A study of intracochlear trauma after insertion of cochlear implant electrode arrays through the round window in temporal bone specimens

• Grant number: 11/20095-0
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2012
• End date: February 28, 2014
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Ricardo Ferreira Bento
• Grantee: Ricardo Ferreira Bento
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The cochlear implantation is a well-established treatment for severe, profound bilateral hearing loss. The technological advancement of cochlear implants and the good results obtained with their use have encouraged a broadening of selection criteria. Consequently, there is now a growing number of cochlear implantation candidates with significant residual hearing, particularly in the low frequencies, and a great concern about the atraumatic insertion of the cochlear implant to preserve residual hearing.Previous studies have indentified that the likelihood of trauma to intracochlear structures during the surgery is lower when cochleostomy, for the insertion of the electrode array, is performed inferior instead of anterior to the round window, making hearing preservation more likely. However, this approach requires further dissection of the facial recess region; the facial nerve and chorda tympani nerve must be completely skeletonized. The need for this procedure would certainly discourage many surgeons for performing these cochleostomy. Another approach for the insertion the electrode array is through the round window. Unlike cochleostomy, this access does not require drilling for opening the cochlea, which minimizes the intracochlear trauma. However, there are not studies that compare if the intracochlear trauma is different when the electrode is inserted through different quadrants of the round window.The objective of this study is to assess whether there is a difference in intracochlear trauma when the electrode array is inserted through the anterior or posterior portion of the round window, and develop conditions for new temporal bone studies to be performed in our service. (AU)