Facial nerve decompression via middle fossa approach for hyperostosis cranialis interna: a feasible therapeutic approach

Hyperostosis cranialis interna is an autosomal dominant disorder characterised by endosteal hyperostosis and osteosclerosis of the skull base and calvaria, leading to compression and dysfunction of cranial nerves I, It, VII and VIII. Case report: We report the use of bilateral surgical decompression of the internal auditory canals to treat hyperostosis cranialis interna in an eight-year-old girl presenting with bilateral facial palsy due to hyperostosis cranialis interna. Intervention and outcome: Using a middle fossa craniotomy approach, both internal auditory canals were unroofed and cranial nerves VII and VIII were decompressed, with a one-year interval between sides. The mimic function recovered. One year post-operatively, the right and left facial sides had been restored to House-Brackmann grades I and II, respectively. Conclusion: This is the first report of the use of surgical decompression of the internal auditory canal in a case of hyperostosis cranialis interna. Surgical decompression of the internal auditory canal is recommended therapeutically, but may also be performed prophylactically in younger patients with hyperostosis cranialis interna.