H‐Aggregated Squaraine Probe NIR‐II/MRI Double Reversal Imaging for Liver Cancer Precise Surgical Navigation

-weighted MRI, brightening liver tumors. Intraoperatively, the same aggregates quench NIR-II fluorescence, darkening tumors against normal tissue and allowing clear visualization of sub‑2 mm lesions. Additionally, fluorescence can be restored ex vivo by solvent extraction, enabling real-time confirmation of complete resection. To our knowledge, this is the first small-molecule dual-modal probe that utilizes in vivo ACQ to achieve bright/dark reversible contrast across both MRI and NIR-II imaging, offering a powerful tool for precise liver cancer surgery.