LASER 2022: Forum reviews progress in biophotonics, medical imaging

26 Apr 2022

Research and industrial speakers give updates on breakthroughs, benefits, and market needs.

by Matthew Peach in Munich

Applications of biophotonics in medicine – the focus of this morning’s forum at LASER World of Photonics – have significantly evolved over the past several years in various respects. In-vitro diagnostics based on biophotonic methods and phenomena is an integral part in pathology and laboratory medicine, while new methods are continuously being integrated.

After a welcome by forum chairman Prof. Ronald Sroka of LIFE Zentrum / LMU Klinikum, Munich, the opener was Dr. Christian Homann of Ferrosens, a spin-off of the Laser Research Laboratory, an institute of the LIFE Center, at the University Hospital Munich. The company was founded in July 2017 to develop a portable instrument to measure the iron parameter Zinc Protoporphyrin, an indicator of diseases caused by iron deficiency.

Detecting iron deficiency

Dr. Homann explained how his company’s non-invasive measurement technique FerroSens enables “wide-spread screening for iron deficiency through its simple and fast method – without the need for blood withdrawal. In this way, FerroSens is helping to fight iron deficiency, the world's most common nutritional deficiency,” he said.

He said, “By using spectroscopy and doing some clever evaluation we can really learn a lot using optical techniques in medicine. Hopefully, we will have some benefits and get better diagnoses in the future.”

Dr. Jan Philip Kolb of the Medical Laser Center, at Lübeck, gave a presentation entitled Slide-free Histology with Fiber Laser-based Multiphoton Microscopy. “In our work, we are able to image H- and E-stained specimens with our patented fiber laser technology. Furthermore, we could take the previous work that showed that you can excite H and E with multiphoton microscopy a step further by showing that we have developed a technique that can also be applied to the surgical theater,” he explained

“Therefore we also hope that since we use these two stains, H and E, that medical professionals will have a greater acceptance for our technique, and that we also have lower barriers to medical device certification, later on.”

Startup in planning

Dr. Kolb concluded, “We have the goal to turn our lab set up into a med device by applying the medical regulations, improving the integration, and by increasing our software performance. Next year, we are also planning to found a start-up and we have already decided on a name and a logo – so if you are interested in updates, please visit out Linkedin channel.”

Then Dr. Avci Pinar, of Ludwig Maximilian University Hospital, spoke on the subject of “Machine Learning-Assisted Prediction of Non-melanoma Skin Cancer in Ex Vivo Confocal Laser Scanning Microscopy”.

She detailed how the optical techniques can improve diagnosis of different types of cancerous tumors, which can often appear to be similar and therefore easily mistaken for other types, whether the basal cell cancers [more common] or squamous cell cancers [less common].

In her conclusion, Dr. Pinar quoted noted dermatologist Prof. Jonathan Rees of the University of Edinburgh, “who said of the diagnostic use of machines and algorithms, ‘we are better with them than without them’. But,” Dr Pinar said, “I would add that yes we are better with them but we should not rely on them – as with Google Maps, which can sometimes lead you back to where you started.”

Application-oriented products

The state of commercial medical spectral imaging was then described by Dr. Axel Kulcke of Diaspective Vision, which has been developing spectral camera solutions for medical applications since 2015. Dr. Kulcke explained, “With our application-oriented product solutions, we provide competent and flexible support for both clinical and preclinical applications.”

Prof. Jürgen Popp, of Leibniz-IPHT, described the latest developments in clinical multicontrast imaging for tissue diagnostics. He outlined the objectives of his group at the Leibniz Institute for Photonics Technologies in Jena.

“We are starting with classical histology but we want to move step-by-step to an in vivo digital optical histopathology by using light. This will be by starting ex vivo, but in the end we want to be doing everything in vivo.” He continued, “This means combining endoscopy with these multi-contrast imaging technologies. If you look at the typical spectroscopy techniques that are used today, they have certain advantages but also disadvantages.

Multi-parameter imaging

“Considering hyperspectral imaging or Coherent Anti-Stokes Raman Scattering, second harmonic generation, or two photon fluorescence, they differ in penetration depths, spatial resolution, molecular specificity and speed. Each method has some advantages and some disadvantages, so we say why not take [elements] from the different technologies, the best parts of them, and somehow combine them, which leads to our multi-modal imaging approach.”

Prof. Popp’s working group molecular imaging investigates new chemically sensitive linear and non-linear spectroscopic contrast mechanisms, laser technologies and detection techniques for multi-contrast and multi-parameter imaging of biological and biomedical target structures – such as pathogens and their antibiotic resistance, tumor cells, tissue samples, cell organelles, and marker molecules, such as drugs and organs. The group’s clinical focus is on infectious diseases and tumor diseases, as these diseases have a high medical need for early diagnosis and therapy.