Research at the Department of Diagnostic Radiology

Research activity at the Department of Diagnostic Radiology is wide. Here is a summary of some of the currently active projects. 

Development and validation of MRI methods suitable for prostate cancer detection and characterization

We are utilizing different intrinsic tissue MR contract mechanisms aiming to improve detection and characterization of prostate cancer.

Supervised by Prof. Hannu Aronen

MRI and DTI of preterm infants at term age

This research project is part of the PIPARI research lead by Professors Liisa Lehtonen, Leena Haataja and Docent Helena Lapinleimu from the Department of Pediatrics of Turku University Hospital. 

This work started in 2001, when all eligible preterm babies born under 32 gestational weeks or with birth weight less than 1500 grams were recruited to the project.

The study population consists of 232 preterm infants and 246 full term controls. The babies were imaged with magnetic resonance imaging and diffusion tensor imaging at term age using milk anesthesia. The babies were clinically carefully followed and the follow-up is still going clinically. 

Supervised by Prof. R. Parkkola

Read more
 

Molecular neuroimaging in reward: focus on obesity, addiction, and physical exercise

Positron emission tomography (PET) allows the non-invasive measurement of different proteins throughout the human body. PET is based on the use of specific molecular tracers that have been labeled with short-lived radioisotopes, and is therefore both highly specific and highly sensitive. PET is a functional imaging method that complements traditional structural imaging methods such as magnetic resonance imaging (MRI).

This research program is centered on imaging neurotransmitter receptors in reward functions, both in normally occuring reward (such as following physical exercise) and in disease with abnormal reward (such as obesity and addictive disorders). Animal studies show that multiple neurotransmitter receptors, such as dopamine, opioid, and cannabinoid receptors, contribute to neuronal circuits relevant for reward. We focus on in vivo imaging of these receptor across various disease groups and experimental settings. Other areas of interest include diagnostic neuroradiology and possibility of using novel molecular imaging biomarkers for the diagnosis of central nervous system pathologies such as malignant brain tumors.
 
Persons interested in completing a PhD degree or doing post-doctoral research are encouraged to apply for research positions. This research program maintains active collaborations with investigators.
 
Supervised by Docent J. Hirvonen

Main collaborators: Lauri Nummenmaa, Kari Kalliokoski, Pirjo Nuutila, Lauri Tuominen

MRI targeted prostate biopsy

We are performing MRI in patients with a clinical suspicion of prostate cancer.

Supervised by Prof. Hannu Aronen

MRI and DTI in dementia

Together with Professor Juha Rinne and the FINGER study group we are investigating the role of MRI in early detection of dementia. So far, PET imaging has been regarded as a golden standard in diagnostics of dementia. Alzheimer’s disease is the most common dementia in Finnish population. Mild Congnitive Impairment (MCI) is a precursor form of Alzheimer’s disease and some MCI patients progress rapidly to dementia, while others remain pretty stable for a long period. 

On conventional MR images the disease is usually in dementia phase, when medial temporal atrophy is recognized. In this work we are trying to find early MR markers for dementia to offer an alternative way to PET imaging in early dementia. Recent work on DTI had shown that white matter tract parameters show MCI when the conventional MR images still are normal. The same is found with resting state fMRI, which has shown that altered resting state fluctuation might be a good indicator of early dementia. We also study new imaging post-processing method, so called texture analysis in detection of early dementia.

Supervised by Prof. R. Parkkola

Development of prostate DWI

We are optimizing different acquisition schemes suitable for DWI of prostate.

Supervised by Prof. Hannu Aronen

MRI and Magnetic Resonance Spectroscopy (MRS) in metabolic disease

Together with the study groups of Professor Pirjo Nuutila and Docent Kirsi Virtanen, we are applicating MRS in metabolic research. 

MRS offers an easy and non-invasive method to investigate the fat and water composition of any given organ like liver or pancreas as well as bone marrow or heart muscle. This gives unique method to study the effect of for example training, medication or bariatric surgery to the fat composition of different organs. MRS gives a valuable tool to carbo-metabolic research and this work is now continuing in research of frail postmenopausal women.
 
Besides MRS, we are investigating the possibility to detect the brown adipose tissue of rodents and human with special techniques of MR. So far, PET imaging has been the golden standard of showing cold activated brown fat in humans. Our goal in the combined PET and MRI work is detect brown adipose tissue with MRI and to quantify is with MR images. We are working to resolve the best MR sequences to detect brown adipose tissue and to separate it from the white adipose tissue. The technique is demanding, but we have received promising results, which show that high amount of water in brown adipose tissue is associated with better insulin resistance and smaller waist circumference. 

Supervised by Prof. R. Parkkola

MR sequence development

Optimizing pulse sequences with the aim of improving tissue contract.
 
Supervised by Prof. Hannu Aronen

Metabolic imaging of bladder cancer

Development and validation of PET and MRI methods for the characterization of bladder cancer.

Supervised by Prof. Hannu Aronen

Whole body DWI

Optimization of whole body DWI for purposes of cancer staging.

Supervised by Prof. Hannu Aronen

Recent publications

Seasonal variation in the brain μ-opioid receptor availability (2021)

Journal of Neuroscience
Lihua Sun, Jing Tang, Heidi Liljenbäck, Aake Honkaniemi, Jenni Virta, Janne Isojärvi, Tomi Karjalainen, Tatu Kantonen, Pirjo Nuutila, Jarmo Hietala, Valtteri Kaasinen, Kari Kalliokoski, Jussi Hirvonen, Harry Scheinin, Semi Helin, Kim Eerola, Eriika Savontaus, Emrah Yatkin, Juha O Rinne, Anne Roivainen, Lauri Nummenmaa
(A1 Journal article – refereed)

Effect of Oral Moxifloxacin vs Intravenous Ertapenem Plus Oral Levofloxacin for Treatment of Uncomplicated Acute Appendicitis The APPAC II Randomized Clinical Trial (2021)

JAMA: Journal of the American Medical Association
Sippola S, Haijanen J, Grönroos J, Rautio T, Nordström P, Rantanen T, Pinta T, Ilves I, Mattila A, Rintala J, Löyttyniemi E, Hurme S, Tammilehto V, Marttila H, Meriläinen S, Laukkarinen J, Sävelä EL, Savolainen H, Sippola T, Aarnio M, Paajanen H, Salminen P
(A1 Journal article – refereed)

Foundations of human consciousness: Imaging the twilight zone (2021)

Journal of Neuroscience
Annalotta Scheinin, Oskari Kantonen, Michael Alkire, Jaakko Långsjö, Roosa Kallionpää, Kaike Kaisti, Linda Radek, Jarkko Johansson, Nils Sandman, Mikko Nyman, Mika Scheinin, Tero Vahlberg, Antti Revonsuo, Katja Valli, Harry Scheinin
(A1 Journal article – refereed)