下咽頭梨状窩瘻の2例

Two Cases of Piriform Sinus Fistula

　はじめに

　急性化膿性甲状腺炎の原因の1つとして先天奇形の下咽頭梨状窩瘻が考えられている。下咽頭梨状窩瘻の発生は第3,4,5咽頭嚢の遺残物とする説^1,2）がある。また最近，甲状腺C細胞過形成が認められることから第5咽頭嚢由来説が唱えられてきた^3）。今回われわれは2例（成人1例と小児1例）の自験例で，摘出した梨状窩瘻に免疫組織学的手法を用いて，甲状腺C細胞との関連に関して検討を行ったので報告する。

A 41-year-old and a 10-year-old male presented with piriform sinus fistula. The diagonsis was made by pharyngeal enhancement radiograpy in bothcases. Pyoktanin blue dying was used during direct layngoscope. Partial thyroidectomy and fis-tulectomy were done. Anti-calcitonin stains were negative near fistula but were positive in other parts. Therefore, we could not assume from these findings that fistulas were from fifth pharyngeal pouch. Retrospectively we failed to identifiy the distal end of fistula during operative procedure. No recurrence was observed after surgery in each case.