Closure of spontaneous cerebrospinal fluid leakage via fistula at the lateral wall of the sphenoid sinus using a bone pile

This report describes a case of spontaneous cerebrospinal fluid leak through a narrow canal‐like fistula in the lateral wall of the sphenoid sinus, which was managed through rigid reconstruction. Rigid reconstruction of the skull base was performed by fitting a pile‐shaped bone into the fistula like the pile‐driving technique.