ABSTRACT Objective There is limited consensus on endoscopic skull base surgery (ESBS) reconstruction principles. This study aims to generate comprehensive themes regarding ESBS reconstruction by pooling the experiences of ESBS experts, with comparison to a literature review of current published evidence. Methods Structured qualitative interviews of ESBS experts regarding postoperative management and reconstruction of various defect locations were conducted. Results A total of 68 experts comprising 40 academic teams across 13 countries with an average of 18 years of ESBS experience were included. We propose 10 stepwise algorithms for common skull base reconstruction scenarios based on these expert interviews. When available, the nasoseptal flap is used for all high_flow cerebrospinal leak defects. Multilayered reconstruction is favored at all anatomical subsites with increasing number of layers for increasing defect size and complexity. Heterogeneity exists in terms of inlay technique and materials, free grafting versus various pedicled flap options for low‐flow defects or in the absence of a nasal septum, nasal packing, tissue sealant, lumbar drain use, and postoperative management. Commonalities and discrepancies between experts were summarized. Conclusion Skull base reconstruction and post‐ESBS management is highly complex with a wide variety of practice patterns and expert strategies. Further research of higher quality evidence is warranted to identify optimal management patterns, though the current work aims to inform surgeons on these controversial areas by drawing from numerous experiences.
Orbital resection by intranasal technique (ORBIT): A new classification system for reporting endoscopically resectable primary benign orbital tumors
AbstractBackgroundThe Cavernous Hemangioma Exclusively Endonasal Resection (CHEER) staging system has become the gold standard for outcomes reporting in endoscopic orbital surgery for orbital cavernous hemangiomas (OCHs). A recent systematic review demonstrated similar outcomes between OCHs and other primary benign orbital tumors (PBOTs). Therefore, we hypothesized that a simplified and more comprehensive classification system could be developed to predict surgical outcomes of other PBOTs.MethodsPatient and tumor characteristics as well as surgical outcomes from 11 international centers were recorded. All tumors were retrospectively assigned an Orbital Resection by Intranasal Technique (ORBIT) class and stratified based on surgical approach as either exclusively endoscopic or combined (endoscopic and open). Outcomes based on approach were compared using chi‐squared or Fisher's exact tests. The Cochrane‐Armitage test for trend was used to analyze outcomes by class.ResultsFindings from 110 PBOTs from 110 patients (age 49.0 ± 15.0 years, 51.9% female) were included in the analysis. Higher ORBIT class was associated with a lower likelihood of gross total resection (GTR). GTR was more likely to be achieved when an exclusively endoscopic approach was utilized (p < 0.05). Tumors resected using a combined approach tended to be larger, to present with diplopia, and to have an immediate postoperative cranial nerve palsy (p < 0.05).ConclusionEndoscopic treatment of PBOTs is an effective approach, with favorable short‐term and long‐term postoperative outcomes as well as low rate of adverse events. The ORBIT classification system is an anatomic‐based framework that effectively facilitates high‐quality outcomes reporting for all PBOTs.
Quantitative Anatomic Comparison of Endoscopic Transnasal and Microsurgical Transcranial Approaches to the Anterior Cranial Fossa
BACKGROUND: Several microsurgical transcranial approaches (MTAs) and endoscopic transnasal approaches (EEAs) to the anterior cranial fossa (ACF) have been described. OBJECTIVE: To provide a preclinical, quantitative, anatomic, comparative analysis of surgical approaches to the ACF. METHODS: Five alcohol-fixed specimens underwent high-resolution computed tomography. The following approaches were performed on each specimen: EEAs (transcribriform, transtuberculum, and transplanum), anterior MTAs (transfrontal sinus interhemispheric, frontobasal interhemispheric, and subfrontal with unilateral and bilateral frontal craniotomy), and anterolateral MTAs (supraorbital, minipterional, pterional, and frontotemporal orbitozygomatic approach). An optic neuronavigation system and dedicated software (ApproachViewer, part of GTx-Eyes II—UHN) were used to quantify the working volume of each approach and extrapolate the exposure of different ACF regions. Mixed linear models with random intercepts were used for statistical analyses. RESULTS: EEAs offer a large and direct route to the midline region of ACF, whose most anterior structures (ie, crista galli, cribriform plate, and ethmoidal roof) are also well exposed by anterior MTAs, whereas deeper ones (ie, planum sphenoidale and tuberculum sellae) are also well exposed by anterolateral MTAs. The orbital roof region is exposed by both anterolateral and lateral MTAs. The posterolateral region (ie, sphenoid wing and optic canal) is well exposed by anterolateral MTAs. CONCLUSION: Anterior and anterolateral MTAs play a pivotal role in the exposure of most anterior and posterolateral ACF regions, respectively, whereas midline regions are well exposed by EEAs. Furthermore, certain anterolateral approaches may be most useful when involvement of the optic canal and nerves involvement are suspected.