BACKGROUND Hemodynamically significant carotid artery stenoses are rarely diagnosed in people under 60 years of age, being mainly secondary to other concomitant diseases. Cerebral blood flow volume, which correlates with cerebrovascular reserve and susceptibility of ischemic symptoms occurrence, may aid in the diagnosis and monitoring of patients with carotid artery disease. In this report we present the case of a patient with significant bilateral carotid stenosis, focusing on the ultrasonographically measured changes in blood flow volume in extracranial arteries following surgeries. CASE REPORT A 41-year-old man with a positive history of transient ischemic attack (TIA) was referred to our department after being diagnosed with significant 80% to 85% right internal carotid artery (ICA) and 60% left ICA stenosis. After successful carotid endarterectomy, the flow volume in extracranial arteries significantly increased (from 755 mL/min to 1053 mL/min) due to an increase of flow volume in the right ICA. With the progression of left ICA stenosis, cerebral blood flow decreased, and the patient presented with a second TIA. Following the successful treatment of the left ICA stenosis (consisting of carotid endarterectomy and stent implantation because neointimal hyperplasia resulted in significant, recurrent 80% left ICA stenosis), an increase in flow volume was observed. CONCLUSIONS Assessment of the blood flow volume in extracranial arteries may be an effective tool in monitoring patients with carotid stenoses. Due to the lack of literature on this topic, further research on cerebral blood flow volume in surgical and non-surgical patients is needed to understand this phenomenon.