Unfreeze the frozen, and beyond: slide-free histology is coming

Novel slide-free histology (SFH) technologies, including confocal, light-sheet, multiphoton microscopy, and microscopy with UV surface excitation (MUSE), can generate high-fidelity H&E-like images directly from fresh tissue in minutes. This approach bypasses the freezing, sectioning, and artifacts inherent to conventional frozen sections and real-time onsite evaluation (ROSE), while fully preserving the specimen for definitive FFPE and molecular testing. SFH methods can also replace formalin- and paraffin-based conventional histology, with its own complexity and delay. These new methods have demonstrated diagnostic accuracy comparable to frozen sections and show strong concordance with permanent histology across multiple organ sites. Furthermore, imaging thick specimens reveals structural tissue elements not easily appreciated on thin sections.