Transcranial Doppler ultrasound (TCD) can detect circulating cerebral emboli, which may be a risk factor for embolic stroke. We examined the relationship between the results of a TCD study and some of the hematological markers of coagulation. 15 patients with cerebral embolism receiving anticoagulation therapy were evaluated by continuous monitoring over the middle cerebral artery for 30 min, and the number of high-intensity transient signals (HITS) were recorded.
We were able to demonstrate HITS in two of the patients by TCD. Thrombin-antithrombin III complex (TAT) and D-dimer had no influence on the number of HITS. International normalized ratio (INR) intensity was not correlated with the number of HITS, but high-intensity anticoagulation of INR was shown to reduce the frequency of HITS. HITS are not a common phenomenon in patients with cerebral embolism.
