Müller N, Cooperberg P L, Rowley V A, Mayo J, Ho B, Li D K
J Ultrasound Med. 1984 Nov;3(11):515-9. doi: 10.7863/jum.1984.3.11.515.
Using a real-time mechanical sector scanner in a transverse plane of section, the authors noticed that a double image of an intrauterine gestational sac or an intrauterine contraceptive device can be obtained when the transducer is passed over the midline of the abdomen. It was suggested that this is caused by refraction of the sound passing through the medial edges of both rectus abdominis muscles. The authors were able to reproduce this artifact in vitro using isolated human cadaver rectus muscles and imaging a single object in a water bath.
作者在腹部横断面上使用实时机械扇形扫描仪时注意到，当换能器经过腹部中线时，可获得宫内妊娠囊或宫内节育器的双重影像。据推测，这是由于声音穿过双侧腹直肌内侧边缘时发生折射所致。作者能够在体外使用分离的人体尸体腹直肌并在水浴中对单个物体成像来重现这一伪像。
