Nyberg D A, Mack L A, Harvey D, Wang K
Department of Radiology, University of Washington Hospital, Seattle, Washington.
J Ultrasound Med. 1988 Mar;7(3):129-35. doi: 10.7863/jum.1988.7.3.129.
To determine the potential value in identifying a yolk sac in women with suspected ectopic pregnancies, 211 consecutive women who were referred to pelvic sonography with this clinical indication were prospectively studied. Of the 211 patients examined, 104 proved to have a normal intrauterine pregnancy (IUP), 59 had an abnormal (nonviable) IUP, and 48 had a surgically-proven ectopic pregnancy. Considering only intrauterine "sacs" that lacked a visible embryo, a yolk sack was identified in 16 of 26 (62%) normal IUPs, and 3 of 19 (16%) abnormal IUPs, but was not seen in any of six pseudo-gestational sacs in women with ectopic pregnancies. In comparison, a double decidual sac (DDS) finding was thought to be present in 24 of 26 (92%) normal gestational sacs, 12 of 19 (63%) abnormal gestational sacs, and 2 of 6 (33%) pseudogestational sacs. We conclude that in women in whom a living embryo is not identified, demonstration of a yolk sac is reliable evidence for early IUP, and virtually excludes the possibility of an ectopic gestation. Although a yolk sac is less frequently observed than a DDS finding, it is also more specific evidence for an IUP. Careful attention to the yolk sac should permit earlier, more reliable diagnoses of IUP than previously possible.
为了确定在疑似异位妊娠的女性中识别卵黄囊的潜在价值，我们对211例因该临床指征而接受盆腔超声检查的连续女性进行了前瞻性研究。在接受检查的211例患者中，104例被证实为宫内妊娠正常（IUP），59例为宫内妊娠异常（不可存活），48例为手术证实的异位妊娠。仅考虑那些未见明显胚胎的宫内“囊”，在26例正常IUP中的16例（62%）、19例异常IUP中的3例（16%）发现了卵黄囊，但在异位妊娠女性的6个假妊娠囊中均未发现。相比之下，26例正常妊娠囊中的24例（92%）、19例异常妊娠囊中的12例（63%）以及6例假妊娠囊中的2例（33%）被认为存在双蜕膜囊（DDS）表现。我们得出结论，在未发现有存活胚胎的女性中，卵黄囊的显示是早期宫内妊娠的可靠证据，几乎排除了异位妊娠的可能性。虽然卵黄囊的观察频率低于DDS表现，但它也是宫内妊娠更具特异性的证据。仔细观察卵黄囊应能比以往更早、更可靠地诊断宫内妊娠。
