Christiane Simioni

Heart stroke volume, cardiac output, and ejection fraction in 265 normal fetus in the second half of gestation assessed by 4D ultrasound using spatio-temporal image correlation

Objectives. The aim of this study was to establish nomograms for fetal stroke volume (SV), cardiac output (CO), and ejection fraction (EF) using four-dimensional ultrasound with spatio-temporal image correlation (STIC) modality. Methods. The fetal heart was scanned using STIC modality, starting with classic four-chamber view plane, during fetal quiescence with abdomen uppermost, at an angle of 20–30°, without color Doppler flow mapping. In post-processing virtual organ, computer-aided analysis technique was used to obtain a sequence of six sections of each ventricular volume in end-systolic volume (ESV) and end-diastolic volume (EDV). The SV (SV = EDV–ESV), CO (CO = SV × fetal heart rate), and EF (EF = SV/EDV) for each ventricle were then calculated. Intra- and interobserver agreement were then calculated. Results. Two hundred sixty-five fetuses, ranging in gestational age (GA) from 20 to 34+6 weeks, were included in the study. The left and right SV and CO increased exponentially with gestation and EF remained fairly stable through gestational. Mean left and right SV increased from 0.211 ml and 0.220 ml at 20 weeks to 1.925 ml and 2.043 ml, respectively, at 34 weeks. Mean left and right CO increased from 30.25 ml/min and 31.52 ml/min at 20 weeks to 268.49 ml/min and 287.80 ml/min, respectively, at 34 weeks. Both left and right mean EF remained constant at around 0.63 with advancing GA. Nomograms were created for LSV, RSV, LCO, RCO, LEF, and REF vs. gestational age. Intra- and interobserver agreement reached 95%. Conclusions. Four-dimensional ultrasound using STIC represents a simple and reproducible method for estimating fetal cardiac function. STIC seems to overcome many of the pitfalls of conventional ultrasound methods and has the potential to become the method of choice.

Evolution of 3-D power Doppler indices of fetal brain in normal pregnancy.

We assessed the vascular indices of the anterior territory of the middle cerebral artery (MCA) in normal pregnancies using 3-D power Doppler (3DPD). A cross-sectional study was carried out on 90 normal pregnancies between 24 and 35 weeks. All examinations were performed by a single operator using a volumetric transducer. The anterior territory of the MCA was scanned and the volumes were captured using 3DPD. The sphere mode of the VOCAL program was used to calculate the following vascular indices: vascularization index (VI), flow index (FI) and vascularization and flow index (VFI). Models of polynomial regression and Pearsons correlation coefficient were used to evaluate the correlation between gestational age (GA) and the vascular indices. The 3DPD vascular indices had a low correlation with gestational age (VI - r = 0.324, p = 0.002; FI - r = 0.375, p < 0.001; VFI - r = 0.374, p < 0.001). There was a low correlation between GA and the 3DPD vascular indices of the anterior territory of the MCA.

Reference ranges of atrioventricular valve areas by means of four-dimensional ultrasonography using spatiotemporal image correlation in the rendering mode.

This study aims to determine reference curves for fetal atrioventricular valve areas by means of three‐dimensional ultrasound using the spatiotemporal image correlation (STIC) software.

Reference Range for Fetal Interventricular Septum Area by Means of Four-Dimensional Ultrasonography Using Spatiotemporal Image Correlation

Objective: To determine reference range for fetal interventricular septum area by means of 3-dimensional ultrasonography (3DUS) using the spatiotemporal image correlation (STIC) method. Methods: A prospective, cross-sectional study was conducted on 328 normal pregnant women between the 18th and 33rd gestational weeks. To obtain the interventricular septum area, a virtual plane was used, with the green line (region of interest) adjacent to the external margin of the septum, which was manually delimited. To evaluate the correlation of the septum area with the gestational age, different regression modes were evaluated. The intraclass correlation coefficient was used to evaluate the interobserver reproducibility. Results: The interventricular septum area showed correlation with the gestational age (r = 0.81). The mean increased from 0.47 ± 0.10 cm2 in the 18th week to 2.42 ± 1.13 cm2 in the 33rd week of gestation. The mathematical equation that best represented this correlation was provided by linear regression: interventricular septum area = 0.0511 × gestational age (R2 = 0.095). The interobserver reproducibility was good, with bias of 0.01 cm2, precision of 0.07 cm2 and absolute limits of agreement of -0.14 and +0.15 cm2. Conclusions: Reference range for fetal interventricular septum area were determined by means of 3DUS using STIC in the rendering mode and were shown to be reproducible.

