Endoscopic approach to the round window through posterior tympanotomy for cochlear implantation in children: A study on feasibility

Objective: To demonstrate the feasibility of rigid endoscopy through posterior tympanotomy, which provides both a view of the round window and direction of the scala tympani in children. Methods: After a standard mini-invasive surgical approach with postauricular access and transmastoid posterior tympanotomy of 2 mm, a 0°, 1.9 mm diameter and 11 cm long endoscope is positioned in proximity of the upper part of the posterior tympanotomy to obtain a panoramic view of the inferior part of the medial wall of the tympanic cavity. Surgical complications and changes in hearing threshold were analyzed. Results: Eight children were submitted to cochlear implantation with endoscopic assistance through posterior tympanotomy. Complete visualization of the round window niche was possible in every ear. No complications related to the procedure were observed. Preoperative threshold was preserved in 9 of 10 ears. Conclusions: Direct endoscopic view through the posterior tympanotomy allows visualization of the entire round window niche as well as the angle of introduction of the multi-electrode array along the direction of the scala tympani.