10049-ST-4 Association Between Intra-tumoral Hypointensity on Susceptibility-Weighted MRI and Hemorrhage After Stereotactic Brain Biopsy

Abstract Objective This study aimed to evaluate the relationship between intra-tumoral susceptibility signals (ITSS) observed on preoperative susceptibility-weighted imaging (SWI) and the risk of postoperative hemorrhage following STB. Methods A retrospective analysis was conducted on 66 consecutive patients who underwent STB at our institution. ITSS was defined as the presence of dot-like or linear hypointensities on SWI and graded as follows: grade 1 (absent), grade 2 (1-10 foci), and grade 3 (>10 foci). ITSS grading was independently performed by two experienced physicians. Associations between ITSS grade and postoperative hemorrhage were assessed, along with potential confounding factors including age, coagulation profile, medical history, tumor location, and histopathological diagnosis. Results Postoperative hemorrhage occurred in 17 patients (25. 8%), including 10 cases (15. 2%) with hemorrhage exceeding 10 mm in diameter. The maximum hemorrhage diameter increased significantly with ITSS grade (mean ± SD: grade 1, 1.78 ± 1.35 mm; grade 2, 2.98 ± 2.2 mm; grade 3, 9.51 ± 2.11 mm; p = 0.01). Notably, grade 3 ITSS was strongly associated with hemorrhages >10 mm, with an odds ratio of 9.73 (95% CI: 1. 57-60. 5), and emerged as the sole independent predictor among the variables examined. Discussion These findings were subsequently validated in a large-scale French cohort, underscoring their robustness and generalizability. Ongoing efforts are directed toward the quantitative assessment of ITSS and the evaluation of region-specific hemorrhagic risk within tumors through multicenter collaborative studies. Conclusion ITSS grading on preoperative SWI provides a valuable imaging biomarker for stratifying the risk of hemorrhage following stereotactic brain biopsy and may inform preoperative risk assessment and surgical decision-making.