Reference range of fetal transverse cerebellar diameter between 18 and 24 weeks of pregnancy in a Brazilian population

To determine a reference range of fetal transverse cerebellar diameter in Brazilian population. This was a retrospective cross-sectional study with 3772 normal singleton pregnancies between 18 and 24 weeks of pregnancy. The transverse cerebellar diameter was measured on the axial plane of the fetal head at the level of the lateral ventricles, including the thalamus, cavum septum pellucidum, and third ventricle. To assess the correlation between transverse cerebellar diameter and gestational age, polynomial equations were calculated, with adjustments by the determination coefficient (R2). The mean of fetal transverse cerebellar diameter ranged from 18.49 ± 1.24 mm at 18 weeks to 25.86 ± 1.66 mm at 24 weeks of pregnancy. We observed a good correlation between transverse cerebellar diameter and gestational age, which was best represented by a linear equation: transverse cerebellar diameter: -6.21 + 1.307*gestational age (R2 = 0.707). We determined a reference range of fetal transverse cerebellar diameter for the second trimester of pregnancy in Brazilian population.

Aicardi syndrome: Neonatal diagnosis by means of transfontanellar ultrasound

Aicardi syndrome is a rare genetic disease characterized by a characteristic classical trio of neurological clinical abnormalities (spasms), agenesis of the corpus callosum and ophthalmological abnormalities (chorioretinal lacunae). The diagnosis can be suspected by prenatal ultrasound with color Doppler identifying the agenesis of the corpus callosum. Usually, the diagnosis is confirmed in the neonate period by transfontanellar ultrasound and ophthalmological examination. We present a case of newborn with Aicardi syndrome, being the transfontanellar identified partial dysgenesis of the corpus callosum and a cyst in the inter-hemispheric fissure. Ophthalmological examination showed bilateral chorioretinal lacunae.

Reference range for amniotic fluid index measurements in a Brazilian population

OBJECTIVE

The aim of this study was to determine the reference range for amniotic fluid index (AFI) measurements in a large sample of the Brazilian population.

METHODS

This was a retrospective cross-sectional study on 3837 normal singleton pregnancies between 18+0 and 38+6 weeks of pregnancy. The AFI was measured from the largest vertical pockets of amniotic fluid in the four quadrants of the uterine cavity. To assess the correlation between AFI and gestational age (GA), polynomial equations were calculated, with adjustments using the determination coefficient (R2).

RESULTS

The mean maternal age and gestational age were 27.01±6.57 years and 30.43±5.29 weeks, respectively. The mean AFI ranged from 12.2±2.6 cm at 18 weeks to 11.6±6.0 cm at 38 weeks of pregnancy. The correlation between AFI and GA was best represented by a linear equation: AFI=17.78-0.153*GA (R2=0.027).

CONCLUSION

We established the reference range for the AFI in a large sample of the Brazilian population. This reference range can be used to monitor deviations in the volume of amniotic fluid in fetuses at high risk for intrauterine growth disturbances.

Reference charts of fetal biometric parameters in 31,476 Brazilian singleton pregnancies

OBJECTIVES

The purpose of this study was to establish reference charts of fetal biometric parameters measured by 2-dimensional sonography in a large Brazilian population.

METHODS

A cross-sectional retrospective study was conducted including 31,476 low-risk singleton pregnancies between 18 and 38 weeks' gestation. The following fetal parameters were measured: biparietal diameter, head circumference, abdominal circumference, femur length, and estimated fetal weight. To assess the correlation between the fetal biometric parameters and gestational age, polynomial regression models were created, with adjustments made by the determination coefficient (R(2)).

RESULTS

The means ± SDs of the biparietal diameter, head circumference, abdominal circumference, femur length, and estimated fetal weight measurements at 18 and 38 weeks were 4.2 ± 2.34 and 9.1 ± 4.0 cm, 15.3 ± 7.56 and 32.3 ± 11.75 cm, 13.3 ± 10.42 and 33.4 ± 20.06 cm, 2.8 ± 2.17 and 7.2 ± 3.58 cm, and 256.34 ± 34.03 and 3169.55 ± 416.93 g, respectively. Strong correlations were observed between all fetal biometric parameters and gestational age, best represented by second-degree equations, with R(2) values of 0.95, 0.96, 0.95, 0.95, and 0.95 for biparietal diameter, head circumference, abdominal circumference, femur length, and estimated fetal weight.

