Myllylä Group

Tailored Medical Technology

Myllylä group focuses on developing and exploiting state-of-the-art multimodal technology to provide new tools and methods for medical use. Currently, our wearable techniques enable recording simultaneously brain’s hydro-, hemo- and electrophysiological dynamics, while continuously monitoring cardiovascular, blood pressure and respiratory signals. The main technologies we work in are functional near-infrared spectroscopy (fNIRS), diffuse correlation spectroscopy (DCS), ultrasound, photo-acoustic and capacitive imaging and a variety of multimodal wearable sensors. These we can combine with existing medical imaging technologies. Our novel technology can be utilized in medical and translational research and therapies, on a wide range of topics. For instance, in diagnostics of neurodegenerative diseases (dementia, Parkinson’s disease), brain injury (stroke, edema, cerebral hemorrhage) and in assessment of pain and sleep quality.

Our highly multidisciplinary research brings together researchers worldwide with expertise in medical instrumentation, sensor technology and signal processing, to work side by side with medical physics, clinician and biomolecular scientists. Myllylä group is divided into two Research Units, where in the Optoelectronics and Measurement Techniques Research Unit, in Faculty of Information Technology and Electrical Engineering, the activities focus on Biomedical Sensors and Measurement Systems design and research to support and co-work in our research in MIPT, where we have the following focus areas.

Assessment of neurohydrodynamics and blood brain barrier (BBB) permeability

For brain monitoring, optics-based imaging techniques, being safe and noninvasive, hold a high potential. In particular, fNIRS offers a portable solution for long-term monitoring of the brain, also during sleep. One advantage of fNIRS is its ability to simultaneously measure changes in the concentration of cerebral oxyhaemoglobin, deoxyhaemoglobin, blood volume. At the moment, we are further developing the fNIRS technique for sensing glymphatic system and BBB opening.

The term glymphatic system was first used in 2013 to describe the pathway for removing protein waste products from the central nervous system. Connected with the complex organization of dural lymphatic vessels, the glymphatic system and fluctuations in CSF have attracted considerable interest in recent years, particularly in relation to origins of dementia. Further, findings on dementia also indicate that increasing of BBB permeability can facilitate the removal of the protein accumulations and eventually reverse memory loss. In this highly interesting research topic, we closely work in an Academy of Finland consortium with Kiviniemi (OFNI) Group, Eklund Group in Biocenter Oulu and Alitalo Group in University of Helsinki.

Wearable and continuous cardiovascular and brain monitoring

Brain studies can get a great advantage of the exciting possibility of combining data from different wearable techniques. For instance, it enables us to investigate causality between complex neurological mechanisms and variables - increased neuronal activity produces a metabolic demand for glucose and oxygen, raising cerebral blood flow to the active brain region. Being impossible to study accurately by any single imaging modality, a process of this type requires simultaneous use of different imaging techniques.

We aim to measure accurately and simultaneously such physiological parameters as heart rate, blood pressure and blood flow, changes in respiration and end-tidal carbon dioxide levels as well as shifts in blood flow distribution in the human body, also combined with neuroimaging.

Integrating macro and microscale imaging techniques

To better understand physiological signals recorded in the macro-scale, we gather information simultaneously in the micro-scale, with scientists having the expertise particularly in vascular imaging and advanced microscopy. To this end, together with Kiviniemi and Eklund Groups, we are developing a scalable monitoring concept that enables monitoring physiological signals to investigate macro-scale effects in humans and rodents. In addition, the rodent setup includes different micro-scale imaging techniques, such as photoacoustic imaging, and the possibility to use biomarkers and perform quantitative microscopic tissue analyses. This allows us to study correlations between data recorded in micro and macro scale. Importantly, it also lets us validate and optimize new macroscopic sensing and imaging techniques for human use.

Monitoring technology for clinical therapies and procedures

Tailored radiotherapy using novel optics-based technology: In this Academy of Finland project, our goal is to provide a new method for monitoring tumour radiotherapy. Sensing cerebral dynamics, free water and oxygen radicals during radiotherapy could improve the effectiveness and safety of the radiation therapy when the concentration of the detected radicals correlate with the power of radiotherapy.

LightOpsy: In this TUTLI project, together with Miika Nieminen group and Heikki Nieminen group in Aalto University, we developed multifunctional probe to be embedded inside a biopsy needle. The probe will aid interventional radiologists in the biopsy acquisition process.

The research is currently funded by Academy of Finland, Infotech Oulu, Business Finland and EDUFI.