The transoccipital approach for transcranial Doppler ultrasonography of the vertebrobasilar circulation.

With the transoccipital paramedian approach for transcranial Doppler examination of the vertebrobasilar circulation, a complete examination of the intracranial vertebral arteries and basilar artery is possible without moving the patient from the supine position; this may be of value in intensive care conditions. Blood flow velocity and flow direction in these vessels are registered through the occipital bone at relatively more superficial levels, and identification of right and left vertebral arteries usually represents no problem.