Artery damage, coloured MRA scan sequence. Magnetic resonance angiography MRA scans showing artery damage of a male 23_year_old motorcycle crash patient. Narrowing of the proximal right internal carotid artery seen at the start of the clip on the left side continues throughout its length and is the result of damage to the wall of the vessel. The muscular layers within the arterial wall get damaged and arterial blood is forced between the muscular lining which causes the narrowing. For scans of each side separately, damaged and undamaged, see clip numbers K003 4497 and K003 4500. For original see clip number K003 4410.