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A Thrombotic Stroke Model Based On Transient Cerebral Hypoxia-ischemia
Published on: August 18, 2015
Paradoxical brain embolism in an acute stroke
Takeshi Iwanaga1, Yasuyuki Iguchi, Kensaku Shibazaki
1Department of Stroke Medicine, Kawasaki Medical School, Japan. tiwaanaga@kzd.biglobe.ne.jp
Journal of the Neurological Sciences
|February 20, 2007
Summary
Diagnosing paradoxical embolism, a stroke cause, is challenging. Transesophageal echocardiography (TEE) proved crucial in confirming a clot in a patent foramen ovale in this stroke patient.
Area of Science:
- Cardiology
- Neurology
- Vascular Medicine
Background:
- Paradoxical embolism to the brain is clinically challenging to diagnose.
- Atrial fibrillation is a common risk factor for stroke, complicating diagnosis.
Observation:
- An 84-year-old woman presented with bilateral hemispheric strokes.
- Deep venous thrombosis (DVT) and pulmonary embolism were identified.
- A right-to-left shunt was detected via contrast-transcranial Doppler ultrasound.
Findings:
- Transesophageal echocardiography (TEE) visualized a 4-cm thrombus within a patent foramen ovale.
- The thrombus extended from the right to the left atria.
- Multiple imaging modalities facilitated rapid diagnosis of paradoxical embolism.
Implications:
- Transesophageal echocardiography is vital for confirming paradoxical embolism.
- Identifying deep venous thrombosis is key to understanding the stroke mechanism.
- This case highlights the utility of advanced imaging in diagnosing complex cerebrovascular events.
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