In a sense, clinicians detect the microembolus signal (MES) as if NASA were monitoring a comet that could threaten the safety of the Earth at any time. Therefore, the ideal means of MES monitoring should be 24/7, continuous, dynamic, and highly sensitive. However, in actual clinical work, it is difficult for us to do so. First, because miniature portable monitoring devices that do not interfere with the patient’s daily life have not yet been developed, and patients still need to go to the hospital to complete monitoring with “bulky” transcranial Doppler (TCD) devices in a resting state. Second, because the hard skull provides only a few windows for TCD detection, there are still many blind spots for monitoring. Third, the warning significance of MES has not been fully defined clinically, for example, the relationship between the amount and strength of MES and acute ischemic stroke has not been validated. Therefore, a more ideal monitoring method under the current conditions is to focus on the following groups: 1. Patients with multiple risk factors, especially those with neuroimaging confirming the presence of intracranial and extracranial arterial stenosis. 2. Patients with a high risk of recent ischemic stroke as assessed clinically. 3. Patients who are to undergo arteriovenous thrombolysis and need urgent assessment of the effect of thrombolysis. 4. Patients who need to evaluate the clinical value of antiplatelet or anticoagulant drugs for ischemic stroke prevention for real-time or periodic MES monitoring. Considering that in the Chinese population, intracranial artery stenosis/occlusion is more frequent than extracranial artery, and the best site of stenosis or occlusion happens to be located in the temporal bone window where MES is most easily detected by TCD. According to the results of domestic and international studies, the positive rate of MES in patients with severe stenosis (≥70% stenosis) of the middle cerebral artery is much higher than that in patients with mild to moderate stenosis (48% vs. 15%). The positive rate of MES in patients with symptomatic internal carotid artery stenosis was also much higher than that in patients with asymptomatic internal carotid artery stenosis (43% vs. 10%); therefore, TCD monitoring of MES in middle cerebral artery in high-risk patients is particularly suitable for Chinese patients. The duration of monitoring needs to last at least 30 minutes, and the density of monitoring depends on the patient’s specific situation. In general, the more severe the responsible artery stenosis, the more frequent the symptoms, and the stronger the previous MES, the more frequent the monitoring density should be. Given the finding that MES is an independent warning sign of ischemic stroke, clinicians are well positioned to adjust pharmacologic and nonpharmacologic prevention and treatment strategies based on dynamic monitoring results. Clinicians have long been faced with a challenge in the prevention of ischemic stroke and in assessing the effectiveness of arterial thrombolysis. That is, many patients taking adequate doses of anti-small spot drugs, statins, and antihypertensive drugs have not been able to avoid stroke, and clinicians have had difficulty predicting the preventive value of drugs. Although tests such as genetic and platelet activity tests for aspirin or clopidogrel resistance are currently available, the interpretation and early warning value of the results are still not sufficiently vivid and intuitive, and MES monitoring provides an easy, practical and vivid means of solving this dilemma. MES monitoring in TCD can also visually assess the effect of arterial thrombolysis, compare the changes in MES before, during and after thrombolytic therapy, and know in real time whether the occluded artery is recanalized or not, thus allowing for non-individualized dosing of thrombolytic drugs. This allows for non-individualized dosing of thrombolytic drugs and can greatly reduce or avoid “mending” remedies. The detection and treatment of unstable plaque is an important part of the pathogenesis of ischemic stroke and the prevention of arterial-to-arterial ischemic stroke. In the past, the stability of plaque could only be inferred indirectly by the frequency and localization of symptoms, the inverse inference of lesion location and number on neuroimaging, serum C-reactive protein level, and the plaque morphology and echo intensity suggested by vascular ultrasonography. The MES monitoring of TCD provides a direct and visual evidence of the stability of arterial plaques, thus providing a scientific basis for clinicians to manage intracranial and extracranial atherosclerotic plaques in a scientific and rational manner. In conclusion, MES monitoring by TCD is a promising tool for primary and secondary prevention of ischemic stroke, and is an ideal tool for clinicians to manage patients scientifically, evidence-based, and individually.