Makoto NIIZAWA, Hideaki ISHIDA, Pablo MORIKAWA, Hiroko NAGANUMA, Syoko NAGANUMA , Osamu MASAMUNE

The First Department of Internal Medicine, Akita University School of Medicine

キーワード : Ultrasound, Diaphragm, Artifact, Intrathoracic tumor

The echogenic layers visualized above the hepatic dome in right intercostal sagittal or oblique scanning are usually called "diaphragmatic echo" or "diaphragmatic echo complex." We have recently encountered four cases of intrathoracic tumors in which the right intercostal scanning failed to visualize the diaphragm at its true position and an echogenic line was seen dorsal to the tumor. When a tumor is located cranially to the liver, and even if an echogenic line might be visualized above the tumor by ultrasound, the possibility of intrathoracic tumor must be taken into account. In such cases, it is necessary to observe movement of the tumor separate from that of the liver, using real time sonography. It is also recommended that the scanning plane be altered in order to change the angle of the ultrasound beam.