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Operative Interventions for Clivus Osteoradionecrosis with CSF Leak following Stereotactic Radiosurgery for Nasopharyngeal Carcinoma

Objectives: Nasopharyngeal carcinoma (NPC) local recurrence still represents a major clinical challenge and a high mortality and morbidity cause. The authors report a case of a 44-year-old male with clivus osteoradionecrosis (ORN) and dural radionecrosis who presented with cerebrospinal fluid (CSF) leak, 6 months after a boost of stereotactic radiosurgery using gamma knife for the treatment of locally recurrent NPC, following conventional external beam radiotherapy (EBRT) with chemotherapy. Methods: A direct transnasal endoscopic-assisted approach with multiple reconstructive pedicled flap technique was used to achieve watertight dural reconstruction. Results: Despite CSF leak recurrence, after the second attempt we achieved a successful clivus reconstruction using a bilateral posterior pedicle inferior turbinate flap (PPITF). The reconstruction withstood a watertight seal for 1 month, until patient death from cardiopulmonary arrest as a result of ventilator-associated pneumonia. Conclusions: We recommend an early diagnosis and surgical intervention in the setting of clivus ORN. Local debridement of necrotic bone is critical for local nasal graft adherence and survival. The evidence of dural radionecrosis is a predictor of bad prognosis. As a result, broad dural defect exposition should be the standard procedure with the use of a multi-layered technique combined with vascularized pedicle flaps regardless of the dural tear dimension.