Location-specific outcomes and complications of endoscopic transorbital approaches: A systematic review with novel anatomical grouping.

Introduction: Endoscopic transorbital approach (ETOA) is gaining recognition due to lower complication rates and better cosmetic outcomes. Nonetheless, there is no clear anatomical grouping system for lesions that ETOA can address, and location-specific complication rates are still lacking. Research question: This systematic review provides an anatomical grouping system for ETOA and analyse the location-specific surgical risks and outcomes. Material and methods: Based on the PRISMA guideline, articles with keywords "Endoscopic" and "Transorbital" were searched and analysed. The cases included are regrouped based on four anatomical locations (I - orbital, II - cavernous sinus, III - extradural, IV - intradural), and outcomes are studied respectively. Results: Data from 28 published articles with 382 patients were identified. There were 113 orbital lesions, 58 cavernous lesions, 18 extradural lesions, and 150 intradural lesions. There was significant post-operative visual acuity improvement in Groups I (70.6 %), II (56.3 %), and IV (63.3 %). Proptosis shows notable improvement rates across all groups, particularly in Groups II (95.7 %) and IV (87.0 %). There was an observed difference in the rate of CSF leak depending on the location of the lesion: 0 % in both Group I and II versus 11.8 % in Group III and 3.4 % in Group IV (p=0.005). Discussion and conclusion: This systematic review proposed an anatomical grouping system to analyse location-specific outcomes for ETOA. Our findings highlighted the significance of this new classification for anatomy-based risk assessment. Future, larger-scale, and multicenter research will generate more data, allowing for further stratification of outcomes based on specific pathology subtypes.