Looking for a perfect match: multimodal combinations of Raman spectroscopy for biomedical applications

Abstract

. Raman spectroscopy has shown very promising results in medical diagnostics by providing label-free and highly specific molecular information of pathological tissue ex vivo and in vivo . Nevertheless, the high specificity of Raman spectroscopy comes at a price, i.e., low acquisition rate, no direct access to depth information, and limited sampling areas. However, a similar case regarding advantages and disadvantages can also be made for other highly regarded optical modalities, such as optical coherence tomography, autofluorescence imaging and fluorescence spectroscopy, fluorescence lifetime microscopy, second-harmonic generation, and others. While in these modalities the acquisition speed is significantly higher, they have no or only limited molecular specificity and are only sensitive to a small group of molecules. It can be safely stated that a single modality provides only a limited view on a specific aspect of a biological specimen and cannot assess the entire complexity of a sample. To solve this issue, multimodal optical systems, which combine different optical modalities tailored to a particular need, become more and more common in translational research and will be indispensable diagnostic tools in clinical pathology in the near future. These systems can assess different and partially complementary aspects of a sample and provide a distinct set of independent biomarkers. Here, we want to give an overview on the development of multimodal systems that use RS in combination with other optical modalities to improve the diagnostic performance.

Understanding immunity in a tissue‐centric context: Combining novel imaging methods and mathematics to extract new insights into function and dysfunction*

“…We think that the combination of inventiveness in individual laboratories, combined with the growing investments by commercial vendors in the imaging space, points to a rich future of discovery using spatial analytical methods applied in combination. New techniques for spatial metabolomics, 130 label‐free imaging, 131 and light‐sheet 132 and light‐field 121 imaging, together with spatial transcriptomic approaches 133 and algorithms for improving the resolution and registration of very large imaging data sets, will enhance the depth and extent of information we can gather at the tissue level. Approaches such as the correlative IVM + static imaging we introduce here can connect the critically important dynamic characteristics of immune cell populations with static omic‐scale analyses that span the molecular to organ level.…”

Advances in the application of Raman spectroscopy in haematological tumours

“…However, the high specificity of Raman spectroscopy comes at a cost. The acquisition rate is low, depth information cannot be directly accessed, and the sampling area is limited ( Schie et al, 2021 ).…”

The complementary value of intraoperative fluorescence imaging and Raman spectroscopy for cancer surgery: combining the incompatibles

“…The combination of other imaging modalities with selective sampling of suspicious areas by RS as a powerful labelfree analytical technique has also been explored [128,129]. Such approaches include MRI, second harmonic generation, OCT, AFI, total internal reflection fluorescence, or quantitative phase microscopy [130][131][132][133][134][135][136][137][138].…”