After following up from 6 months to 14 years,the hearing level was increased over 15 dB in 426 ears(80 7%). Histological observation was taken for cartilage column which was (80 7%).

• 528 耳术后经6 个月至14 年随访， 听力提高15dB以上的有426 耳， 占80－7%25 。