当前弹性成像主要分类.docx

当前弹性成像主要分类: Compressive elastography : 日立于 200 3 年首次推出商用弹性成像。其他现有产品还包括西门子 ACUSON Antare s及 S200 0 超声探头和 eSie Touch 弹性成像, GE 的 LOGIQ E9 弹性模式和飞利浦的 iU22 弹性模式。 Acoustic radiation force imaging (ARFI): Acoustic radiation force isa phenomenon associated with the propagation of acoustic waves in attenuating media. Attenuation includes both scattering and absorption of the acoustic wave. Attenuation isa frequency dependent phenomenon, and in soft tissues it is dominated by absorption. With increasing acoustic frequencies, the tissue does not respond fast enough to the transitions between positive and negative pressures, thus its motion es out of phase with the acoustic wave, and energy is deposited into the tissue. This energy results ina momentum transfer in the direction of wave propagation and tissue heating. The momentum transfer generates a force that causes displacement of the tissue, and the time scale of this response is much slower than that of the ultrasonic wave propagation. This interaction of sound with tissue can be used to derive additional information about the tissue, beyond what is normally provided in an ultrasonic image. The magnitude, location, spatial extent, and duration of acoustic radiation force can be controlled to interrogate the mechanical properties of the tissue. 临床应用: Liver fibrosis quantification, Breast mass imaging, Colorectal ( 结肠直肠) tumor imaging/st