Anatomic correlates of ultrasonographic prenatal diagnosis

In utero sonographic diagnoses from forty-five malformed infants were correlated with their autopsy findings. Fifty-two malformations were diagnosed prenatally in 42 of the patients but 90 additional malformations were not. Nine sonographically diagnosed abnormalities were not confirmed at autopsy. Factors compromising sonographic diagnosis included: limited examinations, small fetal size, timing of examination, oligohydramnios, fetal position, nature of the malformation and unfamiliarity of the ultrasonographer with specific malformation syndromes. In utero ultrasonography is an invaluable tool of diagnosing congenital malformations but has limitations.     

The role of prenatal diagnosis in the perinatal management of urinary tract abnormalities

The use of ultrasonography is one of the most appropriate and less invasive techniques for the identification of prenatal assessment of urinary tract anomalies. This technique is able to distinguish malformations which are not compatible with life from those which could benefit from appropriate prenatal management treatment in view of a successful outcome after birth. During the past three years, 13 cases of urinary tract anomalies were found and treated. On the basis of our experience, we believe that ultrasonography is especially indicated: to make an early diagnosis of the type of malformation; in the presence of a complex malformation, gives the physician the possibility of showing and explaining to the parents all the aspects involved in reconstructive surgery thus giving them the possibility to decide for abortion or not; to reveal latent malformations: in these cases postnatal treatment may be efficiently programmed. to prepare the mother for early cesarean section, thus avoiding the trauma of vaginal delivery in cases of high risk such as fetuses with hydronephrotic kidneys. Thus, together with more experience in the field of intrauterine microsurgery, the outlook on the future of fetuses with malformations is certainly becoming brighter.     

Ultrasound prenatal diagnosis of structural abnormalities

Routine screening for congenital abnormalities has become established practice, at least in the developed countries and ultrasound is the major modality used for this. Although 50–60% of all structural abnormalities can be detected as early as 11–14 weeks, the optimum timing for a full structural survey appears to be around 20 weeks. The timing is also governed by termination laws in various countries. One of the problems with screening scans was the variable way in which they were conducted throughout the UK. A minimum standard has been suggested for an anomaly scan in order to bring about uniformity in the screening program. The search for abnormalities can be initiated by a finding of Increased nuchal translucency or abnormal serum biochemistry performed as a part of Down syndrome screening program. Alternatively, a ‘routine’ anomaly scan is offered to all pregnant women. A thorough understanding of the normal ultrasound appearance of fetal structures is essential in order to detect abnormalities. When an abnormality is detected prenatally, the pregnancy usually needs a multidisciplinary team care In order to optimise the outcome.     

Ultrasound prenatal diagnosis of structural abnormalities

One of the major roles of ultrasound in pregnancy is the detection of structural abnormalities. Ultrasound screening has become an accepted part of antenatal practice. However there is a wide variety in the practice between different centers. The majority of fetal anomalies are diagnosed by ultrasound in the second trimester. However, a number of abnormalities are amenable to diagnosis as early as 11–14 weeks gestation. National guidelines have been adopted in an attempt to standardize the practice in the UK. Prenatal detection rate is higher in countries with a national screening program. Prenatal ultrasound is a screening test and will have false negatives and positives.Structural abnormalities can occur as isolated events, as part of a genetic syndrome or as a result of a chromosomal abnormality. When an abnormality is detected prenatally, a multidisciplinary approach is necessary to optimize the outcome. It is important to provide appropriate information to the prospective parents but remain non-judgmental with their decision.     

Chromosomal prenatal diagnosis: study of 936 cases of intrauterine abnormalities after ultrasound assessment

Nine hundred and thirty-six prenatal chromosomal analyses were performed by four cytogenetic centres after ultrasound diagnosis of fetal abnormalities, amniotic fluid disorders, fetal growth retardation, and fetal or placental abnormalities. During the same period, 6515 fetal karyotypes were analysed because of maternal age. Frequencies of chromosomal aberrations in each case were respectively 4.4, 6.7 and 15.8 per cent, compared with 3.18 per cent when the fetal karyotype was performed because of maternal age. High rates of chromosomal aberrations are observed in cases of cervical hygroma, limb abnormalities, omphaloceles, duodenal stenosis, hydrocephalus, and facial abnormalities. In the case of polymalformations, this rate was 29.2 per cent. When malformations were seen together with an amniotic fluid disorder or growth retardation, 21.5 per cent chromosomal aberrations were observed. This frequency was 10.4 per cent when growth retardation was associated with an amniotic fluid disorder. Trisomy 13, 18, 21 and monosomy X accounted for 4/5 of all abnormalities in which we observed a high rate of triploidies (4.9 per cent) and balanced (3.3 per cent) or unbalanced (9.8 per cent) non-Robertsonian structural abnormalities. Sonographic ascertainment of these aberrations and prenatal characteristics of major anomalies are discussed.     

Three-dimensional ultrasound in prenatal diagnosis

PURPOSE OF REVIEW: Several technological advances have greatly improved three-dimensional sonography, which have improved acquisition and display capabilities. This review describes these technical changes as well as current applications of 3D sonography in prenatal diagnosis. RECENT FINDINGS: Recently published papers have emphasized the potential of getting a precise 'any plane of choice' from a three-dimensional volume, as a new way of scanning, based on the off-line analysis of a volume dataset. Surface mode has been used to demonstrate malformations and genetic diseases. The maximum rendering mode, which highlights bones, has great potential for imaging the nasal bones and the frontal bones with the metopic suture. Organ volume can be measured, but the utility of this in clinical practice remains to be determined. Three-dimensional ultrasound needs to be standardized. SUMMARY: Three-dimensional ultrasonography is the most rapidly developing technique in fetal imaging. New features will permit the transition from the era of 'sonography in two-dimensional planes' to 'volume ultrasound'.     

