Sonographische Fehlbildungsdiagnostik im zweiten und dritten Trimenon
Obstetric ultrasound is nowadays a well accepted part of
routine antenatal care in many countries. In this setting,
ultrasound has been increasingly used for the prenatal
diagnosis or exclusion of fetal malformations. The prenatal
diag nosis of a fetal disorder permits the enhancement of
antepartum and intrapartum care and therefore has been
shown to decrease the perinatal morbidity and mortality
in some conditions.
As most malformations occur sporadically and in low risk
patients, the identification of those fetuses is only achieved
by application of a general screening examination with a
reasonably high sensitivity. The accuracy of prenatal malfor mation screening is mainly influenced by the experience
and skill of the examiner, but also depends on the gestational age of screening, the equipment used and the visibility (amniotic fluid volume, maternal BMI, fetal position).
The fetal anatomic examination is preferentially performed
at 20-22 weeks gestation, but some anomalies may
be identified only later in gestation.
The accuracy of prenatal ultrasound screening differs
widely, with higher detection rates in centers with highly
trained and skilled examiners. Other reasons why an abnor
mality may be not detected include an early gestational
age, technical difficulties and an unsystematic, incomplete
examination. Continuous theoretical and practical training
of health care professionals is necessary, to further improve
the potential benefits of prenatal ultrasound screening.
Reviewer: Matthias Baumann, Nürnberg
und Dirk Masson, Hamburg
CME Prakt Fortbild Gynakol Geburtsmed Gynakol Endokrinol 2007;3(2):38-51