Fetal cardiac output and ejection fraction by spatio-temporal image correlation (STIC): comparison between male and female fetuses

OBJECTIVE To compare the cardiac output (CO) and ejection fraction (EF) of the heart of male and female fetuses obtained by 3D-ultrasonography using spatio-temporal image correlation (STIC). METHODS We conducted a cross-sectional study with 216 normal fetuses, between 20 and 34 weeks of gestation, 108 male and 108 female. Ventricular volumes at the end of systole and diastole were obtained by STIC, and the volumetric assessments performed by the virtual organ computer-aided analysis (VOCAL) rotated 30º. To calculate the DC used the formula: DC = stroke volume / fetal heart rate, while for the FE used the formula: EF = stroke volume / end-diastolic volume. The DC (combined male and female) and EF (male and female) were compared using the unpaired t test and ANCOVA. Scatter plots were created with the percentiles 5, 50 and 95. RESULTS The average of DC combined, DC left, DC right, FE right and FE left, male and female were 240.07 mL/min, 122.67 mL/min, 123.40 mL/min, 72.84%, 67.22%, 270.56 mL/ min, 139.22 mL/min, 131.34 mL/min, 70.73% and 64.76% respectively, without statistical difference (P> 0.05). CONCLUSIONS The fetal CO and EF obtained by 3Dultrasonography (STIC) showed no significant difference in relation to gender.OBJECTIVE: To compare the cardiac output (CO) and ejection fraction (EF) of the heart of male and female fetuses obtained by 3D-ultrasonography using spatio-temporal image correlation (STIC). METHODS: We conducted a cross-sectional study with 216 normal fetuses, between 20 and 34 weeks of gestation, 108 male and 108 female. Ventricular volumes at the end of systole and diastole were obtained by STIC, and the volumetric assessments performed by the virtual organ computer-aided analysis (VOCAL) rotated 30o. To calculate the DC used the formula: DC = stroke volume / fetal heart rate, while for the FE used the formula: EF = stroke volume / end-diastolic volume. The DC (combined male and female) and EF (male and female) were compared using the unpaired t test and ANCOVA. Scatter plots were created with the percentiles 5, 50 and 95. RESULTS: The average of DC combined, DC left, DC right, FE right and FE left, male and female were 240.07 mL/min, 122.67 mL/min, 123.40 mL/min, 72.84%, 67.22%, 270.56 mL/ min, 139.22 mL/min, 131.34 mL/min, 70.73% and 64.76% respectively, without statistical difference (P> 0.05). CONCLUSIONS: The fetal CO and EF obtained by 3Dultrasonography (STIC) showed no significant difference in relation to gender.

Fetal lung volume in fetuses with urinary tract malformations: Comparison by 2D-, 3D-sonography and magnetic resonance imaging

Objective. To evaluate the concordance between two-dimensional ultrasonography (2DUS), three-dimensional ultrasonography (3DUS) and magnetic resonance imaging (MRI) in the assessment of lung volume in fetuses with urinary tract malformations (UTM). Methods. This was a cross-sectional study involving 12 pregnancies between 19 and 34 weeks, with various fetal UTM. Pulmonary volume was obtained by 2DUS using the following equation: total lung volume = [right lung antero-posterior diameter (X) × transverse diameter (Y) × cranial-caudal diameter × 0.152 + left lung (X1) × (Y1) × (Z1) × 0.167]. Pulmonary volume by 3DUS was obtained using the virtual organ computer-aided analysis (VOCAL) method with a 30° (VOL30), 18° (VOL18) and 12° (VOL12) rotation. A fast sequence of transverse lung section was also obtained by MRI. The intraclass correlation coefficient was used to evaluate the correlation between the three methods. The paired student t-test was used to compare the means. Results. There was a strong correlation between the three methods, and the highest correlations were between MRI and VOL18 for the right (ICC = 0.913) and left (ICC = 0.947) lungs. A strong correlation was also found between the lung volumes obtained through MRI and VOL12 as well as VOL18 (p = 0.544 and 0.286, respectively). However, for the left lung there was only a correlation between MRI and VOL12 (p = 0.49). Conclusions. There is a good concordance between 3DUS (VOL12) and MRI in the evaluation of lung volume in fetuses with UTM.

