先天性肛门直肠畸形鼠仔的病理特点

摘要

Anorectal malformations were induced in the fetuses of rats by administrating ETU.The pathological changes were observed.The results showed that the fetuses with low anorectal malformation had normal internal sphincter.But the internal sphincter was smaller in anterior rectal wall in high and intermediate anorectal malformations.The lower the rectal blind pouch situated,the larger area the internal sphincter occupied.There was no real internal sphincter in the fetuses with high and intermediate anorectal malformations.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.The external sphincter might be abseent,ectopic,or normal,while the levator ani muscle was weaker in all fetuses with anorectal deformities.The fistulous commencement and the rectal blind pouch should be preserved and utilized as much a possible in anoplastic operations.%为了解先天性肛门直肠畸形的病理改变,用乙烯硫脲(ETU)诱发大白鼠产生肛门闭锁畸形鼠仔,观察其盆腔病理改变.结果:低位肛门闭锁肛门内括约肌正常;高、中位有瘘型肛门闭锁存在内括约肌,但直肠前壁短小,畸形位置越低,内括约肌面积越大;高、中位无瘘型肛门闭锁无内括约肌.有瘘型肛门闭锁及低位肛门闭j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.肛门闭锁畸形鼠仔外括约肌缺如、异位或正常.肛提肌薄弱.肛门闭锁畸形术中应充分保留瘘管近端及直肠盲端组织.