Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2006;28(3):151-157
DOI 10.1590/S0100-72032006000300003
PURPOSE: the absence of fetal nasal bone is correlated with trisomy 21. Although a hypoplastic nasal bone is also correlated with trisomy 21, there is no clear definition of this term in the literature. Our objective was to establish the reference values for fetal nasal bone size throughout gestation in a local population in Brazil. METHODS: it is a cross-sectional study on 902 fetuses at 10 to 39 weeks of gestation. After having excluded fetal malformations and maternal diseases which are known to interfere with fetal growth, 625 fetuses were selected. We obtained a mid-sagittal view of the fetal profile by holding the ultrasound bean at an angle of 45º or 135º. The nasal bone size mean was calculated by using polynomial regression. The Anderson-Darling test proved the normal distribution of the measurements (p>0.05). RESULTS: of the 625 fetuses, 88.3% were from single gestations and 11.7% from multiple ones. There was a direct correlation between fetal nasal bone size and gestational age. The variability of nasal bone size became larger as gestational age increased. Minimal length of 1.0 and 4.7 mm in the first and second trimesters, respectively, were found. CONCLUSIONS: there is a direct correlation between fetal nasal bone size and gestational age. This correlation is valid either for a single gestation or a multiple one. These measurements of the fetal nasal bone will allow us to use them as a screening test for cromosomal abnormalities. This is a useful study if we consider the large miscegenation of the Brazilian population. However, further systematic and standardized approach to study the fetal nasal bone is needed to establish its real value in fetuses once classified as at high or low risk for aneuploidies.
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. 2005;27(12):750-758
DOI 10.1590/S0100-72032005001200008
Congenital cytomegalovirus infection is an important clinical entity, due to its sonographic symptomatology. In Brazil, in utero diagnosis is not accomplished despite the improvements in diagnostic methods. We report a congenital infection including: splenomegaly and hepatomegaly, hypoplasia of the cerebellar vermis, intracranial calcifications, hyperechoic kidneys, hyperechoic bowel, cardiomegaly, lung hypoplasia, ascites, and pericardial effusion. Fetal magnetic resonance imaging confirmed the sonographic findings. Amniocentesis was performed for cytomegalovirus PCR in amniotic fluid, which confirmed fetal infection. Fetal loss occurred in the 31st week of pregnancy. Necropsy studies confirmed the sonographic findings. The diagnostic methods have been useful to confirm congenital cytomegalovirus infection and to establish fetal outcome.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2005;27(9):515-523
DOI 10.1590/S0100-72032005000900003
PURPOSE: the technological improvements in image quality have increased the importance of ultrasound as an imaging method in the study of breast pathologies. The need for a standardized method for lesion characterization, description and reporting in image analysis motivated the development of a breast sonographic report classification system. METHODS: the classification grouped the breast sonographic images in five classes: I - normal; II - benign; III - indeterminate, IV - suspect, and V - highly suspect. The used morphologic ultrasound features were shape, border, contour, echogenicity, echotexture, sound transmission, orientation, and secondary signals. The gold standard test, in the study of 450 lesions, considered sonographic follow-up of the lesions for a period from 6 to 24 months and the histopathology of surgical cases. RESULTS: breast sonographic classification for the diagnosis of breast cancer showed a sensitivity of 90.2% (CI: 82.8-94.9%), a specificity of 96.2% (CI: 94.0-97.6%), a positive predictive value of 84.1% (CI: 76.0-89.9%), and a negative predictive value of 97.8% (CI: 95.9-98.9%), obtaining an accuracy of 95.1%. CONCLUSIONS: the adoption of a sonographic classification system results in the standardization and optimization of the reports. It also aids the comparison with clinical findings, histopathological tests and breast images, avoiding unnecessary procedures and therefore leading to more adequate therapeutical management.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 1999;21(10):569-576
DOI 10.1590/S0100-72031999001000002
Purpose: to estimate growth curves and tables of average biparietal diameter and average head circumference of twin gestations and to compare them with published growth curves for singletons and twins. Methods: growth curves and tables of average biparietal diameter and average head circumference were obtained from sonographic examinations of 34 patients with twin gestations without maternal and fetal complications. Sonographic examinations were performed each 2 or 3 weeks by a single observer. The parameters were compared with existing growth curves for singletons and twins. Results: curves and tables of biparietal diameter and head circumference in relation to gestational age were obtained. The study revealed difference in growth pattern mainly regarding the 3rd trimester in relation to singletons (Hadlock et al.15). The difference between the average values were 6 mm (biparietal diameter) and 2.0 cm (head circumference) at the 39th week of gestation. Also, some differences were observed relative to the twin studies. Conclusion: this study revealed that growth curves for average biparietal diameter and average head circumference of singletons are not appropriate to determine gestational age in twin gestations of the studiced population principally at the 3rd trimester
