Laser Microbiopsy Could Provide Detailed Pathological Data with Limited Sample Damage

Oct 27, 2022 While they are considered the gold standard for disease diagnosis, including cancer, tissue biopsy and histological evaluation have significant limitations. Among these limitations are a biopsy's invasiveness and the time required for tissue processing. King discusses the initial success of an alternative biopsy approach that consists of a shaped laser beam for harvesting submicroliter (<1 mm3) tissue sections. In this approach, a Ho:YAG laser is shaped into an annular beam and focused onto the tissue to be sampled. The annular shape is ablated and the tissue section in the center of the annulus is ejected and collected by an overlying glass coverslip.

Tetrafluoroethane (R134A) is sprayed at the ablation site prior to ablation and at the collected tissue section post ablation to limit thermal damage and preserve histological features. Harvested microbiopsies can be analyzed using conventional histology or molecular diagnostic methods, or by emerging rapid diagnosis methods such as virtual hematoxylin and eosin (H&E) microscopy. Microbiopsies in King’s experiments were harvested from ex vivo porcine skin and kidney, stained with acridine orange (AO) and sulforhodamine 101 (SR101), imaged with a confocal microscope, and false-colored to create virtual H&E images. Virtual H&E images of harvested microbiopsies show histological features, including cell nuclei and collagen, that mirror conventional results.

***This presentation premiered during the 2022 BioPhotonics Conference. For more information on Photonics Media conferences, visit events.photonics.com.  

About the presenter
Jason King, Ph.D., recently graduated with his doctorate in biomedical engineering from the University of Texas at Austin, with a focus in biomedical optics. His work focuses on optimization of laser ablation for surgery and biopsy through temporal and spatial laser beam shaping. This work includes computational modeling and ablation experiments aimed at understanding light-tissue interactions involved in laser ablation. King’s other research interests include confocal microscopy and Raman spectroscopy for cancer diagnosis and monitoring.