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Photonic Pathways
PHOTONIC PATHWAYS TOWARD REAL-TIME TISSUE ASSESSMENT
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Marie Louise GROOT *, Sylvia SPIES LaserLab Amsterdam, Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands * m. l. groot @ vu. nl
Photonics is transforming pathology by enabling fast, label-free tissue diagnostics. We developed Higher Harmonic Generation Microscopy( HHGM), a compact femtosecond-laser platform combining SHG, THG, and autofluorescence to image unprocessed tissue with submicron resolution. HHGM reproduces histological architecture within minutes, preserves tissue for further analysis, and enables AI-driven, real-time diagnostics across cancer types.
https:// doi. org / 10.1051 / photon / 202513430
Photonics has transformed modern medicine. Techniques such as optical coherence tomography( OCT) and white-light endoscopy, now standard tools in ophthalmology and gastroenterology, have brought optical precision to daily clinical practice, with tens of thousands of systems deployed worldwide. These technologies demonstrate the power of photonics to improve diagnostic accuracy, streamline workflows, and reduce patient burden. Yet, despite major advances in lasers, fiber optics, and nonlinear imaging, the full potential of photonics in healthcare remains largely untapped. Many areas of medicine still depend on slow, labor-intensive, or invasive diagnostic procedures. The challenge ahead is to match the rapid evolution of photonic innovation with clearly defined clinical needs, ensuring that solutions are neither overengineered nor underpowered for their purpose.
One such unmet need is the rapid assessment of tissue during surgery or biopsy. This article outlines the diagnostic bottleneck, the photonic principles that could overcome it, and our progress in developing higher harmonic generation microscopy( HHGM) as a fast, label-free alternative to conventional solutions.
THE DIAGNOSTIC BOTTLENECK Histopathology remains the cornerstone of cancer diagnosis. The technique, developed nearly two centuries ago, involves formalin fixation, paraffin embedding, sectioning, and staining of tissue with hematoxylin and eosin( H & E) to visualize nuclei, cytoplasm, and stroma. Pathologists then assess characteristic features of malignancy in tissue architecture and cellular morphology( such as nuclear enlargement, nuclear pleomorphism, and hyperchromatism), alongside immunohistochemical and molecular markers that guide treatment. The approach is highly reliable but slow: results typically take two to five days.
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