Prenatal identification of esophageal atresia: the role of ultrasonography for evaluation of functional anatomy

The prenatal detection of distal tracheoesophageal fistulas in fetuses diagnosed with esophageal atresia

BACKGROUND

Esophageal atresia is a major anomaly of varying severity. The complexity of surgical correction depends on the presence of a distal fistula.

OBJECTIVE

This study aimed to determine the feasibility and accuracy of prenatal ultrasound detection of the distal fistula in fetuses diagnosed with esophageal atresia.

STUDY DESIGN

This was an observational study conducted at a single tertiary care center between 2019 and 2021. Included were pregnant patients carrying a fetus prenatally diagnosed with esophageal atresia that was confirmed postnatally during corrective surgery or at postmortem autopsy. During the scan, the performing investigator determined the presence or absence of a distal fistula by scanning the location of the lower esophagus during fetal breathing. Cases in which the lower esophagus was observed distending with amniotic fluid during breathing were deemed "fistula present," and the remaining cases "fistula absent." Test feasibility and performance indices, including sensitivity, specificity, and positive and negative predictive value were calculated. The offline clips and images were reviewed by 2 investigators for the assessment of interoperator agreement using Cohen's Kappa formula.

RESULTS

Included were 16 fetuses with esophageal atresia scanned between 2019 and 2021. All fetuses were successfully scanned with sufficient resolution of the area of interest during at least 3 cycles of breathing. It took a median of 8.5 minutes to determine the presence or absence of a distal fistula. The feasibility of the test was 100% (16/16). The test's sensitivity, specificity, and positive and negative predictive values were 80% (95% confidence interval, 55-100), 100% (95% confidence interval, 60-100), 100% (95% confidence interval, 65-100), and 75% (95% confidence interval, 45-100), respectively. The Cohen's Kappa for interoperator agreement was calculated to be 1, P<.001, corresponding to a "perfect" level of agreement.

CONCLUSION

Distal fistulas in esophageal atresia can be demonstrated prenatally by targeted scanning using appropriate technique. The method provided is feasible, reproducible, and has excellent performance indices. This novel technique and observations may improve the prenatal diagnosis and counseling of esophageal atresia.

Oesophageal atresia: sonographic signs may prenatally predict surgical complexity

OBJECTIVE

Oesophageal atresia (OA) is a major anomaly of varying severity. The complexity of surgical correction highly depends on the gap length of missing oesophagus and the presence of a distal fistula. The aim of this study was to identify antenatal sonographic findings associated with presence of a distal fistula and type of surgical repair METHODS: Prenatal medical records of neonates postnatally diagnosed with OA were reviewed. Sonographic signs of OA (small/absent stomach, polyhydramnios, oesophageal pouch) and the trimester at sign detection were recorded and compared between (1) OA with and without a distal fistula and (2) early one-step versus delayed two-step anastomosis. Multivariate analysis was performed.

RESULTS

Overall, 80 cases of OA were included. Absence of a distal fistula was significantly associated with higher rates of small/absent stomach (100% vs 28.6%, P<0.0001), oesophageal pouch (100% vs 24.3%, P<0.0001) and severe polyhydramnios (66.7% vs 22.9%, P=0.006), compared with OA with a distal fistula.Cases requiring a delayed two-step repair had higher rates of small/absent stomach (84.2% vs 16.7%, P>0.0001), severe polyhydramnios (47.4% vs 16.7%, P=0.008) and oesophageal pouch (73.7% vs 18.5%, P<0.0001), compared with those corrected in an early one-step anastomosis.Multivariate logistic regression found small/absent stomach and pouch to be significantly and independently associated with a delayed two-step anastomosis.

CONCLUSION

OA without a distal fistula is associated with higher rates of prenatal sonographic signs. Both small/absent stomach and a pouch are independently associated with a delayed two-step anastomosis. These findings may help improve antenatal parental counselling regarding the anticipated surgical repair.

Dynamic esophageal patency assessment: an effective method for prenatally diagnosing esophageal atresia

BACKGROUND

Esophageal atresia is a major anomaly with a low prenatal detection rate. We propose a sonographic method termed dynamic esophageal patency assessment.

OBJECTIVE

This study aimed to assess the feasibility and performance of the dynamic esophageal patency assessment in a high-risk population.

