The 'Brain Shadowing Sign': A Novel Marker of Fetal Craniosynostosis.

INTRODUCTION: The prenatal diagnosis of fetal craniosynostosis is challenging, especially in single-suture cases. When sutures are obliterated, sound waves fail to penetrate the cortical bone, creating an evident acoustic shadow on the underlying brain. The objective of this study was to evaluate the yield of the 'brain shadowing sign' (BSS) as a novel sonographic marker for craniosynostosis. SUBJECTS AND METHODS: Patients with an antenatal diagnosis of fetal craniosynostosis (cases) and healthy controls paired for gestational age were enrolled in this retrospective case-control study. Two-dimensional scans were assessed by three examiners for the presence of the BSS and additional fetal findings. RESULTS: The BSS was clearly depicted in all 24 cases on the first analysis and in 22 cases on the second analysis. No fetus from the control group (n = 48) presented the BSS in any of the analyses. Fifteen cases had isolated craniosynostosis and 9 were syndromic (Apert, Saethre-Chotzen and craniofrontonasal syndromes), which were diagnosed significantly earlier due to additional malformations. DISCUSSION: The BSS is a novel sonographic marker of craniosynostosis which can be used to increase the diagnostic rate of this rare condition and does not require the use of high-definition three-dimensional transducers to be depicted.

Prenatal diagnosis of a fetus with ring chromosomal 15 by two- and three-dimensional ultrasonography.

We report on a prenatal diagnosis of ring chromosome 15 in a fetus with left congenital diaphragmatic hernia (CDH) and severe intrauterine growth restriction (IUGR). A 31-year-old woman, gravida 2 para 1, was referred because of increased nuchal translucency at gestational age of 13 weeks. Comprehensive fetal ultrasound examination was performed at 19 weeks revealing an early onset IUGR, left CDH with liver herniation, and hypoplastic nasal bone. Three-dimensional ultrasound (rendering mode) showed low set ears and depressed nasal bridge. Amniocentesis was performed with a result of a 46,XX,r(15) fetus after a cytogenetic study. A 1,430 g infant (less than third percentile) was born at 36 weeks. The infant presented with respiratory failure and died at 2 h of life. Postnatal karyotype from the umbilical cord confirmed the diagnosis of 15-ring chromosome. We described the main prenatal 2D- and 3D-ultrasound findings associated with ring chromosome 15. The interest in reporting the present case is that CDH can be associated with the diagnosis of 15-ring chromosome because the critical location of the normal diaphragm development is at chromosome 15q26.1-q26.2.

Prenatal diagnosis of a large epignathus teratoma using two-dimensional and three-dimensional ultrasound: correlation with pathological findings.

Epignathus teratomas are rare tumors that originate in the region of the palate or pharynx and are known as Rathke pouch. They may be associated with other malformations such as a cleft palate and bifid tongue or nose. The prenatal diagnosis can be established by two-dimensional ultrasonography showing a heterogeneous mass protruding through the mouth of the fetus. The three-dimensional ultrasonography in rendering mode permits better understanding of this anomaly by the parents, facilitating the counseling. The importance of prenatal diagnosis lies in the fact that this tumor may obstruct the airways, thus leading to death at birth due to respiratory insufficiency. We report a case of prenatal diagnosis of epignathus teratoma in the 30th week of pregnancy by two-dimensional ultrasonography. We focus on the importance of three-dimensional ultrasonography in rendering mode for demonstrating the spatial relationships of the tumor with the oral cavity and provide correlations between the ultrasound images and the anatomopathological findings.

Prenatal diagnosis of treacher-collins syndrome using three-dimensional ultrasonography and differential diagnosis with other acrofacial dysostosis syndromes.

Treacher-Collins syndrome (TCS) is a rare dominant autosomal anomaly resulting from malformation or disruption of the development of the first and second branchial arches. It is characterized by micrognathia, malar hypoplasia, and malformations of the eyes and ears. The prenatal diagnosis using two-dimensional ultrasonography (2DUS) is characterized by identification of facial malformations together with polyhydramnios. Three-dimensional ultrasonography (3DUS) has the capacity to spatially display these facial malformations, thus making it easy for the parents to understand them. We present a case of TCS diagnosed in the 33rd week using 3DUS, with postnatal confirmation using cranial computed tomography and anatomopathological analysis.

