Medical physics 

Research is focused in the development of novel methods and applications for medical imaging and therapy.  The research is being conducted in by a large group of dedicated researchers consisting of important collaborators from UH, HUCH and STUK.  Medical Physics group published 13 per review papers in 2014.

Altogether medical physics researchers had presentations in the following international conferences: 1) Physics Days, Tampere;   2) 10th Symposium of the Scandinavian Japanese Radiological Society & 13th Nordic Japan PACS Symposium,  Turku; 3) Conference on Radiation Protection in Medicine, Varna; 4) International Congress on Neutron Capture Therapy, Helsinki;  5) Annual EANM Congress,  Göteborg; 6) the ESR Annual Leadership Meeting,   Firenze; 7) NACP CT-course - Evolving new technology in CT: Dosimetry, Quality Assurance, Optimization,  Helsinki; 8) 18th ISRRT World congress, Helsinki;  9) Quality Assurance of Ultrasound, Stockholm; 10) RSNA, Chicago.

The biannual International congress on Neutron Capture Therapy was organized and hosted by three major Finnish institutions in June. HUCH, UH and VTT organized collectively the conference and helped the most forefront research in the field of Neutron Therapy to advance even further.  The organization team itself is also active within the community and had several scientific presentation during the conference. The conference talks have partially been based on the results obtained from still ongoing research project at the FiR1 research reactor. The questions involve inaccuracies of nuclear databases, which lead to inconsistent simulation results, or alternative dosimeter techniques that could be used in medical imaging and treatment procedures.

In new promising radiotherapies like radionuclide therapies biological effects of the radiation have to be studied on cellular scale. The aim of the research is to develop more realistic 3D cell cluster models and dosimeter software for the cellular and sub-cellular dosimeter and to study the significance of the models for the analysis of the biological effects of the radiation. State-of-the-art 3D microscope technology is used to generate the necessary data for the models.

177Lu post-therapy activity distribution can be imaged using a calibrated SPECT/CT system and physically accurate dose distribution can be simulated from the images using Monte Carlo (MC) simulations. Simulating electron dose using MC is time consuming and is not typically feasible in clinical practice.  Iodine-123-FP-CIT is clinically used in the diagnosis of Parkinson's disease. The kinetics of FP-CIT into dopamine transporters, which are located in the striatum, have been examined in vivo in humans but little in vivo in rodents.   

Direct radioisotope cystography and voiding cystourethrography are studies to detect and follow-up vesicouretal reflux. Due to the increased radiosensitivity of children, compared to adults, the estimation of the radiological risk is particularly important. 

The research on CT optimization were focused on the effect of patient miscentering on patient dose and image quality; utilizing a model-based iterative reconstruction to limit radiation dose in CT for craniosynostosis; determining fetal radiation doses in CT; studying lens doses in head CT with different CT optimization methods.

Simultaneous EEG/fMRI and Diffusion Tensor Imaging (DTI) project aims to develop simultaneous EEG/fMRI to a clinical tool for presurgical evaluation of patients with epilepsy. After the extensive exploration of safety and quality assurance issues in simultaneous EEG/fMRI, the current focus has been on improving the artifact correction methods and modelling of the haemodynamic response. In Diffusion Tensor Imaging (DTI) the main focus has been on developing clinically feasible analysis methods for tractography. Diffusion kurtosis imaging (DKI) is a new interesting application of DTI. Sequences and analysis methods have been developed for DKI, including multiband kurtosis sequences for whole brain imaging and conventional diffusion kurtosis imaging of cervical spine.

The safety of MRI in patients with cardiac pacemakers was studied. Furthermore, the role of cardiac MRI (e.g. T1 mapping) in the diagnostics was studied in the patients having PRKAG2 gene mutation. Quality assurance protocols have been studied for body diffusion weighted MRI.

In the field of ultrasound technology, the focus was shifted to technical quality assurance of Doppler ultrasound. The main effort was concentrated on developing a reliable flow phantom that can form a base for further research in the field.

The use of navigated transcranial magnetic stimulation (nTMS) technique in speech mappings was improved by accompanying it with semi-automated voice onset detection.

The work on medical image processing has focused on developing and providing advanced computational methods and tools for imaging based research, clinical applications and quality control. This includes detection, localization and quantification of disease related changes in anatomy and function, e.g. heart volumetry and voxel based morphometry of the human brain. Tools for visualization and localization of intracranial EEG electrodes and epileptogenic areas are being developed.  Ongoing adoption of open source software has provided new tools and platforms for method development and research.