The dural deviation ratio: a novel indicator for preoperative differentiation of intradural extension in spinal dumbbell schwannomas using Axial T2-weighted MRI.

Abstract

This study investigates the potential of using dural deviation in axial T2-weighted MRI to differentiate between Eden type-2 and type-3 spinal dumbbell schwannomas preoperatively. A retrospective analysis of 43 patients with spinal dumbbell Schwannomas was conducted. Tumors were classified into Eden type-2 or type-3 based on the need for dural incision during surgery. The dural deviation ratio (D-ratio) was measured using axial T2-weighted MRI. Statistical significance and diagnostic accuracy were assessed with Mann-Whitney U test and receiver operating characteristic (ROC) analysis. The authors declare no conflicts of interest and no funding sources for this study. The D-ratio was significantly higher in type-2 tumors (median: 0.904) than in type-3 tumors (median: 0.585) (p<.001). ROC analysis showed an AUC of 0.950, with a cut-off value of 0.746, 92.4% sensitivity, and 91.2% specificity. The D-ratio is a reliable indicator for distinguishing between type-2 and type-3 Schwannomas, with a cut-off value of 0.746.