The absence or closure of a normal body orifice or tubular passage such as the anus, intestine, or external ear canal.
The absence or closure of a normal body orifice or tubular passage such as the anus, intestine, or external ear canal.
（先天性）闭锁，无孔正常的身体孔或管道，如肛门、肠或外耳道的缺失或闭合