STUDY DESIGN

A prospective study was conducted in a single tertiary fetal ultrasound unit for 12 months. The study group included pregnant women referred for a targeted scan because of one or more of the following: (1) polyhydramnios; (2) small or absent stomach; (3) vertebral, anal atresia, cardiac, tracheoesophageal fistula, renal, and limb abnormalities; (4) first-degree relative with esophageal atresia; and (5) genetic mutation associated with esophageal atresia. In addition to dynamic esophageal patency assessment, a comprehensive anomaly scan was carried out. The fetal esophagus was observed during swallowing. Cases that demonstrated uninterrupted fluid propagation through the esophagus were classified as normal. Cases that demonstrated interrupted fluid propagation, with the formation of a pouch, were classified as abnormal. Cases with unclear visualization of the esophagus or cases that failed to demonstrate either fluid propagation or a pouch were classified as undetermined. Dynamic esophageal patency assessment results were compared with postnatal findings, considered "gold standard." Test performance indices and intra- and interobserver agreements were calculated.

RESULTS

For 12 months, 130 patients were recruited, and 132 fetuses were scanned. The median gestational age (interquartile range) at the time of scan was 31.4 weeks (29.0-35.3). Of 132 fetuses enrolled, 123 (93.2%) were normal, 8 (6%) were abnormal, and 1 (0.8%) was undetermined. Excluded from test performance analysis were 3 cases that were terminated without postmortem autopsy (1 was abnormal and 2 were normal), and a fourth case was excluded as it was classified as undetermined. The detection rate of esophageal atresia was 100%, with no false-positive or false-negative case. Sensitivity, specificity, and positive and negative predictive values of the dynamic esophageal patency assessment were 100%. The Kappa coefficient was 1 for both inter- and intraobserver agreements (P<.0001). The median time (interquartile range) required to complete the dynamic esophageal patency assessment was 6.00 minutes (3.00-13.25).

CONCLUSION

The dynamic esophageal patency assessment is a feasible and highly effective method of ascertaining an intact esophagus and detecting esophageal atresia in suspected cases.

Neonatal and Pediatric Bowel Obstruction: Imaging Guidelines and Recommendations

Pediatric bowel obstructions are one of the most common surgical emergencies in children, and imaging plays a vital role in the evaluation and diagnosis. An evidence-based and practical imaging approach to diagnosing and localizing pediatric bowel obstructions is essential for optimal pediatric patient care. This article discusses an up-to-date practical diagnostic imaging algorithm for pediatric bowel obstructions and presents the imaging spectrum of pediatric bowel obstructions and their underlying causes.

Esophageal atresia and tracheoesophageal fistula: prenatal sonographic manifestation from early to late pregnancy

OBJECTIVE

Esophageal atresia and/or tracheoesophageal fistula (EA/TEF) remains one of the most frequently missed congenital anomalies prenatally. The aim of our study was to elucidate the sonographic manifestation of EA/TEF throughout pregnancy.

METHODS

This was a retrospective study of data obtained from a tertiary center over a 12-year period. The prenatal ultrasound scans of fetuses with EA/TEF were assessed to determine the presence and timing of detection of three principal signs: small/absent stomach and worsening polyhydramnios, both of which were considered as 'suspected' EA/TEF, and esophageal pouch, which was considered as 'detected' EA/TEF. We assessed the yield of the early (14-16 weeks' gestation), routine mid-trimester (19-26 weeks) and third-trimester (≥ 27 weeks) anomaly scans in the prenatal diagnosis of EA/TEF.

RESULTS

Seventy-five cases of EA/TEF with available ultrasound images were included in the study. A small/absent stomach was detected on the early anomaly scan in 3.6% of fetuses scanned, without a definitive diagnosis. On the mid-trimester scan, 19.4% of scanned cases were suspected and 4.3% were detected. On the third-trimester anomaly scan, 43.9% of scanned cases were suspected and 33.9% were detected. An additional case with an esophageal pouch was detected on magnetic resonance imaging (MRI) in the mid-trimester and a further two were detected on MRI in the third trimester. In total, 44.0% of cases of EA/TEF in our cohort were suspected, 33.3% were detected and 10.7% were suspected but, eventually, not detected prenatally.

CONCLUSIONS

Prenatal diagnosis of EA/TEF on ultrasound is not feasible before the late second trimester. A small/absent stomach may be visualized as early as 15 weeks' gestation. Polyhydramnios does not develop before the mid-trimester. An esophageal pouch can be detected as early as 22 weeks on a targeted scan in suspected cases. The detection rates of all three signs increase with advancing pregnancy, peaking in the third trimester. The early and mid-trimester anomaly scans perform poorly as a screening and diagnostic test for EA/TEF. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Fetal esophageal imaging: Early pregnancy as a window of opportunity

OBJECTIVE

To describe the sonographic appearance of the fetal esophagus during early pregnancy and evaluate the feasibility of imaging the entire esophageal length. In addition, we present a case of disrupted esophageal continuity, subsequently diagnosed with esophageal atresia (EA).

METHODS

A prospective observational study of 145 patients. During the early second trimester anomaly scan performed at 12-17 weeks' gestation the entire esophagus was captured in a single sonographic image at the midsagittal plane (one shot technique). Postnatal follow-up of esophageal patency included review of medical records and telephone interviews.

