Label Free MLI® of Murine Brain Squash Preparation

Intraoperative histology is a cornerstone of surgical oncology, yet clinicians face a trade-off between speed and structural detail. Frozen sections can be rapid but give poor and variable histology, while standard histology gives rich architectural and histology information but only after the surgery is completed. This raw whole-slide MLI® of healthy murine brain tissue shows a label-free approach that captures detailed structural information without staining, or other chemical processing. 

Whole Slide MLI® of Murine Brain Squash

Intrinsic Contrast Without Labels

Without exogenous stains or fluorescent labels, MLI® uses tissue's intrinsic optical properties to generate contrasts. In this image, MLI® non-radiative intensity is mapped to blue, while two channels of multispectral MLI® radiative contrast are mapped to red and green. 

• Non-Radiative Contrast (Blue): Highlights nuclear structures and chromatin distribution through contrast associated with intrinsic DNA absorption. 

• Radiative Contrast (Red/Green): Reveals connective tissue and extracellular matrix architecture, complementing the nuclear detail captured in blue. 

  
  

Because contrast is derived directly from intrinsic tissue properties, MLI® can be performed on fresh tissue and requires no tissue clearing, embedding, sectioning, or chemical staining — only the time needed to put a thin slice of tissue between two glass slides for a squash preparation. 

Structural Detail and Diagnostic Relevance 

The selected zoomed regions highlight the microanatomical detail accessible with MLI®. Features commonly evaluated by pathologists for cancer diagnosis and margin assessment — nuclear morphology, cellular density, and local cellular organization — are clearly visible within the squash preparation. By imaging tissue in its native state, MLI® avoids artifacts commonly associated with frozen-section processing and variability introduced by staining and fixation. 

While this example uses healthy formalin fixed brain tissue, it illustrates the level of structural detail MLI® can capture in a rapid, label-free workflow — a capability that may eventually support intraoperative applications such as real-time tissue characterization and tumor margin assessment, directly within the surgical suite.