Bondestam S
Department of Radiology, Helsinki University, Finland.
J Ultrasound Med. 1992 Jun;11(6):253-6. doi: 10.7863/jum.1992.11.6.253.
The echo of the needle tip used in sonographically guided needle aspiration biopsies was studied in A mode. The biopsy transducer was placed in a water tank and needles parallel to the beam axis were used. The beveled needle tip produced two echoes, which were probably generated by diffraction at the edge of the far end of the tip and by the sharp edge of the needle tip opening. The distal echo was more intense than the proximal one. When a stylet was inserted the proximal echo disappeared as the diffracting edges decreased to a single echo. Inserting a stylet did not enhance the echoes. Roughening of the needle shaft did not enhance echogenicity, whereas side ports in the shaft produced a greater number of echo peaks.
在A型超声模式下，对超声引导下针吸活检中使用的针尖回声进行了研究。将活检换能器置于水箱中，并使用与声束轴平行的针。带斜面的针尖产生两个回声，这可能是由针尖远端边缘的衍射以及针尖开口的尖锐边缘产生的。远端回声比近端回声更强。当插入针芯时，随着衍射边缘减少到单个回声，近端回声消失。插入针芯并不会增强回声。针杆粗糙化不会增强回声，而针杆上的侧孔会产生更多的回声峰值。