RESULTS

Complete visualization of the esophagus (neck to diaphragm) was possible in 144 cases. In 88% of cases the esophagus was demonstrated by transvaginal approach. The time required to obtain the desired view of the esophagus, once the fetus was in an optimal position, was on average 13 s (range: 5-30 s). In one case at 15 weeks' gestation, the cervical segment of the esophagus was demonstrated while the lower thoracic segment was not identified. Subsequently EA was diagnosed.

CONCLUSIONS

It is feasible to demonstrate the entire esophagus during early second trimester anomaly scan. An early second trimester anomaly scan may serve as a window of opportunity for EA screening.

Prenatal ultrasonographic findings of esophageal atresia: potential diagnostic role of the stomach shape

Objective

We investigated prenatal sonographic characteristics of esophageal atresia (EA) with advancing gestation. We focused on the degree of polyhydramnios and the stomach shape.

Methods

This study included 27 EA cases (EA group) and 81 idiopathic polyhydramnios cases (non-EA group). The non-EA group consisted of cases without any fetal structural anomaly, musculoskeletal disorder, chromosomal abnormality, or maternal diabetes. Both groups included only singleton pregnancies. Amniotic fluid index (AFI) and width/length (W/L) ratio as well as the product of width and length (W×L) of stomach were serially assessed during gestation and compared between the 2 groups. To predict EA using W/L ratio and W×L, receiver operating characteristic curve analysis was performed.

Results

Polyhydramnios was evident in 77.8% of EA cases. We observed 25.9% and 22.2% EA cases with an absent stomach and a small visible stomach, respectively. After 28 weeks, the EA group manifested significantly higher AFI than the non-EA group. After 32 weeks, W/L ratio in the EA group tended to be lower than that in the non-EA group (32–36 weeks: 1.36 vs. 1.72, P=0.092; >36 weeks: 1.43 vs. 1.63, P=0.024). To predict EA, the calculated area under the curve for W/L ratio was 0.651 after 32 weeks. The diagnosis of EA using a cut-off value of W/L ratio <1.376 showed sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio to be 84.6%, 52.9%, 1.796, and 0.081, respectively.

Conclusion

A low W/L ratio of stomach after 32 weeks with progressive idiopathic polyhydramnios may be used to predict EA.

[Antenatal ultrasound prediction of esophageal atresia type]

BACKGROUND

Esophageal atresia (EA) is a rare congenital malformation of the upper aerodigestive tract, which can be diagnosed antenatally in 50-65% of cases. Postnatal management differs according to the type of EA. No studies have evaluated the correlation of antenatal ultrasound findings with the type of EA.

OBJECTIVE

The main objective is to study the association between antenatal ultrasound signs and the type of EA. The secondary objective is to study the association between postnatal morbidity and the type of EA.

METHOD

We conducted a single-center retrospective study between May 2010 and August 2019. Fetuses with suspected prenatal EA and postnatal diagnosis confirmation were included. Postnatal confirmation of EA was performed during surgery for live births and by fetopathological examination for termination of pregnancy. Prenatal signs and postnatal morbidity were compared according to the type of EA.

RESULTS

We included 15 cases of postnatally confirmed EA, including 9 type 1EA, 5 type 3EA and 1 type 4EA (11 live births and 4 terminations of pregnancy). The gestational age at diagnosis was earlier in type 1EA: 22⁺⁰ [6-21,21-24] versus 30⁺⁰ [28^+0-32⁺⁰] (P=0.03). Compared to type 3EA, type 1EA had a higher incidence of non-visible stomach bubble (89% versus 40%, P=0.09) and upper esophageal cul-de-sac dilatation (56% versus 0%, P=0.09). Neonatal morbidity in type 1EA was more severe with a longer hospital stay in neonatal intensive care.

CONCLUSION

The antenatal ultrasound signs seem to be more pronounced in case of type 1EA. Type 1EA is associated with severe morbidity compared to Type 3EA. Improving prenatal diagnosis of EA and its type allows a more accurate prognostic evaluation.

Sonographic demonstration of fetal esophagus using three-dimensional ultrasound imaging

OBJECTIVE

To evaluate the feasibility of antenatal direct visualization of normal and abnormal fetal esophagus using three-dimensional ultrasound (3D-US) with Crystal Vue rendering technology.

METHODS

Between February and April 2018, 3D-US volumes were collected from a non-consecutive series of singleton pregnancies, referred for clinically indicated detailed prenatal ultrasound at 19-28 weeks' gestation to one of two fetal medicine units in Italy. 3D volumes were acquired from a midsagittal section of the fetal thorax and upper abdomen with the fetus lying in supine position. Postprocessing with multiplanar mode was applied to orientate the volume and identify the esophagus. The region of interest was angled by approximately 30° to the spine and its thickness was adjusted in order to optimize visualization of the intrathoracic and intra-abdominal course of the esophagus. Crystal Vue software was used for image rendering of the fetal trunk in the coronal plane. Postnatal follow-up was available in all cases.

