The pre-chorda and post-chorda tympani approach in endoscopic stapes surgery based on the chorda tympani nerve classification

Endoscopic Cartilage Myringoplasty with Anterior Margin Preservation for Repairing Large Anterior Perforations

Objective: This study compared the graft outcomes and complications of endoscopic cartilage inlay myringoplasty with preservation of anterior margins (IPAM) and the cartilage underlay technique with raising the tympanomeatal flap (CUTF) for repairing large anterior perforations. Materials and Methods: In total, 55 patients with large anterior perforations were recruited and allocated to the IPAM (n = 28) or the CUTF (n = 27) group. The graft success rate, hearing gain, operation time, and postoperative complications were compared between the groups at 12 months. Results: The mean operation times were 29.3 ± 2.7 minutes and 46.4 ± 3.9 minutes in the IPAM and CUTF groups, respectively (P < .001). The residual perforation rate was 0.0% in the IPAM group and 11.1% in the CUTF group (P = .222). All patients completed the 12-month follow-up. The overall graft success rate was 96.4% in the IPAM group and 88.9% in the CUTF group (P = .577). No significant differences were observed between the groups in terms of postoperative pure-tone averages for air conduction and bone conduction, air-bone gaps (ABGs), or ABG changes. In the CUTF group, 22.2% of the patients reported altered taste perception, 3.7% experienced bony external auditory canal (EAC) stenosis, and 3.7% developed EAC cholesteatoma. By contrast, the IPAM group did not have any cases of altered taste perception, EAC stenosis, or cholesteatoma. Conclusions: Endoscopic cartilage myringoplasty with IPAM and anterior perichondrium folding is a simple, effective, and minimally invasive technique for repairing large anterior perforations. It offers a high graft success rate and better hearing improvement compared to CUTF.

Radiological Evaluation of Tympanic Segment of Chorda Tympani Nerve in Normal Ears: An Ultra-High-Resolution CT Study

BACKGROUND

To visualize the course of the tympanic segment of chorda tympani nerve (CTN) using ultra-high-resolution computed tomography (U-HRCT).

METHODS

A hundred and fourteen ears with no evident otologic pathologies were included. The tympanic segment of CTN was divided into four portions: periannular, posteromalleal, malleal, and anteromalleal. The length of the periannular portion running along the tympanic annulus was recorded. Four points of interest (the beginning and end of the posteromalleal and anteromalleal portions) were selected to perform distance measurements relative to the tip of the malleus manubrium. Differences in lengths and distances were compared in terms of ear sides and sexes.

RESULTS

The length of the periannular portion was 2.49 ± 1.16 mm. The beginning of the posteromalleal portion was located more laterally on the right side than on the left side (mean: 4.09 mm vs. 3.92 mm, P = 0.016). The end of the posteromalleal portion was located more inferiorly on the right (mean: 2.11 mm vs. 2.26 mm, P = 0.018). The beginning of the anteromalleal portion on the right was located more laterally than that on the left (mean: 2.60 mm vs. 2.45 mm, P = 0.027). The start and end of the anteromalleal portion were more posteriorly located in women than in men (both Ps < 0.001).

CONCLUSIONS

The course of the tympanic segment of normal CTN was comprehensively visualized by U-HRCT. Preoperative evaluation of the tympanic segment of CTN might be helpful in avoiding iatrogenic injury during middle ear surgery.