Self-made transvaginal ultrasound simulator: new training equipment in ultrasound evaluation of controlled ovarian stimulation and oocyte retrieval.

Aim: We sought to create and describe a self-made simulator designed and created for teaching purposes: a high-fidelity ultrasound phantom for demonstrating antral follicle count, ultrasound supervision of controlled of ovarian stimulation, and ultrasound-guided oocyte retrieval. Materials and methods: The uterus and ovaries of the ultrasound phantom were made from beef tongue, a male condom, latex gloves, cotton suture threads, bi-distilled water, and ultrasound gel. The components were placed in a pelvis created using three-dimensional (3D) printing. The phantom was presented to and evaluated by a group of 14 physicians pursuing a postgraduate course in reproductive medicine. Two training stations were structured: one to simulate antral follicle count and controlled ovarian stimulation and the other to simulate ultrasound-guided oocyte retrieval. Future specialists were requested to complete a feedback questionnaire evaluating the self-made simulator and the two practice stations. Results: The transvaginal ultrasound phantom was successfully created, making it possible to simulate antral follicle count, ultrasound control of ovarian hyperstimulation, and oocyte retrieval, and to capture ultrasound images. A review of the answers provided in the feedback questionnaire showed that the phantom had a good appearance and design, was realistic, helped to improve motor coordination, and could be a useful tool in the training of specialists in assisted reproduction. Conclusion: This phantom was designed to enable instruction and practice in the evaluation of ovarian follicles and ultrasound-guided oocyte retrieval in a supervised training environment. This self-made simulator is proposed as a training tool that could be included in the curricular structure of residency and postgraduate programs in reproductive medicine.

Assessment of length of maternal cervix between 18 and 24 weeks of gestation in a low-risk brazilian population / Avaliação do comprimento do colo uterino materno entre 18 e 24 semanas de gestação em uma população brasileira de baixo risco

Abstract Purpose To determine cervical biometry in pregnant women between 18 and 24 weeks of gestation and the ideal mode of measurement of cervical length in cases of curved and straight cervical morphology. Methods The uterine cervices of 752 low-risk pregnant women were assessed using transvaginal ultrasound in a prospective cross-sectional study. In women with straight uterine cervices, cervical biometry was performed in a continuous manner. In women with curved uterine cervices, the biometry was performed using both the continuous and segmented techniques (in segments joining the cervical os). Polynomial regression models were created to assess the correlation between the cervical length and gestational age. The paired Student t-test was used to comparemeasuring techniques. Results The cervical biometry results did not vary significantly with the gestational age and were best represented by linear regression (R2 = 0.0075 with the continuous technique, and R2 = 0.0017 with the segmented technique). Up to the 21st week of gestation, there was a predominance of curved uterine cervix morphology (58.9%), whereas the straight morphology predominated after this gestational age (54.2%). There was a significant difference between the continuous and the segmented measuring methods in all the assessed gestational ages (p < 0.001). Conclusion Cervical biometry in pregnant women between 18 and 24 weeks was represented by a linear regression, independently of the measuring mode. The ideal measuring technique was the transvaginal ultrasound performed at a gestational age 21 weeks.

Resumo Objetivo Determinar a biometria cervical em gestantes entre a 18ª e 24ª semanas, e ainda a forma ideal de mensuração do comprimento do colo uterino em casos de morfologias curva e reta. Métodos Foram realizadas avaliações ultrassonográficas via vaginal dos colos uterinos de 752 gestantes de baixo risco em um estudo prospectivo transversal. Nos colos uterinos retos a biometria cervical foi feita de forma contínua, enquanto nos colos uterinos curvos, a biometria foi realizada de duas formas, contínua e fracionada (em segmentos unindo os orifícios do colo). Para avaliar a correlação entre o comprimento do colo uterino e a idade gestacional, foram criados modelos de regressão polinomial. Para se comparar a técnicas de medida do colo uterino, utilizou-se o teste t-Student pareado. Resultados A biometria do colo uterino não variou de forma significativa com a idade gestacional, sendo melhor representada por uma regressão linear (R2 = 0,0075 na forma contínua, e R2 = 0,0017 na forma fracionada, respectivamente). Observamos que até a 21ª semana houve predominância de colos curvos (58,9%), porém após esta idade gestacional a morfologia retilínea predominou (54,2%). Houve diferença estatisticamente significativa entre a forma de mensuração contínua e fracionada em todas as idades gestacionais avaliadas (p < 0,001). Conclusão A expressão da biometria cervical em gestantes entre 18 e 24 semanas é praticamente uma reta, independente da forma de mensuração. A forma ideal de medida é por ultrassonografia transvaginal realizada em idade gestacional 21 semanas.