RESULTS

During the study period, 91 pregnancies met the inclusion criteria and were recruited. The study cohort included two pregnancies with suspicion of esophageal atresia due to suboptimal visualization of the stomach. Of the 89 cases with normal stomach on two-dimensional (2D) imaging, 3D-US with Crystal Vue rendering technology allowed direct evaluation of the whole course of the esophagus in 74 (83.1%). In the two cases with small or absent stomach bubble on 2D imaging, esophageal atresia was demonstrated antenatally on 3D Crystal Vue imaging and was confirmed postnatally. The mean time required for offline postprocessing and visualization of the esophageal anatomy was 4 min.

CONCLUSIONS

Using 3D-US with Crystal Vue rendering, it is possible to visualize antenatally the normal fetal esophagus and demonstrate presence of esophageal atresia. This should facilitate prenatal counseling and management of cases with suspected esophageal atresia. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

The Distended Fetal Hypopharynx: A Sensitive and Novel Sign for the Prenatal Diagnosis of Esophageal Atresia

BACKGROUND/PURPOSE

Although advances have been made in the prenatal diagnosis of esophageal atresia (EA), most neonates are not identified until after birth. The distended hypopharynx (DHP) has been suggested as a novel prenatal sign for EA. We assess its diagnostic accuracy and predictive value on ultrasound (US) and magnetic resonance imaging (MRI), both alone and in combination with the esophageal pouch (EP) and secondary signs of EA (polyhydramnios and a small or absent fetal stomach).

METHODS

We retrospectively reviewed fetal US and MRI reports and medical records of 88 pregnant women evaluated for possible EA from 2000 to 2016. Seventy-five had postnatal follow-up that confirmed or disproved the diagnosis of EA and were included in our analysis.

RESULTS

Seventy-five women had 107 study visits (range 1-4). DHP and/or EP were seen on US and/or MRI in 36% of patients, and 78% of those patients had EA. DHP was 24% more sensitive for EA than EP, while EP was 30% more specific. After 28weeks of gestation, DHP had a predictive accuracy for EA of 0.929 (P=0.001).

CONCLUSIONS

DHP is a sensitive additional prenatal sign of EA. More accurate diagnosis of EA allows for improved counseling regarding delivery, postnatal evaluation, and surgical correction.

TYPE OF STUDY

Diagnostic.

LEVEL OF EVIDENCE

Level II.

Long-Term Management Challenges in Esophageal Atresia

OPINION STATEMENT

Esophageal atresia is a rare congenital anomaly, but improved surgical and critical care has resulted in survival rates exceeding 90%. Long-term survival is associated with numerous management challenges including chronic motility disorders, dysphagia, strictures, reflux, esophagitis and attendant complications, tracheomalacia and chronic restrictive lung disease, and recurrent pulmonary infections. No guidelines for adolescents and younger or older adults exist for the treatment and monitoring of this specialized patient population. As such, patients with esophageal atresia can experience life-long sequelae of their disease and are best served by intentional transition to adult care for surveillance and monitoring, specifically for chronic lung disease, reflux, and its complications. This is best accomplished in a multidisciplinary fashion at experienced esophageal and lung centers.

Accuracy of prenatal detection of tracheoesophageal fistula and oesophageal atresia

AIMS

This study aims to determine the rate of prenatal detection of tracheoesophageal fistula and oesophageal atresia (TOF/OA), by identifying a small or absent stomach bubble with or without polyhydramnios, on the prenatal ultrasound scans (USS).

METHODS

A retrospective study of prenatal ultrasound findings of babies with a prenatal and postnatal diagnosis of TOF/OA born between 1st January 2004 and 31st December 2013 was undertaken.

RESULTS

A total of 58 babies were born with TOF/OA. 40% of mothers had their prenatal investigations performed within our tertiary centre, and the remaining 60% had their antenatal care at their local district general hospital (DGH). The overall sensitivity for prenatal USS was 26%, with a specificity of 99% and a positive predictive value (PPV) of 35%. However, the sensitivity of the prenatal USS within the tertiary centre was significantly higher at 57%, while only 2 cases were detected prenatally in the DGHs. Polyhydramnios was seen in 67% of mothers that had a prenatal diagnosis of TOF/OA and its presence did significantly increase the positive predictive value of prenatal USS (from 35% to 63%). Of those that were postnatally diagnosed, 21% had prenatal polyhydramnios. There was no significant difference in postnatal outcomes between those that were prenatally diagnosed and those that were postnatally diagnosed.