[Analysis of the combined first trimester screening for chromosomal abnormalities]. / Análise do rastreamento combinado no primero trimestre da gestação para detecção de anomalias cromossômicas.

PURPOSE: to evaluate the performance of the combined first trimester screening for chromosomal abnormalities in a group of the Brazilian population. METHODS: a retrospective study including pregnant women with single fetuses referred to a fetal medicine center to perform the first trimester screening that combines maternal age, nuchal translucency measurement and two maternal serum biochemical markers: free B-hCG and PAPP-A. To evaluate the performance of the test, the detection rate, specificity, negative and positive predicted values and false-positive rates were calculated, considering as high risk the cut-off value above 1 in 300. RESULTS: we studied 456 patients submitted to the test. Advanced maternal age above 35 years was observed in 36.2% of cases. The incidence of chromosomal abnormalities in the study population was 2.2%. Twenty-one patients (4.6%) presented a high risk (above 1:300) by the combined test. Using this cut-off level, the detection rate of the test was 70% for all chromosomal abnormalities and 83.3% for trisomy 21, for a false-positive rate of 3.1%. CONCLUSIONS: the combined first trimester screening was effective to detect chromosomal abnormalities, mainly for trisomy 21, with low false-positive rates. The combined test contributed to decreasing the indication of an invasive test if we compare to maternal age alone as a risk factor.

Análise do rastreamento combinado no primero trimestre da gestação para detecção de anomalias cromossômicas / Analysis of the combined first trimester screening for chromosomal abnormalities

OBJETIVO: avaliar o desempenho do rastreamento combinado do primeiro trimestre da gestação na detecção de anomalias cromossômicas em um grupo da população brasileira. MÉTODO: estudo retrospectivo envolvendo gestantes com feto único, referidas ao setor de medicina fetal para a realização do teste de rastreamento do primeiro trimestre da gestação pela combinação da idade materna, a medida da translucência nucal e dois marcadores bioquímicos do soro materno: free B-hCG e PAPP-A. Para avaliar o desempenho do teste foram calculados a sensibilidade, especificidade, valores preditivos positivos e negativos e as taxas de falso positivo, considerando como risco elevado valores superiores a 1:300. RESULTADOS: foram incluídas 456 gestantes submetidas ao teste. A idade materna avançada, acima de 35 anos, ocorreu em 36,2 por cento dos casos. A incidência de cromossomopatia na população estudada foi de 2,2 por cento. Vinte e uma das gestantes (4,6 por cento) apresentou risco elevado ao teste (superior a 1:300). Usando-se este ponto de corte, a sensibilidade do teste foi de 70 por cento para as cromossomopatias em geral e 83,3 por cento para os casos de trissomia do cromossomo 21, com taxa de falso positivo de 3,1 por cento. CONCLUSÃO: o rastreamento combinado do primeiro trimestre foi eficaz na detecção das anomalias cromossômicas, principalmente em relação aos casos de trissomia 21, com baixas taxas de falso positivo. Observou-se importante contribuição do teste em reduzir a indicação do exame invasivo comparado ao uso da idade materna como fator de risco.

PURPOSE: to evaluate the performance of the combined first trimester screening for chromosomal abnormalities in a group of the Brazilian population. METHODS: a retrospective study including pregnant women with single fetuses referred to a fetal medicine center to perform the first trimester screening that combines maternal age, nuchal translucency measurement and two maternal serum biochemical markers: free B-hCG and PAPP-A. To evaluate the performance of the test, the detection rate, specificity, negative and positive predicted values and false-positive rates were calculated, considering as high risk the cut-off value above 1 in 300. RESULTS: we studied 456 patients submitted to the test. Advanced maternal age above 35 years was observed in 36.2 percent of cases. The incidence of chromosomal abnormalities in the study population was 2.2 percent. Twenty-one patients (4.6 percent) presented a high risk (above 1:300) by the combined test. Using this cut-off level, the detection rate of the test was 70 percent for all chromosomal abnormalities and 83.3 percent for trisomy 21, for a false-positive rate of 3.1 percent. CONCLUSIONS: the combined first trimester screening was effective to detect chromosomal abnormalities, mainly for trisomy 21, with low false-positive rates. The combined test contributed to decreasing the indication of an invasive test if we compare to maternal age alone as a risk factor.