Assessment of Length of Maternal Cervix between 18 and 24 weeks of Gestation in a Low-Risk Brazilian Population.

Purpose To determine cervical biometry in pregnant women between 18 and 24 weeks of gestation and the ideal mode of measurement of cervical length in cases of curved and straight cervical morphology. Methods The uterine cervices of 752 low-risk pregnant women were assessed using transvaginal ultrasound in a prospective cross-sectional study. In women with straight uterine cervices, cervical biometry was performed in a continuous manner. In women with curved uterine cervices, the biometry was performed using both the continuous and segmented techniques (in segments joining the cervical os). Polynomial regression models were created to assess the correlation between the cervical length and gestational age. The paired Student t-test was used to compare measuring techniques. Results The cervical biometry results did not vary significantly with the gestational age and were best represented by linear regression (R2 = 0.0075 with the continuous technique, and R2 = 0.0017 with the segmented technique). Up to the 21st week of gestation, there was a predominance of curved uterine cervix morphology (58.9%), whereas the straight morphology predominated after this gestational age (54.2%). There was a significant difference between the continuous and the segmented measuring methods in all the assessed gestational ages (p < 0.001). Conclusion Cervical biometry in pregnant women between 18 and 24 weeks was represented by a linear regression, independently of the measuring mode. The ideal measuring technique was the transvaginal ultrasound performed at a gestational age ≥21 weeks.

Objetivo Determinar a biometria cervical em gestantes entre a 18ª e 24ª semanas, e ainda a forma ideal de mensuração do comprimento do colo uterino em casos de morfologias curva e reta. Métodos Foram realizadas avaliações ultrassonográficas via vaginal dos colos uterinos de 752 gestantes de baixo risco em um estudo prospectivo transversal. Nos colos uterinos retos a biometria cervical foi feita de forma contínua, enquanto nos colos uterinos curvos, a biometria foi realizada de duas formas, contínua e fracionada (em segmentos unindo os orifícios do colo). Para avaliar a correlação entre o comprimento do colo uterino e a idade gestacional, foram criados modelos de regressão polinomial. Para se comparar a técnicas de medida do colo uterino, utilizou-se o teste t-Student pareado. Resultados A biometria do colo uterino não variou de forma significativa com a idade gestacional, sendo melhor representada por uma regressão linear (R2 = 0,0075 na forma contínua, e R2 = 0,0017 na forma fracionada, respectivamente). Observamos que até a 21ª semana houve predominância de colos curvos (58,9%), porém após esta idade gestacional a morfologia retilínea predominou (54,2%). Houve diferença estatisticamente significativa entre a forma de mensuração contínua e fracionada em todas as idades gestacionais avaliadas (p < 0,001). Conclusão A expressão da biometria cervical em gestantes entre 18 e 24 semanas é praticamente uma reta, independente da forma de mensuração. A forma ideal de medida é por ultrassonografia transvaginal realizada em idade gestacional ≥21 semanas.

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.

Fetal nuchal fold thickness measurement between 18 and 24 weeks of pregnancy: reference intervals for a Brazilian population.

