Klinisk institutt 1

Midtveisevaluering - Sander Johan Aarli

Midtveisevaluering for ph.d.-graden ved Universitetet i Bergen for kandidat Sander Johan Aarli

Sander Johan Aarli er tilknyttet Klinisk institutt 1. Veiledere er Annette Fromm, Lars Thomassen, Nicola Logallo og Christopher Kvistad.


The Norwegian Microemboli in Acute Stroke Study (NOR-MASS)


Ischemic stroke is a complex and heterogeneous disease. Despite extensive routine diagnostics, the cause of stroke remains unknown in 25-40% of patients. Cerebral emboli are presumed to cause a substantial proportion of strokes of undetermined etiology. Transcranial ultrasound monitoring (TCDM) is a non-invasive method for detecting circulating cerebral microemboli. New, ambulatory equipment allows for prolonged monitoring sessions, with less patient discomfort, and may simplify the implementation of TCDM in standard diagnostics.

NOR-MASS is a clinical observational study investigating the benefit of TCDM in the acute phase of ischemic stroke. Patients with acute ischemic stroke of all etiologies are included and examined with TCDM in addition to the standard diagnostic work-up. TCDM is performed <24 hours after symptom onset and repeated the next two days. The aim of the study is to assess the prevalence and time course of microemboli in the acute phase of stroke and explore the association between microemboli and risk of stroke recurrence. Furthermore, we aim to evaluate the expected utility of TCDM in standard diagnostics.

The first paper is based on a sub-study where we assessed the persistence of microembolic signals after ultrasound contrast infusion in healthy volunteers, using TCDM. In a second sub-study, we will investigate the association between cerebral microemboli and plaque neovascularization in patients with carotid artery atherosclerosis. The third paper will present the main data from NOR-MASS.