CONCLUSION

Prenatal diagnosis of TOF/OA remains challenging. However within a specialist centre the accuracy of successful prenatal detection can be significantly improved. This is beneficial both for prenatal counselling of families and for planning appropriate perinatal and postnatal care for the baby.

Oesophageal atresia: Diagnosis and prognosis in Dakar, Senegal

BACKGROUND

Oesophageal atresia is a neonatal emergency surgery whose prognosis has improved significantly in industrialised countries in recent decades. In sub-Saharan Africa, this malformation is still responsible for a high morbidity and mortality. The objective of this study was to analyse the diagnostic difficulties and its impact on the prognosis of this malformation in our work environment.

PATIENTS AND METHODS

We conducted a retrospective study over 4 years on 49 patients diagnosed with esophageal atresia in the 2 Paediatric Surgery Departments in Dakar.

RESULTS

The average age was 4 days (0-10 days), 50% of them had a severe pneumonopathy. The average time of surgical management was 27 h (6-96 h). In the series, we noted 10 preoperative deaths. The average age at surgery was 5.7 days with a range of 1-18 days. The surgery mortality rate is 28 patients (72%) including 4 late deaths.

CONCLUSION

The causes of death were mainly sepsis, cardiac decompensation and anastomotic leaks.

Integrative mid-trimester anomaly (IMTA) chart: a novel sonographic approach for syndromatic challenges (pilot study)

OBJECTIVE

To validate the use of the integrative mid-trimester anomaly (IMTA) chart, a novel chart that aims to increase sonographers' ability to diagnose fetal syndromes and complex anomalies.

METHODS

This study was conducted between September 2014 and January 2015. Pregnant women who attended our hospital for fetal medicine consultation during the second trimester were recruited. The diagnosis was assigned by a qualified consultant. The research coordinator randomized women between two groups (each consisted of two sonographers with comparable experience) and each was then examined twice (once with and once without the chart). Supposed diagnosis, patient and sonographer satisfactions were reported.

RESULTS

Twenty five women were recruited. Their average age was 26.48 ± 4.49 years and gestational age at examination was 24.39 ± 6.39. There were 17 (68%) fetuses that had multiple anomalies. The duration of examination was comparable. However, patient and sonographer satisfactions were higher when the same women were examined with the chart (p < 0.0001). The accuracy of diagnosis was also significantly higher (p = 0.03).

CONCLUSION

The IMTA chart seems to be a useful tool for novice sonographers that could increase their diagnostic accuracy and improve their patient and their own satisfaction.

Does prenatal diagnosis modify neonatal treatment and early outcome of children with esophageal atresia?

OBJECTIVE

Our study aimed at (1) evaluating neonatal treatment and outcome of neonates with either a prenatal or a postnatal diagnosis of esophageal atresia (EA) and (2) analyzing the impact of prenatal diagnosis on outcome based on the type of EA.

STUDY DESIGN

We conducted a population-based study using data from the French National Register for infants with EA born from 2008-2010. We compared prenatal, maternal, and neonatal characteristics among children with prenatal vs postnatal diagnosis and EA types I and III. We defined a composite variable of morbidity (anastomotic esophageal leaks, recurrent fistula, stenosis) and death at 1 year.

RESULTS

Four hundred sixty-nine live births with EA were recorded with a prenatal diagnosis rate of 24.3%; 82.2% of EA type I were diagnosed prenatally compared with 17.9% of EA type III (P < .001). Transfer after birth was lower in case of prenatal diagnosis (25.6% vs 82.5%; P < .001). The delay between birth and first intervention did not differ significantly among groups. The defect size was longer among the prenatal diagnosis group (2.61 vs 1.48 cm; P < .001). The composite variables were higher in prenatal diagnosis subset (44% vs 27.6%; P = .003) and in EA type I than in type III (58.1% vs 28.3%; P < .001).

CONCLUSION

Despite the excellent survival rate of EA, cases with antenatal detection have a higher morbidity rate related to the EA type (type I and/or long gap). Even though it does not modify neonatal treatment and the 1-year outcome, prenatal diagnosis allows antenatal parental counselling and avoids postnatal transfers.

