How Tissue Spectroscopy Just Might Save Your Life

By John Oncea, Editor

The average person might not think about tissue spectroscopy in their daily life, but its applications have far-reaching impacts on healthcare and medical diagnostics that can benefit everyone. Here's why tissue spectroscopy matters.

Unless you conduct scientific research, make medical diagnoses, or take part in clinical applications, you probably don’t think about tissue spectroscopy much. Matter of fact, you might never have thought about it.

But the powerful technique has been around since its foundation was laid in the 1970s. As the years rolled by, techniques were developed and applied to characterize different aspects of tissue components, including matrix, scaffold, and cellular elements.

Optical spectroscopy methods have been refined for the non-invasive evaluation of engineered tissues, and new technologies like broadband diffuse spectroscopy have emerged, enabling the collection of in vivo data from human tissues that was previously not possible.

Today, according to the National Center for Biotechnology Information (NCBI), tissue spectroscopy encompasses a wide range of techniques, including fluorescence spectroscopy, Raman spectroscopy, and light scattering spectroscopy. These methods are used for various applications in tissue engineering, disease diagnosis, and monitoring of physiological states.

But why should any of this matter to you? Well, it might one day play a role in keeping you alive.

Current Uses Of Tissue Spectroscopy

Tissue spectroscopy is an analytical tool used in medical laboratories to study the chemical and physical properties of biological tissue samples, writes Massachusetts Institute of Technology. It uses spectroscopic techniques such as fluorescence spectroscopy, light scattering spectroscopy, and Raman spectroscopy to analyze the unique spectral patterns that are created as tissue progresses toward cancer. 

More specifically, it can be used to characterize tissue types such as colon, lung, cervix, and skin. It is also an aid in diagnosing disease at the biochemical, structural, or physiological level, adds ScienceDirect. For example, scientists have created a spectral database of known light-tissue interactions to analyze unknown tissue samples and produce a histologic diagnosis

Another benefit of tissue spectroscopy is its ability to monitor the physiological state of a tissue. For example, NCBI writes, Raman spectroscopy can be used to characterize articular cartilage degeneration and help select treatment strategies for cartilage repair surgery. 

Finally, according to AZo Materials (AzoM), advanced spectrometers can provide real-time imaging information during surgical procedures. 

Tissue spectroscopy is used in many fields, notes UW Medicine. Biomedical researchers use it to identify and characterize endogenous fluorescence species in tissues, as well as to study the chemical composition and metabolic state of tissues. They also use it to investigate tissue properties and metabolism non-invasively.

Doctors and clinicians employ tissue spectroscopy for disease diagnosis, such as distinguishing between malignant and normal tissues, monitoring the physiological state of tissues, and breast cancer imaging and brain mapping.

According to Spectroscopy, tissue engineers utilize spectroscopic techniques to assess the composition and development of engineered tissue constructs, determine the optimal timepoint for harvesting engineered tissues, and compare engineered tissues to native tissues.

In drug development, pharmaceutical researchers use tissue spectroscopy to map drug distribution in tissue samples and animal models and assess the efficacy of therapeutic molecules. They also use it to optimize drug candidates by understanding their tissue distribution.

Last but not least, spectroscopists and analytical chemists apply various spectroscopic techniques to tissue analysis, including:

• Fourier-transform infrared (FT-IR) spectroscopy
• Near-infrared (NIR) spectroscopy
• Raman spectroscopy
• Fluorescence spectroscopy

By using these techniques, professionals in various fields can gain valuable insights into tissue composition, metabolism, and pathology, advancing both basic research and clinical applications.

How It Works

Tissue spectroscopy involves measuring how electromagnetic radiation interacts with tissue samples, according to NCBI. When light of different wavelengths is directed at a tissue sample, the molecules within the tissue absorb, emit, or scatter the light in characteristic ways. This interaction produces a spectrum that serves as a molecular fingerprint of the tissue.

There are several spectroscopic techniques used for tissue analysis, starting with fluorescence spectroscopy, a technique that measures the emission of light from endogenous fluorescent molecules in the tissue when excited by light of a specific wavelength. Fluorescence spectroscopy can detect molecules like collagen, elastin, NADH, and tryptophan.

A second method, infrared spectroscopy, analyzes the absorption of infrared light by tissue molecules, providing information on molecular bonds and structures. Raman spectroscopy, on the other hand, measures the inelastic scattering of light by tissue molecules, providing detailed information about molecular vibrations and structures.

The method of tissue preparation can significantly impact spectroscopic measurements, NCBI writes. Common preparation methods include:

• Desiccation drying
• Ethanol dehydration
• Formalin fixation
• Analysis of fresh hydrated tissue

Each method may alter the biochemical information detected, so careful consideration of sample preparation is crucial.

Tissue spectroscopy has numerous applications in medical research and diagnostics including differentiating between healthy and diseased tissues, characterizing different tissue types, monitoring physiological states of tissues, and the early detection of cancer and other pathologies. It also comes with several advantages, including:

• Non-destructive analysis
• Requires minimal sample preparation
• Provides detailed biochemical information
• Can be automated for high-throughput screening

By analyzing the unique spectral signatures of tissues, researchers and clinicians can gain valuable insights into tissue composition, structure, and pathological states without the need for extensive sample processing or staining.

Why You Should Care

Tissue spectroscopy is revolutionizing how doctors identify and characterize tissues, especially for cancer detection. It also, for better or worse, is likely to impact your healthcare at some point during your life.

It allows for non-invasive diagnosis, reducing the need for painful biopsies and providing real-time analysis during surgical procedures, helping surgeons distinguish between healthy and cancerous tissue, according to AZoM. The technology also offers higher sensitivity and specificity compared to traditional diagnostic methods. For example, Raman spectroscopy has shown 83% sensitivity and 93% specificity in evaluating breast cancer specimens.

IOS Press adds that it can detect molecular changes in tissues before visible symptoms appear, as well as identify early-stage cancers before morphological changes, potentially allowing for earlier treatment and better outcomes. The technique is sensitive enough to monitor disease progression over time, which could be valuable for tracking treatment effectiveness.

Personalized Medicine

Spectroscopic analysis of tissues provides detailed molecular information, which can help advance personalized medicine and tailor treatments. It can identify specific biomarkers and metabolites associated with different diseases and conditions; molecular profiling that could lead to more personalized treatment plans based on your tissue characteristics.

Finally, as the technology develops, tissue spectroscopy is likely to become more widely available. IOS Press notes that portable and miniaturized devices are being developed, which could make the technology accessible even in remote or resource-limited settings. In addition, integration with existing medical tools, like endoscopes, is making the technology more practical for routine use.

While tissue spectroscopy is still primarily a research tool, its transition to clinical practice is accelerating. In the coming years, you may encounter this technology during cancer screenings, surgical procedures, or as part of routine health check-ups, offering you more accurate, less invasive, and potentially life-saving diagnostic capabilities.