The objective of this study was to evaluate the transport of radiotracers in lymphatic collectors during manual lymphatic therapy. The legs of four male and two female patients with leg lymphedema were assessed using lymphoscintigraphy before, during and after manual lymphatic therapy. The ages of the patients, treated in Hospital de Base in Sao Jose do Rio Preto, ranged from 42 to 64 years with a mean age of 51.2 years. Consecutive patients with grade II leg lymphedema were enrolled in this study. Patients with lymphedema secondary to lymphadenectomy, active infections and weight greater than 130 kg were excluded. Patients were submitted to manual lymphatic therapy, which consists of the collapsing of capillaries using manual compression which is then slid along the skin in a stroking action in the direction of the lymph flow within lymphatic vessels towards the lymph nodes. Two dynamic studies were performed; the first was over 40 minutes (3 images every 10 minutes) which was immediately followed by an entire body scan. A second dynamic evaluation was performed taking images at 10-second intervals over 2 minutes during manual lymphatic therapy. To evaluate the displacement of radiotracers, the path of lymphatic collectors from the knee to a lymph node in the upper thigh was divided into five similarly sized regions of interest. The concentration of radiotracer was quantified in each of the regions of interest. The paired t-test was used for statistical analysis with an alpha error of 5% (p value < 0.05) being considered statistically relevant. The results show statistically significant differences in the number of particles in all the regions of interest comparing before and after treatment (two-tail paired t-test: p value < 0.0001). Manual lymphatic therapy improves the transport of radiotracers in lymphatic collectors.