A team at the University of Arizona is working on innovative optical technology designed to penetrate biological tissues, particularly skin and soft tissues inside the body. This cutting-edge approach aims to improve the diagnosis of skin cancers, which are the most common form of cancer globally, assisting doctors in evaluating tumor invasion and monitoring treatment efficacy.
The research team is among a select few in the United States to receive funding under the “Advancing Non-Invasive Optical Imaging Approaches for Biological Systems” initiative. They will focus on creating a non-invasive imaging method known as synthetic wavelength imaging (SWI). This technique employs two distinct illumination wavelengths to computationally produce one virtual, “synthetic” imaging wavelength. The advantage of the synthetic wavelength is its increased resistance to light scattering within biological tissues, while still utilizing the high-contrast information available from the original wavelengths.
The principal investigator, Florian Willomitzer, an associate professor of optical sciences, emphasized that the project specifically addresses nonmelanoma skin cancers, including basal cell carcinoma and squamous cell carcinoma. These types of skin cancers exhibit different imaging contrast properties compared to melanoma, which presents unique challenges in developing new “deep” imaging technologies.
Traditional imaging techniques, such as confocal microscopy and optical coherence tomography, utilize light wavelengths that fall within the visible to near-infrared spectrum. While these methods provide excellent contrast and resolution at shallow depths, their shorter wavelengths are more prone to scattering in deeper tissues. Conversely, longer wavelength techniques like ultrasound can penetrate deeper but often compromise on resolution and the necessary contrast for certain cancer types.
The goal of the research is to create imaging tools that are flexible enough to accurately assess tumor margins at diagnosis while being reliable for tracking how lesions respond to treatment over time. Achieving this necessitates tunable imaging capabilities that harmonize depth penetration with resolution and contrast, a balance that current technologies frequently fail to provide.
The study aims to push past these limitations by developing technologies that enable high-resolution, non-invasive imaging through tissue. Enhanced imaging techniques could lead to earlier detection of medical conditions, improved assessment of cellular and tissue health, and advancements in non-invasive treatment methods, potentially replacing the need for surgical interventions.
The experiments will also focus on capturing rapid biological processes, such as muscle contractions and pulse, in real time. “The resilience of synthetic wavelength imaging to scattering in deep tissue, combined with high tissue contrast at the original optical wavelengths, is a unique advantage,” stated Willomitzer. “Our approach seeks to overcome the traditional trade-offs between resolution, depth, and contrast through advanced computational evaluation algorithms.”
If successful, the project could enable earlier detection of invasive lesions, more precise identification of tumor margins, and real-time monitoring of responses to non-invasive treatments, thereby enhancing the effectiveness of new therapeutic strategies. The research team has received nearly $2.7 million from the National Institutes of Health“s Common Fund Venture Program to develop next-generation imaging technologies that provide clearer, deeper views inside the body without invasive procedures.
