Assessment of lower limb trophism in fetuses with open spina bifida using fractional thigh volume of three-dimensional ultrasound.

OBJECTIVE: To assess the trophism of the lower limbs of fetuses with open spina bifida using fractional thigh volume (TVOL) of three-dimensional (3D) ultrasound. METHODS: A prospective cross-sectional study was carried out with normal fetuses and with open spina bifida (myelomeningocele and rachischisis) at 26 weeks' gestation. The TVOL (delimitation of five cross-sectional areas of the middle portion of the limb) was evaluated, as well as the subjective assessment of hypotrophy and lower limb movement. RESULTS: Thirty-one fetuses with open spina bifida, 21 with myelomeningocele and 10 with rachischisis, and 51 normal fetuses were included. There were no significant differences in the TVOL between normal and spina bifida fetuses (p = 0.623), as well as between normal fetuses, with myelomeningocele and with rachischisis (p = 0.148). There was no significant difference in the TVOL of fetuses with spina bifida with or without lower limb hypotrophy (p = 0.148). Fetuses with spina bifida and with lower limb movement had higher TVOL values than fetuses without lower limb movement (p = 0.002). CONCLUSION: There were no significant differences in the TVOL measurement of normal and spina bifida fetuses (rachischisis and myelomeningocele). Fetuses with spina bifida without spontaneous movement of the lower limbs had lower TVOL values.

Prenatal diagnosis of closed spina bifida: multicenter case series and review of the literature.

Objective: Closed spina bifida (CSB) is an abnormality of the posterior arch formation in which the defect is covered by the skin, without protrusion of nervous tissue. The prenatal diagnosis of CSB is very difficult, rarely diagnosed antenatally.Methods: We present a multicenter case series of six prenatal diagnosis of CSB using two-dimensional (2D) ultrasonography complemented with three-dimensional (3D) ultrasonography and magnetic resonance imaging (MRI). All cases of prenatal diagnosis of CSB were confirmed in the postnatal period/termination of pregnancy by both clinical and/or imaging diagnosis (ultrasonography and MRI).Results: 2D ultrasonography allowed the prenatal diagnosis of six cases. We observed two cases of subcutaneous lipomas, two cases of meningoceles, one case of fibrolipomas, and one case of false-positive CSB (meningomyelocele). 3D ultrasonography using rendering mode was important in one case of meningocele (case# 3). Three cases were delivered at term and one of them was submitted to corrective surgery. All these three newborns were discharged from the hospital well and without neurologic signs. Termination of pregnancy was performed in three cases.Conclusion: During prenatal evaluation, detailed ultrasonographic assessment of the entire spine with the identification of the position and morphology of the conus medullaris and absence of cranial signs of spinal dysraphism are the most valuable sonographic clues for the diagnostic of the CSB.

Ultrasonographic evaluation of the fetal central nervous system: review of guidelines.

Central nervous system malformations constitute the second most common group of anomalies in fetuses. Such malformations have assumed clinical importance because of their association with high rates of perinatal morbidity and mortality. Therefore, it is extremely important to assess the fetal central nervous system during the prenatal period, in order to identify any changes in its development and thereby gain sufficient information to advise parents about pregnancy follow-up, options for fetal therapy, and the timing/type of delivery, as well as the postnatal treatment and prognosis. The objective of this review was to describe the ultrasonographic evaluation of the fetal central nervous system as per the guidelines of the International Society of Ultrasound in Obstetrics and Gynecology.

Malformações do sistema nervoso central são o segundo mais frequente grupo de anomalias que afetam o feto. Elas têm adquirido grande importância em razão da sua associação com altas taxas de morbidade e mortalidade perinatal. Além do mais, é extremamente importante avaliar o sistema nervoso central fetal durante o período pré-natal, de modo a se diagnosticar possíveis mudanças no desenvolvimento e aconselhar os casais sobre o seguimento da gestação, possibilidades terapêuticas fetais, tempo e tipo de parto, tratamento pós-natal e prognóstico. O objetivo desta revisão foi descrever a avaliação do sistema nervoso central fetal por meio das recomendações da International Society of Ultrasound in Obstetrics and Gynecology.

Fetal posterior fossa malformations: review of the current knowledge.

Ultrasound diagnosis of posterior fossa malformations in the prenatal period is a challenge, having major implications for the counseling and follow-up of pregnant women. The purpose of this study was to review aspects of the ultrasound evaluation of the fetal posterior fossa, as well as to describe the most relevant ultrasound findings of the main posterior fossa malformations that can affect the fetus in the prenatal period.

Cerebellar herniation demonstrated by the occipitum-dens line: Ultrasonography assessment of normal fetuses, fetuses with myelomeningocele, and fetuses that underwent antenatal myelomeningocele surgery.