CONCLUSIONS

Fetal biometric parameters were determined for a large Brazilian population, and they may serve as reference values in cases with a high risk of intrauterine growth disorders.

Reference values of nuchal translucency thickness in a Brazilian population sample: experience from a single center

OBJECTIVE

To determine the reference values of nuchal translucency (NT) thickness at 11-14 weeks of gestation in a sample of the Brazilian population.

METHODS

A retrospective cross-sectional study was carried out with singleton gestations and fetuses with a crown-rump length (CRL) of 45-84 mm. NT thickness was performed according to the guidelines of the Fetal Medicine Foundation (FMF), London, UK. To evaluate the correlation between NT thickness and gestational age (GA), polynomial equations were calculated, with determination coefficient (R2) adjustments, as proposed by Altman-Chitty.

RESULTS

A total of 1420 pregnancies were assessed. The mean of the gestational age was 12.69±0.78 weeks. The mean maternal age was 28.78±6.81 years. The mean NT thickness (mm) for the CRL intervals of 45├50; 50├55; 55├60; 60├65; 65├70; 70├75; 75├80; 80├85 was 1.30±0.74; 1.34±0.60; 1.48±0.48; 1.56±0.68; 1.71±0.67; 1.78±0.69; 1.67±0.43; 1.67±0.58; respectively. The following second-order equation best represented the correlation between NT thickness and GA: NT=-1.2570+0.0765×GA-0.0005×GA2 (R2=0.05).

CONCLUSION

The reference values for NT thickness were determined for a sample of the Brazilian population. Further studies are required to evaluate the real need for including these values in first-trimester screening for chromosomal defects in Brazil.

Reference charts for fetal biometric parameters in twin pregnancies according to chorionicity

OBJECTIVE

The objective of this article is to determine reference values for fetal biometric parameters in twin pregnancies and to compare these values between monochorionic and dichorionic pregnancies.

METHODS

A retrospective cross-sectional study was conducted among 157 monochorionic and 176 dichorionic twin pregnancies between 14 and 38 weeks of gestation. Biometric measurements included the biparietal diameter (BPD), abdominal circumference (AC), femurs length (FL) and estimated fetal weight (EFW). To evaluate the correlation between biometric parameters and gestational age, polynomial regression models were created, with adjustments using the coefficient of determination (R(2) ). Comparison between monochorionic and dichorionic pregnancies was performed using analysis of covariance.

RESULTS

The mean BPD, AC, FL and EFW for the dichorionic pregnancies were 56.16 mm, 191.1 mm, 41.08 mm and 816.1 g, respectively. The mean BPD, AC, FL and EFW for the monochorionic pregnancies were 57.14 mm, 184.2 mm, 39.29 mm and 723.4 g, respectively. There was a statistical difference between mono and dichorionic pregnancies for all the biometric parameters (BPD p = 0.012; AC p = 0.047; FL p = 0.007; EFW p = 0.011).

CONCLUSION

Reference curves of biometric parameters in twin pregnancies were determined. Biometric parameters were statistically different between monochorionic and dichorionic pregnancies.

Normative data for fetal cisterna magna length measurement between 18 and 24 weeks of pregnancy

PURPOSE

The aim of this study was to determine normative data for fetal cisterna magna length (CML) measurement in a Brazilian population.

METHODS

This was a retrospective cross-sectional study on 3,862 normal singleton pregnancies between the 18th and 24th weeks of pregnancy. Fetal CML was measured in the axial plane of the fetal head, at lateral ventricle level, including the cavum septum pellucidum, thalamus, third ventricle, and transverse cerebellar diameter. The anteroposterior measurement was made between the posterior border of the cerebellar vermis and the internal face of the occipital bone. To assess the correlation between CML and gestational age (GA), polynomial equations were calculated, with adjustments using determination coefficient (R2).

RESULTS

The mean CML ranged from 4.29±0.93 mm at 18 to 18+6 weeks to 5.58±1.23 mm at 24 to 24+6 weeks of pregnancy. There was a good correlation between CML and GA, best represented by a linear equation: CML=0.535+0.208*GA (R2=0.084).

