Ex vivo validation of wide-field imaging Mueller polarimetry for real-time neurosurgical brain tissue differentiation

Accurate intraoperative differentiation of brain tumor boundaries during surgery is essential to maximize resection while preserving healthy tissue. We present a wide-field imaging Mueller polarimeter designed for real-time, high-quality brain tissue visualization. The system performs complete Mueller matrix reconstruction using rapid, non-mechanical polarization modulation to map key polarimetric parameters, including linear retardance, depolarization, and azimuth of optical axis correlated with fiber orientation. Validated ex vivo on thick formalin-fixed human brain samples, the system achieved high image quality and signal-to-noise ratios comparable to a previously validated ferroelectric liquid crystal-driven system. Polarimetric maps enabled tissue differentiation of gray matter, white matter, and tumor regions, supporting its potential for accurate brain tissue differentiation. This work demonstrates the feasibility of using wide-field Mueller polarimetry for real-time brain tissue analysis and lays the groundwork for integration into neurosurgery. Ongoing efforts focus on in vivo validation and clinical translation to enhance surgical precision during glioma resection.