Interlayer repair with porcine small intestinal submucosa versus internal repair with tragus cartilage in endoscopic tympanoplasty

Objective

Endoscopic tympanoplasty includes various surgical methods, such as internal repair, interlayer repair, and external overlay. This technique requires autologous materials, allografts, and xenografts, which are used to repair tympanic membrane (TM) perforation. To obtain good results, appropriate surgical methods and repair materials should be selected. This study aims to assess the efficacy of repairing refractory TM perforations in the porcine small intestinal submucosa (SIS) during transcanal endoscopic type I tympanoplasty.

Method

A retrospective chart review was performed on patients who underwent TM perforation repair with porcine SIS and tragus cartilage between January 2022 and September 2022 at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine. Perforation size, tympanic status, pre- and postoperative symptoms, follow-up data, wound healing rates, and hearing improvement were analysed.

Results

Of the 115 patients included in the study, 56 underwent interlayer repair with porcine SIS of the TM, and 59 patients underwent internal repair with tragus cartilage. No significant difference was found between the two groups at baseline in terms of age, sex, disease course, perforation side, tympanic status, underlying disease, or preoperative infection. The total postoperative effective rate of interlayer implantation with porcine SIS was 91.07% (51 patients), and that of internal implantation with tragus cartilage was 88.14% (52 patients). No significant difference was found in terms of the graft success rate between the two surgical methods (p = 0.887). Postoperative pure tone auditory (PTA) and air-bone gap (ABG) density significantly increased in both groups compared with before surgery (p < 0.05). However, the postoperative PTA and ABG density were not significantly different 3 months post-surgery between the two groups (p > 0.05). Compared to those in the internal implantation group, the patients in the interlayer group had a shorter operation duration (51.36 ± 6.76 min vs. 59.71 ± 7.45 min, t = 6.298, p < 0.001) and less blood loss (11.91 ± 2.61 mL vs. 15.27 ± 2.57 mL, t = 7.019, p < 0.001).

Conclusions

Our study suggests that the porcine SIS, as well as the tragus cartilage, has a high success rate in repairing irreversible TM perforation. Endoscopic tympanoplasty via interlayer implantation with porcine SIS offers distinct advantages, including the absence of donor-site incision and scar formation, and ease of graft modification and manipulation.