The diagnosis of fetal esophageal atresia and its implications on perinatal outcome

The current diagnostic accuracy and perinatal outcome of fetuses with esophageal atresia (EA) continues to be debated. In this review, we report on our experience at a tertiary care fetal center with the prenatal ultrasound diagnosis of EA. Enrollment criteria included a small/absent stomach bubble with a normal or elevated amniotic fluid index between 2005 and 2013. Perinatal outcomes were analyzed and compared to postnatally diagnosed EA cases. Of the 22 fetuses evaluated, polyhydramnios occurred in 73%. Three (14%) died in utero or shortly after birth, but none had EA. In the presence of an absent/small stomach and polyhydramnios, the positive predictive value for EA was 67%. In fetal EA cases confirmed postnatally (group 1, n = 11), there were no differences in gestational age, birthweight, or mortality when compared to postnatally diagnosed infants (group 2, n = 59). Group 1 was associated with long-gap EA, need for esophageal replacement, and increased hospital length of stay. When taken in context with the current literature, we conclude that ultrasound findings suggestive of EA continue to be associated with a relatively high rate of false positives. However, among postnatally confirmed cases, there is an increased risk for long-gap EA and prolonged hospitalization.

Fetal MRI improves diagnostic accuracy in patients referred to a fetal center for suspected esophageal atresia

PURPOSE

The purpose of this study was to describe prenatal imaging characteristics and outcomes of fetuses with suspected esophageal atresia (EA) in order to improve prenatal diagnosis, counseling, and management.

METHODS

The medical records of all patients referred to our multidisciplinary fetal center for suspected EA from January 2003 to April 2013 were reviewed retrospectively.

RESULTS

Thirty-three patients were referred with a prenatal diagnosis of possible EA. Following fetal center evaluation with MRI, EA was deemed unlikely in 6 (18%) fetuses. Of 27 fetuses in whom EA could not be excluded, EA was confirmed postnatally in 15 (56%), excluded in 7 (26%), and unconfirmed in 5 (3 fetal losses; 2 lost to follow-up). Imaging characteristics on fetal MRI associated with the highest positive predictive values (PPV) were an esophageal pouch (100%) and a small stomach (75%). The finding of polyhydramnios had high sensitivity (93%) but low specificity (31%) and PPV (61%) for a diagnosis of EA.

CONCLUSION

Prenatal imaging and fetal center evaluation correctly identify the presence or absence of esophageal atresia in 78% of patients referred on suspicion of this condition. The presence of an esophageal pouch on fetal MRI has significant predictive value for EA. These data may assist with evidence-based prenatal family counseling.

[Esophageal atresia: prevalence, prenatal diagnosis and prognosis]

Esophageal atresia (EA) is a rare congenital malformation (1 in 2,500 to 3,500 births). Prenatal diagnosis (PN) is particularly interesting allowing search for associated malformations related to worse prognosis forms (reference ultrasound, MRI and amniocentesis) and planning the birth in an adapted medico-surgical center. Diagnosis of EA is usually suspected because of indirect and non-specific signs: association of polyhydramnios and absent or small stomach bubble. The visualization in ultrasound or MRI of cervical or thoracic fluid image corresponding to the expansion of the bottom of upper esophageal ("pouch sign") increases the specificity of diagnosis. However, prenatal diagnosis remains difficult and less than 50 % of EA are diagnosed prenatally. Biochemical analysis could improve these results. If EA is confirmed at birth, surgical management consists in a primary end-to-end anastomosis in first days of life, or in two-steps surgery if the defect is too large. Although current prognosis of EA is good, frequency of surgical complications and esophageal lesions secondary to gastroesophageal reflux justify a systematic and multidisciplinary extended follow-up.

Surgical advances in the fetus and neonate: esophageal atresia

This article focuses on selected topics in the diagnosis and management of patients with esophageal atresia (EA) with or without tracheoesophageal fistula. The current status of prenatal diagnosis and recent advances in surgical techniques, including thoracoscopic repair for short-gap EA and tension-induced esophageal growth for long-gap EA, are reviewed. Although no consensus exists among pediatric surgeons regarding the role of these procedures in the treatment of EA, one can reasonably expect that, as they evolve, their application will become more widespread in this challenging patient population.

Biochemical amniotic fluid pattern for prenatal diagnosis of esophageal atresia

Prenatal diagnosis of esophageal atresia (EA) may improve the outcome of affected neonates by allowing optimization of both prenatal and postnatal care. Prenatal sonographic detection is based on polyhydramnios and/or nonvisualization of the fetal stomach bubble, two signs with a large number of etiologies. We evaluated a biochemical approach to improving diagnostic efficiency. We compared amniotic fluid biochemical markers in 44 EA cases with 88 polyhydramnios and 88 nonpolyhydramnios controls. Both matched for GA with cases. Total proteins, alpha-fetoprotein (AFP), and digestive enzyme activities were assayed, including gamma-glutamyl transpeptidase (GGTP). We defined an EA index (AFP multiplied by GGTP). A significant difference (p < 0.0001) was observed for total protein, AFP, GGTP, and EA index between the EA group and each of the two control groups. No statistical difference was observed for any marker between the two most frequent EA subgroups (type I and type III) or between the two control groups. Using a cutoff of 3 for the EA index, 98% sensitivity and 100% specificity were observed for amniotic fluid prenatal diagnosis of EA, whatever the anatomical type. A large prospective series is required to confirm these results.

