[Normal values for transcranial doppler studies in our medium].

Objective: Transcranial Doppler is a technique which is being used ever more frequently in the study of intracranial arteries and is very useful in the study of cerebrovascular disease. The typical values of a healthy population in our country are unknown. The aim of this study was determine mean velocity and pulsatility index reference values in a healthy population.

Patients And Method: Transcranial Doppler basal examination was carried out on 118 healthy volunteers without prior haematological or cerebrovascular conditions. Those found to have extracranial arterial stenoses were excluded as were those in whom bilateral temporal bone hyperostosis did not permit insonation in either middle cerebral arteries. The nine intracranial arteries were sounded systematically at fixed depths. The mean and standard deviations of each variable were calculated for side, age group and sex.

Results: 49% were males and average age was of 56 years (range, 21-87 years). A sufficient signal to determine the parameters of the study was obtained in 89% of middle cerebral arteries. Statistically significant differences in mean velocity and pulsatility index were found between age groups and sexes.

Conclusions: Sex and age must be taken into account in establishing typical patterns in transcranial Doppler examination. Our results enable parameters of typical values to be established for the adult population in Spain.