Third trimester placental volume and biometry measurement: A method-development study

Abstract

a b s t r a c tObjectives: To test the hypothesis that third trimester placental biometry and volume can be measured by two-dimensional (2D) and three-dimensional (3D) ultrasound in utero, determining which method of measurement was most strongly correlated with true placental size ex vivo. Methods: Singleton pregnancies underwent placental ultrasound within seven days of delivery (n ¼ 87, 29 þ3 e41 þ5 weeks). Length and width (linear and curvilinear) and depth were estimated. Placental volume (PV) was estimated using 2D ellipse and shell techniques and 3D rotational (15⁰ and 30⁰ rotation angles) and multiplanar (5 and 10 mm slicing intervals) techniques. Measurements were compared to their true correlates following delivery. Intra-and inter-observer reliabilities of candidate placental size estimates were assessed by intraclass correlation coefficient (ICC). Results: Curvilinear placental length (R s ¼ 0.24, p ¼ 0.031), width (R s ¼ 0.27, p ¼ 0.013) and depth (R s ¼ 0.31, p ¼ 0.0056) correlated well with ex vivo measurements. All methods of PV estimation were related to ex vivo volume (R s ! 0.32, p < 0.01) but not placental weight (p > 0.05); 30 rotational estimation demonstrated the strongest biological correlation (R s ¼ 0.40, p ¼ 0.0004). Intra-and interobserver placental size measurements intraclass correlation coefficients were suboptimal (0.59e0.70 and 0.10e0.58 respectively). Discussion: We have demonstrated that it is possible to obtain information about the size of the third trimester placenta in utero using 2D and 3D ultrasound. However it is essential that the reliability (particularly interobserver reliability) of these estimates is improved prior to prospective studies to determine their predictive value.

A placenta clinic approach to the diagnosis and management of fetal growth restriction

“…[44][45][46] The simplest method uses 2-dimensional ultrasound to measure maximum placental length, thickness, overall placental shape, and cord insertion. 37,[47][48][49] Normal placental findings in the second trimester are summarized in Table 3 37 and illustrated in Figure 1 and Supplementary Video 1.…”

Ultrasonographic, pharmacologic and pathologic examination of the fetoplacental circulation

“…We tried to eliminate this by standardizing the measurement points. Based on the results obtained, only the cross-section area of the arteries showed deviation, which corresponds to the data reported in the literature [50][51]. This difference also plays a role in the differences in flow in the arteria umbilicalis, but the causative relationship is not clear yet.…”

“…Pathological lesions affecting the placental vessels may further complicate the circulation (calcification, reduced capillarisation, decreased cytotrophoblastic proliferation, chronic vascular stenosis, infarction, fibrin deposition) that can prevent fetal development, although a single pathologic alteration does not usually cause severe IUGR and in milderforms may be present in healthy pregnancies too[50][51]. Ultrasonographic examination of the placenta3.4.1.…”

Maternal Hematological Parameters and Placental and Umbilical Cord Histopathology in Intrauterine Growth Restriction

“…It is not clear yet how placental weight and volume are related. Sonographically, placental volume can be used to detect placental growth restriction that precedes fetal IUGR by several weeks [9]. There are placental vascular pathologies (calcification, reduced capillarization in the terminal villi, reduced cytotrophoblast proliferation, chronic villitis, infarcts, perivillous fibrin deposition, etc.)…”