Imaging, three-dimensional Archives - Revista Brasileira de Ginecologia e Obstetrícia
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2013;35(3):117-122
DOI 10.1590/S0100-72032013000300005
PURPOSE: To evaluate changes to the pelvic floor of primiparous women with different delivery modes, using three-dimensional ultrasound. METHODS: A prospective cross-sectional study on 35 primiparae divided into groups according to the delivery mode: elective cesarean delivery (n=10), vaginal delivery (n=16), and forceps delivery (n=9). Three-dimensional ultrasound on the pelvic floor was performed on the second postpartum day with the patient in a resting position. A convex volumetric transducer (RAB4-8L) was used, in contact with the large labia, with the patient in the gynecological position. Biometric measurements of the urogenital hiatus were taken in the axial plane on images in the rendering mode, in order to assess the area, anteroposterior and transverse diameters, average thickness, and avulsion of the levator ani muscle. Differences between groups were evaluated by determining the mean differences and their respective 95% confidence intervals. The proportions of levator ani muscle avulsion were compared between elective cesarean section and vaginal birth using Fisher's exact test. RESULTS: The mean areas of the urogenital hiatus in the cases of vaginal and forceps deliveries were 17.0 and 20.1 cm², respectively, versus 12.4 cm² in the Control Group (elective cesarean). Avulsion of the levator ani muscle was observed in women who underwent vaginal delivery (3/25), however there was no statistically significant difference between cesarean section and vaginal delivery groups (p=0.5). CONCLUSION: Transperineal three-dimensional ultrasound was useful for assessing the pelvic floor of primiparous women, by allowing pelvic morphological changes to be differentiated according to the delivery mode.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2013;35(3):117-122
DOI 10.1590/S0100-72032013000300005
PURPOSE: To evaluate changes to the pelvic floor of primiparous women with different delivery modes, using three-dimensional ultrasound. METHODS: A prospective cross-sectional study on 35 primiparae divided into groups according to the delivery mode: elective cesarean delivery (n=10), vaginal delivery (n=16), and forceps delivery (n=9). Three-dimensional ultrasound on the pelvic floor was performed on the second postpartum day with the patient in a resting position. A convex volumetric transducer (RAB4-8L) was used, in contact with the large labia, with the patient in the gynecological position. Biometric measurements of the urogenital hiatus were taken in the axial plane on images in the rendering mode, in order to assess the area, anteroposterior and transverse diameters, average thickness, and avulsion of the levator ani muscle. Differences between groups were evaluated by determining the mean differences and their respective 95% confidence intervals. The proportions of levator ani muscle avulsion were compared between elective cesarean section and vaginal birth using Fisher's exact test. RESULTS: The mean areas of the urogenital hiatus in the cases of vaginal and forceps deliveries were 17.0 and 20.1 cm², respectively, versus 12.4 cm² in the Control Group (elective cesarean). Avulsion of the levator ani muscle was observed in women who underwent vaginal delivery (3/25), however there was no statistically significant difference between cesarean section and vaginal delivery groups (p=0.5). CONCLUSION: Transperineal three-dimensional ultrasound was useful for assessing the pelvic floor of primiparous women, by allowing pelvic morphological changes to be differentiated according to the delivery mode.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2010;32(9):426-432
DOI 10.1590/S0100-72032010000900003
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.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2010;32(9):426-432
DOI 10.1590/S0100-72032010000900003
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.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2008;30(4):190-195
DOI 10.1590/S0100-72032008000400006
PURPOSE: to evaluate the accuracy of fetal upper arm volume, using three-dimensional ultrasound (3DUS), in the prediction of birth weight. METHODS: this prospective cross-sectional study involved 25 pregnancies without structural or chromosomal anomalies. Bidimensional parameters (biparietal diameter, abdominal circumference and femur length) and the 3DUS fetal upper arm volume were obtained in the last 48 hours before delivery. The multiplanar method, using multiple sequential planes with 5.0-mm intervals, was used to calculate fetal upper arm volume. Polynomial regressions were used to determine the best equation in the prediction of fetal weight. The accuracy of this new formula was compared with Shepard's and Hadlock's formulas. RESULTS: fetal upper arm volume was strongly correlated to birth weight (r=0.83; p<0.005). Linear regression was the best equation [birth weight=681.59 + 43.23 x fetal upper arm volume]. The fetal upper arm volume mean error (0 g), mean absolute error (196.6 g) and mean percent absolute error (6.5%) were lower than using Shepard's formula; however, the difference did not reach significance (p>0.05). Birth weight predicted by fetal upper arm volume had a mean error lower than Hadlock's formula, but this difference was not statistically significant (p>0.05). CONCLUSIONS: the accuracy of fetal upper arm volume obtained through 3DUS is similar to the accuracy of bidimensional ultrasound in the prediction of birth weight. These findings need to be confirmed by larger studies.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2008;30(4):190-195
