Doctoral defence: Nigul Ilves "Brain plasticity and network reorganization in children with perinatal stroke: a functional magnetic resonance imaging study"

On 1 November at 14:00 Nigul Ilves will defend her doctoral thesis "Brain plasticity and network reorganization in children with perinatal stroke: a functional magnetic resonance imaging study".

Supervisors:
Pilvi Ilves, Univesrity of Tartu
Rael Laugesaar, University of Tartu
Mairi Männamaa, Tartu University Clinic

Opponent:
Helen Carlson, University of Calgary (Canada)

Summary
Stroke can occur during the entire lifetime and is probably underdiagnosed in children. In perinatal period the risk of stroke is especially high, about 1:1000 live births. Perinatal stroke may lead to various motor and cognitive impairments and epilepsy. Perinatal stroke causes lifelong physical, mental and emotional disabilities and social burden not only to children, but also to their families along with an economic burden to the society.

Perinatal stroke is a heterogonous condition, with different brain lesions depending on the vascular type of stroke leading to different outcomes. Children’s brain is plastic and able to reorganize and at least partly compensate for damage after stroke. However, the knowledge of perinatal stroke is still limited due to the low prevalence and inherent heterogeneity of damage.

The aim of the study was to investigate brain’s ability to reorganize in different vascular types of perinatal stroke compared to healthy controls and to evaluate how it affects the motor, cognitive and language outcomes. Various radiological markers for predicting motor, cognitive and language outcome in children with perinatal stroke were identified using functional magnetic resonance imaging and volumetric image analysis.

The study showed that motor, cognitive and language outcomes in children with perinatal stroke correlates with vascular type and extent of stroke lesion. The brain’s plasticity and reorganization abilities were shown to only minimize the negative effect of large stroke lesions, but not to ensure entirely normal outcome.

The knowledge of brain plasticity and reorganization in perinatal stroke children can be generalized to cases involving other focal brain damages, like trauma, tumors and epilepsy. The study accentuates the importance of radiological investigation of children with perinatal stroke and enhances the value of radiological evaluation.