© Copyright JLO (1984) Limited 2016Â.Background: Subtotal petrosectomy combined with cochlear implantation is a procedure required in specific situations. Methods: A retrospective review of all cases of subtotal petrosectomy in cochlear implant surgery over a five-year period was performed. The indications, complications and outcomes for this procedure are outlined. Results: Sixteen patients underwent cochlear implantation in combination with subtotal petrosectomy and blind sac closure of the external auditory meatus from 2008 to 2013. Seventy-five per cent of these were completed as a two-stage procedure and 25 per cent as a single-stage procedure. The most common indications for the procedure were chronic otitis media, previous radical cavity, and for surgical access in challenging anatomy or in drill-out procedures. Mastoids were obliterated with fat or musculoperiosteal flaps. The complication rate relating to blind sac closure was 6 per cent. Cochlear implants were successfully placed in all cases and there was no incidence of device failure. Conclusion: For patients with chronic suppurative otitis media or existing mastoid cavities, subtotal petrosectomy with blind sac closure of the external auditory canal, closure of the eustachian tube, and cavity obliteration is an effective technique to facilitate safe cochlear implantation.