CONCLUSION

We established normative data for fetal CML in the second trimester of pregnancy, in a large Brazilian population.

Reference range of fetal nasal bone length between 18 and 24 weeks of pregnancy in an unselected Brazilian population: experience from a single service

OBJECTIVE

To determine reference range of fetal nasal bone length (NBL) during the second trimester of pregnancy in a Brazilian population.

METHODS

This was a retrospective cross-sectional study with 2681 normal singleton pregnancies between 18 and 24 weeks of gestation. The NBL was obtained in the mid-sagittal plane of the fetal face profile using the following landmarks: nasal bone, overlying skin and the tip of the nose. The NBL was measured by placing the calipers in the out-to-out position. To assess the correlation between NBL and gestational age (GA), polynomial equations were calculated, with adjustments by coefficient of determination (R(2)).

RESULTS

The mean of NBL ranged from 5.72 ± 0.87 mm at 18-18 + 6 weeks to 7.45 ± 1.23 mm at 24-24+6 weeks of pregnancy. We observed a good correlation between NBL and GA, best represented by a linear equation: NBL = 0.080+0.276*GA (R(2 )= 0.16).

CONCLUSION

We established a reference range of fetal NBL in the second trimester of pregnancy in a Brazilian population.

Reference intervals of embryos/fetuses heart rate between 6 and 14 weeks of pregnancy

OBJECTIVE

To determine reference intervals for the embryos/fetuses heart rate (HR) between 6 and 14 weeks of pregnancy.

METHODS

A retrospective cross-sectional study was carried in a single center with singleton pregnancies of embryos/fetuses with a crown-rump length (CRL) between 5 and 85 mm. The HR was assessed by real time M-mode or spectrum Doppler ultrasound. To evaluate the correlation between embryo/fetal HR and CRL, polynomial equations were calculated, with adjustment by the determination coefficient (R(2)).

RESULTS

A total of 5867 pregnancies were assessed. The mean gestational age was 10.37 ± 2.12 weeks. The mean maternal age was 26.41 ± 6.78 years. The mean embryo/fetal HR (bpm) for the CRL (mm) intervals 5├15; 15├25; 25├35; 35├45; 45├55; 55├65; 65├75; 75├85 was 145.1 ± 18.7; 167.2 ± 10.1; 166.9 ± 8.7; 165.5 ± 6.9; 162.2 ± 6.8; 159.2 ± 6.4; 157.1 ± 6.4; 154.9 ± 7.3; respectively. The following third-order equation best represented the correlation between embryo/fetal HR and CRL: HR = 119.25 + 3.596*CRL-0.07954*CRL(2 )+ 0.00051*CRL(3) (R(2 )= 0.36).

CONCLUSION

Reference intervals of HR in embryos/fetuses in a large sample were determined. These reference intervals can be used in high-risk early pregnancy losses.

Magnetic resonance imaging vs. transvaginal ultrasound for cervical length assessment in the second half of pregnancy

The purpose of this cross-sectional study involving 42 women between 20 and 39 weeks gestation was to compare transvaginal ultrasound (TVUS) vs. magnetic resonance imaging (MRI) in the assessment of cervical length measurement during the second half of pregnancy and to evaluate the reproducibility of cervical measurements obtained through MRI. Cervical length was measured through TVUS by a single examiner. On the same day, all women also had MRI and cervical length was assessed by two independent blinded observers. There were no significant differences in the mean cervical length obtained through TVUS and MRI (paired t-test, p = 0.191). The Bland-Altman test indicated concordance between measurements obtained through methods as well as good intra- and interobserver reproducibility for MRI measurements. Intraclass correlation coefficient was 0.990 (95% confidence interval [CI]: 0.982 to 0.995; p < 0.001) for measurements performed using MRI by two different observers and 0.995 (95% CI: 0.991 to 0.997; p < 0.001) for measurements performed using the same method by a single operator. Cervical length measured through TVUS and MRI does not differ significantly. There is a good reproducibility of cervical measurements obtained through MRI.