OBJECTIVE: To establish a method to quantify the position of the cerebellum by ultrasonography in normal fetuses, fetuses with myelomeningocele (MMC), and fetuses that underwent in utero MMC repair. METHODS: Reference points identifiable on ultrasound were established. The basilar portion of the occipital bone and upper portion of the odontoid process were considered as the external and internal limits, respectively, of the level zero of a line that was designated the occipitum-dens line (ODL). Eighty-three normal fetuses were assessed 1 occasion (cross-sectional study) in addition to 25 fetuses with MMC and 25 fetuses that underwent in utero MMC repair. The groups were compared using analysis of variance or the Kruskal-Wallis test. The intraclass correlation coefficient (ICC) was used to determine intra- and interobserver reproducibility. RESULTS: The analysis of ODL indicated that all normal fetuses had the cerebellar tonsil above level zero at a mean distance of 2.8 ± 1.1 mm (P = 0.125). The fetuses with MMC had the cerebellar tonsil below level zero, except in 2 cases of myelocystocele. All the fetuses that underwent in utero MMC repair exhibited regression of the cerebellar herniation (0.5 mm per week, P < 0.005). Herniation increased gradually (1.0 mm per week, P < 0.005) in fetuses that did not undergo MMC repair. ICC indicated good intra- and interobserver reproducibility (0.996 and 0.983, respectively). CONCLUSION: The reference points for ODL may be used to assess cerebellar height. ODL allowed the demonstration of the regression of cerebellar herniation in fetuses that underwent in utero MMC repair.

New technique for assessing fetal heart growth using three-dimensional ultrasonography: description of the technique and reference curves.

OBJECTIVE: To describe a new technique for assessing fetal growth using three-dimensional ultrasonography (3DUS) using the extended imaging virtual organ computer-aided analysis (XI VOCAL) software and its respective reference curves. METHODS: We conducted a cross-sectional study on 303 normal singleton pregnancies between their 20th and 34th weeks. To assess fetal heart growth, we used the XI VOCAL software with 10 planes in which the reference lines (beginning and end) were placed at the cardiac apex, the output level of the vessels and the base above the diaphragm, respectively. To assess the correlation between distance and interval, polynomial regressions were performed with adjustments using the coefficient of determination (R(2)). To assess the inter-observer reproducibility, we used the intraclass correlation coefficient (ICC). RESULTS: The mean distance between the apex and the base of the fetal heart ranged from 14.41 ± 1.24 mm to 26.24 ± 2.62 mm between the 20th and 34th weeks, respectively. The mean interval between the apex and the base of the fetal heart ranged from 1.56 ± 0.13 mm and 2.94 ± 0.30 mm between the 20th and 34th weeks, respectively. We observed good correlation of distance and interval with the gestational age, with R(2) = 0.73 and 0.74, respectively. We observed a good inter-observer to the interval and distance with ICC = 0.983 and 0.996, respectively. CONCLUSION: We described a new technique for assessing fetal heart growth using 3DUS and determined reference curves for the distance and interval between the 20th and 34th weeks of pregnancy.

Reference intervals for fetal heart volume from 3-dimensional sonography using the extended imaging virtual organ computer-aided analysis method at gestational ages of 20 to 34 weeks.

OBJECTIVES: The purpose of this study was to establish the reference range for fetal heart volume from 3-dimensional (3D) sonography using the extended imaging virtual organ computer-aided analysis method. METHODS: The fetal heart volume was measured in 303 normal singleton pregnancies at gestational ages of 20 to 34 weeks using 3D sonography. The extended imaging virtual organ computer-aided analysis method was used to obtain a sequence of 10 parallel symmetric sections through the heart, according to examiner-determined limits (the apex at one extremity and the connection to the great vessels at the other). Heart contours were drawn manually in all sections to obtain the 3D volume measurement, which was provided automatically by the software. Normal z scores and percentile reference ranges for each gestational age were constructed. RESULTS: The fetal heart volume increased with gestational age. The mean values were 3.09 mL at 20 weeks, 9.18 mL at 26 weeks, and 24.89 mL at 34 weeks, according to the following formulas: fetal heart volume (mL) = 18.0076 - 2.1005 × gestational age + 0.0677 × gestational age2 (R(2) = 0.922); and SD (mL) = (4.5038 - 0.4281 × gestational age + 0.0114 × gestational age2) × âˆš1.495808 (R(2) = 0.922). CONCLUSIONS: A reference range for fetal heart volume using the 3D sonographic extended imaging virtual organ computer-aided analysis method at gestational ages of 20 to 34 weeks was established.

