Localization of the sentinel lymph node in tongue VX2 carcinoma via indirect CT lymphography combined with methylene blue dye injection.
CONCLUSIONS
Indirect computed tomography lymphography (CT-LG) combined with blue dye injection can locate the sentinel lymph node (SLN) in tongue carcinoma.


OBJECTIVE
To localize the SLN in tongue VX2 carcinoma using indirect CT-LG combined with methylene blue injection.


METHODS
Eighteen rabbits were placed into three groups: metastasis, hyperplasia, and control. Indirect CT-LG was performed with an iohexol injection into the tongue submucosa. CT images were acquired at 1, 5, and 15 min after injection. Methylene blue was injected into the same area 24 h after indirect CT-LG, followed by SLN identification and histopathological examination.


RESULTS
SLNs were visualized with an identification rate of 100%. SLN location identified using CT lymphography was confirmed by methylene blue dye. Control and hyperplastic enhanced SLNs were round or oval without any filling defects. Control rabbits had enhanced SLN attenuation values of 689.2 +/- 55.4 HU, 278.4 +/- 33.5 HU, and 71.7 +/- 9.2 HU at 1, 5, and 15 min after injection, respectively. Hyperplastic rabbits had values of 877.4 +/- 69.4 HU, 352.5 +/- 43.3 HU, and 80.2 +/- 11.5 HU. Filling defects were only observed in the ipsilateral metastatic SLNs of the metastasis group. CT attenuation values of the metastatic SLNs were 687.4 +/- 55.6 HU, 535.1 +/- 86.6 HU, and 282.3 +/- 19.4 HU at 1, 5, and 15 min, respectively, after iohexol injection. Metastatic lymph node attenuation values were significantly greater than those of the control or hyperplastic nodes at 5 (p < 0.001) and 15 min (p < 0.001) after injection.
Wu
Haitao
H
Department of Otolaryngology-Head and Neck Surgery, EENT Hospital, Fudan University, 83 FenYang Road, Shanghai, PR China. Haitaowu1103@hotmail.com
Ying
Haiyue
H
Xi
Xiuyian
X
Shen
Na
N
Shu
Yilai
Y
Hoffman
Matthew R
MR
Rieves
Adam
A
Sha
Yian
Y
Zhou
Liang
L
D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000473:pathology*; D004195:Disease Models, Animal; D004791:Enzyme Inhibitors / Q000008:administration & dosage; D007267:Injections; D008220:Lymphography / Q000295:instrumentation*; D008751:Methylene Blue / Q000008:administration & dosage; D011817:Rabbits; D021701:Sentinel Lymph Node Biopsy; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014062:Tongue Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*
D004791:Enzyme Inhibitors; D008751:Methylene Blue