A unified protocol is essential to ensure that fetal ultrasound measurements taken in multicentre research studies are accurate and reproducible. This paper describes the methodology used to take ...two‐dimensional, ultrasound measurements in the longitudinal, fetal growth component of the INTERGROWTH‐21st Project. These standardised methods should minimise the systematic errors associated with pooling data from different study sites. They represent a model for carrying out similar research studies in the future.
During the past century, imaging of the pregnant patient has been performed with radiography, scintigraphy, computed tomography, magnetic resonance imaging, and ultrasonography (US). US imaging has ...emerged as the primary imaging modality, because it provides real-time images at relatively low cost without the use of ionizing radiation. This review begins with a discussion of the history and current status of imaging modalities other than US for the pregnant patient. The discussion then turns to an in-depth description of how US technology advanced to become such a valuable diagnostic tool in the obstetric patient. Finally, the broad range of diagnostic uses of US in these patients is presented, including its uses for distinguishing an intrauterine pregnancy from a failed or ectopic pregnancy in the first trimester; assigning gestational age and assessing fetal weight; evaluating the fetus for anomalies and aneuploidy; examining the uterus, cervix, placenta, and amniotic fluid; and guiding obstetric interventional procedures.
Pautas de ISUOG para la práctica: evaluación ecográfica de la biometría y el crecimiento fetal
INTRODUCCIÓN
El objetivo de estas Pautas es describir la evaluación adecuada de la biometría fetal y el ...diagnóstico de los trastornos del crecimiento fetal. Estos trastornos consisten principalmente en la restricción del crecimiento fetal (RCF), también conocida como restricción del crecimiento intrauterino (RCIU), que a menudo está asociada con un tamaño pequeño para la edad gestacional (PEG) o grande para la edad gestacional (GEG), que pueden dar lugar a la macrosomía fetal; ambos se han asociado con una variedad de resultados maternos y perinatales adversos. La detección y el tratamiento adecuado de las anomalías del crecimiento fetal son componentes esenciales de la atención prenatal, y la ecografía fetal desempeña un papel fundamental en la evaluación de estas afecciones. Los parámetros biométricos fetales medidos con mayor frecuencia son (todas las siglas procedentes del inglés) el diámetro biparietal (BPD), el perímetro cefálico (HC), el perímetro abdominal (AC) y la longitud de la diáfisis del fémur (FL). Estas mediciones biométricas se pueden utilizar para estimar el peso del feto (PEF) mediante fórmulas diferentes1. Es importante diferenciar entre el concepto de tamaño fetal en un momento dado y el crecimiento fetal en sí, siendo este último un proceso dinámico cuya evaluación requiere al menos dos ecografías separadas en el tiempo. La historia y los síntomas de la madre, la evaluación del líquido amniótico y la velocimetría Doppler pueden proporcionar información adicional que se puede utilizar para identificar los fetos bajo riesgo de resultados adversos del embarazo. La estimación precisa de la edad gestacional es un prerrequisito para determinar si el tamaño del feto es apropiado para la edad gestacional (AEG). Excepto en el caso de los embarazos procedentes de tecnologías de reproducción asistida, la fecha de concepción no se puede determinar con precisión. Clínicamente, la fecha de la mayoría de los embarazos se establece en función del último período menstrual, aunque a veces esto puede ser incierto o poco fiable. Por lo tanto, el fechado de los embarazos mediante ecografía temprana a las 8‐14 semanas, mediante la medición de la longitud céfalo‐caudal (LCC) fetal, parece ser el método más fiable para establecer la edad gestacional. Una vez que la LCC excede los 84 mm, se debe usar el HC2–4 para establecer la fecha del embarazo. El HC, con o sin FL, se puede utilizar para estimar la edad gestacional a partir de la mitad del primer trimestre si no se dispone de una ecografía del primer trimestre y el historial menstrual no es fiable. Cuando se ha establecido la fecha prevista del parto mediante una exploración temprana precisa, no se deben utilizar exploraciones posteriores para recalcular la edad gestacional1. Las exploraciones en serie se pueden utilizar para determinar si el intervalo del crecimiento ha sido normal. En estas Pautas se asume que la edad gestacional es conocida y ha sido determinada según lo anterior, que el embarazo es de feto único y que la anatomía fetal es normal. En el Apéndice 1 se detallan los grados de recomendación utilizados en estas Pautas. El informe sobre los niveles de evidencia no es aplicable a estas Pautas.
