Our work is cross disciplinary and proceeds along parallel but interactive tracks in the following areas:
Deep Brain Stimulation (DBS)
Deep Brain Stimulation includes studies of mechanism of action by combining computer simulation, physiological measurements, imaging and clinical evaluations. Disorders of interest are Parkinson’s disease, essential tremor, and new indications and targets were DBS is introduced.
Fluorescence techniques for brain tumor resection
A portable system for on-line induced 5-ALA fluorescence is evaluated during brain tumor resection and biopsies. Fluorescence is compared with intra-operative MRI, histology and microscopy. Fluorescence guidance has also been introduced for pediatric brain tumor surgery. As a next step a system for Raman spectroscopy will be implemented.
Optical intracerebral navigation
Laser Doppler flowmetry and reflective spectroscopy are adapted for use during stereotactic DBS implantations and biopsies. Optical trajectories are defined for DBS targets, fundamental aspects of light interaction investigated and a “vessel warning” feature is explored.
Brain microcirculation is studied with e.g. Laser Doppler flowmetry (LDF) and by extracting chromophores, e.g. Hb and Hb02, from reflectance spectra. The LDF method has been adapted for intraoperative measurements during DBS-implantations, open tumor surgery and for on-line monitoring in neurointensive care.
Patient-specific modelling and simulation of DBS
Software for finite element method (FEM) modelling, simulation and visualization of the electric field around DBS electrodes has been developed. It is used with clinical evaluations of movement in Parkinson’s disease and essential tremor and is now introduced for new symptoms, brain targets and lead designs.
Neuron modelling is performed with software and physical constructions. Software models are combined with FEM models of DBS lead designs for increased knowledge of volume tissue activated. The Paxon, a physical axon model is designed as a test bench for electrodes commonly used in health care.
Sampling of neuroactive substances parallel to DBS implantations can be performed with microdialysis. Patient-specific FEM models stimulate the tissue volume of influence associated with microdialysis catheters placed in basal ganglia nuclei and DBS leads.