Ultrasound-guided contrast-enhanced sentinel node biopsy of the head and neck in a porcine model

Abstract

To test the feasibility of contrast-enhanced ultrasound (CEUS)-guided sentinel lymph node biopsy (SNB) of the head and neck in a porcine model. In this prospective, nonrandomized study, methylene blue and Sonazoid were injected into the lateral tongue or floor of mouth (FOM) of four swine. Real-time CEUS was used to identify contrast in the lymphatic channels flowing to the sentinel lymph node (SLN). Endoscopic or open SNB was performed. Neck dissection was then performed, and the residual nodal packet was examined for remaining contrast-enhancing or blue dye-stained nodes. In all eight procedures, the SLN was visualized with ultrasound and blue dye. Seven procedures identified a single SLN, and one identified two SLNs. Subsequent neck dissections revealed no other nodes containing methylene blue or contrast in the nodal specimen or operative bed. CEUS-guided SNB of the head and neck in swine is feasible, with success comparable to blue dye-guided SNB. This technique may offer several advantages over traditional techniques, and warrants further study.