Objective To investigate the feasibility and application value of toluidine bule?dextran?40 (TB?Dex?40) as the tracer for lymphatic system in head and neck region. Methods Twenty healthy adult New Zealand white rabbits were equally divided into two groups: the experimental group (TB?Dex?40 group, n=10) and the control group (TB group, n=10). Rabbits in experimental group received submucosal injection of 1.0% (0.14 mOsm/L) TB?Dex?40, and the control group received injection of 1.0% (32.60 mOsm/L) TB. The staining time and fading time of lymphatic vessels and lymphnodes in the neck region were recorded, and the diffusion ranges of the two dyes in the tongue region were measured. Lymph nodespecimen were collected for pathological examination after 10 min, 1 hour and 4 weeks of staining. The experimental animals were sacrificed before and 4 weeks after the experiment. After death, organs of heart, lung, liver and kidney were examined pathologically. Results TB?Dex?40 reached sentinel lymph node (SLN) and stained lymphatic vessels at an average of (21.67±0.19) s after injection, while in control group was(3.22 ± 0.34) s (P<0.01). The time difference between the two dyes reaching sentinel lymph nodes was statistically significant. The durations from lymphatic staining to marked fading were (19.70 ± 1.34) min in experimental group and (14.30 ± 0.95) min in control group, respectively. The difference was statistically significant (P<0.01). SLN staining by TB?Dex?40 was still evident after 4 weeks, while TB staining has completely faded after 2 d.The average ranges of diffusionin tongue were (10.50±1.08) mm in experimental group and (20.00 ± 1.05) mm in controlgroup, respectively. The difference was statistically significant (P<0.01). No abnormalities were found in blood test and pathological examination of main organs. Conclusions TB?Dex?40 has high specificity forstaining lymphatic vessels and is a good tracer with potential clinical value.

Objective: To investigate the feasibility and application value of toluidine bule-dextran-40 (TB-Dex-40) as the tracer for lymphatic system in head and neck region. Methods: Twenty healthy adult New Zealand white rabbits were equally divided into two groups: the experimental group (TB-Dex-40 group, n=10) and the control group (TB group, n=10). Rabbits in experimental group received submucosal injection of 1.0% (0.14 mOsm/L) TB-Dex-40, and the control group received injection of 1.0% (32.60 mOsm/L) TB.The staining time and fading time of lymphatic vessels and lymphnodes in the neck region were recorded, and the diffusion ranges of the two dyes in the tongue region were measured. Lymph nodespecimen were collected for pathological examination after 10 min, 1 hour and 4 weeks of staining. The experimental animals were sacrificed before and 4 weeks after the experiment. After death, organs of heart, lung, liver and kidney were examined pathologically. Results: TB-Dex-40 reached sentinel lymph node (SLN) and stained lymphatic vessels at an average of (21.67±0.19) s after injection, while in control group was(3.22±0.34) s (P<0.01). The time difference between the two dyes reaching sentinel lymph nodes was statistically significant.The durations from lymphatic staining to marked fading were (19.70±1.34) min in experimental group and (14.30±0.95) min in control group, respectively.The difference was statistically significant (P<0.01). SLN staining by TB-Dex-40 was still evident after 4 weeks, while TB staining has completely faded after 2 d.The average ranges of diffusionin tongue were (10.50±1.08) mm in experimental group and (20.00±1.05) mm in controlgroup, respectively. The difference was statistically significant (P<0.01).No abnormalities were found in blood test and pathological examination of main organs. Conclusions TB-Dex-40 has high specificity forstaining lymphatic vessels and is a good tracer with potential clinical value.