Several surgical techniques have been documented for approaching and repairing superior semicircular canal dehiscence syndrome (SCDS). These techniques encompass the trans-middle cranial fossa, transmastoid, endoscopic approaches, and round window reinforcement (RWR). RWR entails the placement of connective tissue with or without cartilage and around the round window niche, restricting the round window\'s movement to minimize the 3rd window effect and restore the bony labyrinth closer to its normal state. We employed the multilayer RWR technique, resulting in significant postoperative improvement and long-lasting effects for 3.7 years in 2 cases. Here, we present the clinical findings, surgical procedures, and the effectiveness of multilayer RWR. This technique can be the initial choice for surgical treatments of SCDS due to its high effectiveness, longer-lasting effect, and minimal risk of surgical complications.

The aim of the present study is to report the outcomes of round window reinforcement surgery performed with the application of a Vibrant Soundbridge middle ear implant (VSB; MED-EL) in a patient with superior semicircular canal dehiscence (SSCD) who presented with recurrent vertigo, Tullio phenomenon, Hennebert\'s sign, bone conduction hypersensitivity, and bilateral moderate to severe mixed hearing loss. Vestibular evoked myogenic potentials (VEMPs) and high-resolution computed tomography (HRCT) confirmed bilateral superior semicircular canal dehiscence while this was not seen in magnetic resonance imaging. The surgical procedure was performed in the right ear as it had worse vestibular and auditory symptoms, a poorer hearing threshold, and greatly altered HRCT and VEMPs findings. With local-assisted anesthesia, round window reinforcement surgery (plugging) with perichondrium was performed with simultaneous positioning of a VSB on the round window niche. At the one and 3 months follow-up after surgery, VSB-aided hearing threshold in the right ear improved to mild, and loud sounds did not elicit either dizziness or pain in the patient.

Objectives were to describe the use of round window plugging for superior semicircular canal dehiscence syndrome and review further recommendations regarding the procedure based on our experience and to compare results with recent literature on round window plugging.
Retrospective case series.
Fourteen patients underwent round window plugging for superior semicircular canal dehiscence at our institution from 2012 to 2015. All patients underwent the same surgical procedure. Available pre- and postoperative data were reviewed.
Fourteen patient charts were reviewed. Symptoms of autophony improved in nine of 14 (64%) patients. Symptoms of pressure-induced vertigo improved in seven of 12 (58%) patients. Hennebert\'s sign that was positive preoperatively only improved in one of six (17%) patients. A positive preoperative vestibular evoked myogenic potential improved in only one of six (17%) patients. Six of 13 (46%) patients had increased air conduction thresholds postoperatively.
Round window plugging has been described as a less-invasive treatment for patients with superior semicircular canal dehiscence. Although the procedure did benefit some of our patients, successful outcomes were not predictable. Improvement in at least one objective finding was seen in only 21% of the patients studied. Hennebert\'s sign and vestibular evoked myogenic potentials that were positive preoperatively only improved in 17% of patients. At our institution, round window plugging is no longer considered a reasonable treatment option for most patients with superior semicircular canal dehiscence. We recommend that further study on this topic follow a standardized pre- and postoperative assessment.
4. Laryngoscope, 128:1445-1452, 2018.