Cariótipo fetal: podemos confiar sempre no seu resultado? / Fetal karyotype: can we always trust its result?

Estudo retrospectivo de seis casos em que houve discrepância entre cariótipo pré-natal e achados pós-natais. Em cinco deles as anomalias cromossômicas que foram encontradas inicialmente pela biópsia de vilosidades coriônicas ou amniocentese não foram compatíveis com resultados posteriores. Já em um caso, o cariótipo inicial normal pela biópsia de vilosidades coriônicas necessitou de novo controle devido ao aparecimento de sinais ultra-sonográficos pré-natais e sinais clínicos pós-natais. Na maioria dos casos a evolução favorável ultra-sonográfica foi o que levantou a dúvida sobre o cariótipo inicial anormal. Quando os achados ultra-sonográficos são discordantes do cariótipo encontrado inicialmente, muita cautela é necessária na interpretação dos resultados e no aconselhamento genético desses casais. O mosaicismo confinado à placenta é uma das principais causas de resultados discordantes. Desta forma, a interpretação do cariótipo fetal depende da correlação com os achados clínicos/ultra-sonográficos pré-natais.

Laser for the treatment of twin to twin transfusion syndrome

OBJETIVO: Nosso objetivo é relatar a experiência inicial no país com uma nova técnica de tratamento para a síndrome de transfusão feto-fetal (STT), onde se utiliza o raio laser para coagulação dos vasos placentários responsáveis pela transfusão entre gêmeos durante a gravidez. MÉTODOS: Estudo prospectivo de 8 casos com diagnóstico de STT avaliados pelo nosso serviço de janeiro de 2001 a junho de 2005. Introduzindo-se um fetoscópio de 2,0 mm de diâmetro na cavidade uterina, por via percutânea, foram diretamente visualizados os vasos da superfície placentária. Aqueles vasos identificados como responsáveis pela transfusão foram coagulados através do laser. O procedimento combina a ultra-sonografia e a fetoscopia, no que se denomina uma abordagem sono-endoscópica (FETENDO). RESULTADOS: Dentre as oito gestações avaliadas, o procedimento foi realizado em cinco casos (10 fetos). Todos os fetos sobreviveram por um período mínimo de cinco semanas após a cirurgia. Na evolução, oito fetos nasceram vivos e cinco sobreviveram ao período neonatal. No seguimento pós-natal de 18 meses, todos os cinco estão vivos e bem, tendo atualmente uma idade média de 10,6 meses. A sobrevida geral foi de 50%, sendo que em três gestações, pelo menos um feto sobreviveu. CONCLUSÕES: A fetoscopia com laser é atualmente considerada "gold-standard" no tratamento da STT. No entanto, a técnica é sofisticada e depende de treinamento adequado. Nosso serviço é o primeiro do país a oferecer esta técnica cirúrgica e nossos índices de sucesso se comparam aos índices mundiais.

Laser for the treatment of twin to twin transfusion syndrome.

PURPOSE: To report the initial experience in our country with a new technique for twin to twin transfusion syndrome (TTTS) treatment, using laser to coagulate the placental vessels responsible for the twin transfusion during gestation. METHODS: Prospective study of eight cases diagnosed with TTTS evaluated in our service from january 2001 to june 2005. Through percutaneous introduction of a 2,0mm diameter fetoscope in the uterine cavity, placental surface vessels where directly visualized. Those identified as responsible for the transfusion were laser coagulated. The procedure combines ultrasonography and fetoscopy, in a so-called sonoendoscopic technique (FETENDO). RESULTS: Among the eight pregnancies evaluated, five cases were submitted to the procedure (10 fetuses). All fetuses survived for at least five weeks after surgery. A total of eight fetuses were born alive and five survived the neonatal period. In a 18 months follow-up after birth, all five are still alive and well and their mean age is now 10,6 months. The total survival rate was 50% and in three pregnancies, at least one fetus survived. CONCLUSIONS: Laser fetoscopy is actually the "gold-standard" treatment of TTTS. Nevertheless is a sophisticated technique that depends of proper training. Our service is the first in our country to offer this therapeutic technique. Our success rate is comparable with the international literature.