[Temporal changes in internal echoes in hepatic hemangiomas].

We have discovered a fact that there is a temporal changes of internal echo levels in hepatic hemangiomas. Nine hemangiomas in 6 cases diagnosed by CT were studied ultrasonographically by the real-time scanner during the observation period from 4 to 30 minutes. Low echo portions occupying within the tumor (low echo level ratio) showed temporal changes in 8 of 9 hemangiomas during this period. It is important to take temporal factors into consideration for the ultrasonographic diagnosis of hepatic masses. We coined the term "wax and wane" sign to the temporal changes of internal echo levels in the hepatic hemangioma.