Rapid brain structure and tumour margin detection on whole frozen tissue sections by fast multiphotometric mid-infrared scanning

Abstract

Frozen section analysis is a frequently used method for examination of tissue samples, especially for tumour detection. In the majority of cases, the aim is to identify characteristic tissue morphologies or tumour margins. Depending on the type of tissue, a high number of misdiagnoses are associated with this process. In this work, a fast spectroscopic measurement device and workflow was developed that significantly improves the speed of whole frozen tissue section analyses and provides sufficient information to visualize tissue structures and tumour margins, dependent on their lipid and protein molecular vibrations. That optical and non-destructive method is based on selected wavenumbers in the mid-infrared (MIR) range. We present a measuring system that substantially outperforms a commercially available Fourier Transform Infrared (FT-IR) Imaging system, since it enables acquisition of reduced spectral information at a scan field of 1 cm2 in 3 s, with a spatial resolution of 20 µm. This allows fast visualization of segmented structure areas with little computational effort. For the first time, this multiphotometric MIR system is applied to biomedical tissue sections. We are referencing our novel MIR scanner on cryopreserved murine sagittal and coronal brain sections, especially focusing on the hippocampus, and show its usability for rapid identification of primary hepatocellular carcinoma (HCC) in mouse liver.

Spatial omics imaging of fresh-frozen tissue and routine FFPE histopathology on a single cancer needle core biopsy: freezing device and multimodal workflow

“…This can be avoided by using spatially resolved techniques (here, MSI and IRI) and a pathologist-annotated, H&E stained reference sections confirming tissue types. In line with the primary aim of this study, namely to show the clinical feasibility of the proposed However, also other spatially resolved techniques like IRI may be beneficial in clinical tissue diagnostics 26,28,47 . Using annotated ROI (e.g., tumor and non-tumor) as labels, spectral differences can be used to guide clinicians in their disease investigation.…”

“…However, also other spatially resolved techniques like IRI may be beneficial in clinical tissue diagnostics 26,28,47 . Using annotated ROI (e.g., tumor and non-tumor) as labels, spectral differences can be used to guide clinicians in their disease investigation.…”

“…Moreover, studies often combine complementary imaging techniques to access the complex biomolecular context of a sample and to allow more sophisticated so-called multimodal workflows [23][24][25][26] : Label-free imaging techniques that can be performed on the same tissue section prior to MSI are infrared imaging (IRI) and IR microscopy. Due to recent technological innovations in vibrational spectroscopy, IR methods enable rapid screening and examination of tissue section for tumor margin detection, classification and grading 24,[27][28][29][30] . Similar to correlative histology-based MSI approaches 31 , morphological features obtained with IR spectroscopy yield accurate labels for precise region-specific MSI-based molecular fingerprinting 24 ("IRI-guided MSI").…”

Establishing Reliable Research Data Management by Integrating Measurement Devices Utilizing Intelligent Digital Twins

“…Some of these imagers and measuring devices were developed, built, and are currently operating at the institute itself. Representatives of these self-developed and manufactured measuring devices are the MIR scanner [ 36 ], the Multimodal Imaging System [ 37 ], and a multipurpose, multichannel photometer. The MIR scanner is used for generating hyperspectral images of tissue sections and consists of a laser unit with four lasers with different wavenumbers, a detector unit, a focusing unit, an agile mirror unit, and a movable object slide.…”

“…The MIR scanner is used for generating hyperspectral images of tissue sections and consists of a laser unit with four lasers with different wavenumbers, a detector unit, a focusing unit, an agile mirror unit, and a movable object slide. It is used for frozen section analysis in tumor detection for the identification of tissue morphologies or tumor margins [ 36 ]. The Multimodal Imaging System also generates hyperspectral data for tissue sections with various procedures and consists of a modular upright light microscope combined with a Raman Spectrometer, a visible (VIS)/Near-Infrared (NIR) reflectance spectrometer, and a detector unit.…”