Correlation of the fetal cerebellar volume with other fetal growth indices by three-dimensional ultrasound

OBJECTIVE

To verify the correlation of fetal cerebellar volume by three-dimensional ultrasound (3D US) with other indices of fetal growth in normal fetuses.

METHODS

This was a longitudinal prospective study involving 52 normal pregnant women between 20 and 32 weeks of gestation. The assessments of the fetal cerebellar volume were carried out at intervals of two weeks, and the method used was VOCAL (virtual organ computer-aided analysis) with a 30 degrees rotation angle. At each assessment, the following biometric indices were evaluated using the two-dimensional method: biparietal diameter, head circumference, transverse cerebellar diameter, femur length, and estimated fetal weight. We used Pearson's correlation coefficient to evaluate the correlation between fetal cerebellar volume and these indices; we also used polynomial regression analysis with fetal cerebellar volume as the dependent variable and the other indices as the independent variable.

RESULTS

The fetal cerebellar volume was highly correlated with gestational age (r = 0.94; p < 0.001) and with all other fetal growth indices (p < 0.001).

CONCLUSIONS

The assessment of the fetal cerebellar volume by 3D US is an important tool to evaluate fetal growth.

Avaliação biométrica do colo uterino durante a gestação por meio da ultra-sonografia transvaginal e ressonância magnética

OBJETIVO: Avaliar o comprimento do colo uterino por meio da ressonância magnética e comparar aos achados da ultra-sonografia transvaginal. MATERIAIS E MÉTODOS: Foram realizados exames ultra-sonográficos e de ressonância magnética do colo uterino em 20 pacientes com idade gestacional entre 19 e 30 semanas. As medidas do colo obtidas pelo exame de ressonância magnética foram aferidas por dois especialistas em diagnóstico por imagem, para calcular a variabilidade interobservador do método. RESULTADOS: O cálculo do coeficiente de correlação de Pearson entre as medidas do comprimento cervical indicou correlação significante entre os métodos (r=0,628; p<0,01). A aplicação do teste t pareado não evidenciou diferença significativa entre as medidas aferidas pela ultra-sonografia transvaginal e ressonância magnética (p=0,068). A análise da variabilidade interobservador das medidas do colo obtidas pela ressonância magnética demonstrou alta confiabilidade do método (a=0,96). CONCLUSÃO: A comparação entre os dois métodos de imagem na avaliação da biometria cervical não apresentou diferença estatística, o que reforça a aplicação do exame ultra-sonográfico. Entretanto, em situações nas quais a ultra-sonografia transvaginal apresenta contra-indicações, o exame de ressonância magnética poderá apresentar-se como segunda opção para a avaliação do comprimento cervical.

Doppler assessment of uterine blood flow in recurrent pregnancy loss

OBJECTIVE

To compare uterine artery pulsatility index (PI) and flow velocity wave (FVW) patterns between women with no history of abortion and women with recurrent pregnancy loss of unexplained cause.

METHOD

A cross-sectional study was conducted with 43 women with recurrent pregnancy loss and 43 women with no history of abortion and at least 1 child born at term (control group). Transvaginal ultrasonography with uterine artery Doppler evaluation was performed in the second phase of the menstrual cycle to calculate the PI and analyze the FVW pattern.

RESULTS

The women with recurrent pregnancy loss had a significantly higher uterine artery PI than those in the control group (2.71+/-0.54 and 2.30+/-0.44, respectively), as well as a higher incidence of FVWs of the A and B types.

CONCLUSION

Compared with the control group, a higher PI and a higher incidence of FVW of the A and B types--and thus a higher uterine artery impedance--were found among women with recurrent pregnancy loss.

Sonoembryology by three-dimensional ultrasonography: pictorial essay

CONTEXT

Three-dimensional ultrasonography in obstetrics has evolved in the last years, and nowadays it is a methodology that greatly helps prenatal diagnosis. Through its rendering mode it allows the careful evaluation of fetal face and limbs, and in multiplanar mode it allows the assessment of the anatomy through the many possible planes. In the first trimester of gestation, three-dimensional ultrasonography permits the detailed evaluation of embryonic development. Its main advantages over two-dimensional ultrasonography are shorter examination time and the possibility of storage of the volumes for later processing and analysis.