DOI 10.1590/S0100-72032008000400006
PURPOSE: to evaluate the accuracy of fetal upper arm volume, using three-dimensional ultrasound (3DUS), in the prediction of birth weight. METHODS: this prospective cross-sectional study involved 25 pregnancies without structural or chromosomal anomalies. Bidimensional parameters (biparietal diameter, abdominal circumference and femur length) and the 3DUS fetal upper arm volume were obtained in the last 48 hours before delivery. The multiplanar method, using multiple sequential planes with 5.0-mm intervals, was used to calculate fetal upper arm volume. Polynomial regressions were used to determine the best equation in the prediction of fetal weight. The accuracy of this new formula was compared with Shepard's and Hadlock's formulas. RESULTS: fetal upper arm volume was strongly correlated to birth weight (r=0.83; p<0.005). Linear regression was the best equation [birth weight=681.59 + 43.23 x fetal upper arm volume]. The fetal upper arm volume mean error (0 g), mean absolute error (196.6 g) and mean percent absolute error (6.5%) were lower than using Shepard's formula; however, the difference did not reach significance (p>0.05). Birth weight predicted by fetal upper arm volume had a mean error lower than Hadlock's formula, but this difference was not statistically significant (p>0.05). CONCLUSIONS: the accuracy of fetal upper arm volume obtained through 3DUS is similar to the accuracy of bidimensional ultrasound in the prediction of birth weight. These findings need to be confirmed by larger studies.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2006;28(1):38-43
DOI 10.1590/S0100-72032006000100007
PURPOSE: to determine the intraobserver and interobserver reproducibility of endometrial volume measurements using the VOCAL®-imaging program (Virtual Organ Computer-aided AnaLysis). METHODS: one three-dimensional (3-D) ultrasound dataset of the endometrium was obtained from each of five infertile women with different endometrial volumes. For each 3-D dataset, the endometrial volume was calculated by two different observers using the manual mode in four different rotational steps (30º, 15º, 9º and 6º). Ten measurements were obtained with each method and observer from each 3-D dataset. We have used one-way ANOVA and the Tukey post-test to verify the differences among means and the intraclass correlation coefficient to test reliability. RESULTS: rotational methods employing a rotation step of 30º were associated with lower endometrial volume readings in 3 of the 5 patients. There were no significant differences between the means obtained by the 15º, 9º or 6º step rotation. No significant difference was found between the means obtained by the two different observers. The intraclass correlation coefficients were significantly lower with 30º (all under 0.984) than with the other step rotations (all above 0.996). CONCLUSIONS: the use of a rotational step of 15º or less provides reliable readings of endometrial volume: there were no significant differences between the means calculated by the two observers, associated with highintraclass correlation coefficient (>0.996). We recommend the 15º step rotation because it is quicker to be performed than 6º and 9º.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2006;28(1):38-43
DOI 10.1590/S0100-72032006000100007
PURPOSE: to determine the intraobserver and interobserver reproducibility of endometrial volume measurements using the VOCAL®-imaging program (Virtual Organ Computer-aided AnaLysis). METHODS: one three-dimensional (3-D) ultrasound dataset of the endometrium was obtained from each of five infertile women with different endometrial volumes. For each 3-D dataset, the endometrial volume was calculated by two different observers using the manual mode in four different rotational steps (30º, 15º, 9º and 6º). Ten measurements were obtained with each method and observer from each 3-D dataset. We have used one-way ANOVA and the Tukey post-test to verify the differences among means and the intraclass correlation coefficient to test reliability. RESULTS: rotational methods employing a rotation step of 30º were associated with lower endometrial volume readings in 3 of the 5 patients. There were no significant differences between the means obtained by the 15º, 9º or 6º step rotation. No significant difference was found between the means obtained by the two different observers. The intraclass correlation coefficients were significantly lower with 30º (all under 0.984) than with the other step rotations (all above 0.996). CONCLUSIONS: the use of a rotational step of 15º or less provides reliable readings of endometrial volume: there were no significant differences between the means calculated by the two observers, associated with highintraclass correlation coefficient (>0.996). We recommend the 15º step rotation because it is quicker to be performed than 6º and 9º.
