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Updated: Jul 11, 2026
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Combined Near-infrared Fluorescent Imaging and Micro-computed Tomography for Directly Visualizing Cerebral Thromboemboli
Published on: September 25, 2016
Cerebral emboli in cryptogenic ischemia: a reason to enforce diagnostic testing
W D Niesen1, U Sliwka, A Lingnau
1Department of Neurology, Friedrich-Schiller University Jena, Jena, Germany.
Summary
Microembolus detection using transcranial Doppler identified microembolic signals (MES) in 45% of cryptogenic stroke patients. This suggests an embolic source may underlie some cryptogenic strokes, warranting further investigation.
Area of Science:
- Neurology
- Vascular Neurology
- Diagnostic Imaging
Background:
- Cryptogenic stroke, or stroke of unknown origin, presents significant diagnostic and therapeutic challenges.
- A subgroup analysis focused on microembolus detection in patients with cryptogenic strokes.
Purpose of the Study:
- To evaluate the detection rate of microembolic signals (MES) in patients with cryptogenic cerebral ischemia.
- To determine if MES detection can indicate an embolic source in cryptogenic strokes.
Main Methods:
- Seventy-eight patients with acute cerebral ischemia in the anterior circulation were enrolled.
- Transcranial Doppler (TCD) was used to monitor for MES at admission and at two 24-hour intervals.
- All patients underwent a standard stroke work-up; 20 patients had cryptogenic ischemia.
Main Results:
- Microembolic signals (MES) were detected in 30% of cryptogenic stroke patients during the first examination.
- MES detection rates were 20% in the second and 20% in the third examinations.
- Overall, MES were detected in 45% of patients with cryptogenic ischemia.
Conclusions:
- Microembolus detection is feasible in cryptogenic stroke patients.
- The presence of MES suggests that an embolic etiology may be partially responsible for cryptogenic strokes.
- Detection of MES in cryptogenic ischemia supports the need for extensive retesting to identify potential embolic sources.
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