INTRAVASCULAR ULTRASOUND APPEARANCE OF NORMAL AND MILDLY DISEASED CORONARY-ARTERIES - CORRELATION WITH HISTOLOGIC SPECIMENS

Intravascular ultrasound imaging was performed in vitro on six histolo gically normal and 104 minimally diseased arteries in patients aged 13 to 83 years. This study tested the hypothesis that normal coronary ar teries produce a three-layer image that corresponds to the histologic layers of intima, media, and adventitia. The results showed a very goo d correlation between area of the echolucent ultrasound layer with the media and the inner echogenic layer with intimal area. In addition, a three-layer appearance was consistently seen when the internal elasti c membrane was present with or without intimal hyperplasia. If the int ernal elastic membrane was absent, a three-layer appearance was still seen if the collagen content of the media was low. However, a two-laye r appearance was observed when there was absence of the internal elast ic membrane as well as a high collagen content of the media.