Efficacy of complete decongestive therapy (CDT) on edematous rat limb after lymphadenectomy demonstrated by real time lymphatic fluid tracing

Abstract

Purpose Although complete decongestive therapy (CDT) is considered to reduce the volume of lymphedema, there is no concrete evidence to sustain its efficacy. The purpose of the present study was to find new evidence of CDT based on visualizing the changes of lymph fluid accumulating in an edematous limb using indocyanine green (ICG) fluorescent lymphography in real time. Methods Twelve lymphedema rats were divided randomly into two groups. On the first day, ICG was injected into an edematous limb of rats, and no-intervention and CDT was applied to groups 1 and 2, respectively, for two weeks. ICG lymphography and circumferential measurements were done every two days in each two-week observation. Results A fluorescent flow to the ipsilateral axillary fossa was identified in all rats. In addition, network-like and dermal backflow patterns were observed in the lower legs and thighs. While manual lymph drainage was applied in the CDT group, the flow moved more rapidly through this pathway than that in the no-intervention group. An area of high-intensity fluorescent signals concentrated around the injection sites diminished in the CDT group more than that in the no-intervention-group after two weeks. Circumferential lengths of the edematous limbs were longer than the non-edematous limbs in both groups 1 and 2 on the day of ICG injection. The no-intervention group 1 showed no significance differences during 14 days, whereas the CDT group 2 exhibited very significant differences. Conclusion These results suggest that CDT has beneficial effects in lymphedema treatment.