[Transcranial Doppler contrast study--an ideal method for detection of paradoxical cerebral embolism?]

Cerebral paradoxical embolizations can easily be detected by transcranial Doppler investigations using intravenous echo contrast medium. In some cases of TIA or stroke without vascular or cardiac disease, this method will reveal a right-to-left vascular shunting (e.g. by a patent foramen ovale). However, demonstrating a leakage through the atrial septum does not necessarily reveal the source of an embolus or the cause of the stroke. Thus the question of prolonged antithrombotic therapy must be decided in each individual case.