The ultrasonographic examination of the arteries supplying the brain can detect any deposits (arterial plaque) and calcifications of the artery walls. These risk factors are brought about through smoking, elevated cholesterol levels, high blood pressure, diabetes mellitus or an inherited predisposition. Symptomatic narrowing > 75% is treated using surgical or interventional (PTA/ stent) procedures. By systematically dealing with the risk factors, treatment can prevent or delay vascular stenosis and/or build-up in already existing regions of narrowing.