This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Stroke and TIA, Subject name: Medicine
Paradoxical embolism is detected by? 
Select and explain. 
A. MRI Chest, B. Bubble contrast Echocardiography, C. CT scan Chest, D. Impedance plethysmography
B: Bubble contrast Echocardiography
Answer: B: Bubble contrast Echocardiography 
Explanation: Paradoxical embolism Condition where a clot from venous return enters into the left atrium and left ventricle. Hencefoh, it can travel to the brain leading to cryptogenic stroke. Have a patent foramen ovale which allows transit of clot(s) in this fashion. Dx- Bubble contrast echocardiography is performed.