Role of Transcranial Doppler Ultrasonography in Detecting and Excluding Ischemic Stroke in the Emergency Department: A Prospective Observational Study.

Introduction: To determine whether color doppler ultrasonography (CDUS) and transcranial Doppler ultrasonography (TCD) can be used as an alternative test to cranial computed tomography angiography (CTA) by detecting vascular occlusions at the bedside in the emergency department (ED). Methods: This is a prospective, observational, and single-center study. It was performed on patients aged 18 years and older who were examined with a preliminary diagnosis of ischemic stroke and presented to an ED within the first 48 hours after the onset of symptoms. TCD, CDUS and vertebral artery doppler ultrasound were performed on one hundred and three patients. Computed tomography angiography was conducted as well and TCD and CDUS findings were compared. Results: Over one month, thirty-three patients were included in the study. The median age of the patients was 67 (52.5-78), and 57.6% (n=19) were male. When the TCD findings were compared with the gold standard (CTA), the negative predictive value of TCD for middle cerebral artery (MCA) was 96.5%. Both right and left carotids could be visualized optimally in all patients with CDUS. In the vertebral artery ultrasound examination, the right and left vertebral arteries were optimally visualized in all patients. Left vertebral artery ultrasound and CTA findings were completely compatible. Conclusion: Transcranial Doppler ultrasonography, a fast, inexpensive, non-invasive, and reproducible method, may have a role in the early detection or exclusion of ischemic strokes where time is critical. This suggests that TCD may be a helpful method in the ED for the early exclusion of acute MCA occlusions.