Skip to main content Accessibility help
  • Print publication year: 2011
  • Online publication date: July 2011

Chapter 20 - Cerebral microbleeds and thrombolysis

from Section 3 - Microbleeds in relation to specific populations, diseases and neurological symptoms


Cerebral amyloid angiopathy (CAA) occurs commonly in the elderly population. It results in thickening of the vessel wall, primarily in small arteries and arterioles of the leptomeninges and cerebral cortex. Primary intracerebral hemorrhage (ICH) in the elderly is the result of disease of the small cerebral vessels, in particular hypertensive vasculopathy or CAA. The CAA-related cerebral microbleeds (CMBs), like other types of microbleed, consist primarily of macrophages containing hemosiderin, a degraded form of ferritin. The most commonly employed criteria for diagnosis of CAA-related ICH are based on neuropathological examination or, more commonly, characteristic neuroimaging findings. Despite its high age-related prevalence, CAA has been difficult to detect non-invasively and is, likely to be underestimated in its effects on the aging process. The occurrence of CAA-related CMBs has emerged as the most useful diagnostic marker for CAA in clinical practice and investigation.


1. NINDS rt-PA Stroke Group. Tissue plasminogen activator for acute ischemic stroke. New Engl J Med 1995;333:1581–7.
2. FurlanA, HigashidaR, WechslerLet al. Intra-arterial prourokinase for acute ischemic stroke. The Proact II study: a randomized controlled trial. Prolyse in acute cerebral thromboembolism. JAMA 1999;282:2003–11.
3. HackeW, KasteM, BluhmkiEet al. Thrombolysis with alteplase 3 to 4.5 hours after acute ischemic stroke. N Engl J Med 2008;359:1317–29.
4. WahlgrenN, AhmedN, DavalosAet al. Thrombolysis with alteplase 3–4.5 h after acute ischaemic stroke (SITS-ISTR): an observational study. Lancet 2008;372:1303–9.
5. KidwellCS, SaverJL, VillablancaJPet al. Magnetic resonance imaging detection of CMBs before thrombolysis: an emerging application. Stroke 2002;33:95–8.
6. ConfortoAB, LucatoLT, Leite CdaCet al. Cerebral CMBs and intravenous thrombolysis: case report. Arq Neuropsiquiatr 2006;64:855–7.
7. ChalelaJA, KangDW, WarachS. Multiple cerebral CMBs: MRI marker of a diffuse hemorrhage-prone state. J Neuroimaging 2004;14:54–7.
8. KangDW, ChalelaJA, DunnW, WarachS. MRI screening before standard tissue plasminogen activator therapy is feasible and safe. Stroke 2005;36:1939–43.
9. NighoghossianN, HermierM, AdeleinePet al. Old CMBs are a potential risk factor for cerebral bleeding after ischemic stroke: a gradient-echo T2*-weighted brain MRI study. Stroke 2002;33:735–42.
10. DerexL, NighoghossianN, HermierMet al. Thrombolysis for ischemic stroke in patients with old CMBs on pretreatment MRI. Cerebrovasc Dis 2004;17:238–41.
11. FiehlerJ, SiemonsenS, ThomallaG, IlliesT, KucinskiT. Combination of T2*w and FLAIR abnormalities for the prediction of parenchymal hematoma following thrombolytic therapy in 100 stroke patients. J Neuroimaging 2009;19:311–16.
12. KakudaW, ThijsVN, LansbergMGet al. Clinical importance of CMBs in patients receiving iv thrombolysis. Neurology 2005;65:1175–8.
13. FiehlerJ, AlbersGW, BoulangerJMet al. Bleeding risk analysis in stroke imaging before thrombolysis (BRASIL): Pooled analysis of T2*-weighted magnetic resonance imaging data from 570 patients. Stroke 2007;38:2738–44.
14. BarronHV, RundleAC, GoreJM, GurwitzJH, PenneyJ. Intracranial hemorrhage rates and effect of immediate beta-blocker use in patients with acute myocardial infarction treated with tissue plasminogen activator. Participants in the National Registry of Myocardial Infarction-2. Am J Cardiol 2000;85:294–8.
15. McCarronMO, NicollJA. Cerebral amyloid angiopathy and thrombolysis-related intracerebral haemorrhage. Lancet Neurol 2004;3:484–92.
16. WinklerDT, BondolfiL, HerzigMCet al. Spontaneous hemorrhagic stroke in a mouse model of cerebral amyloid angiopathy. J Neurosci 2001;21:1619–27.
17. BroderickJ, LuM, JacksonCet al. Apolipoprotein e phenotype and the efficacy of intravenous tissue plasminogen activator in acute ischemic stroke. Ann Neurol 2001;49:736–44.