OBJECTIVE: To determine reference intervals of fetal nuchal fold (NF) thickness measurement in the second trimester of pregnancy in a Brazilian population. METHODS: This was a retrospective cross-sectional study with 2559 normal singleton pregnancies between 18 and 24 weeks of pregnancy. The fetal NF was obtained in the axial plane of fetal head at level of lateral ventricles including the cavum septum pellucidum, third ventricle, thalamus and transverse cerebellar diameter. The NF was measured posterior to the occipital bone, from the bone surface to the skin, including only soft tissue. To assess the correlation between fetal NF and gestational age (GA), polynomial equations were calculated and adjusted to determination coefficient (R(2)). RESULTS: The mean fetal NF ranged from 3.98 ± 1.14 mm at 18-18+6 to 4.83 ± 0.93 mm at 24-24+6 weeks of gestation. A good correlation was observed between fetal NF and GA, which is better represented by a linear equation: NF=1.055+0.158*GA (R(2) =0.06). CONCLUSION: Reference intervals of fetal NF thickness measurement in the second trimester of pregnancy were determined for a 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 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 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 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.

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.

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 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.

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.

Occult spinal dysraphism in the presence of rare cutaneous stigma in a neonate: importance of ultrasound and magnetic resonance imaging.

Occult spinal dysraphism is defined as a group of dystrophic conditions below an intact cover of dermis and epidermis. Ultrasonography using linear transducers is a fast, inexpensive, and effective method that makes it possible to view the content of the vertebral canal and bone structures. Magnetic resonance imaging (MRI) is reserved for elucidating the type of dysraphism and for planning corrective surgery. We present a case of a five-day-old female neonate who presented cutaneous stigmas (in the lumbar region, hands, and feet), in whom ultrasonography demonstrated dysraphism in the lumbar region. MRI confirmed the type of dysraphism and enabled surgical planning.

Diagnosis of Intra-Abdominal Extralobar Pulmonary Sequestration by means of Ultrasound in a Neonate.

Pulmonary sequestration is a congenital abnormality consisting of a mass of pulmonary tissue that presents an abnormal connection with the tracheobronchial tree, with a blood supply coming from an anomalous artery derived from the systemic circulation. Extralobar pulmonary sequestration is characterized by having pleural coverings that are independent of the normal lungs, with vascular supply usually coming from the aorta or from one of its branches. This diagnosis can be suspected prenatally if an abdominal mass, generally below the diaphragm, is seen. Here, we present a case of a neonate on the second day of life, with ultrasonography showing extralobar pulmonary sequestration located above the left adrenal gland that prenatally simulated a neuroblastoma.

Short cervix syndrome: current knowledge from etiology to the control.

BACKGROUND: Preterm delivery is one of the most serious public health problems and is the most important factor relating to neonatal morbidity and mortality. The strategies for preventing it include understanding the risk factors, with specific interventions. Recently, uterine cervix measurements using ultrasonography and vaginal administration of progesterone have gained importance in predicting and secondarily preventing spontaneous preterm delivery. OBJECTIVE: To describe the short cervix syndrome, including its etiology, diagnosis, and possible therapies. METHODS: Research in ISI, Pubmed, and Scielo database using the words short cervix, preterm delivery, sludge, cervical funneling, cervical gland area, progesterone, cerclage, and pessary. RESULTS: We found a lot of articles about this topic, including randomized controlled trials. The etiology is multifactorial, being the diagnosis based in a cervix shortening at 20-24 weeks. The history and measurement of cervix length by transvaginal ultrasound have been shown to be effective to select the high risk pregnancies. The progesterone, cervical cerclage, and cervical pessary showed to be effective to reduce the preterm delivery in pregnant women with short cervix. CONCLUSION: The successful management of pregnant women presenting a short cervix depends on the understanding that cervical shortening is the final common path for several causes of preterm delivery. The best approach should be individualized to each patient.

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.

Diagnóstico pré-natal de rabdomioma cardíaco fetal pela ultrassonografia: relato de caso / Prenatal sonographic diagnosis of fetal cardiac rhabdomyoma: a case report

Os tumores cardíacos constituem condição rara, com incidência entre 0,17 e 28/10.000 na população geral. Os rabdomiomas são os tumores mais frequentes no período pré-natal. Este trabalho tem como objetivo relatar o caso de um feto com 31 semanas de gestação que apresentava tumoração intracardíaca de grandes dimensões, com graves repercussões clínicas.

