[Transcranial pulsed Doppler. Problems posed by the temporal window (834 patients)].

The absence of temporal windows represents an indisputable limitation of transcranial pulse Doppler (13% of 834 patients). We wanted to specify the elements causing this condition. The patient's age is a determinant factor, especially after 60 years of age. The sex also plays a role, as the window is absent in 23% of women and 6% of men. The use of one device as a rule (95%) does not allow appreciating the results according to the respective qualities of the various systems, which have been diversified as the study was in progress. On the other hand, the technician's experience (this person being experimented with the method) has no significant influence on the results.