Análise da reprodutibilidade do Doppler de amplitude tridimensional na avaliação da circulação do cérebro fetal / Analysis of three-dimensional power Doppler sonography reproducibility in the assessment of fetal brain circulation

OBJETIVO: Avaliar a reprodutibilidade intra e interobservador do Doppler de amplitude tridimensional (3D power Doppler) na avaliação do fluxo sanguíneo cerebral do território da artéria cerebral média. MATERIAIS E MÉTODOS: Foi realizado estudo transversal com 20 gestantes normais entre 26 e 34 semanas. O território da artéria cerebral média mais próximo ao transdutor foi selecionado e o volume foi calculado utilizando-se o método Virtual Organ Computer-aided AnaLysis. Posteriormente, obtiveram-se os índices do 3D power Doppler: índice de vascularização (VI), índice de fluxo (FI) e índice de vascularização-fluxo (VFI). Utilizaram-se, para os cálculos, o coeficiente de correlação intraclasse (CCI) e gráficos de Bland-Altman. RESULTADOS: Foi observada boa concordância intra e interobservador, com CCI > 0,90 para todos os índices do 3D power Doppler: VI [CCI = 0,992 (IC 95 por cento: 0,981-0,997)], FI [CCI = 0,999 (IC 95 por cento: 0,998-0,999)], VFI [CCI = 0,995 (IC 95 por cento: 0,987-0,998)]. Reprodutibilidade interobservador: VI [CCI = 0,988 (IC 95 por cento: 0,970-0,995)], FI [CCI = 0,999 (IC 95 por cento: 0,997-1,000)], VFI [CCI = 0,994 (IC 95 por cento: 0,994-0,998)]. CONCLUSÃO: O 3D power Doppler mostrou-se um método prático, fácil e com boa reprodutibilidade intra e interobservador, com o IF evidenciando a melhor concordância intra e interobservador.

OBJECTIVE: To evaluate the intra- and interobserver reproducibility of three-dimensional power Doppler sonography (3D power Doppler) in the assessment of fetal brain blood flow in the middle cerebral artery territory. MATERIALS AND METHODS: A cross-sectional study was developed with 20 healthy pregnant women between 26 and 34 gestational weeks. The middle cerebral artery territory closest to the transducer was scanned and the blood flow volume was calculated with the method Virtual Organ Computer-aided AnaLysis. The following 3D power Doppler indices were later obtained: vascularization index (VI), flow index (FI) and vascularization-flow index (VFI). The intraclass correlation coefficient (ICC) and Bland-Altman plots were utilized for calculating the intra- and interobserver variability. RESULTS: A good intra- and interobserver agreement was observed, with ICC > 0.90 for all the 3D power Doppler indices: VI [ICC = 0.992 (CI 95 percent: 0.981-0.997)], FI [ICC = 0.999 (CI 95 percent: 0.998-0.999)], VFI [ICC = 0.995 (CI 95 percent: 0.987-0.998)]. Interobserver reproducibility: VI [ICC = 0.988 (CI 95 percent: 0.970-0.995)], FI [ICC = 0.999 (CI 95 percent: 0.997- 1.000)], VFI [ICC = 0.994 (CI 95 percent: 0.994-0.998)]. CONCLUSION: 3D power Doppler has shown to be a practical and easy method in the assessment of fetal brain blood flow, with good intra- and interobserver reproducibility. The FI presented the best intra- and interobserver agreement.

Reliability and validity of in vitro volume calculations by 3-dimensional ultrasonography using the multiplanar, virtual organ computer-aided analysis (VOCAL), and extended imaging VOCAL methods.

OBJECTIVE: The purpose of this study was to assess the reliability and validity of in vitro volume calculations by 3-dimensional ultrasonography. METHODS: This observational study was performed by 2 examiners to obtain volumes of 3 objects of different shapes and sizes filled with ultrasound gel and immersed in water. The examiners used the multiplanar (5-mm interval), virtual organ computer-aided analysis (VOCAL, 30 degrees) and extended imaging (XI) VOCAL (5, 10, 15, and 20 planes) methods to estimate the volumes of each object. A paired Student t test (P) and intraclass correlation coefficients (ICCs) were used to assess reproducibility of the methods. Validity was assessed comparing the percent differences between the estimated and the real volumes using the P value, mean differences, and ICC for each method. RESULTS: All methods were highly reliable and valid. There were no significant differences in interobserver variability; there was a strong interobserver correlation. There were no significant differences in the percent differences between the estimated and real volumes of the objects using the 3 methods. The XI VOCAL method was superior to the multiplanar and VOCAL methods in the measurement of irregularly shaped objects. The XI VOCAL method with 10 planes estimated volumes closest to the real volumes. CONCLUSIONS: All 3 methods were reliable and valid; however, XI VOCAL was superior to the other methods in the measurement of irregularly shaped objects.