巨大な偏在性甲状舌管嚢胞の1症例

A Large Laterally Located Thyroglossal Duct Cyst

I．はじめに

　甲状舌管嚢胞は胎生期の甲状舌管の遺残物であり^1），正中頸嚢胞という臨床診断名が示すとおり前頸部正中に存在する例が多い。耳鼻咽喉科の日常診療においてさほど稀な疾患ではないが，今回われわれが経験した症例は側頸部を中心としてきわめて大きな嚢胞を認めたものであり，特異な症例と考えられた。

　NMR-CT所見を含め文献的考察を加えて報告する。

　A 54-year-old female with a large thyroglossal duct cyst from the left submandibular area to the left oral floor was reported.

　It was located laterally in the neck and above the mylohyoid muscle, and had a string-like structure connecting itself to the base of the tongue. The cyst measured 85 × 55 × 47mm and weighed 137 gr. It contained very viscid fluid as had been expected from its T₁ and T₂ values (1,700 and 110, respectively) in the NMR-CT.