Abstract: Objective  Traditional classification systems for skull base lesion surgeries fail to accurately reflect the differences in surgical difficulty.This study aims to establish and validate a multi-dimensional grading sclae for skull base tumor surgical difficulty,to guide clinical decision-making and resource optimization.Methods A total of 131 patients with skull base tumors who underwent surgery at West China Hospital of Sichuan University in 2018 were included in this study.Based on the selfdeveloped “grading scheme for surgical difficulty of skull base tumors” (encompassing nine dimensions such as involved regions,arteries,nerves,and tumor characteristics),patients were categorized into grades Ⅰ-Ⅳ.The baseline data,imaging features,surgical indicators and postoperative outcomes of each group were analyzed to verify the clinical applicability of the scale.Results The surgical difficulty increased progressively from grade Ⅰ to Ⅳ,with significant differences observed in core dimensions such as involved regions,arteries,and nerves (all P<0.05).As the difficulty level increased,the intraoperative blood transfusion rate (0→38.1%),operation time [(1.6±1.5)h →(7.3±4.2)h],hospital stay [(7.6±2.7)d→(15.9±15.2)d],and postoperative complication rates (15.5→52.4%) also increased significantly (all P<0.05).Conclusion This system enables quantitative evaluation-based surgical difficulty gradient classification,compensating for the limitations of the traditional classification system.It provides a scientific foundation for personalized surgical approach selection,DRG-based fine payment,physician training,and promotes the standardized development of the skull base subspecialty.

Key words: skull base neoplasms, grading, surgical difficulty, neurosurgery, classification