Autologous Fat Graft-Assisted Internal Auditory Canal Closure Technique after Retrosigmoid Transmeatal Resection of Acoustic Neuroma

Background: The retrosigmoid transmeatal approach remains an important strategy in the surgical management of acoustic neuromas. Gross total resection of acoustic neuromas requires removal of tumor within the cerebellopontine angle as well as tumor involving the internal auditory canal (IAC). Drilling into the petrous bone of the IAC can expose petrous air cell tracts, which can potentially result in a fistulous tract to the nasopharynx manifesting as cerebrospinal fluid (CSF) rhinorrhea. We evaluated our method of IAC closure using autologous fat graft and assessed the rates of postoperative CSF leakage.

Methods: We performed a retrospective study of 18 patients who underwent fat graft-assisted IAC closure after retrosigmoid transmeatal resection of acoustic neuroma. We assessed rates of postoperative CSF leak (incisional leak, rhinorrhea, and otorrhea), pseudomeningocele formation, and occurrence of meningitis.

Results: A total of 18 patients (8 males and 10 females) with a mean age of 50.6 years (range, 18–68 years) underwent fat graft-assisted IAC closure. No lumbar drains were used postoperatively. Gross total and near-total resection was achieved in all the patients. There were no instances of postoperative CSF leak (incisional leak, rhinorrhea, and otorrhea), pseudomeningocele formation, or occurrence of meningitis. There were no graft site complications.

Conclusion: Our results demonstrate that autologous fat grafts provide a safe and effective method of IAC defect closure to prevent postoperative CSF leakage after retrosigmoid transmeatal resection of acoustic neuromas.