It has been assumed that the introduction of ultrasonography in diagno
stic imaging has led to dramatic changes in imaging routines by replac
ing other modalities like angiography, intravenous urography, and comp
uterized tomography in several diagnostic procedures. The present retr
ospective study from five Norwegian hospitals during the period from 1
978 to 1991 confirm this assumption, showing how ultrasonographic exam
inations have influenced diagnostic routines.