CFIN researcher, MD Thorbjørn Søndergaard Engedal is defending his PhD thesis on: "Capillary Transit Time Heterogeneity in Acute and Chronic Neurovascular Disease"

2017.04.24 | Henriette Blæsild Vuust

Capillary transit time heterogeneity in acute and chronic neurovascular disease – an MRI investigation of blood flow in the smallest blood vessels of the brain.

A new PhD project from Aarhus University, Health, investigates the relation between disturbed blood flow in the smallest blood vessels of the brain and the evolution of tissue damage and symptoms in acute ischemic stroke and in chronic small vessel disease. The study is the first to quantify the severity of capillary flow disturbance and to interpret this in relation to its effect on oxygen availability in patients suffering an ischemic stroke. The project was carried out by Thorbjørn S. Engedal, who is defending his dissertation on 4/5-2017.

In humans, delivery of nutrients, including the exchange of oxygen and carbon dioxide, takes place in the smallest blood vessels, the capillaries. Previous studies have shown that not only the volume of blood supply to the tissue, but also the quality of its distribution between individual capillaries, influence oxygen availability. In case of a stroke caused by a blood clot in a major cerebral artery, gradual capillary failure is observed in the blood-deprived tissue. This phenomenon could explain the loss of viable tissue, observed in the hours following symptom onset, if the blood clot is not removed.

The current PhD project shows how the degree of capillary failure can be estimated using perfusion MRI, and evaluates its relation to subsequent tissue damage. A perfusion MRI scan can be readily acquired in an emergency setting, and thus has the potential to identify patients, who will benefit from treatment. Additionally, the study provides substantial insights into the pathogenesis of the disease. In patients suffering hereditary, small vessel disease the study showed close correlation between the severity of capillary flow disturbance and progressive nature of the disease. In time, these findings may improve diagnostic and treatment options for these common and severe diseases.

The defense is public and takes place on Thursday 4 May, 2017 at 14.00 in Building 10, 8th floor, Aarhus University Hospital, Nørrebrogade 44.

ALL ARE WELCOME.

For more information, please contact PhD student Thorbjørn S. Engedal, 
Email: tsengedal@gmail.com, 
Phone: +45 2829 3053.