DilAo - Project:

Prediction of thoracic aortic dilatation in different
predisposing pathologies

Dilatation of thoracic aorta considers “silent killer” because it rarely causes any symptoms until it ruptures. Imaging has an important role in the follow-up of aortic dilation. Currently anatomical magnetic resonance imaging (MRI) and computed tomography (CT) are used to measure aortic diameter which is further used to follow-up aortic dilation.  Aortic diameter only fails to predict upcoming speed or severity of aortic dilation.

4D flow MRI can be applied to measure blood flow characteristics and derived parameters in the thoracic aorta, which are hypothesized to predict aortic dilation. We use Siemens 1.5 T MAGNETOM Aera for 4D flow measurements and analyze and visualize data with CAAS MR 4D Flow 2.0 software. The main parameters which are under interest are peak flow velocity, peak flow, regurgitant fraction, flow displacement and wall shear stress.

There are some heritable genetic risk factors and mutations which can cause diseases, e.g. Marfan’s and Loeys-Dietz syndrome, which increase the risk of developing aortic dilatation. Marfan’s syndrome is a disorder of connective tissue, and it’s caused by different mutations on FBN1–gene.

The aim of this study is to find out predictive risk factors for aortic dilatation.

Streamlines of flow velocity in 4D Flow
MRI imaging.
Wall Shear Stress in thoracic aorta.

Study group


Group leader

Marja Hedman
MD, PhD, Adjunct Professor, Cardiologist
marja.hedman (at) kuh.fi

Department of Clinical Radiology
Diagnostic Imaging Center
Kuopio University Hospital
P.O. BOX 100
FIN-70029, Kuopio, Finland



Timo Liimatainen
PhD, Adjunct Professor, Physicist
timo.liimatainen (at) oulu.fi

Pekka Jaakkola
MD, PhD, Adjunct Professor, Heart and Thoracic Surgeon
pekka.jaakkola (at) kuh.fi

Hanna Matikka
MSc, PhD, Physicist
hanna.matikka (at) kuh.fi

Petri Saari
MD, PhD, Radiologist
petri.saari (at) kuh.fi

Tomi Laitinen
MD, PhD, Professor
Clinical Physiology and Nuclear Medicine
tomi.laitinen (at) kuh.fi

Ritva Vanninen
MD, PhD, Professor, Radiologist 
ritva.vanninen (at) kuh.fi

Doctoral students

Petteri Kauhanen / BM
Department of Clinical Radiology
petkau (at) student.uef.fi

Elina Kariniemi / MD
Department of Clinical Physiology and Nuclear Medicine
elina.kariniemi (at) kuh.fi

Teemu Kiljander / MD
Central Finland Central hospital, Department of Cardiology
teemu.kiljander (at) ksshp.fi



Seppo Ylä-Herttuala / MD, PhD, Professor
Department of Biotechnology and Molecular Medicine
A.I.Virtanen Institute, University of Eastern Finland

Juha Töyräs / PhD, Professor
Department of Applied Physics, BBC-group
University of Eastern Finland

Pirjo Mustonen / MD, PhD, Professor
JAMK, University of Applied Sciences, Institution of Information Technology
pirjo.mustonen (at) ksshp.fi

Matti Kurki, Dr. Tech., Head of Department
JAMK University of Applied Sciences, Industrial Engineering
matti.kurki (at) jamk.fi


Kauhanen SP, Hedman M, Kariniemi E, Jaakkola P, Vanninen R, Saari P, et al. Aortic dilatation associates with flow displacement and increased circumferential wall shear stress in patients without aortic stenosis: A prospective clinical study. J Magn Reson Imaging 2019 Jan 18.