Fig. (17).

40 year’s old female with fibromuscular dysplasia, irregularities with luminal narrowing of both ICAs (A, B) and left M1 (C) are present on CTA. Axial CTA shows diffuse concentric thickening of wall of ICAs with luminal narrowing (arrows on D). Fat saturated T1W images did not reveal any hyperintensity suggesting intramural hematoma (not shown here). Following steroid treatment, wall thickening of ICAs lessens and their luminal diameter gets increased comparing to the pretreatment appearances (arrows on E). Note is that multiple vessels and long segment involvement are suggestive of vasculitis.