This Turkish retrospective study looked at the success rates following endoscopic tympanoplasty using the double layer graft technique. This involves using a tragal cartilage and perichondrium composite graft and a separate perichondrial graft for closure of the perforation. The crescent cartilage-perichondrium composite graft is laid under the manubrium and bony annulus, and the perichondrium graft over the manubrium and under the remnant membrane.
A total of 155 patients were included in the study, with a significant improvement in hearing thresholds (p<0.05). The mean preoperative hearing threshold was 12.95+/-3.85dB and the mean postoperative threshold at 5.7+/-4.1dB. The average operation time was 30.2+/-5.2 minutes.
At one-year follow-up there was reperforation in 8.38% of cases, graft lateralisation in 5.80% of cases, and graft retraction in 2.58% of cases. The study suggests that using this double layer technique provides successful functional and hearing outcomes. The authors hypothesise that using the double layer technique provides mechanical stability whilst maintaining the elasticity of the graft.