Nyberg D A, Laing F C, Filly R A
Radiology. 1986 Feb;158(2):397-400. doi: 10.1148/radiology.158.2.3510445.
In an attempt to determine whether sonographic evaluation alone can distinguish normal from abnormal gestation sacs, a retrospective analysis was performed of ultrasound (US) scans from 168 women with threatened abortion. Gestation sacs were judged to be abnormal on the basis of specific sonographic criteria including large size (greater than or equal to 25 mm mean sac diameter) without an embryo; distorted shape; thin (less than or equal to 2 mm), weakly echogenic, or irregular choriodecidual reaction; absence of a double decidual sac; and low position. Two criteria - large sac and distorted shape - had 100% specificity and were called major criteria. The remaining criteria were individually less specific, although 100% specificity was achieved when three or more of these minor criteria were demonstrated. When one major or three minor criteria were present, 53% of abnormal gestations were correctly identified without any false-positive diagnoses. The authors conclude that experienced sonographers can reliably identify many abnormal gestation sacs on a single examination.
为了确定仅通过超声评估能否区分正常与异常妊娠囊，对168例有先兆流产的女性的超声（US）扫描进行了回顾性分析。根据特定的超声标准判断妊娠囊是否异常，这些标准包括：孕囊较大（平均囊径大于或等于25mm）但无胚胎；形状扭曲；绒毛膜蜕膜反应薄（小于或等于2mm）、回声弱或不规则；无双蜕膜囊；以及位置低。其中两个标准——大孕囊和形状扭曲——具有100%的特异性，被称为主要标准。其余标准单独来看特异性较低，不过当出现三个或更多这些次要标准时可达到100%的特异性。当存在一个主要标准或三个次要标准时，53%的异常妊娠可被正确识别，且无假阳性诊断。作者得出结论，经验丰富的超声检查人员在单次检查中能够可靠地识别许多异常妊娠囊。
