Transvaginal probe for fetal magnetocardiography

描述（由申请人提供）：该项目的目标是开发一种比目前经腹胎儿信号记录技术更早的经阴道胎儿心脏和大脑电磁活动仪器。在妊娠少于15周的情况下，使用现有技术记录胎儿体内微小的磁信号是不可能的，在妊娠少于20-24周的情况下，使用标准技术记录胎儿体内微小的磁信号是不可靠的，在任何妊娠期的肥胖患者中也是如此。阴道靠近子宫使其成为肥胖患者或妊娠早期至中期的理想方法。虽然经阴道超声已被使用，但它不能单独检测心脏传导异常，因为它只评估机械事件，而不是导致机械事件的电事件。此外，目前的技术又大又笨重，一般悬挂在天花板安装装置上，大致覆盖足月孕妇腹部的直径。预计经阴道SQUID探针将与磁屏蔽相结合，获得小至妊娠10- 12周胎儿的信号。与目前的胎儿磁记录技术相比，它的优点是可以更接近未成熟的胎儿，并且具有独特的记录角度，这对于信号采集具有优势。由于胎儿/母体组织和流体传输特性的特点，磁信号已被证明远优于电信号用于胎儿心脏记录。

DESCRIPTION (provided by applicant): The goal of this project is to develop an instrument for transvaginal fetal cardiac and brain electromagnetic activity at gestations younger than what can be achieved using present technology of transabdomenal fetal signal recording. Recording minute magnetic signals in the fetus is impossible at gestations earlier than 15 weeks using existing technology and is unreliable using standard technology at gestations less than 20-24 weeks, and at any gestation in an obese patient. The proximity of the vagina to the uterus makes this an ideal approach for the obese patient or the early to mid pregnancy. While transvaginal ultrasound has been employed, it alone cannot detect heart conduction abnormalities, because it only assesses mechanical events, and not the electrical events that lead up to the mechanical events. In addition, present technology is large and bulky, generally suspended from a ceiling mount device and covering roughly the diameter of the full-term maternal gravid abdomen. It is anticipated that a transvaginal SQUID probe would obtain signals from fetuses as small as 10- 12 weeks gestation, in conjunction with magnetic shielding. The advantage over present fetal magnetic recording technologies is that it allows more proximate access to the very immature fetus, and unique recording angles, which are superior for signal acquisition. The magnetic signal has been shown to be far superior to the electric signal for fetal cardiac recording due to the characteristics of fetal/maternal tissue and fluid transmission properties.