DIFFICULTIES IN EXAMINATION OF THE ORIGIN OF THE VERTEBRAL ARTERY BY DUPLEX AND COLOR-CODED DOPPLER SONOGRAPHY - ANATOMICAL CONSIDERATIONS

Despite progress in ultrasonographic techniques visualisation of the o rigin of the vertebral arteries, particularly the left, by duplex and colour Doppler imaging, still poses a problem in a significant number of patients. In anatomical and radiological studies we demonstrated an anomalous origin in 6%, the left vertebral artery originating directl y from the aorta in most cases. The origin from the subclavian artery was found to be posterior in 44% and inferior in 6%. The V1 segment of the vertebral artery (from its origin to the entry into the foramen t ransversarium) was tortuous in 47% of cases. These anatomical variants and variations in the course of the vessel contribute to the nonvisua lisation of the origin of the vertebral artery by duplex and colour Do ppler imaging. With respect to tortuosities technical modifications fo r better visualisation are suggested and possible implications for sur gery are discussed.