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Published on: September 25, 2016
New microbleeds after thrombolysis: contiguous thin-slice 3T MRI
Shenqiang Yan1, Yi Chen, Xuting Zhang
1Department of Neurology (SY, YC, XZ, ML), Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China; and Los Angeles Stroke Center (DSL), University of California, Los Angeles, California.
Abstract:
We aimed to determine the frequency of new microbleeds after intravenous thrombolysis using contiguous thin-slice 3T magnetic resonance imaging. We retrospectively examined clinical and imaging data from 121 consecutive acute ischemic stroke patients who underwent magnetic resonance imaging before and 24 hours after intravenous thrombolysis. Of the included patients, 44 (36.4%) were women, with a median age of 69 years (range, 35-94 years). A total of 363 baseline microbleeds were observed in 57 patients and 8 new microbleeds in 6 patients. Multiple regression analysis indicated that baseline infarct volume (odds ratio, 1.556/10 mL; 95% CI, 1.017-2.379; P = 0.04) and systolic blood pressure (odds ratio, 1.956/10 mm Hg; 95% CI, 1.056-3.622; P = 0.03), but not the presence of baseline microbleeds, were independently associated with new microbleeds. The frequency of neither symptomatic intracranial hemorrhage nor remote hemorrhage or any hemorrhagic transformation was different between patients with and without new microbleeds (0.0% vs 1.7%, P > 0.99; 0.0% vs 1.7%, P > 0.99; 50.0% vs 28.7%, P =0.36). New microbleeds developed rapidly 24 hours after intravenous thrombolysis. The significance of these new microbleeds and their effect on cognitive and functional outcome merits further investigation.
Insights
New microbleeds can appear within 24 hours after intravenous thrombolysis for acute ischemic stroke. Baseline infarct volume and systolic blood pressure predict their development, not prior microbleeds.
Area of Science:
- Neurology
- Radiology
- Cardiology
Background:
- Intravenous thrombolysis is a critical treatment for acute ischemic stroke.
- Microbleeds are common in stroke patients and may influence treatment decisions.
- Understanding the incidence and predictors of new microbleeds post-thrombolysis is crucial.
Purpose of the Study:
- To determine the frequency of new microbleeds following intravenous thrombolysis.
- To identify factors associated with the development of new microbleeds.
Main Methods:
- Retrospective analysis of 121 acute ischemic stroke patients.
- Sequential 3T MRI scans (pre-treatment and 24 hours post-treatment).
- Statistical analysis including multiple regression to identify predictors.
Main Results:
- New microbleeds were observed in 6 patients (4.9%) within 24 hours post-thrombolysis.
- Baseline infarct volume and systolic blood pressure were independently associated with new microbleeds.
- The presence of baseline microbleeds did not predict new microbleeds.
Conclusions:
- New microbleeds can rapidly develop after intravenous thrombolysis.
- Infarct size and blood pressure are key predictors of new microbleed formation.
- Further research is needed to understand the clinical significance of these early post-treatment microbleeds.
