Association of Dermal Hypoechogenicity and Cellulitis History in Patients with Lower Extremity Lymphedema: A Cross-Sectional Observational Study

Background: Recurrent cellulitis has high impact on physical, psychological, and social aspects for lymphedema patients. We speculated that identification of characteristics of skin and subcutaneous adipose tissue with cellulitis history can help considering new approach for prevention of recurrent cellulitis in lymphedema patients. Therefore, in this study, we aimed to noninvasively identify the ultrasonographic features of skin and subcutaneous tissue of lymphedema in patients with a cellulitis history. Methods and Results: This was a cross-sectional study, and all data were collected from patients' medical records. We assessed ultrasonographic images of the lower extremity of patients with lymphedema that were obtained in a lymphedema clinic. The ultrasonographic images were analyzed on the basis of the following five features: dermal hypoechogenicity, unclear dermal border, unclear superficial fascia, increased subcutaneous echogenicity, and subcutaneous cobblestone appearance. Fifty-two ultrasonographic images from 19 female patients with lower extremity lymphedema, including 8 with and 11 without a cellulitis history, were analyzed. The proportion of dermal hypoechogenicity on the upper leg was significantly higher in the patients with than in those without a cellulitis history (75.0% vs. 9.1%, p = 0.006). Conclusion: Cellulitis history in lymphedema patients appears to be associated with dermal hypoechogenicity, particularly in the proximal lower extremity. This finding suggests that it may be the initial step to consider new approach for prevention of recurrent cellulitis in lymphedema patients.