The papillary muscle may lead to a reduction of the penetrating ultrasound energy by reflection, scattering and absorption. Distal to the papillary muscle contrast medium may not be stiumulated to emit harmonic frequencies, resulting in a “shadow”. This can complicate the determination of ejection fraction and left ventricular volumes. This situation can only be avoided…
blooming
Blooming describes a phenomenon, that ultrasound signals due to high concentration of contrast medium outshine adjacent weaker signals, similar to an over-exposure in photography. Blooming can hamper the assessment of a ventricular thrombus or the detection of a perfusion signal from the endocardium during a stress test. It also means that vessels in the myocardium…
attenuation, shadowing
Ultrasonic contrast agents consists of bubbles, which absorb acustic energy, when they beginn to oscillate. Acustic energy is reduced, the higher the concentration of the contrast medium and the greater the distance to the transducer. High concentrations of contrast agent not only lead to a blooming – effect, but also to a strong decrease of…
swirling
Optimal images can be obtained only in rare cases with the default settings of an ultrasound device. In conventional echocardiography an improvement can be achieved in imaging quality eg by adjusting the frequency of the transducer. The key to informative images in contrast sonography is the mechanical index, abbreviated MI, which is displayed on the…