Cardiac tumors constitute a rare condition, affecting 0.17-28/10,000 of the general population. Rhabdomyomas represent the most frequently found type of tumor in the prenatal period. The present report describes the case of a 31-week fetus presenting with a large intracardiac tumor with severe clinical repercussions.

Aplicação de um novo software em ultra-sonografia 3D para o diagnóstico pré-natal de malformações fetais / Application of a new software in the 3D-sonography for prenatal diagnosis of fetal malformations

O surgimento da ultra-sonografia tridimensional no início da década de 90 representou significativo avanço na área de diagnóstico por imagem em Obstetrícia. A partir do modo multiplanar, podem-se obter múltiplos planos em diversas direções, o que não é possível ao modo bidimensional. O modo de superfície permite avaliar em detalhes a superfície fetal e permite mais fácil entendimento da doença pelos pais. Entretanto, a maior limitação da ultra-sonografia tridimensional em relação à ressonância magnética é a incapacidade de determinar múltiplos planos seqüenciais, de forma a se determinar o nível exato da malformação. Nos últimos dois anos, um novo software chamado 3D XItm tem sido proposto como uma forma de se eliminar essa limitação. Este se constitui de três programas chamados multi-slice view, volume CT view e oblique view. O multi-slice view possibilita a obtenção de múltiplos planos seqüenciais adjacentes, o volume CT view permite obter o nível exato da lesão e o oblique view viabiliza a obtenção de planos não padronizados de estruturas com contornos irregulares. Neste artigo, são apresentados: a descrição técnica, as potenciais aplicabilidades em diagnóstico pré-natal, as possíveis limitações técnicas e uma revisão do que há de mais atual na literatura sobre o software 3D XItm.

The appearance of the three-dimensional ultrasonography in the beginning of the 90s represented a great advance in diagnostic imaging in obstetrics. Through the multiplanar mode it is now possible to obtain multiple plans in several directions, something impossible with two-dimensional mode. The Surface mode allows the detailed assessment of fetal surface and allows the pathology easier understanding by the parents. Yet, three-dimensional ultrasonography is limited when comparing to magnetic resonance due to the impossibility in determining sequential multiple plans, which help to establish the exact place of the investigated malformation. For the last couple of years a new software called 3D XItm has been proposed as a way to avoid that limitation. The software includes three programs called multi-slice view, volume CT view and the oblique view. Multi-slice view makes possible to obtain the exact location of the lesion, while the oblique view allows the obtainment of non-patterned plans of structures with irregular shapes. In this article we present the technical description, potential applicabilities in prenatal diagnosis, possible technical limitations and a review of what is more recent in medical literature about the 3D XItm software.

Avaliação biométrica do colo uterino durante a gestação por meio da ultra-sonografia transvaginal e ressonância magnética / Biometric analysis of uterine cervix during pregnancy using transvaginal ultrasonography and magnetic resonance imaging

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.

OBJECTIVE: To evaluate the uterine cervix length with magnetic resonance imaging in comparison with findings at transvaginal ultrasonography. MATERIALS AND METHODS: Twenty pregnant women between the 19th and 30th gestational weeks underwent magnetic resonance imaging and transvaginal ultrasonography for evaluation of their uterine cervix. Measurements by means of magnetic resonance imaging were performed by two specialists in imaging diagnosis for calculating the interobserver variability of the method. RESULTS: Calculation of the Pearson's correlation coefficient between measurements of the cervical length demonstrated a significant correlation between the results of both methods (r=0.628; p<0.01). The paired t test demonstrated no statistically significant difference between measurements obtained by transvaginal ultrasonography and magnetic resonance imaging (p=0.068). Interobserver agreement in cervical measurements by magnetic resonance imaging was high (a=0.96), demonstrating the reliability of the method. CONCLUSION: The comparison between both imaging methods in the evaluation of cervical biometry showed no statistically significant difference thus reinforcing the utilization of ultrasonography. However, in some cases where transvaginal ultrasonography is contraindicated, magnetic resonance imaging can be alternatively utilized for measurement of the cervical length.