AIM

We present a pictorial essay with normal embryo development in the first trimester of pregnancy by three-dimensional ultrasonography, from the fifth to ninth week.

Ultra-sonografia tridimensional do colo uterino na gestação: perspectivas

A medida do comprimento cervical por ultra-sonografia transvaginal é útil no rastreamento do parto prematuro, sendo o encurtamento do colo fator preditor do trabalho de parto pré-termo. Os métodos tradicionais para avaliar a cérvice na gestação são limitados e insatisfatórios. O exame de toque digital, considerado método padrão, demonstra variação entre diferentes examinadores, entretanto, a ultra-sonografia transvaginal é exame eficiente durante a gravidez. Recentemente, o exame ultra-sonográfico tridimensional tem sido utilizado na prática clínica, incluindo o estudo do colo. Grande volume de informações pode ser obtido e armazenado utilizando-se a tecnologia tridimensional. A informação armazenada permite ser manipulada e analisada por número infinito de planos. O exame ultra-sonográfico transvaginal tridimensional é o único capaz de obter o plano coronal pela visualização da imagem em organização multiplanar. Este método aparenta oferecer potencial diagnóstico no aumento da acurácia da ultra-sonografia cervical.

Cervical gland area as an ultrasonographic marker for preterm delivery

OBJECTIVE

To assess the association between spontaneous preterm delivery (SPTD) in the general population and the measurement of the cervix length, cervical funneling, and absence of the cervical gland area (CGA).

METHOD

A prospective cohort of 338 women carrying uncomplicated pregnancies was evaluated by transvaginal sonography between 21 and 24 weeks' gestation.

RESULTS

Measurement of cervical length with less than 20 mm and the presence of cervical funneling presented a statistically significant association with SPTD before 35 weeks. The non-detection of CGA demonstrated a strong association with SPTD before 37 weeks' (p < 0.001; OR = 194.5) and before 35 weeks' gestation (p < 0.001; OR = 129.6). The multiple logistic regression analysis suggested the non-detection of CGA as the only variable to reveal statistically significance association with SPTD.

CONCLUSION

The results seem to indicate that the absence of CGA can be a new and important ultrasound marker for SPTD, to be confirmed by future multicenter investigations.

Prenatal diagnosis of vasa previa through color Doppler and three-dimensional power Doppler ultrasonography. A case report

Vasa previa occurs in pregnancy when one of the membrane vessels extends down to the level of the internal cervical os, ahead of the fetal presenting part and unsupported by the placenta tissue or umbilical cord. The rupture of the vessels might happen spontaneously or artificially and frequently results in fetal exsanguination and demise. Ultrasound prenatal diagnosis is highly important as it allows the identification of patients at risk, thus an elective cesarean can be performed before rupture the membranes. We report a case of vasa previa diagnosed through color Doppler mode in the 30th week of gestation, emphasizing the contribution of three-dimensional power Doppler to the adequate mapping of aberrant vessels, which greatly contributed to the success of the perinatal result.

True hermaphroditism-the importance of ultrasonic assessment

Intersex states are associated with rare syndromes within a wide clinical spectrum, true hermaphroditism being the rarest of them all. It is a condition that is characterized by ovotestis, i.e. the presence of ovarian and testicular tissues in the same individual, either in separate gonads or in the same gonad. Diagnostic investigation of hermaphroditism involves ultrasound examination of the gonads, karyotype analysis and histological studies. We report the case of a 21-year-old individual with true hermaphroditism, in whom ovotestis was diagnosed on ultrasonography and which was later confirmed by anatomopathological study of the gonads. The role of ultrasound in the initial diagnostic investigation of intersex states, especially true hermaphroditism, is discussed.

