Assessment of fetal anatomy in the first trimester using two- and three-dimensional ultrasound

Abstract

The objective of this study was to perform a complete anatomical survey of the fetus at 12-13 weeks gestation using stored volumes acquired by a three-dimensional (3D) scanner. 159 consecutive women at 12-13 weeks gestation who had a routine early pregnancy scan in our unit were recruited. A complete survey of the fetal anatomy was attempted by two-dimensional (2D) transabdominal and, if needed, transvaginal ultrasound. Then, using a 3D transvaginal probe, two volumes of the whole fetus were acquired. A complete anatomical survey (excluding anatomy of the heart) was attempted using the stored data. A complete anatomical survey was achieved in 93.7% (149) of cases with 2D ultrasound compared to 80.5% (128) of cases with 3D volume acquisition (p<0.001). The nuchal translucency was measured with 2D scanning in 98.7% of cases and in 91.8% of cases using 3D volumes. The mean time to perform a 2D scan was 12.2 min standard deviation (SD 3.4 min) while the mean time to obtain and examine the stored volumes was 8.4 min (SD 1.45 min, p<0.001). Real-time 2D ultrasound is still the best way to examine fetal anatomy in the first trimester. However, 3D ultrasound can be a useful addition to clinical practice, providing views not easily obtained by conventional 2D ultrasound. It can potentially minimize actual scanning time and provides an excellent way to store scanned data.

Three-dimensional ultrasound in prenatal diagnosis

“…A major advantage of a 3D dataset is the ability to analyze volumes offline and away from the scanner, which can increase scanning efficiency and patient throughput [10 • ,117 • , [125][126][127] (see the example in Fig. 3).…”

Virtual embryoscope for detection of structural abnormalities in first trimester pregnancy

“…The 3D reconstructed view could be as good as the respective 2D images but the fetal part could not be fully examined in a given volume. 5 In 1990, Timor-Tritsch et al introduced 'sonoembryology'. They used a high frequency vaginal probe to image early pregnancies.…”

3D/4D Ultrasound in Prenatal Diagnosis

“…Complete anatomy could be obtained in 93.7% with 2D imaging versus 80.5% with 3D. 11 Their conclusions were that 2D remains the best way to examine the fetal anatomy during the first trimester, but 3D can be a useful addition. Specifically for fetal cardiac studies, several researchers have analyzed the value of 3D US, particularly in the form of spatiotemporal image correlation (STIC).…”