Technique for Frontal Sinus Preservation during Repair of Cerebrospinal Fluid Leak after Trauma or Surgery

Background The surgical management of frontal sinus fractures has evolved over the past century. Cranialization of the frontal sinuses with complete removal of the mucosa and plugging of the frontal ducts is widely accepted for the treatment of cerebrospinal fluid (CSF) leak after traumatic injury or opening of the frontal sinus during surgery. More recently, the field has moved toward attempts at sinus preservation strategies. We describe a technique for repair of CSF leak using allograft onlay and vascularized periosteal flap with preservation of frontal sinus function.

Methods Our technique of preserving the frontal sinus when repairing CSF leak secondary to posttraumatic fracture of the frontal sinuses and anterior skull base consists of the following steps: (1) A bicoronal skin flap with harvesting of a pedicled periosteal flap, (2) a bifrontal craniotomy with exposure of the frontal sinuses, (3) the posterior table of the fontal sinuses and the mucosa are only partially removed and the frontal ducts are not plugged, (4) An onlay dural allograft is placed over the dura, then the pericranial flap is placed between the allograft onlay and the skull base thus separating the frontal sinus from the intracranial space. The same technique is used after planned surgical entry of the frontal sinuses. We retrospectively reviewed all cases of frontal sinus repair using the aforementioned technique at our institution (N = 18). Patients were followed up for a minimum of 6 months.

Results Total 18 patients underwent the described frontal sinus repair technique: 13 for tumor and 5 for trauma. One patient had a lumbar drain placed at the time of operation. There were no CSF leaks. Five patients died due to either progression of their original disease (four out of five) or massive PE in the posttraumatic period (one out of five). There were no complications that could be attributed to the surgical technique.

Conclusion This technique allows repairing CSF leak after surgery or trauma while preserving the frontal sinus function. No patient required additional treatment for CSF leak, and because the frontal duct is not plugged, the risk of mucocele should be minimal. More delayed follow-up is obviously needed to evaluate the incidence of mucocele formation.