Pre- and postnatal diagnosis and outcome of fetuses and neonates with esophageal atresia and tracheoesophageal fistula

OBJECTIVES

Clinical symptoms and ultrasound signs during pregnancy could suggest the presence of esophageal atresia (EA). However, most often EA is diagnosed postnatally. The aim of our study is to evaluate the course and outcome for prenatally and postnatally diagnosed EA. In addition, we studied the outcome of isolated versus nonisolated EA.

METHODS

In a retrospective data analysis, ultrasound characteristics, maternal and neonatal variables as well as clinical outcome were compared for fetuses/neonates with prenatal (n = 30) or postnatal (n = 49) diagnosis of EA. Clinical outcome in terms of morbidity and mortality of isolated EA was compared with that of EA complicated by chromosomal or structural anomalies.

RESULTS

Prenatally diagnosed children were born 2 weeks earlier than postnatally diagnosed children (36.4 weeks vs 38.2 weeks; P = 0.02). The former had higher mortality rates (30 vs 12%; P = 0.05) and more associated anomalies (80 vs 59%; P = 0.04). In both subsets, there was a high morbidity rate in the survivors (not significant). Nonisolated EA was associated with greater occurrence of polyhydramnios (53 vs 27%; P = 0.04) and higher mortality rate (28 vs 0%; P = 0.002).

CONCLUSIONS

Mortality was significantly higher in prenatally diagnosed infants and in infants with additional congenital anomalies. Isolated EA is associated with good outcome.

Current status of prenatal diagnosis, operative management and outcome of esophageal atresia/tracheo-esophageal fistula

Ultrasonographic features suggestive of esophageal atresia with or without tracheo-esophageal fistula (EA/TEF) are only in a small minority of fetuses with EA/TEF (<10%) identifiable on prenatal scans.The prenatal diagnosis of EA/TEF relies in principle, on two nonspecific signs: polyhydramnios and absent or small stomach bubble. Polyhydramnios is associated with a wide range of fetal abnormalities, but most commonly it pursues a benign course. Similarly the sonographic absence of a stomach bubble may point to a variety of fetal anomalies.The combination of polyhydramnios and absent stomach bubble in two small series offers a modest positive predictive value of 44 and 56% respectively. Prenatal scanning for EA/TEF identifies a larger proportion of fetuses with Edwards syndrome; there is also a higher proportion of isolated EA in comparison to postnatal studies.Current ultrasound technology does not allow for a definite diagnosis of EA/TEF and therefore, counseling of parents should be guarded.Postnatal diagnosis of EA is confirmed by the failure to pass a firm nasogastric tube into the stomach; on chest X-ray, the tube is seen curling in the upper esophageal pouch. Corrective surgery for EA/TEF is well established and survival rates of over 90% can be expected.

Three- and four-dimensional ultrasound: new methods for evaluating fetal thoracic anomalies

OBJECTIVE

To study three- (3D) and four-dimensional (4D) ultrasound applications for the evaluation of fetal thoracic anomalies.

METHODS

Volume datasets of 23 fetuses with thoracic anomalies were acquired with static 3D and cine 4D ultrasound, i.e. spatiotemporal image correlation (STIC) mode. The volumes were analyzed and displayed by multiplanar and tomographic ultrasound imaging (TUI) modes and static volume contrast imaging (VCI). Color Doppler was added to the volumes acquired, and various rendering modes were used to display the volume datasets.

RESULTS

The mean gestational age at evaluation was 22 (range, 14-34) weeks. The anomalies were identified as: diaphragmatic hernia (n = 5), lung dysplasia (n = 11), skeletal dysplasia with small thorax/thanatophoric dysplasia (n = 2), abnormal situs (n = 2), hydrothorax (n = 2) and esophageal atresia (n = 1). The TUI mode achieved optimal display of the thorax, thereby aiding the diagnosis of diaphragmatic hernia and lung dysplasia. In right diaphragmatic hernias, the VCI mode proved invaluable as it distinguished liver from lung tissue. High-definition color Doppler with glass-body rendering significantly contributed to the detection of abnormal vascularization in lung dysplasia. Maximal transparent mode with a transvaginal transducer provided accurate diagnosis of skeletal dysplasia in the first trimester. Situs abnormalities were best viewed with a minimal transparent mode, in which abnormal organs and positions of vessels were clearly identified. Pleuroamniotic shunt localization was monitored precisely by 3D in a fetus with hydrothorax, and inversion mode added important information regarding the size of an esophageal pouch in a fetus with esophageal atresia.

CONCLUSION

The 3D-4D technique is a novel, useful sonographic tool for evaluating the fetal thorax. It enhances precise diagnosis and provides better spatial visualization of the anomalies involved.

