Strohbehn K, Dattel B J
Department of Obstetrics, Gynecology, University of California, San Francisco, USA.
J Perinatol. 1995 Nov-Dec;15(6):484-93.
The morbidity and mortality of monoamniotic twins are high. Despite recent advances in imaging, the definitive diagnosis of monoamniotic twins remains elusive. When monoamniotic twins are suspected, the optimal antepartum management is uncertain. A false-positive diagnosis of monoamniotic twins by computed tomographic amniography was investigated. By a Medline search the literature on monoamnionicity from 1966 to January 1994 was reviewed. All reports including diagnostic methods and management of monoamniotic twins were reviewed. All five previous case reports of computed tomographic amniography correctly identified amnionicity in cases in which amnionicity was unclear. Four cases confirmed monoamnionicity and one case excluded monoamnionicity. Four recent series that used ultrasonography revealed a low predictive accuracy (9% to 25%) for the establishment of monoamnionicity when intervening membranes were absent. One recent prospective series revealed a positive predictive value of 80% among five monoamniotic twin pairs with the use of first-trimester ultrasonography. The methods available to diagnose monoamniotic twins are improving. The complications that result from a false-positive diagnosis are discussed and the management and diagnosis of monoamniotic twins are reviewed.
单绒毛膜单羊膜囊双胎的发病率和死亡率很高。尽管近年来影像学有了进展，但单绒毛膜单羊膜囊双胎的明确诊断仍然难以捉摸。当怀疑为单绒毛膜单羊膜囊双胎时，最佳的产前管理尚不确定。本文对计算机断层扫描羊膜造影术误诊单绒毛膜单羊膜囊双胎的情况进行了研究。通过医学文献数据库检索，回顾了1966年至1994年1月期间有关单羊膜囊双胎的文献。对所有包括单绒毛膜单羊膜囊双胎诊断方法和管理的报告进行了回顾。之前关于计算机断层扫描羊膜造影术的5例病例报告均在羊膜情况不明确的病例中正确识别了羊膜情况。4例确诊为单羊膜囊双胎，1例排除单羊膜囊双胎。最近4个使用超声检查的系列研究显示，在无分隔膜时，诊断单羊膜囊双胎的预测准确性较低（9%至25%）。最近1个前瞻性系列研究显示，在5对单绒毛膜单羊膜囊双胎中，使用孕早期超声检查的阳性预测值为80%。诊断单绒毛膜单羊膜囊双胎的现有方法正在改进。本文讨论了假阳性诊断导致的并发症，并对单绒毛膜单羊膜囊双胎的管理和诊断进行了回顾。
