The objective of the present study was to elucidate the characteristics of the blood flow in vertebral arteries of the 13-16 year-old schoolchildren presenting with acquired myopia of varying degree. A total of 65 children were divided into several groups. Group 1 was comprised off 11 schoolchildren with emmetropia (controls) whereas other groups contained 35 patients with low-degree myopia, 10 ones with moderate-degree myopia, and 9 with high-degree myopia. Progressive myopia was diagnosed in 14 schoolchildren. The children with moderate and high-degree myopia were eventually united into one single group. The blood circulation was studied with the use of the Philips HD7 TD - 5-12 MHz ultrasonic diagnostic system. The patients were examined in the supine position. The linear systolic speed (Vmax, m/s), the linear diastolic blood velocity (Vmin, m/s), resistance index (RI), and the diameter of the vertebral artery (D, cm) were calculated. The measurements were made both at the right and at the left sides of the body at the level of the first segment before the entrance to the bone channel (V1), the second segment inside the bone channel (V2), and the third segment between the exit from the bone channel and the entrance to the cranial cavity (V3). The study has demonstrated asymmetry in the diameter of the vessel and the blood flow velocity at the V1, V2, and V3 levels. The data obtained were treated with the use of the Student's t-test for small samples with the 95% confidence interval. Ultrasound diagnostics of the blood circulation was performed by the «blind method». It was shown that asymmetry of the vessel diameter and the linear systolic blood flow velocity in the extracranial portion of the vertebral arteries of the schoolchildren differing in the intensity and clinical progression of myopia was more pronounced in comparison with that in the control children with emmetropia.