Intracranial Duplex Doppler: Practical Uses in Pediatric Neurology

The value of pulsed Doppler studies of the cerebral vessels of neonates, infants, and children having neurologic and neuro-surgical problems is presented. In this study, Resistive Index—[(peak systolic velocity- end-diastolic velocity)/peak systolic velocity] x 100—was used in correlative studies of pediatric patients having hydrocephalus, extra-axial collections, shunt malfunctions, vascular malformations, and craniocerebral injuries. Age-related normal values for Resistive Index are defined, with special attention to the expected values in patients having normally functioning ventriculoperitoneal shunts. Correlations of Resistive Index with intracranial pressure in animal models, as well as a variety of pathologic pediatric neurosurgical conditions, emphasize the usefulness of pulsed Doppler studies in some conditions as well as limitations in others. (J Child Neurol 1989;4:577-S86). High-resolution ultrasonography has ex-quisitely visualized the brain and spinal cord of neonates. Pulsed Doppler studies, used primarily to evaluate blood flow, using the anterior fontanelle as a sonic window, have also been ex-tremely helpful in studying neonates and infants and more recently, transcranial pulsed Doppler hard