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Critical Illness-Associated Cerebral Microbleeds
Evgenia M Fanou1, Jonathan M Coutinho1, Patrick Shannon1
1From the Department of Medical Imaging (E.M.F., J.M.C., D.M.M.), Department of Pathology (T.-R.K.), and Interdepartmental Division of Critical Care Medicine (M.E.W.), University Health Network, Toronto, Ontario, Canada; Department of Pathology, Mount Sinai Hospital, Toronto, Ontario, Canada (P.S.); Department of Vascular Medicine (M.M.L.) and Department of Neurology (J.M.C.), Academic Medical Center, University of Amsterdam, The Netherlands; Department of Medical Imaging, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada (R.I.A.).
Background And Purpose:
Cerebral microbleeds (petechial hemorrhages) are a well-known consequence of cerebral amyloid angiopathy and chronic hypertension among other causes. We report 12 patients with a clinically and radiologically distinct microbleed phenomenon in the cerebral white matter.
Methods:
These patients were assessed at the University Health Network (Toronto, Canada) between 2004 and 2014.
Results:
Median age was 40 years (range, 27-63 years), and 7 out of 12 patients were women. All patients had brain magnetic resonance imaging during or immediately after an intensive care unit admission. All patients had respiratory failure, 11 out of 12 received mechanical ventilation, and 3 out of 12 received extracorporeal life support. Magnetic resonance imaging in all 12 patients showed extensive microbleeds, diffusely involving the juxtacortical white matter and corpus callosum but sparing the cortex, deep and periventricular white matter, basal ganglia, and thalami. Several patients also had internal capsule or posterior fossa involvement.
Conclusions:
We have described a distinct microbleed phenomenon in the cerebral white matter of patients with critical illness. The specific cause of the microbleeds is unclear, but the pathogenesis may involve hypoxemia as the microbleeds are similar to those described with high-altitude exposure.
Insights
This study describes a unique cerebral microbleed pattern in critically ill patients, distinct from typical causes like hypertension. The findings suggest a potential link to hypoxemia in critical illness.
Area of Science:
- Neurology
- Radiology
- Critical Care Medicine
Background:
- Cerebral microbleeds are often linked to conditions such as cerebral amyloid angiopathy and hypertension.
- A distinct pattern of microbleeds in the cerebral white matter was observed in 12 patients.
Purpose of the Study:
- To characterize a clinically and radiologically distinct microbleed phenomenon in the cerebral white matter.
- To investigate the potential causes and implications of this specific microbleed pattern.
Main Methods:
- Retrospective analysis of 12 patients assessed at the University Health Network between 2004 and 2014.
- All patients underwent brain magnetic resonance imaging (MRI) during or shortly after intensive care unit admission.
- Data included patient demographics, clinical conditions (respiratory failure, mechanical ventilation, extracorporeal life support), and MRI findings.
Main Results:
- The study population had a median age of 40 years, with 7 of 12 patients being women.
- All patients exhibited extensive microbleeds in the juxtacortical white matter and corpus callosum on MRI.
- The microbleeds spared the cortex, deep/periventricular white matter, basal ganglia, and thalami, with some cases showing internal capsule or posterior fossa involvement.
Conclusions:
- A distinct microbleed phenomenon in the cerebral white matter of critically ill patients has been identified.
- The exact cause remains unclear, but hypoxemia is a potential contributing factor, given similarities to high-altitude exposure-related microbleeds.
