A HEAD AND TRANSDUCER HOLDING TECHNIQUE F OR TCD MONITORING OF THE VERTEBROBASILAR CIRCULATION

For monitoring the Doppler spectrum of the vertebral and basilar arter ies the authors have used a microball vacuum cushion for fixing the he ad of the patient in lateral, moderately anteflected position, and a t hree lockable joint type instrument holder allowing adjustment of the probe suboccipitally. This setting was used for transforminal vertebro basilar emboli monitoring in 5 patients having prosthetic heart valves . As an alternative technique a microball filled vacuum collar was tri ed out for immobilisation of the patient's head, and a snake neck type surgical instrument holder for guiding the probe.