OC037: Volume calculation of intracranial structures using 3‐D ultrasound in normal and growth restricted fetuses

Abstract

Objectives: To evaluate the feasibility and reproducibility of fetal brain volume segmentation and to estimate differences in the volume of intracranial structures between intrauterine growth restricted (IUGR) and adequate for gestational (AGA) age fetuses. Methods: Total intracranial (TIC), frontal (FR), thalamic (THAL) and cerebellar (CER), volumes were measured using 3-D ultrasound and Virtual Organ Computer-aided Analysis, (VOCAL) in 39 IUGR and 39 AGA fetuses matched by gestational age. Volumes of and ratios between intracranial structures were estimated and differences between the groups calculated. Results: All volumes (TIC, CER, FR) except THAL (P = 0.23) were significantly lower (P < 0.001) in IUGR fetuses. After adjusting volumes for biparietal diameter (BPD) only the frontal lobe volume was significantly lower (P = 0.021) in IUGR fetuses as compared to AGA fetuses. Ratios of the different volumes to HC and BPD were significantly lower in IUGR than AGA fetuses with the exception of the thalamic area. No differences in ratios between the structures were observed between the two groups. Interclass correlation coefficients were 0.97, 0.76, 0.66 and 0.47 for THAL TIC, CER and FR, respectively Conclusions: Volume brain segmentation can be performed with a moderate to high reproducibility. IUGR fetuses have reduced volumes of different intracranial structures when compared with AGA fetuses. These differences are maintained only at the frontal lobe when volumes are adjusted by head biometry. OC038 Sonographic assessment of the normal fetal secondary palate using a novel three-dimensional ultrasound approach Objectives: The aim of this study is to describe a three-dimensional (3D) ultrasound rendering technique to examine the normal fetal secondary palate and to assess its correlation to the real fetal anatomy. Methods: A prospective study was leaded and included 122 fetuses in a low risk population. Fetal ultrasound examinations were performed at 17, 22, 27 and 32 weeks' gestation to determine the normal 3D view of the fetal palate at different gestational ages. The ultrasound scan was performed using strict anterior axial plane of starting reconstruction volume. 3D underside view was obtained. The visualization rates of seven defined anatomical landmarks of the palate are computed for each gestational age. The 3D-view of the fetal secondary palate was compared to the normal anatomic view obtained by surgical foetopathologist examination of fetuses. The visualization rates across gestational ages are compared by use of the Cochrane Q test. The reliability of detection of each anatomical landmark across gestational ages is determined by Cronbach's Alpha. To examine the fetal soft tissues, ultrasound scans were studied at 22 weeks of gestation. The sonographer used an 30 •-inclinated axial 3D-view of the fetal palate. The visualization rates of the uvula and the velum were studied. Results: An anatomic 3D ultrasound view of the fetal secondary palate was obtained at each period of gestation with high anatomic c...

The problem of predicting neurological outcome in early‐onset intrauterine growth restriction

“…In humans, recent studies using magnetic resonance imaging have demonstrated significant differences in the gray matter volume of several brain areas in children who were severely growth restricted in utero as compared with normally grown very preterm children8, 9. The existence of differences in the frontal lobe and the thalami has also been demonstrated in fetuses using three‐dimensional ultrasound10. Rather than true brain injury, these differences are likely to reflect the impact of epigenetic mechanisms resulting from the adaptation of the developing brain to a hypoxic and undernourished environment, which will eventually lead to fetal reprogramming in brain organization.…”