Reference curve of the fetal ventricular septum area by the STIC method: preliminary study

FUNDAMENTO: A deteccao precoce de alteracoes septais, tais como a hipertrofia septal comumente presente em fetos de maes diabeticas, contribuiria para a reducao das altas taxas de mortalidade infantil. OBJETIVO: Determinar intervalos de referencia para a area do septo interventricular fetal por meio da ultrassonografia tridimensional (US3D) utilizando o metodo STIC (Spatio-Temporal Image Correlation). METODOS: Realizou-se um estudo de corte transversal com 69 gestantes normais entre a 18a e 33a semanas de gestacao. Utilizou-se como referencia o plano de quatro câmaras com a ROI (Regiao de Interesse) posicionada a partir dos ventriculos, sendo a area do septo delimitada de modo manual. Para se avaliar a correlacao da area do septo interventricular com a idade gestacional (IG), construiram-se diagramas de dispersao e calculou-se o coeficiente de correlacao de Pearson (r), sendo o ajuste realizado pelo coeficiente de determinacao (R2). Foram calculadas medias, medianas, desvios-padrao (dp), valores maximo e minimo. Para o calculo da reprodutibilidade intraobservador, utilizou-se o coeficiente de correlacao intraclasse (CCI). Obteve-se a medida da espessura do septo interventricular e ela foi correlacionada com a IG e a area septal obtida pelo modo renderizado em 52 pacientes utilizando-se o CCI. RESULTADOS: A area do septo interventricular foi altamente correlacionada com a idade gestacional (r = 0,81), e a media aumentou de 0,47 cm2 na 18a para 2,42 cm2 na 33a semana de gestacao. A reprodutibilidade intraobservador foi excelente com CCI = 0,994. Nao se observou correlacao significativa entre a medida do septo interventricular e a IG (R² = 0,200), assim como nao houve correlacao com a area do septo obtida pelo modo renderizado com CCI = 0,150. CONCLUSAO: Intervalos de referencia para a area do septo interventricular entre a 18a e 33a semanas de gestacao foram determinados e se mostraram altamente reprodutiveis.BACKGROUND Early detection of septal changes such as septal hypertrophy commonly present in fetuses of diabetic mothers would help reduce the high rates of infant mortality. OBJECTIVE Determine reference ranges for the fetal ventricular septal area through three-dimensional ultrasound (US3D) using the STIC method (Spatio-Temporal Image Correlation). METHODS We conducted a cross-sectional study with 69 pregnant women between the 18th and 33rd weeks of pregnancy. We used as a reference the four-chamber plane with the ROI (Region of Interest) positioned from the ventricles; the septum area were manually marked. To assess the correlation of the interventricular septum area with gestational age (GA), we constructed scatter plots and calculated Pearsons correlation coefficient (r), and the adjustment was performed by the coefficient of determination (R²). We calculated averages, medians, standard deviations (sd), as well as maximum and minimum values. To calculate the intraobserver reproducibility, we used the intraclass correlation coefficient (ICC). The interventricular septum thickness was measured and it was correlated with gestational age and the septal area rendered in 52 patients using the ICC. RESULTS The interventricular septum area was highly correlated with gestational age (r = 0.81), and the average increased from 0.47 cm² in the 18th week to 2.42 cm² in the 33rd of gestation. The intraobserver reproducibility was excellent with ICC = 0.994. No significant correlation was observed between the interventricular septum measurement and the GA (R² = 0.200), as well as there was no correlation with the septal area rendered with ICC = 0.150. CONCLUSION Reference intervals for the interventricular septum area between the 18th and the 33rd pregnancy week were determined to be highly reproducible.

Prenatal diagnosis of Beckwith-Wiedemann syndrome by two- and three-dimensional ultrasonography

Beckwith-Wiedemann syndrome is a genetic syndrome characterized by macroglossia, omphalocele, fetal gigantism and neonatal hypoglycemia. The authors report a case of Beckwith-Wiedemann syndrome diagnosed in a 32-year-old primigravida in whom two-dimensional ultrasonography revealed the presence of abdominal wall cyst, macroglossia and polycystic kidneys. Three-dimensional ultrasonography in rendering mode was of great importance to confirm the previous two-dimensional ultrasonography findings.

Delineation of vertebral area on the coronal plane using three-dimensional ultrasonography advanced volume contrast imaging (VCI) Omni view: intrarater reliability and agreement using standard mouse, high definition mouse, and pen-tablet.

