In Vivo Hyperspectral Imaging of Vasogenic Edema and Cortical Oxygenation in Meningiomas: A Subgroup Interim Analysis of a Prospective Study.

Abstract

Peritumoral brain edema (PBE) is common in intracranial meningiomas (IM) and has been linked to postoperative morbidity, yet its impact on cortical oxygenation remains unclear. We investigated the association between PBE and local tissue oxygenation using intraoperative in vivo hyperspectral imaging (HSI). Twenty-nine patients undergoing microsurgical IM resection with intraoperative HSI were prospectively analyzed. Peritumoral cortical oxygen saturation (StO2) was quantified and correlated with preoperative MRI parameters, including edema volume and contrast-enhancement intensity. Patients were stratified by PBE presence and histopathological subtype (meningotheliomatous vs nonmeningotheliomatous). Group comparisons used t-tests; correlations used Pearson coefficients. PBE was present in 17 (58.6%) cases. Patients with PBE exhibited significantly lower cortical oxygenation than those without (mean StO2 0.49 ± 0.13 vs 0.59 ± 0.10, P = .048). Within the PBE group, edema volume correlated positively with StO2 (r = 0.58, P = .015), whereas tumor contrast enhancement intensity correlated inversely with StO2 (r = -0.59, P = .013). No significant correlation was observed in patients without PBE (r = -0.26, P = .18). Meningotheliomatous IMs showed a trend toward lower StO2 compared with nonmeningotheliomatous tumors (0.51 ± 0.17 vs 0.55 ± 0.07, P = .05). PBE in IMs is associated with impaired cortical oxygenation. Larger PBEs paradoxically showed higher StO2, suggesting compensatory mechanisms, while strong tumor enhancement correlated with local hypoxia. These findings suggest that intraoperative HSI may serve as a promising tool for characterizing tumor-brain interactions and support further investigation into PBE pathophysiology.