Professor Dr Vasilis Ntziachristos

Research Priorities: Biomedical engineering, imaging and sensing, optoacoustics, computational methods, clinical translation
Vasilis Ntziachristos is a Greek electrical engineer who specialises in imaging and its use in medicine. He focuses on developing non-invasive optical and optoacoustic imaging which, combined with sensors and data processing methods, can help diagnose diseases at their earliest stages and thus improve patients’ chances of recovery.
Imaging plays a key role in the diagnosis and management of a wide range of diseases. Methods such as x-ray, ultrasound, and magnetic resonance imaging (MRI) have revolutionised medicine, but reveal limitations when dealing with certain issues. Ultrasound, for example, offers only low-resolution images of different structure densities, and visualises blood flow in larger vessels by means of Doppler ultrasound, but does not provide information about other biological properties of the tissue being examined. Purely optical procedures based on light reflection or dispersal only penetrate to less than one millimetre below the surface due to major optical dispersal in the skin tissue.
To overcome these challenges, Vasilis Ntziachristos and his team developed Raster-Scan-Optoacoustic Mesoscopy (RSOM), a technology that delivers images with a resonance level between macroscopy and microscopy. RSOM enables a particularly detailed depiction of biological structures and functions in and beneath the skin. The RSOM is based on combining light and sound, a phenomenon known as optoacoustics and which gives this technology its name. It involves directing brief, low-energy light pulses at the skin, which results in a minimal warming – usually below one degree Celsius – of the tissue. This warming causes a brief stretching and then contraction of the tissue, generating ultrasound waves.
Optoacoustic imaging is an innovative, hybrid modality that combines the advantages of acoustics and optics. The ultrasonic signals generated by the absorption of light can be utilised for imaging that offers both high optical contrast and high spatial resolution. The sound waves spread through the tissue and are recorded by ultrasound transducers on the surface. By processing and converting these sound waves detailed, three-dimensional images of the area under investigation can be created. With support from modern computing methods and artificial intelligence, the procedure offers new possibilities for prevention and precision medicine.
Combining light and sound not only makes RSOM affordable, it also enables miniaturisation of the technology. This mean the technology can be used not just in hospitals, but also in doctors’ practices and potentially even in patients’ homes. 
Vasilis Ntziachristos focuses on both developing new procedures and practical applications of optoacoustic technology. For example, he has already established several spin-offs in the area of fluorescent and optoacoustic imaging for biomedical applications.