There was only unkeratinized stratified epithelium or keratinized stratified squamous epithelium in the rectal end of the fistula or the urogenital fistula of low anorectal malformations, Those fistulas might be considered as an ectopic anal canal. 有瘘型肛门闭锁及低位肛门闭锁直肠远端或瘘管内覆未角化的复层上皮或角化的鳞状上皮,为正常肛管的异位。