Comparison between multiplanar and rendering modes in the assessment of fetal atrioventricular valve areas by 3D/4D ultrasonography

Abstract

Comparação entre os modos multiplanar e renderizado na avaliação da área das valvas atrioventriculares fetais por meio da ultrassonografia 3D/4DComparison between multiplanar and rendering modes in the assessment of fetal atrioventricular valve areas by 3D/4D ultrasonography Abstract Objective: To compare the agreement of multiplanar and rendering modes in the assessment fetal atrioventricular valves (mitral and tricuspid) areas by three-dimensional (3D) ultrasonography using the software spatio-temporal image correlation (STIC).Methods: We conducted a prospective cross-sectional study with normal pregnant women, with single fetuses, between 18-33 weeks. To measure the areas, we used the plan of fourchamber view. In the case of multiplanar, the plane was rotated on the axis "Z" form the heart to position at 9h. For rendering, the green line (region of interest -ROI) was placed from the atria of the heart perpendicular to the crux. The agreement was assessed by a Bland-Altman (limits of agreement) using the relative difference between the measures: ((rendering mode) -(multiplanar mode)) / (average).Results: 328 fetuses were evaluated. We have not identified the occurrence of systematic error between methods: the average relative difference was 1.62% (-2.07% to 5.32%, confidence interval 95%) in the mitral and 1.77% (-1.08% to 4.62%) in the tricuspid valve. The limits of agreement between methods were -65.26% to 68.51% for the mitral and -49.91% to 53.45% for the tricuspid.Conclusions: There was no systematic error between modes and thus the observed values for the area of fetal atrioventricular valves can be used for comparisons needs to be corrected. However, relatively large variations may be observed when repeating the measurement area by different modes.

Viewing rate and reference ranges for papillary muscle areas of the fetal heart using four‐dimensional ultrasound in the rendering mode

“…However, the prenatal diagnosis of any problems is only possible in symptomatic situations, including hypoxia/anoxia due to placental insufficiency, because of the inability of conventional echocardiography to assess the containment system of atrio‐ventricular valves . Previously, the rings of the atrio‐ventricular valves were evaluated, and the reference ranges determined, but there are no studies that specifically involve the tricuspid and mitral valve chordae tendinae and papillary muscles in fetuses with normal heart anatomy …”

“…According to Turan et al ., by using a low level of transparency, the rendering mode can be applied to the fetal heart at the boundary between the cardiac chambers and ventricular walls, thereby allowing improved visualization of cardiac structures, which is not possible with 2D ultrasound. Moreover, the rendering mode has been used to measure the area of several fetal heart structures such as the atrio‐ventricular valve annulus and inter‐ventricular septum …”

“…The images can be viewed in both the multiplanar and rendering modes. A few articles on the STIC rendering mode to assess fetal cardiac structures have been published . The aim is to obtain planes for evaluating the inter‐atrial and inter‐ventricular septae, rings of the atrio‐ventricular valves and alignment of the great vessels.…”

Fetal Myocardial Wall Area: Constructing a Reference Range by Means of Spatiotemporal Image Correlation in the Rendering Mode

“…The upper limit of 33 weeks 6 days of gestation was established because after this GA, the fetus position on the back and the imaging artifacts from the ribs are more frequent, hampering or even preventing the adequate analysis of fetal cardio-STIC [13,14,15,16,17]. …”

“…According to Turan et al [12], by using a low level of transparency, the rendering mode can be applied to the fetal heart at the boundary between the cardiac chambers and ventricular walls, thereby allowing improved visualization of cardiac structures. Previous studies using 3DUS have evaluated the atrioventricular valve annulus [13,14,15] and the thickness of the interventricular septum in normal fetal hearts [16,17]. …”