摘要
ISUOG实践指南:胎儿生物测量与生长的超声评估
引言
本指南旨在描述胎儿生物测量的正确评估及胎儿生长障碍的诊断。这些疾病主要包括又称为宫内生长受限(IUGR)且往往与小于胎龄(SGA)有关的胎儿生长受限(FGR)，以及可能导致胎儿巨大的大于胎龄(LGA)。这两种疾病都与各种孕产期围产期不良结局有关。胎儿生长异常的筛查和适当处理是产前保健的重要组成部分，胎儿超声检测在这些疾病的评估中起着关键作用。最常测量的胎儿生物特征参数有双顶径(BPD)、头围(HC)、腹围(AC)和股骨骨干长度(FL)。可以根据这些生物特征测量值，运用各种不同的公式估算胎儿体重(EFW)。1务必要区分给定时间点胎儿大小与胎儿生长这两个不同的概念，后者是一个动态的过程。胎儿生长评估至少需要不同时间点的两次超声波扫描检测。产妇的病史和症状、羊水评估和多普勒测速可以提供更多信息，可以据此识别有不良妊娠结局风险的胎儿。准确估算胎龄是确定胎儿大小是否适合胎龄(AGA)的先决条件。无法精确确定受孕日期，辅助生殖技术引发的妊娠除外。临床上主要将末次月经日期定为受孕日期，虽然有时可能不太确定或不太可靠。因此，根据胎冠臀长(CRL)测量结果和第8‐14周早期超声波检测结果确定受孕日期，似乎是确定胎龄的最可靠方法。如果CRL超过84毫米，就要根据HC来确定受孕日期。2–4如果无法进行孕早期扫描且月经史不可靠，就可以通过HC——不管有没有FL——来估算孕中期孕龄。通过准确的孕早期扫描确定预产期后，就不要再做后续扫描来重新估算胎龄了。1可以通过连续扫描确定胎儿间隔生长是否正常。在本指南中，我们假设胎龄已知且已通过上述方式确定胎龄，孕产单生儿且胎儿解剖正常。本指南所用的推荐等级详情如附录1所示。本指南不适用报告证据等级。
This article's has been translated into Spanish and Chinese. Follow the links from the to view the translations.
To report on the ultrasound quality assurance program for the National Institute of Child Health and Human Development Fetal Growth Studies and describe both its advantages and generalizability.
...After training on an ultrasound system and software, research sonographers were expected to capture blank (unmeasured) images in triplicate for crown-rump length, biparietal diameter, head circumference, abdominal circumference, and femur length. A primary expert sonographer was designated and validated. A 5% sample (n = 740 of 14,785 scans) was randomly selected in 3 distinct rounds from within strata of maternal body mass index (round 1 only), gestational age, and research site. Unmeasured images were extracted from selected scans and measured with the ultrasound software by an expert sonographer. Correlations and coefficients of variation (CVs) were calculated, and the within-measurement standard deviation (ie, technical error of the measurement), was calculated.
The reliability between the site sonographers and the expert was high, with correlations exceeding 0.99 for all dimensions in all rounds. The CV % values showed low variability, with the percentage differences being less than 2%, except for abdominal circumference in rounds 2 and 3, in which it averaged about 3%. Correlations remained high (>0.90) with increasing fetal size; there was a monotonic increase in technical errors of the measurement but without a corresponding increase in the CV %.
Using rigorous procedures for training sonographers, coupled with quality assurance oversight, we determined that the measurements acquired longitudinally for singletons are both accurate and reliable for establishment of an ultrasound standard for fetal growth.
Background
One of the main aims of routine antenatal care is to identify the 'at risk' fetus in order to apply clinical interventions which could result in reduced perinatal morbidity and mortality. ...Doppler ultrasound study of umbilical artery waveforms helps to identify the compromised fetus in 'high‐risk' pregnancies and, therefore, deserves assessment as a screening test in 'low‐risk' pregnancies.
Objectives
To assess the effects on obstetric practice and pregnancy outcome of routine fetal and umbilical Doppler ultrasound in unselected and low‐risk pregnancies.
Search methods
We searched the Cochrane Pregnancy and Childbirth Group Trials Register (28 February 2015) and reference lists of retrieved studies.
Selection criteria
Randomised and quasi‐randomised controlled trials of Doppler ultrasound for the investigation of umbilical and fetal vessels waveforms in unselected pregnancies compared with no Doppler ultrasound. Studies where uterine vessels have been assessed together with fetal and umbilical vessels have been included.
Data collection and analysis
Two review authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction. In addition to standard meta‐analysis, the two primary outcomes and five of the secondary outcomes were assessed using GRADE software and methodology.
Main results
We included five trials that recruited 14,624 women, with data analysed for 14,185 women. All trials had adequate allocation concealment, but none had adequate blinding of participants, staff or outcome assessors. Overall and apart from lack of blinding, the risk of bias for the included trials was considered to be low.
Overall, routine fetal and umbilical Doppler ultrasound examination in low‐risk or unselected populations did not result in increased antenatal, obstetric and neonatal interventions. There were no group differences noted for the review's primary outcomes of perinatal death and neonatal morbidity. Results for perinatal death were as follows: (average risk ratio (RR) 0.80, 95% confidence interval (CI) 0.35 to 1.83; four studies, 11,183 participants). Only one included trial assessed serious neonatal morbidity and found no evidence of group differences (RR 0.99, 95% CI 0.06 to 15.75; one study, 2016 participants).
