Application of ultrasound-guided pre-operative injection of carbon nanoparticles in endoscopic radical thyroidectomy

Background: Central lymph node dissection is crucial in endoscopic radical thyroidectomy. We aim to introduce a method of preoperative ultrasound-guided injection of carbon nanoparticles. Methods: We reviewed the medical records of 89 patients who underwent surgery between March 2020 and March 2023. Clinical and pathological data of the patients were analyzed, and postoperative outpatient follow-up was conducted. Results: A total of 89 patients were included: 79 female, 10 male. Surgical procedures: radical thyroidectomy, 13 cases via oral, 76 cases via submental combined oral; operation time: 156 ± 29 minutes, postoperative hospital stay: 3.3 ± 0.6 days. 2 cases of bilateral carcinoma (2.2%), 87 cases of unilateral carcinoma (97.8%): single lesion 76 cases (87.4%), double lesions 10 cases (11.5%), 3 lesions 1case (1.1%); the maximum diameter: 7.9 ± 5.0 mm, 74 cases (83.1%) ≤ 10 mm; LNM: Nx 3 cases (3.4%), N0 42 cases (47.2%), N1a 44 cases (49.4%). The total number of lymph node dissection: 7.0 ± 3.7, 65 cases ≥ 5 (73.9%), N1a 1.5 ± 1.9. After 1 month of outpatient follow-up, there was no cough due to drinking water, hoarseness, numbness of hands and feet. Conclusions: Preoperative ultrasound-guided injection of carbon nanoparticles is simple and convenient, increasing the number of lymph node dissection, and increasing the positive rate of lymph nodes. In addition, there is no need to add additional operational steps during the operation, making the operation smoother and improving surgical efficiency. Therefore, it has certain clinical application value in preoperative preparation for endoscopic thyroidectomy.