下咽頭梨状窩瘻の3症例

Three Cases of Piriform Sinus Fistula

I．はじめに

　下咽頭梨状窩痩は第3または第4鰓嚢に由来するとされる稀な先天性側頸瘻である。この瘻孔が感染経路となって急性化膿性甲状腺炎や頸部膿瘍が発生することが知られている^1〜3）。

　本稿では瘻管摘出術を行い病理組織学的に瘻管内腔に上皮組織を確認できた下咽頭梨状窩瘻の3症例について報告し，本症の診断・治療上の問題点について考察した。

　Piriform sinus fistula is a rare congenital anomaly and is known as a route of infection in acute suppurative thyroiditis. We presented 3 cases with this anomaly.

　A 58-year-old male developed lateral neck abscess which ruptured to the mesopharynx spontaneously several hours after admitting to our hospital. Barium swallowing studies revealed a fistula running from the apex of the left piriform sinus to the abscess. Histological examination of the fistula showed a tubular structure lined by squamous epithelium. Two other patients had recurrent acute suppurative thyroiditis resulting from infection through the piriform sinus fistula in the right side in one case, and the left in the other. The fistula was surgically removed in these cases. From our experiences, discussions were made on the genesis and the surgical methods of the removal of the fistula.