OCT has already long since been used in ophthalmology to investigate the retina, and also in dermatology. However so far, it has not been possible to take a detailed enough “look” under the skin to detect the early stages of cancer or the progression of skin cancer. This has now been made possible thanks to new laser technology that was developed in collaboration with the Ludwig Maximilian University in Munich. An innovative illumination method has also been developed that allows the skin to be “penetrated” more effectively.
This technology has a 500 nanometre higher wavelength at 1,300 nanometres and allows 440,000 depth profiles to be recorded per second compared to 20,000 to 60,000 using normal optical coherence tomography. The higher wavelength is needed in order to be able to penetrate deeper into the skin tissue.
Says Leitgeb: “The higher speed is necessary so that we do not lose contrast while we are imaging the details due to the patient moving. It gives us a detailed picture of the perfusion of the blood and the structure of vessels. This is therefore the first time anywhere in the world that we have been able to achieve this degree of detail to image the vascular system of human skin cancers.”
Understanding the tumour better
The technology also sheds light on how existing tumours are nourished. “If we are able to understand this process better, we will be able to fight it more effectively,” says the MedUni researcher. Pre-stages of tumours in the skin can also be made visible and without any need for painful procedures (biopsy).
Says Leitgeb: “With this new method, we therefore have a new option for the development of new, more targeted therapies. We hope that we will be able to develop a scan that dermatologists can use to discover skin cancer and its early stages early anywhere on the body and therefore also be able to treat it at an early stage.”
The initial results of the study have now been published in the professional journal Biomedical Optics Express. A clinical study that is currently ongoing at the MedUni Vienna is re-evaluating the results, while scientists in Vienna and Munich are also working on optimising the technology used further.
Service: Biomedical Optics Express
“In situ structural and microangiographic assessment of human skin lesions with high-speed OCT”. Cedric Blatter, Jessika Weingast, Aneesh Alex, Branislav Grajciar, Wolfgang Wieser, Wolfgang Drexler, Robert Huber, Rainer A. Leitgeb. Biomedical Optics Express, Vol. 3, Issue 10, pp. 2636-2646 (2012).