Mild pyelectasis diagnosed by prenatal ultrasound is not a predictor of urinary tract morbidity in childhood

OBJECTIVES: To determine whether children with prenatally diagnosed mild pyelectasis have more urinary tract morbidity during childhood than children without this finding. METHODS: Case-control study in children with pyelectasis (anteroposterior diameter of the fetal renal pelvis of 5-10 mm). A validated questionnaire was sent to the parents of 208 cases and 416 matched controls. RESULTS: The questionnaire was returned by 146 cases and 250 controls. There was a male predominance in the case group (p = < 0.0001). There was no difference in voiding habits or in prevalence of urinary tract infections (UTI). The prevalence of UTI was high: 11.6% in cases and 10.0% in controls. The only difference was a higher prevalence of constipation in the case group (p = 0.003). Postnatally, 41 children had an ultrasound examination and 16 were referred to a paediatrician or urologist: 3 had persisting pyelectasis, 3 had a recurrent UTI and 1 required surgery (a pyeloplasty). Four of the controls were referred to a paediatrician or urologist: 3 had recurrent UTI and 1 had urinary incontinence. CONCLUSION: Children with a mild fetal pyelectasis do not have more urinary tract morbidity during childhood than children without this finding. Therefore, there seems to be no need for additional investigation after birth.     

3-D ultrasound in prenatal diagnosis

2-D ultrasonography has evolved into an excellent technique in prenatal diagnosis during the past 40 years. The fact remains, however, that 2-D ultrasonography is marked by a lack of ability to provide more than a 2-D demonstration of a 3-D fetus. Although many fetal anomalies are detectable by conventional 2-D ultrasound, it is impossible to demonstrate a defect in the third dimension. 3-D sonography not only offers the third plane, but it also provides the examiner with different viewing modes: the multiplanar, the surface and the transparent demonstration of the fetus. The different viewing modes not only improve the accuracy in detecting fetal malformations, but also serve to demonstrate the normal anatomy of the unborn more conclusively to the parents.     

Early prenatal ultrasound diagnosis of congenital thoracic malformations

Objectives: To evaluate and describe the spectrum and rate of congenital thoracic malformations (CTMs) diagnosed by early prenatal sonography (gestational age (GA) less than 16 weeks).

Methods: A retrospective, cross-sectional analysis of prenatal ultrasound screening tests in a community-based clinic.

Results: In 2001–2017, 31 261 prenatal ultrasound tests detected 31 CTMs at a gestational age of 15.2 (range, 11.6–16.0) weeks. The most common malformation was congenital pleural effusion (CPE) (15 fetuses, 0.48/1000), followed by congenital diaphragmatic hernia (CDH) (10 fetuses, 0.32/1000). Pulmonary hypoplasia (PH), congenital pulmonary airway malformation and broncho-pulmonary sequestration appeared in much smaller proportions (three, two and one fetuses, respectively). Most CTMs were associated with additional fetal lesions (15 fetuses, 48%). All early CDH (10 fetuses) and PH (three fetuses) and 6/15 with CPE had termination of pregnancy or missed abortions.

Conclusions: Prenatal ultrasound before 16 GA was able to detect CTMs in 0.99/1000 of screening ultrasound (US) performed. Most CTMs tended to appear with multiple lesions and were associated with unfavorable outcomes. Earlier prenatal diagnosis may enable early termination of pregnancy in fetuses with lethal malformations.     

Doppler ultrasound in prenatal prediction and diagnosis.

Preeclampsia, intrauterine growth retardation, and abruptio placentae are associated with the failure of the placenta to create an adequate communication with the maternal vasculature and subsequently reduced placental perfusion, with secondary effects on villous maturation and placental function, thereby failing to meet the needs of the growing fetus. Also, primary failure of placental maturation has been linked with the chromosomally abnormal fetus. Doppler ultrasound allows examination of blood flow in maternal and fetal vessels and assists in our ability to understand, predict, and diagnose pregnancy complications. Over the last 10 years there has been a rapid development in the capacity and complexity of the equipment used for clinical Doppler examination, from simple continuous wave devices to duplex-color flow systems, and the advantages of these developments continue to be defined. As with all innovations there has been a period of extensive appraisal of this technology, and further applications of Doppler await clarification. This review puts the most recent publications in perspective, and points to the likely areas of interest in the future.     

Parental decisions following the prenatal diagnosis of sex chromosome abnormalities

OBJECTIVE: To report parental decisions regarding pregnancy termination following the prenatal diagnosis of a sex chromosome abnormality (SCA) in the fetus. METHODS: Retrospective collection of data from records of 61 families receiving genetic counseling after prenatal diagnosis of a sex chromosome abnormality in the fetus in the Division of Medical Genetics, University Hospital of Geneva during the time period 1980-2001. RESULTS: Among 61 couples with a prenatal diagnosis of a sex chromosome abnormality (SCA), 44 couples (72.1%) decided to terminate pregnancy. Pregnancy termination rates were 100, 73.9, 70, 50 and 42.9% for Turner syndrome, Klinefelter syndrome, 47,XXX females, 47,XYY males, and mosaic cases, respectively. In all 11 cases with a fetal abnormality seen on ultrasound, pregnancy was terminated. Termination rates were higher among couples with a higher mean number of previous children. Maternal age and year of test did not influence parental decisions. CONCLUSIONS: Parental decision to terminate a pregnancy for a fetus with a SCA varied by type of sex chromosome abnormality, by presence of fetal ultrasound anomalies, and by the mean number of previous children.