rectal dilation

例句：

1. 1. He underwent a rectal dilation to relieve his constipation.
   他进行了直肠扩张以缓解便秘。
2. 2. During the procedure, the doctor performed a rectal dilation to remove the polyp.
   在手术过程中，医生进行了直肠扩张以移除息肉。
3. 3. The patient was admitted to the hospital for a rectal dilation due to severe constipation.
   由于严重的便秘，患者被收治入院接受直肠扩张治疗。