Abstract
B-flow imaging allows detailed examination of the carotid artery, and can detect microfloating plaque as areas of high brightness. To date, however, there have been no reports providing conclusive proof of this phenomenon. We describe an 86-year-old man who suffered a transient ischemic attack with right hemiparesis. MRI examination revealed multiple infarctions in diffusion-weighted images. B-flow examination was carried out with a LOGIQ 7 system (GE Yokogawa Medical Systems, Tokyo, Japan). Use of a 3-10-MHz broadband linear array transducer revealed a large piece of floating plaque (7.0m×2.0mm) and a piece of micro floating plaque (1.7mm×0.6mm) in the left common carotid artery. Both pieces of plaque were displayed as areas of high brightness. B-flow imaging uses the coded excitation and tissue equalization method, which enables visualization of the blood flow. Coded excitation shows exaggeration of the small reflected signal from red blood cells. Tissue equalization inhibits the signal from resting or slowly moving objects. The mechanism by which floating plaque is displayed as an area of high brightness suggests that the plaque moves so fast that it is difficult to inhibit its signal by tissue equalization.
