Figure 4

Case 3 inflammatory CAA: A 71-year-old man developed two episodes of left-sided paraesthesia and twitching, consistent with focal seizure. He had a background of subacute confusion. Based on the imaging findings, he underwent brain and leptomeningeal biopsies, showing scattered small-sized and medium-sized vessels with patent lumina and thickened walls. Congo red staining in these vessels showed positive staining with apple-green birefringence under polarised light, in keeping with inflammatory CAA. His symptoms responded well to levetiracetam and intravenous methylprednisolone but he relapsed 16 months later. Again, he responded well to 3 days of intravenous methylprednisolone and subsequently weaning dose of prednisolone. He has remained asymptomatic, but MR scanning with SWI sequence showed progression of superficial siderosis and microbleeds. (A) Convexity SAH with hypodensity parietal cortical and subcortical area on CT scan of the head (white arrow). (B) Corresponding MR brain scan T2/FLAIR convexity SAH (white arrow) and oedematous mass lesion (red arrow). (C) SWI superficial siderosis and microbleeds (white arrow). (D) Resolution of right parietal T2/FLAIR lesion but new right frontal T2/FLAIR (red arrow). (E) Corresponding T1 hypointensity with contrast enhancement (red circle). (F) Persisting superficial siderosis and microbleeds perhaps with some progression (white arrow). (G) Resolution of both the frontal and persisting resolution of right parietal oedematous T2/FLAIR lesion. (H) No further T1 contrast enhancement. (I) Progression of superficial siderosis and microbleeds (white arrow). CAA, cerebral amyloid angiopathy; SWI, susceptibility-weighted imaging; FLAIR, fluid-attenuated inversion recovery; SAH, subarachnoid haemorrhage.