Techniques for Skull Base Reconstruction in Endoscopic Surgery

Indications and Preoperative Considerations

• Postoperative CSF leak is one of the most important complications secondary to endoscopic skull base surgery.

• Skull base reconstruction techniques have been instrumental for the development of endoscopic skull base surgery. Continuous research has been done during the past decade on new approaches, techniques and materials to improve its clinical results.

• Currently, the endoscopic endonasal approach is the preferred method for repair of anterior skull base and cerebrospinal fluid leakage in the majority of cases.

• Besides being less invasive than its transcranial counterpart, different clinical series have demonstrated that endoscopic skull base repair is effective in over 90% of cases for closure of CSF leaks.

• Numerous variations for the construction of skull base repair have been proposed, including:

  • Autologous materials: fascia lata, fat and pericranium grafts

  • Synthetic materials: Duragen, Duraseal

  • Bone flaps

  • Mucosal flaps: rescue flaps, turbinate flaps, Hadad–Bassagasteguy flap.

• The vascularized nasoseptal flap or Hadad–Bassagasteguy (HB) flap is one of the most important technical developments of endoscopic surgery. It has a major role in the feasibility of extended approaches to the anterior, middle and posterior fossa, reducing the risks of postoperative CSF leakage in large skull base defects, to less than 5%.

• Advantages of using a pedicled flap:

  • Promotion of rapid healing.

  • Provision of an effective barrier against CSF leaks.

  • Wide arc of rotation: the surgeon is able to reach defects from the frontal sinus to the lower clivus.

• Different techniques may be applied for sellar reconstruction, including insertion of fat grafts and biological sealants, gasket seal and multilayer reconstruction techniques.

• The surgeon must plan the skull base reconstruction depending on:

  • Etiology of the skull base defect.

  • If the defect has been a consequence of tumor resection it is important to consider the pathology, the location of the lesion and if the lesion requires further debulking.

  • When intraoperative CSF leakage is expected and/or observed (e.g. while resecting the suprasellar component).