Closure of Large, Secondary Skull Base Defect following Craniofacial Tumor Resection and Adjuvant Chemoradiation Therapy Using a Free, Microvascularly Anastomosed Radial Forearm Fascial Graft: A Case Report

Objective: Secondary skull base defects with persistent CSF leak following ablative surgery and tissue irradiation pose a major threat to the patients concerned, as well as a true challenge for the treating surgical team.

Methods: We present a case of a large, anterior skull base defect almost 2 years after craniofacial resection (including right orbital contents), reconstruction with synthetic material and an anterolateral thigh free flap as well as postoperative, adjuvant chemoradiation therapy of a large adenocarcinoma originating from the right paranasal sinuses. The patient was admitted with a large, frontal lobe abscess with connection to the right paranasal sinus system as well as to the right lateral ventricle.

Results: The patient was stabilized via high dose, calculated antibiotic therapy. Transcranial efforts to close the defect using a combination of a pericranial flap and synthetic material proved ineffective. Via lateral rhinotomy approach, the defect area was debrided from necrotic tissue, and a free radial forearm fascial flap was sewn into place, anastomosed to the cervical vasculature and supported by fibrin glue and temporary tamponades. The defect healed up well without another occurrence of intracranial infection and/or CSF leak.

Conclusion: Vascularized free tissue grafts are an option in difficult skull base reconstructions even after extensive surgery and chemoradiation therapy. This statement is supported by numerous, mostly single case reports in the medical literature, which are discussed and put in relation to the current case.