Microbleeds Versus Macrobleeds Evidence for Distinct Entities

• Published in: Stroke (1970) 2009-07, Vol.40 (7), p.2382-2386
• Main Authors: GREENBERG, Steven M, KAVEER NANDIGAM, R. N, DELGADO, Pilar, BETENSKY, Rebecca A, ROSAND, Jonathan, VISWANATHAN, Anand, FROSCH, Matthew P, SMITH, Eric E
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Arterioles - pathology; Biological and medical sciences; Cerebral Amyloid Angiopathy - complications; Cerebral Arteries - pathology; Cerebral Hemorrhage - diagnosis; Cerebral Hemorrhage - etiology; Diagnosis, Differential; Female; Humans; Magnetic Resonance Imaging; Male; Medical sciences; Neurology; Neuropharmacology; Neurotransmitters. Neurotransmission. Receptors; Pharmacology. Drug treatments; Retrospective Studies; Serotoninergic system; Vascular diseases and vascular malformations of the nervous system
• ISSN: 0039-2499; 1524-4628
• DOI: 10.1161/STROKEAHA.109.548974

Small, asymptomatic microbleeds commonly accompany larger symptomatic macrobleeds. It is unclear whether microbleeds and macrobleeds represent arbitrary categories within a single continuum versus truly distinct events with separate pathophysiologies. We performed 2 complementary retrospective analyses. In a radiographic analysis, we measured and plotted the volumes of all hemorrhagic lesions detected by gradient-echo MRI among 46 consecutive patients with symptomatic primary lobar intracerebral hemorrhage diagnosed as probable or possible cerebral amyloid angiopathy. In a second neuropathologic analysis, we performed blinded qualitative and quantitative examinations of amyloid-positive vessel segments in 6 autopsied subjects whose MRI scans demonstrated particularly high microbleed counts (>50 microbleeds on MRI, n=3) or low microbleed counts (