ICAR: endoscopic skull-base surgery.

BACKGROUND: Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS). METHODS: Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus. RESULTS: The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated. CONCLUSION: A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

Temporal patterns of 18 F-fluorodeoxyglucose positron emission tomography/computed tomography sinonasal uptake after treatment of sinonasal malignancy.

BACKGROUND: Current guidelines have identified 10 to 12 weeks posttreatment as the ideal time-point for improved diagnostic accuracy of positron emission tomography/computed tomography (PET/CT) for deep tissue sites of the head and neck. After treatment, the sinonasal skull base is predisposed to prolonged inflammation that may render this time-point inappropriate for initial posttreatment imaging surveillance for sinonasal malignancies. The purpose of this study is to evaluate temporal trends in 18 F-fluorodeoxyglucose (18 FDG) sinonasal uptake after treatment for sinonasal malignancies to better elucidate the optimal time-point for initial PET/CT posttreatment evaluation in this patient population. METHODS: A retrospective analysis of all successfully treated and non-locally recurrent sinonasal malignancies over a 15-year study period (2000 to 2015) was performed at our institution. Posttreatment 18 FDG PET/CT standardized uptake value data were collected and compared between various time-points (2 to 4 months, 5 to 12 months, 5 to 24 months, and 13 to 24 months) using an independent-samples t test. RESULTS: A statistically significant difference was noted between the posttreatment time windows 2 to 4 and 5 to 12 months (p = 0.048) as well as 2 to 4 and 5 to 24 months (p = 0.02). A trend toward significance was seen when comparing 2 to 4 and 13 to 24 months (p = 0.083). CONCLUSION: Our analysis of PET/CT in patients previously treated for sinonasal malignancy suggests that the posttreatment sinonasal skull base is characterized by a prolonged period of hypermetabolism that endures beyond the period previously described for deep tissue sites of the head and neck. These findings prompt a reevaluation of the previously described 10- to 12-week cutoff point for initial posttreatment PET/CT for head and neck squamous cell carcinoma as applied to sinonasal malignancies.