Effective closure of a large postauricular fistula using a cervico-occipital flap in a patient after cochlear implantation with the subtotal petrosectomy technique – A case report

Background Postauricular fistulas represent a rare but challenging complication of cochlear implant surgery, particularly following the subtotal petrosectomy approach. Primary closure attempts frequently fail due to skin necrosis in the surrounding multiply-operated field. The objective of this case report is to present a surgical technique for successful closure of a large (2.5 cm) postauricular fistula using a vascularized cervico-occipital flap in a patient with a cochlear implant.Case Presentation We present the case of a 47-year-old female with a large postauricular fistula following multiple middle ear surgeries, including cochlear reimplantation via subtotal petrosectomy. After initial conservative antibiotic treatment, surgical fistula closure was performed using an advancement cervico-occipital flap pedicled on the occipital artery, combined with obliteration of the mastoid cavity with abdominal adipose tissue. The resulting donor-site defect was repaired with a full-thickness free skin graft from the abdomen. Perioperative and postoperative antibiotic therapy was guided by microbiological culture results. Intraoperative cochlear implant function measurements confirmed normal device performance. Histopathology demonstrated inflammatory granulation tissue with multinucleated giant cells. Microbiological culture yielded Staphylococcus aureus and Klebsiella oxytoca ESBL. Postoperative follow-up at two weeks, two months and one year demonstrated normal wound healing with no fistula recurrence.Conclusion Management of postauricular fistulas overlying cochlear implants is challenging due to poor tissue quality, biofilm formation on the device, and high rates of primary closure failure. This case demonstrates that a carefully planned surgical approach can achieve successful closure while preserving cochlear implant function. This technique may allow device retention while providing durable aesthetic and functional outcomes.