Methods The subcutaneous part of the external sphincter in the fissure and the internal sphincter under the dentate line were incised under direct vision in 250 patients.

• 方法对250例陈旧性肛裂患者采用裂口内直视下切断外括约肌皮下部和齿状线下部分内括约肌并修剪、切除病变组织。