Lantz A, Nosher J L, Pasquale S, Siegel R L
Department of Radiology, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, New Brunswick 08903, USA.
Contraception. 1997 Nov;56(5):323-7. doi: 10.1016/s0010-7824(97)00159-5.
This study was designed to define sonographic characteristics and the optimal sonographic technique for localization of the single rod Implanon system. Diagnostic ultrasonography was performed in eight women who had the Implanon rod implanted in the medial aspect of the upper arm. All implants were scanned in the longitudinal and transverse direction using 3.5 MHz, 5 MHz, and 7.5 MHz linear array transducers. Scanning was performed both directly against the skin and with 2 and 4 cm Kiteco ultrasound stand-off pads. Each image obtained was evaluated for detectability of the Implanon rod and the grade of acoustic shadowing produced by the Implanon rod by two independent observers. Discrepancies in evaluation were adjudicated by a third observer. The Implanon rod implant was not directly identified using the transducer and standoff pad combinations. Implanon rods were indirectly identified as a result of the posterior acoustic shadow cast by the Implanon. Best demonstration was achieved with the 5 or 7.5 MHz transducer and a 2 cm stand-off pad in the transverse direction. Appropriate ultrasonographic technique and familiarity with posterior acoustic shadowing patterns generated by the implant provide a noninvasive method for localization of nonpalpable, single rod implants prior to removal.
本研究旨在明确单根依姆平隆系统的超声特征及最佳超声定位技术。对8名在上臂内侧植入依姆平隆棒的女性进行了诊断性超声检查。使用3.5兆赫、5兆赫和7.5兆赫的线性阵列换能器对所有植入物进行纵向和横向扫描。扫描时既直接紧贴皮肤，也使用2厘米和4厘米的Kiteco超声隔离垫。由两名独立观察者对获取的每张图像进行依姆平隆棒的可检测性及依姆平隆棒产生的声影等级评估。评估中的差异由第三名观察者裁定。使用换能器和隔离垫组合未能直接识别出依姆平隆棒植入物。依姆平隆棒因依姆平隆产生的后方声影而被间接识别。在横向使用5兆赫或7.5兆赫换能器及2厘米隔离垫可实现最佳显示效果。适当的超声技术以及对植入物产生的后方声影模式的熟悉程度，为在取出前对不可触及的单根植入物进行定位提供了一种非侵入性方法。