Objective: To assess the fetal lumbosacral spine by three-dimensional (3D) ultrasonography using volume contrast imaging (VCI) omni view method and compare reproducibility and agreement between three different measurement techniques: standard mouse, high definition mouse and pen-tablet. Methods: A comparative and prospective study with 40 pregnant women between 20 and 34 + 6 weeks was realized. 3D volume datasets of the fetal spine were acquired using a convex transabdominal transducer. Starting scan plane was the coronal section of fetal lumbosacral spine by VCI-C function. Omni view manual trace was selected and a parallel plane of fetal spine was drawn including interest region. Intraclass correlation coefficient (ICC) was used for reproducibility analysis. The relative difference between three used techniques was compared by chi-square test and Fischer test. Results: Pen-tablet showed better reliability (ICC = 0.987). In the relative proportion of differences, this was significantly higher for the pen-tablet (82.14%; p < 0.01). In paired comparison, the relative difference was significantly greater for the pen-tablet (p < 0.01). Conclusion: The pen-tablet showed to be the most reproductive and concordant method in the measurement of body vertebral area of fetal lumbosacral spine by 3D ultrasonography using the VCI.

Assessment of the fetal mitral and tricuspid valves areas development by three-dimensional ultrasonography.

PURPOSE: to evaluate the areas of the atrioventricular valves (tricuspid and mitral) of normal fetuses by the use of three-dimensional ultrasound (3DUS) and the spatiotemporal image correlation (STIC) method. METHODS: a cross-sectional study was conducted on 141 women between the 18th and the 33rd week of pregnancy. Cardiac volumes were measured with a volumetric transabdominal transducer attached to the Voluson 730 Expert equipment. The four chamber plane was used as reference, with the region of interest (ROI) positioned from the ventricles, and the area of the valves was obtained manually. To determine the correlation of the areas with gestational age, scatter plots were constructed and the Pearson correlation coefficient (r) was calculated. Means, medians, standard deviations (SD) and maximum and minimum values were calculated. The simple linear regression model was used to determine reference ranges of valve areas according to the gestational age by the Altman method, with the level of significance set at p<0.05. To calculate the intraobserver reproducibility, we used the intraclass correlation coefficient (ICC) and the Bland-Altman graph. RESULTS: the mitral and tricuspid valve areas were correlated to the gestational age (r=0.80 for the tricuspid and r=0.79 for the mitral valve) and the mean value of the tricuspid and mitral valves increased from 0.22±0.10 cm2 and 0.23±0.10 cm2 on the 18th week to 0.92±0.29 cm2 and 1.08±0.41 cm2 on the 33rd of pregnancy, respectively. The intraobserver reproducibility resulted in an ICC=0.993 (95%CI 0.987; 0.996) and the mean difference was 0.01 cm2 (SD±0.2 cm2 and CI95%±0.4 cm2). CONCLUSION: reference intervals for the areas of the mitral and tricuspid valve between the 18th and the 33rd week of gestation were determined and proved to be highly reproducible.PURPOSE to evaluate the areas of the atrioventricular valves (tricuspid and mitral) of normal fetuses by the use of three-dimensional ultrasound (3DUS) and the spatiotemporal image correlation (STIC) method. METHODS a cross-sectional study was conducted on 141 women between the 18th and the 33rd week of pregnancy. Cardiac volumes were measured with a volumetric transabdominal transducer attached to the Voluson 730 Expert equipment. The four chamber plane was used as reference, with the region of interest (ROI) positioned from the ventricles, and the area of the valves was obtained manually. To determine the correlation of the areas with gestational age, scatter plots were constructed and the Pearson correlation coefficient (r) was calculated. Means, medians, standard deviations (SD) and maximum and minimum values were calculated. The simple linear regression model was used to determine reference ranges of valve areas according to the gestational age by the Altman method, with the level of significance set at p<0.05. To calculate the intraobserver reproducibility, we used the intraclass correlation coefficient (ICC) and the Bland-Altman graph. RESULTS the mitral and tricuspid valve areas were correlated to the gestational age (r=0.80 for the tricuspid and r=0.79 for the mitral valve) and the mean value of the tricuspid and mitral valves increased from 0.22 ± 0.10 cm² and 0.23 ± 0.10 cm² on the 18th week to 0.92 ± 0.29 cm² and 1.08 ± 0.41 cm² on the 33rd of pregnancy, respectively. The intraobserver reproducibility resulted in an ICC=0.993 (95%CI 0.987; 0.996) and the mean difference was 0.01 cm² (SD ± 0.2 cm² and CI95% ± 0.4 cm²). CONCLUSION reference intervals for the areas of the mitral and tricuspid valve between the 18th and the 33rd week of gestation were determined and proved to be highly reproducible.