THE EIS TECHNOLOGY Unique technology SciBase Electrical Impedance Spectroscopy (EIS), a patented technology developed over 20 years at Karolinska Institutet Stockholm, is applied to the skin as harmless electrical signals. EIS is sensitive to changes in cellular structure, cellular orientation, cell sizes and cell types – all of which are similar to those on which a histopathologist would base his or her diagnosis. This new methodology enhances information extraction from multi-depth spectra using an innovative non-invasive electrode system that facilitates precise data collection and analysis. How it works Skin tissues have different electrical properties under different medical conditions. Based on this, it is possible to identify a condition, such as malignant melanoma, using Nevisense’s unique EIS method. EIS is a measure of the overall resistance within the tissue at alternating currents of various frequencies. It is measured by applying an unnoticeable alternating potential between the bars on the tip of the probe. In order to cover the lesion in both width and depth, the measurement is performed in 10 permutations covering both shallow measurements between neighboring electrode bars as well as deeper measurements between more distant electrode bars. EIS reflects different cellular properties in different frequency regions. In general, EIS measurements at low frequencies are affected by the extracellular environment, whereas both the intra- and extracellular environments affect measurements at higher frequencies. The frequencies used by Nevisense (1 kHz – 2.5 MHz) relate to clinically relevant properties, such as composition of intra- and extracellular environments, cell shape and size, and cell membrane composition, all of which are similar to those used by histopathologists to diagnose skin cancer. Within seconds, an advanced algorithm is used to classify the lesion based on measurement data from both the lesion and the reference measurement. This classifier, developed in several iterations with data from multiple clinical studies, has proven to increase accuracy in melanoma detection in the pivotal study – the world’s largest clinical study of its kind.