For the comparison of a single Doppler assessment versus no Doppler, evidence for group differences in perinatal death was detected (RR 0.36, 95% CI 0.13 to 0.99; one study, 3891 participants). However, these results are based on a single trial, and we would recommend caution when interpreting this finding.
There was no evidence of group differences for the outcomes of caesarean section, neonatal intensive care admissions or preterm birth less than 37 weeks.
When the quality of the evidence for the main comparison of 'All Doppler versus no Doppler' was assessed with GRADE software, the outcomes of perinatal death and serious neonatal morbidity data were graded as of low quality. Evidence for the outcome of stillbirth was graded according to regimen subgroups ‐ with a moderate quality rating for stillbirth (fetal/umbilical vessels only) and a low quality rating for stillbirth (fetal/umbilical vessels + uterine artery vessels). Evidence for admission to neonatal intensive care unit was assessed as of moderate quality, and evidence for the outcomes of caesarean section and preterm birth less than 37 weeks was graded as of high quality.
There is no available evidence to assess the effect on substantive long‐term outcomes such as childhood neurodevelopment and no data to assess maternal outcomes, particularly maternal satisfaction.
Authors' conclusions
Existing evidence does not provide conclusive evidence that the use of routine umbilical artery Doppler ultrasound, or combination of umbilical and uterine artery Doppler ultrasound in low‐risk or unselected populations benefits either mother or baby. Future studies should be designed to address small changes in perinatal outcome, and should focus on potentially preventable deaths.
We investigated how accurately low-cost ultrasound devices can estimate gestational age (GA) using both the standard plane and the obstetric sweep protocol (OSP). The OSP can be taught to health care ...workers without prior knowledge of ultrasound within one day and thus avoid the need to train dedicated sonographers. Three low-cost ultrasound devices were compared with one high-end ultrasound device. GA was estimated with the head circumference (HC), abdominal circumference (AC) and femur length (FL) using both the standard plane and the OSP. The results revealed that the HC, AC and FL can be used to estimate GA using low-cost ultrasound devices in the standard plane within the inter-observer variability presented in the literature. The OSP can be used to estimate GA by measuring the HC and the AC, but not the FL. This study shows that it is feasible to estimate GA in resource-limited countries with low-cost ultrasound devices using the OSP. This makes it possible to estimate GA and assess fetal growth for pregnant women in rural areas of resource-limited countries.
Abstract Objective To assist clinicians in assigning gestational age based on ultrasound biometry. Outcomes To determine whether ultrasound dating provides more accurate gestational age assessment ...than menstrual dating with or without the use of ultrasound. To provide maternity health care providers and researchers with evidence-based guidelines for the assignment of gestational age. To determine which ultrasound biometric parameters are superior when gestational age is uncertain. To determine whether ultrasound gestational age assessment is cost effective. Evidence Published literature was retrieved through searches of PubMed or MEDLINE and The Cochrane Library in 2013 using appropriate controlled vocabulary and key words (gestational age, ultrasound biometry, ultrasound dating). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies written in English. There were no date restrictions. Searches were updated on a regular basis and incorporated in the guideline to July 31, 2013. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. Values The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). Benefits, harms, and costs Accurate assignment of gestational age may reduce post-dates labour induction and may improve obstetric care through allowing the optimal timing of necessary interventions and the avoidance of unnecessary ones. More accurate dating allows for optimal performance of prenatal screening tests for aneuploidy. A national algorithm for the assignment of gestational age may reduce practice variations across Canada for clinicians and researchers. Potential harms include the possible reassignment of dates when significant fetal pathology (such as fetal growth restriction or macrosomia) result in a discrepancy between ultrasound biometric and clinical gestational age. Such reassignment may lead to the omission of appropriate—or the performance of inappropriate—fetal interventions.
Quantitative imaging of the cervix: setting the bar Feltovich, H.; Hall, T. J.
Ultrasound in obstetrics & gynecology,
February 2013, 2013-Feb, 2013-02-00, 20130201, Letnik:
41, Številka:
2
Journal Article
Zika Virus Infection — After the Pandemic Musso, Didier; Ko, Albert I; Baud, David
The New England journal of medicine,
10/2019, Letnik:
381, Številka:
15
Journal Article
Recenzirano
Odprti dostop
Zika is a mosquito-borne flavivirus that can cause congenital defects, including microcephaly. Although most Zika virus infections are asymptomatic, rash, fever, arthralgia, myalgia, and ...conjunctivitis can develop in some people. The Guillain–Barré syndrome occurs in 2 to 3 patients per 10,000 with Zika virus infection.
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