妇产科超声(B超)培训 常见的超声效应与图像伪差（Ultrasonography (ultrasound) of gynecology and obstetrics (ultrasound) was used to train the ultrasound effect and the false difference）.doc

妇产科超声(B超)培训 常见的超声效应与图像伪差（Ultrasonography (ultrasound) of gynecology and obstetrics (ultrasound) was used to train the ultrasound effect and the false difference） Common ultrasonic effect and image pseudo difference The pseudo difference of the acoustic image is the difference between the image of the fault and the corresponding anatomical image It is. There are several main types. One, multiple reflections The pseudo-difference produced by multiple reflections is called multiple reflections and multiple echoes. Reverberation effect and ringing effect belong to many Once the Shoot. Reverberation effect (reverberationeffect) : when the beam scanning large smooth interface in vivo, the echo of part The probe Its accepted, and its between the probe surface and the reflector. This shows that the second or third attenuated images can be found Larger liquid The front wall of the dark area shows the repeated and shifting images above the large interface. The gallbladder, bladder, and large cyst can be mixed Effect of shadow The examination of the anterior wall can be mistaken for thickening, secretion or tumor of the wall. There may also be some anterior wall lesions such as gallbladder Uplift sex Lesions, bladder cancer missed diagnosis. The amniotic fluid in the uterine in the middle and late trimester can be caused by multiple reflections in the anterior abdominal wall The front wall The pseudo image of the placenta. Ringingeffect: the interface of soft tissue and aerated tissue (lung, gastrointestinal tract, etc.) at the interface Acoustic features The impedance varies widely, the sound wave is close to all reflection, cannot penetrate the second medium. At this point sound waves are launched from the interface and the probe Between the surface Back and forth oscillations, forming multiple reflections of a certain distance, or a strong reflection of clutter. Ultrasonic scanning metal foreign body, metal Intrauterine device A string of light echoes from the width of a c