肛門部に発生したhuman tailの1例  [in Japanese] A Case of Perianal Human Tail  [in Japanese]

症例は11か月,男児.生下時より肛門部にpig tail様突起が認められていた.膀胱直腸障害,その他の神経学的症状は認められなかった.全身麻酔下に切除術を施行した.突起の中心部に外肛門括約筋に向かう索状物が認められ,これを切離した.切除標本に電気刺激を加えると収縮がみられ,更に刺激を継続すると次第に収縮が消失した.病理組織学的所見では,皮下の大部分が脂肪組織によって占められていたが,中心部には横紋筋の線維束が通っていた.術後の3D-CTで脊髄脂肪腫と,L_5-S_5の潜在性二分脊椎が認められたが,いわゆるtethered cord syndromeの所見は認められなかった.会陰・肛門部に発生する突起はhuman tailの1亜型と考えられているが,仙尾部に発生するものとは発生機序が異なることが推察された.

The patient was an 11-month-old baby boy, who had presented with a perianal process like a pig tail since birth. Neither vesicorectal disturbance nor any other neurological disorders were observed. He underwent resection of the protuberance under general endotracheal anesthesia. A fibromuscular band connecting to the external anal sphincter was transected. Though electrical stimulation resulted in the specimen's transient contraction, more stimulation did not. Histopathological findings revealed that the tail consisted of adipose tissue occupying most of the subcutaneous layer and a central striated muscular bundle. Postoperative three-dimensional CT revealed spinal lipomas and occult spina bifida between L_5 and S_5, but no findings of tethered cord syndrome. Though a process at perineal or perianal region could be considered as a kind of human tail, its genesis was considered different from that of sacrococcygeal origin.