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Updated: Aug 14, 2026

A Thrombotic Stroke Model Based On Transient Cerebral Hypoxia-ischemia
06:01

A Thrombotic Stroke Model Based On Transient Cerebral Hypoxia-ischemia

Published on: August 18, 2015

Cerebral microbleeds are common in ischemic stroke but rare in TIA

D J Werring1, L J Coward, N A Losseff

  • 1Stroke Research Group, Institute of Neurology, University College London, National Hospital for Neurology and Neurosurgery, London, UK.

Neurology
|December 29, 2005
PubMed
Abstract

Insights

Microbleeds are common in ischemic stroke but rare in transient ischemic attack (TIA). This difference is not explained by typical risk factors, impacting antithrombotic therapy safety and clinical trial design.

Area of Science:

  • Neurology
  • Radiology
  • Vascular Medicine

Background:

  • Gradient-echo MRI frequently detects microbleeds in stroke patients, indicating small artery disease and increased bleeding risk.
  • Antithrombotic treatments are common post-stroke/TIA, yet microbleed prevalence in TIA remains unstudied.
  • Microbleeds may predict hemorrhagic risk associated with antithrombotic therapies.

Purpose of the Study:

  • To investigate the prevalence of microbleeds in patients with ischemic stroke and transient ischemic attack (TIA).
  • To identify risk factors and pathophysiologic mechanisms associated with microbleeds in these patient groups.
  • To assess the clinical implications of microbleed detection for treatment and research.

Main Methods:

  • 129 consecutive patients with ischemic stroke or TIA underwent MRI (T2, FLAIR, gradient-echo).
  • Blinded observers quantified microbleeds and graded white matter T2 hyperintensities.
  • Patients with prior ischemic stroke were excluded from the TIA group.

Main Results:

  • Microbleeds were detected in 23% of ischemic stroke patients versus 2% of TIA patients (p < 0.001).
  • No significant differences in conventional risk factors or white matter disease severity between stroke and TIA groups.
  • Microbleed presence correlated with hypertension (81% vs 59%, p=0.04) and more severe white matter disease (p=0.003).

Conclusions:

  • Microbleeds are significantly more common in ischemic stroke than TIA, irrespective of vascular risk factors or white matter disease severity.
  • Findings impact the safety considerations for antithrombotic therapy and clinical trial design in stroke versus TIA.
  • Microbleeds may serve as a novel biomarker for severe microvascular pathology and heightened risk of cerebral infarction.

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