stage was linearly correlated with clinical stage as described by the line y=1.092x+0.083 (R=0.997; analysis of variance, p<0.001).
CONCLUSIONS: Indocyanine green lymphography is a safe and convenient evaluation method for lymphedema that allows qualitative pathophysiologic assessment of lymphedema. The arm dermal backflow stage, based on indocyanine green lymphographic findings, is a simple severity staging system that demonstrates a significant correlation with clinical stage. Indocyanine green lymphography may come to play an important role in early diagnosis of secondary arm lymphedema. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, V.