Normalization of reduced functional connectivity after revascularization of asymptomatic carotid stenosis.
Fanny QuandtFelix FischerJulian SchröderMarlene HeinzeSimon S KessnerCaroline MalherbeRobert SchulzBastian ChengJens FiehlerChristian GerloffGötz ThomallaPublished in: Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism (2019)
Internal carotid artery stenosis is a risk factor for ischemic stroke. Even in the absence of visible structural brain changes, patients with asymptomatic stenosis are prone to cognitive impairment. On a neuronal level, it was suggested that stenosis may lead to disturbed functional brain connectivity. If so, carotid revascularization should have an effect on hypothesized brain network disturbances. We studied functional connectivity in a motor network by resting-state electroencephalography in 12 patients with high grade asymptomatic carotid stenosis before and after interventional or surgical revascularization as compared to 23 controls. In patients with stenosis, functional connectivity of neural oscillations was significantly decreased prior and improved returning to normal connectivity after revascularization. In a subgroup of patients, also studied by contrast perfusion magnetic resonance imaging, reduced connectivity was associated with decreased regional brain perfusion reflected by increased mean transit time in the middle cerebral artery borderzone. Cognitive testing revealed only minor differences between patients and controls. In summary, we identified oscillatory connectivity changes in patients with asymptomatic carotid stenosis correlating with regional hypoperfusion, which both normalized after revascularization. Hence, electrophysiological changes might be a reversible precursor preceding macroscopic structural brain damage and behavioral impairment in patients with asymptomatic carotid stenosis.
Keyphrases
- resting state
- functional connectivity
- middle cerebral artery
- internal carotid artery
- end stage renal disease
- magnetic resonance imaging
- percutaneous coronary intervention
- cognitive impairment
- coronary artery bypass grafting
- ejection fraction
- chronic kidney disease
- high grade
- peritoneal dialysis
- prognostic factors
- magnetic resonance
- oxidative stress
- contrast enhanced
- clinical trial
- atrial fibrillation
- single cell
- low grade
- multiple sclerosis
- high frequency
- white matter
- study protocol
- open label
- patient reported