Reconstruction after endoscopic surgery for skull base malignancies.

ABSTRACT

INTRODUCTION: The ability to resect malignancies of the ventral skull base using endoscopic endonasal approaches has created a need for effective endoscopic reconstructive techniques. The purpose of this review is to summarize current techniques for reconstruction of large skull base defects during endoscopic endonasal surgery. METHODS: Recent medical literature was reviewed to identify techniques and best practices for repair of skull base defects during endoscopic endonasal surgery. Preference was given to evidence-based recommendations. RESULTS: Superior results are observed with multilayer inlay/onlay grafts supplemented with vascularized flaps. The nasoseptal flap is the primary reconstructive flap for most defects; secondary choices include the lateral nasal wall flap and extracranial pericranial flap. Clival defects are particularly challenging and are further augmented with adipose tissue to prevent pontine herniation. Perioperative management including the use of lumbar cerebrospinal fluid drainage minimizes the risk of a postoperative leak in high-risk patients. Postoperative cerebrospinal fluid leaks are managed similarly to primary leaks and may require use of a secondary vascularized flap. Complications of reconstructive flaps include flap necrosis and cosmetic nasal deformity. CONCLUSION: Large defects of the anterior, middle, and posterior cranial fossae can be managed similarly by adhering to basic principles of reconstruction. Future developments will improve stratification of patients into reconstructive groups and allow tailored reconstructive algorithms. New biomaterials may replace autologous tissue and facilitate endoscopic repair. Improved monitoring will allow for assessment of the reconstructive site with early detection and repair of postoperative cerebrospinal fluid leaks.