Changes in visibility of intracranial arteries on MRA with normal ageing

We investigated age-related changes in the visibility of intracranial arter ies on magnetic resonance angiography (MRA) and the influence of risk facto rs for stroke. We studied 230 adult patients without specific neurological deficits. MRA was performed using the three-dimensional time-of-flight tech nique with a spoiled gradient-recalled acquisition sequence. We classified internal carotid artery (IC) and the horizontal (M1) and distal (beyond M2) middle cerebral segments into 4 grades. Linear regression revealed a signi ficant negative relation between age and the quality of demonstration on MR A. For IC and M1, the score was significantly lower in subjects with risk f actors than in those without. The distal MCA was poorly seen in patients wi thout a history of hypertension or lacunar infarcts. A marked correlation w as observed between visibility and age patients with no history of hyperten sion, diabetes mellitus and hyperlipidaemia. We suggest that atheroscleroti c change and decline in flow velocity with normal ageing are factors leadin g to decreased visibility on MRA.