Closure of Skull Base Defects after Endonasal Endoscopic Resection of Planum Sphenoidale and Tuberculum Sellae Meningiomas

Abstract

Background: The expanded endoscopic endonasal transplanum transtuberculum approach allows tumor removal by minimally invasive procedures. A large dural and bone defect is created during the surgical procedure, increasing the risk of postoperative cerebrospinal fluid (CSF) leakage.

Objective: The aim of this study is to describe a surgical technique and complications observed in patients undergoing endonasal resection of planum sphenoidale and/or tuberculum sellae meningiomas.

Methods: A retrospective analysis was performed of patients with planum sphenoidale and/or tuberculum sellae meningiomas after expanded endoscopic endonasal resection between June 2013 and August 2018, in which autologous grafts, fascia lata inlay, and nasoseptal flap onlay were used for closure of skull base defects.

Results: Ten patients were included in the analysis. No cases of postoperative CSF leakages or meningitis were reported, whereas two patients evolved with postoperative infectious complications (fungal ball in right frontal sinus and brain abscess). The skull base defect created for resection measured, on average, 3.58 cm².

Conclusion: Our experience suggests that closure of skull base defects using combined fascia lata inlay and nasoseptal flap onlay is effective for preventing postoperative CSF leakage in resection of planum sphenoidale and/or tuberculum sellae meningiomas, and offers high reproducibility due to its low cost.

Keywords: Cerebrospinal fluid leak; meningioma; skull base; surgical flaps.

Figure 1

Illustration depicting sagital plane of skull base, divided into areas of endoscopic approach. (A) transfrontal; (B) transcribriform; (C) transplanal; (D) transtuberculum; (E) transellar; (F) transclival; (G) transodontoid. Transplanal and transtuberculum region highlighted in Green. Source: Angelo Shuman/Ricardo Dolci (2018)

Figure 2

Imaging in cadaver using 0o optic. (a) Exposure of whole posterior wall of sphenoid sinus, for performing craniectomy using endoscopic approach. (b) Green highlights showing whole region of bone opening for access to tuberculum and planum sphenoidale region, exposing dura-mater. (c) Opening of dura-mater in region of upper boundary. (d) Opening of dura mater allows visualization of hypophyseal stalk, superior hypophyseal artery, optic chiasm and superior intercavernous sinus

Figure 3

Intraoperative view. Step by step of endoscopic surgical field using 0°, 30° and 45° optics respectively. (a) Panoramic view of the posterior wall of the sphenoidal sinus. A large sphenoidectomy was performed to allow good visualization of the target area. (b) Dura mater after the opening of the sellar floor and suprasellar region (craniectomy). (c) Enlargement of the initial craniectomy using a Kerrison Roungeur

Figure 4

(a) The dural opening is made close to the midline and the lesion is thus identified, tumor debulking is first carried out by removing intratumor fragments to aid manipulation. (b) Removing the entire tumor after be dissected from adjacent structures. (c) After tumor resection, copious irrigation of the surgical cavity is mandatory, along with thorough hemostasis

Figure 5

(a) After harvested the fascia lata graft is placemented within of craniectomy. (b) Dural reconstruction was performed with an inlay fascia lata graft. (c) The onlay nasoseptal flap must then be placed with the perichondrial surface position onto the osseous part of the skull base and the pedicle does not become twisted as this will compromise irrigation of the flap and lead to necrosis. (d) The craniectomy region must be covered fully

Figure 6

Computed tomography image of head performed in first 24 hours postoperatively using Osirix software (Pixmeo, Switzerland) showing area and size of craniectomy. Image reconstruction on sagital, coronal and axial planes. (a) Image showing tuberculum sellae; and (b) planum sphenoidale meningioma craniectomy

Figure 7

Magnetic resonance imaging at 6 months postoperatively showing well-lodged fascia lata inlay and nasoseptal flap and absence of “dead space” between nasoseptal flap and sphenoid sinuses, important for preventing post-operative cerebrospinal fluid leakage