[FETAL ANATOMY ASSESSMENT AT 11+0-13+6 W.G. AFTER ACQUISTION OF A SINGLE 3D VOLUME--MYTH OR REALITY?]

The first trimester scan at 11+0-13+6 weeks of gestation (wg.) plays an important role in contemporary perinatal care. Implementation of high frequency 3D volume probes allows acquisition of high quality volume data sets with increased spatial resolution. Consequently, better assessment of many fetal organ systems can be performed at an early gestational age.

To evaluate the success rate of 3D ultrasound visualization of major anatomic fetal organ systems after a single 3D volume data aqcuisition at 11+0-13+6 w.g.

A group of 186 first-trimester fetuses were scanned in MC "Markovs", Sofia between 01.11.2013-01.09.2014 with Voluson 730 Expert (GE Healthcare) ultrasound equipment. Aqcuisition of multiple 3D volumes of the entire fetus (transabdominally or transvaginally) were obtained in each case during fetal quiescence. An off-line analysis with a specialized software on a single 3D volume data set was then performed. All major fetal organ systems normally examined during the first trimester scan were analyzed.

Visualization after acquisition of a single 3D volume from the entire fetus was achieved in more than 90% of cases. Lower success in the visualization was encountered with the following fetal structures: lips and retronasal triangle (76.3%), fetal profile (85.5%), skin over the spine (76.3%), bladder and kidneys (80.6%). The complete fetal anatomy survey was successful in more than 70% of the cases.

Acquisition of a single 3D volume data set from the complete fetus at 11+0 to 13+6 w.g. provides appropriate information for the basic evaluation of all major fetal anatomic structures.