Soft Gasket Seal: Refining the Closure Technique following EEA: Case Series and Review of Literature

Introduction: Endoscopic endonasal approaches (EEA) have become the standard for various skull base pathologies, but cerebrospinal fluid (CSF) fistula has been a main concern. After the introduction of the nasoseptal flap by Hadad et al in 2006, the rates of CSF fistula have dramatically decreased. Since then, several authors attempted to improve the technique, with some proposing a multilayered closure. In such a closure, a rigid buttress (autologous bone or cartilage or some synthetic absorbable material) is employed in addition to the nasal septal flap to keep the construct in place. Herein, we propose a refinement of this technique, not requiring the use of rigid materials known as “Soft Gasket Seal (SGS).” This is distinct from the already described “Gasket Seal.” In addition, we present a series of craniopharyngioma to illustrate such concept.

Materials and Methods: Data for patients undergoing EEA for craniopharyngioma were retrospectively reviewed. These included demographic, clinical, operative, radiographic, and pathological information. Incidence of postoperative complications and CSF leaks were recorded. Descriptive statistical analysis was performed. The patients were categorized in one of two groups of closure technique, SGS and non-SGS, and compared. The SGS technique is described as follows: a piece of Duragen, at least 10 mm larger than the dural defect, is placed over the defect. Then, its central portion is gently pushed in, producing a small central depression, which is filled in with small pieces of Gelfoam. Next, the Duragen borders are checked for any gaps. If any breach is identified, more pieces of Gelfoam are added until there are no gaps. Subsequently, for both techniques the nasoseptal flap is placed over the construct, followed by Gelfoam, Merocel, and/or Nasopore, as usual.

Results: There were 31 patients operated between 2010 and 2018, and the SGS was used in 13. The mean age was 42.9 years (range: 12–78), the mean follow-up was 36 months (range: 3–91), and the mean hospital length of stay was 5.4 days (range: 2–22). Sixty-four percent were female. There were three CSF leak cases (9.6%), one in the SGS (7.6%) and two in the non-SGS (11.1%), p > 0.05.

Discussion: EEA has revolutionized the skull base surgery and the nasoseptal flap has dramatically reduced the CSF fistula rates. Previous authors described the use of rigid materials and/or fat graft as an adjuvant technique for closure, sometimes requiring dural sealants and lumbar drains. Our SGS technique, which is really simple to apply, showed to be feasible with acceptable results and no need for adjuvants.

Conclusion: The Soft Gasket Seal technique is a simple, safe, and feasible technique, associated with CSF leak rates comparable to previous techniques. This could impact on hospital length of stay and complication rates overall.