Estudo comparativo entre marcadores ultra-sonográficos morfológicos preditores de parto pré-termo: sinal do afunilamento do colo e ausência do eco glandular endocervical

OBJETIVO: Avaliar o risco de parto pré-termo (PPT) espontâneo na população geral a partir do estudo comparativo dos marcadores ultra-sonográficos morfológicos do colo uterino, como o sinal do afunilamento e a ausência da área glandular endocervical. MATERIAIS E MÉTODOS: Foram arroladas 361 gestantes na população geral, submetidas a exame ultra-sonográfico transvaginal entre a 21ª e 24ª semana, e verificados os resultados perinatais. RESULTADOS: A incidência de PPT espontâneo foi de 5,0%. O sinal do afunilamento foi observado em 4,2% da população estudada e em 22,2% das pacientes que evoluíram para PPT espontâneo. Tal parâmetro mostrou associação significante com PPT (p < 0,001; risco relativo de 6,68). A ausência do eco glandular endocervical (EGE) foi detectada em 2,8% das pacientes estudadas e em 44,4% das pacientes que evoluíram para PPT espontâneo. Este parâmetro demonstrou forte associação com PPT espontâneo (p < 0,001; risco relativo de 28,57). A análise de regressão logística multivariada apontou a ausência do EGE como a única variável morfológica associada ao PPT espontâneo. CONCLUSÃO: A predição do PPT espontâneo a partir de sinais ultra-sonográficos deve ser realizada contemplando marcadores biométricos e morfológicos, entre estes, a ausência do EGE. Este estudo indica uma tendência clara da marcante importância da ausência do EGE como indicador do risco para PPT espontâneo, a ser confirmada futuramente em pesquisas multicêntricas.

[Assessment of intestinal permeability using 51 CrEDTA: clinical usefulness in the detection of small bowel epithelial structural abnormalities]

Intestinal permeability tests have been increasingly used in the clinical management of small bowel diseases. Nevertheless, the application of such tests in Brazil is still limited. In this study we report the results of the application of 51Cr-EDTA for assessment of intestinal permeability in 13 healthy volunteers, 10 control patients with miscellaneous disorders, but without evidence of small bowel involvement, 11 patients with well characterized diseases affecting the small bowel, and five patients with inflammatory conditions affecting exclusively the colon. Urinary radioactivity levels in the 24 h following the ingestion of 51Cr-EDTA, expressed as the percentage of the ingested dosis, ranged from 1.99 to 5.93% (median: 3.14%) in healthy volunteers and was not significantly different from the results obtained in control patients (range: 1.48-3.98%; median 3.32%). Based on data from these two control groups, an upper limit of the normal range was set at 5.17% (95% confidence interval). Among patients with diseases of the small bowel, results ranged from 1.58 to 14.85% (median: 8.07%) and were significantly different from those observed in the control groups. Only two out of the 11 patients in this group had abnormal results. In the group of patients with diseases of the colon, results ranged from 3.48 to 5.13% (medium: 4.54%) and were not significantly different from the results obtained in control subjects. All patients in this group had results within the normal range. Data from control subjects and patients with diseases of the small bowel were used for the calculations of sensitivity (81%), specificity (96%), as well as false-positive (4.3%) and false-negative (18.1%) rates. Taken as a whole, the results of the present study indicate that the 51Cr EDTA test of intestinal permeability is accurate and may be useful in the clinical management of small bowel diseases in Brazilian patients.

Mono and polichemotherapy in the treatment of metastatic and invasive gestational trophoblastic disease: analysis of 50 cases

Fifty patients with metastatic or invasive gestational trophoblastic disease (GTD) were admitted at the "Hospital das Clínicas" of the Ribeirão Preto School of Medicine of the São Paulo University between January 1980 and December 1990. Of these 50 patients, 44 (88%) had GTD following abortion, 5 (10%) after term pregnancies and one (2%) after an ectopic pregnancy. Thirty five (70%) had invasive GTD and 15 (30%) metastatic GTD. The sites of metastases were: lung, 8 (53.3%), pelvis, 4 (26.6%), central nervous system, 2 (13.3%) and right auricle, 1 (6.6%). Human chorionic gonadotropin, pelvic arteriography and ultrasonography were used in the diagnosis of invasive GTD. 25 of the 41 patients with low-risk metastatic and invasive GTD were treated with monochemotherapy. There were 6 (24%) failures and the remaining 19 patients (76%) had complete remission of the disease after 2.89 mean cycles. Sixteen patients were treated with polichemotherapy, there were 2 (12.5%) failures and the remaining 14 had complete remission after a 2.3 mean cycles. No statistical differences between the two types of chemotherapy were observed. Four (8%) deaths were recorded.