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2005;27(8):450-455
DOI 10.1590/S0100-72032005000800003
PURPOSE: to test a new, noninvasive method for the diagnosis of fetal anemia in red blood cell isoimmunized pregnancies. METHODS: the index obtained by the ratio between the ultrasonographic measurement of the biventricular outer dimension (BVOD) and femur length (both in centimeters) was correlated with fetal hemoglobin values in a cross-sectional study. Fifty-nine fetuses of isoimmunized pregnancies selected for invasive treatment and submitted to 130 cordocenteses for the diagnosis and treatment of anemia were included in the study. The cardiofemoral index was obtained immediately before the cordocentesis and the fetal hemoglobin index was obtained from fetal blood samples. Linear regression was carried out to assess the correlation between the index and fetal hemoglobin; ROC curve was applied to determine the most accurate cutoff for the diagnosis of the fetal hemoglobin concentration below 10g/dl. RESULTS: BVOD measurement varied from 1.6 to 4.7 cm (average 2.5±1.3cm), and length of the femur, from 3.0 to 6.9 cm (average 4.3±0.9 cm). The cardiofemoral index varied from 0.4 to 1.0 (average 0.6±0.1). A significant inverse correlation between the cardiofemoral index and fetal hemoglobin (R²=0.37 and p<0.0001) was observed. The cutoff of 0.60 was the best to predict a level of fetal hemoglobin below or equal to 10.0g/dl: 80.85% sensitivity, 83.13% specificity, 73.8% positive predictive value, and 88.46% negative predictive value, in the diagnosis of fetuses anemia. CONCLUSION: the cardiofemoral index allows for good accuracy in the prediction of fetal hemoglobin concentration below 10g/dl in red blood cell isoimmunized pregnancies. It may thus be applied as a noninvasive method to the diagnosis of this pathology.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2000;22(5):281-286
DOI 10.1590/S0100-72032000000500005
Purpose: to evaluate the effectiveness of the transverse cerebellar diameter (TCD), by ultrasonography, in the evolution of the fetal growth, and to relate it to gestational age, biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur length (FL). Method: a prospective and longitudinal study was performed on 254 pregnant women considered of low risk, with a gestational age from 20 to 40 weeks. Only 55 pregnant women were included in the study, according to inclusion and exclusion criteria. All the examinations, 217 ultrasonographic evaluations, were done by the author (LN), at least three and at most six examinations for each pregnant woman being accomplished at an interval of one to five weeks. Normality patterns were established between the 10 and 90 percentiles for each gestational age and confirmed postnatally. Results: the transverse cerebellar diameter presented a good correlation with the gestational age either as a dependent variable (R² = 0.90) or as an independent variable (R² = 0.92). A significant relationship was found in the evaluation of the fetal growth between the TCD and the several fetal parameters: BPD and HC (R² = 0.92), FL (R² = 0.90) and AC (R² = 0.89). Conclusions: the transverse cerebellar diameter is a parameter that should be used in the follow-up of development and of fetal growth because of the ascending pattern of its growth curve. Any up- or downward alteration in the growth curve can be useful for the detection of deviations of fetal growth.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2004;26(5):377-382
DOI 10.1590/S0100-72032004000500006
OBJECTIVE: to describe ultrasonographic alterations in fetuses infected with Toxoplasma gondii, correlating them with neonatal prognosis. METHODS: between June 1997 and May 2003, 150 pregnant women with suspected toxiplasmosis were examined. Acute infection was confirmed in 72 (48%) of these pregnant women and congenital toxoplasmosis was diagnosed in 12 (16%) fetuses. Prenatal diagnosis was established by polymerase chain reaction in the amniotic fluid. All the patients received antiparasitic therapy. Ultrasound examination was performed every fortnight and all the infants were evaluated during their first year of life. RESULTS: ultrasonographic changes were observed in eight fetuses. All of them showed symmetric bilateral ventricular enlargement that was associated with periventricular calcifications in five cases. Other changes as hepatic calcification, hepatomegaly, polyhydramnium, and pericardial effusion were less frequent. Among these fetuses, four were stillborn and three showed sequelae (chorioretinitis and neuro-psychomotor retardation). The four fetuses that showed normal ultrasonography had a satisfactory development. CONCLUSION: There was a high incidence of ultrasonographic changes in fetuses with congenital toxoplasmosis, mainly brain damage. Other changes as hepatomegaly and pericardial effusion were less frequent and were related to a systemic infection. The prognosis of these fetuses seems to be correlated with the presence of these lesions mainly because they had high mortality ratio and among the survivors the incidence of sequelae was high. The non-symptomatic fetuses evolved in a favorable way without developing sequelae. These results highlight the value of ultrasonographic examination of these fetuses in order to establish a prognosis and allow the elaboration of a suitable post-natal procedure.