OP25.10: Reproducibility of three‐dimensional volume measurements in the evaluation of fetal lateral ventricles using VOCAL method

Abstract

skull, lateral ventricles of both sides, choroid plexus of both sides, cavum septi pellucidi, thalamus, cerebellum, vermis, cisterna magna and face structures such as eyes, nose, upper lip and profile were displayed. The 2D and 3D images were compared in relation to the completeness of the fetal survey, measurements of five intra-cranium parameters, and time required to obtain the fetal survey. As a control, these 100 fetuses were also examined by an experienced operator (exp) using 2D alone. All images were analyzed by two experienced reviewers blinded to the operator’s identity with subjective criteria. Results: Compared to exp, the visualization rates of most structures were similar between 2D inexp and 3D inexp except the near lateral ventricle and near choroid plexus (95% vs. 80%, 91% vs. 81%, P < 0.05). The visualization rate of the eye in the far field and profile by 2D inexp was 90%, 87%, the rate was improved to 98%, 96% using both 2D and 3D (P = 0.016, 0.022). The image scores of the head and face by 2D inexp were similar to exp, that 3D inexp were lower (34.47 vs. 29.93, P < 0.001). The mean time (seconds) required to complete the head and face survey were shorter by 3D inexp than by 2D inexp (183.4 vs. 226.9, 127.4 vs 205.5, all P < 0.001), but was significantly greater than by 2D exp. Conclusions: 3D volume acquisition at one direction can yield a quicker but less optimal anatomic examination of the fetal head and face compared to 2D. However, when visualization of far eye and facial profile is suboptimal using 2D, selective use of 3D sonography may help.