Detection of cerebral microemboli in patients with ischemic stroke: A preliminary observation

The technique of transcranial Doppler ultrasonography (TCD) is capable of detecting cerebral microemboli in the intracranial artery. These microemboli present with high intensity transient signals in TCD spectral curves together with a chirping sound during their passage through the sample volume. In our neurosonographic laboratory, microembolic signals were found in 5 patients with ischemic stroke during the procedure of transcranial color-coded real time ultrasonography. In patients with cardiogenic embolism, these signals, when present, were noted in more than one artery. On the other hand, in patients with symptomatic carotid artery stenosis, the microembolic signals were only present in the ipsilateral perfusion artery. From our preliminary experience, detection of cerebral microemboli is helpful in localizing the source of emboli. It may be useful for subtype classification of ischemic stroke.