액와-유방 접근법을 이용한 내시경 갑상선 절제술 후에 발생한 이물육아종의 초음파 소견

Abstract

Purpose: To assess the ultrasonographic (US) findings of foreign body granulomas detected by endoscopic thyroidectomy. Materials and Methods: On positron emission tomography-computed tomography of patients who had undergone endoscopic thyroidectomy, we encountered three fluorodeoxyglucose uptaken lesions in the surgical bed and those were pathologically confirmed to be foreign body granulomas. Additionally, 10 lesions demonstrating the same US findings were clinically diagnosed as foreign body granulomas. Echogenicity, shape, size, location, and vascularity were evaluated on US. Eleven lesions were subjected to follow-up US. Results: On US, seven lesions were found to be hyperechoic linear lesions with posterior acoustic shadowing while six other lesions were oval, iso- to slightly hypoechoic lesions. No vascularity was observed on color Doppler US. The size of the lesions was inversely correlated with the time to lesion detection (Spearman’s correlation r = -0.6528; p = 0.02). Oval iso- to slightly hypoechoic lesions (mean, 672 days) had statistically longer times from the time of thyroidectomy to lesion detection on US than hyperechoic linear lesions (mean, 318 days; Mann-Whitney test, p = 0.02). On follow-up US, the lesions had decreased in size and hyperechoic linear lesions became oval iso- to slightly hypoechoic lesions. Conclusion: In patients who underwent endoscopic thyroidectomy, characteristic US findings and evolutional changes are helpful for the diagnosis of foreign body granulomas and to distinguish from recurrent thyroid cancer, thus avoiding invasive procedures.