Frontal sinus mucosa suture closure technique for prevention of cerebrospinal fluid rhinorrhea after bifrontal results

OBJECTIVE Bifrontal craniotomy often involves the bony opening and mucosal disruption of the frontal sinus (FS), which can lead to cerebrospinal fluid (CSF) leakage and meningitis. These complications are particularly associated with surgical treatments for skull base tumors and anterior cerebral artery aneurysms. The authors initially reported on the basic technique in 2014 with 51 cases. This study presents a detailed description of their technique and postoperative management for sealing the exposed FS during bifrontal craniotomy, including long-term follow-up results and outcomes. To objectively evaluate the effectiveness of suturing FS mucosa in preventing CSF leakage during bilateral frontal craniotomy, the authors focused only on anterior cerebral artery aneurysms. This limitation was necessary as other conditions, like extensive tumors or trauma, might lack intact FS mucosa or require its removal due to infection. METHODS The records of 34 consecutive patients (median age 62.0 years, mean 60.4 years, range 33-78 years) who underwent bifrontal craniotomy for anterior cerebral artery aneurysms between January 2014 and December 2023 were retrospectively analyzed. All patients had bony opening and mucosal injury of the FS (with exposure to the nasal cavity) that required mucosal suturing. This technique for sealing the exposed FS involves careful dissection of the mucosa from the entire sinus, sterilization with iodine-soaked surgical cotton, and preparation for closure. After the microsurgical procedure is completed, the exposed mucosa is sealed with 6-0 nylon sutures and further secured with fibrin glue-soaked Gelfoam. The bony exposure is covered with an autologous bone flap created from the inner table of the craniotomy bone flap. Finally, the frontal periosteal flap is sutured to the frontal base dura mater. Patients were instructed not to blow their noses for 2 months postoperatively. RESULTS Two patients experienced transient non-CSF leakage from the nasal cavity, likely due to irrigation fluid, which resolved within 2 days postoperatively. No recurrence was observed during a mean follow-up period of 52.8 +/- 41.7 months (median 49 months, range 3-127 months). No cases of meningitis or other intracranial infections were reported. CONCLUSIONS The long-term results demonstrate the sustained effectiveness of this technique in preventing postoperative complications related to FS exposure during bifrontal craniotomy.