Nomograms of the fetal neck circumference and area throughout gestation

OBJECTIVE

The purpose of this study was to create reference range nomograms of the axial fetal neck circumference (FNC) and fetal neck area (FNA) throughout gestation.

METHODS

This prospective cross-sectional study involved pregnant patients between 14 and 40 weeks' gestation. Inclusion criteria consisted of well-established dates (confirmed by early sonography) and nonanomalous singleton fetuses with intact fetal membranes. Sonographic measurements included biparietal diameter, head circumference, abdominal circumference, femur length, humerus length, transcerebellar diameter, and sonographically estimated fetal weight. Axial FNC and FNA values were calculated as means of 3 separate measurements. The 5th, 50th, and 95th percentiles were estimated at each week of gestational age (GA) by least squares regression for the mean and SD of the FNC and FNA as functions of GA. R(2) and associated P values for the relationships between the FNC, FNA, and other sonographic biometric measurements were calculated.

RESULTS

The study included 720 consecutive patients. The mean maternal age +/- SD was 27.3 +/- 6.6 years; median gravidity, 3 (range, 1-13); and median parity, 1 (range, 0-10). The following equations were devised: mean FNC (centimeters) = -11.85 + 1.687 x GA (weeks) -0.043 x GA(2) + 0.0004951 x GA(3); SD(FNC) = 3.15 - 0.3823 x GA + 0.01733 x GA(2) - 0.0002179 x GA(3); mean FNA (square centimeters) = 37.29 - 7.0 x GA + 0.4717 x GA(2) - 0.01245 x GA(3) + 0.0001222 x GA(4); and SD(FNA) = 7.08 - 0.9413 x GA + 0.04135 x GA(2) - 0.0004829 x GA(3). Both the FNC and FNA correlated significantly and strongly with biparietal diameter, head circumference, abdominal circumference, humerus length, femur length, transcerebellar diameter, and sonographically estimated fetal weight.

CONCLUSIONS

Current nomograms of the axial FNC and FNA throughout gestation have been provided.

Prenatal diagnosis of tracheo-oesophageal fistula and oesophageal atresia

OBJECTIVES

To assess the accuracy of the prenatal ultrasound finding of subjectively small/absent stomach bubble in the prenatal diagnosis of tracheo-oesophageal fistula and oesophageal atresia (TOF/OA).

METHODS

A retrospective study of prenatal ultrasound scans showing small/absent stomach bubble was carried out between 1st January 1994 and 31st December 2003.

RESULTS

There were 62 cases with prenatally suspected (n = 40) and/or post-natally diagnosed (n = 22) TOF/OA. Among the 40 cases of prenatally suspected TOF/OA 15 were thought to be isolated and 25 non-isolated. Of the 15 suspected isolated cases, 7 were normal and 8 had TOF/OA (5 isolated + 3 TOF/OA with another anomaly) at delivery. Among the 25 cases of prenatally suspected non-isolated TOF/OA, there was confirmation in only two cases, in the remaining 23 cases other anomalies were confirmed but TOF/OA was not present.Twenty-two babies with TOF/OA were identified in whom there had been no prenatal ultrasound suspicion on ultrasound scanning. Six had isolated TOF/OA and 16 had non-isolated TOF/OA.

CONCLUSION

Of the 32 cases of confirmed TOF/OA,10 (31%) were suspected prenatally. If the TOF/OA was an isolated anomaly (11 cases), the prenatal detection rate was 45%. Interpretation of ultrasound findings suspicious of TOF/OA requires caution, particularly, when there are associated multiple anomalies on scan.

Esophageal obstruction-prenatal detection rate and outcome

OBJECTIVE

Prenatal diagnosis of esophageal obstruction is believed to improve the outcome for the affected newborn. However, the prenatal detection rate is only 10-40%, the diagnosis is usually not made before the third trimester and the false-positive rate has been high. This study investigated the prenatal detection rate and time of prenatal diagnosis at our center and its influence on outcome. In addition, incidence, detection rate and accuracy of the diagnosis in a large non-selected population were determined.

METHODS

All cases diagnosed pre- or postnatally with esophageal obstruction and examined prenatally by ultrasound at the National Center for Fetal Medicine in Norway during 1987-2004 were evaluated.

RESULTS

Of 48 cases with esophageal obstruction, 21 (44%) were diagnosed prenatally (median, 32 + 0 weeks). All 21 had a small or empty stomach, 20/21 (95%) had polyhydramnios and 9/21 (43%) had a visible esophageal pouch. Associated anomalies were present in 38/48 cases (79%). The karyotype was abnormal in 11/48 cases (23%). Ten (21%) pregnancies with lethal fetal conditions were terminated. Two fetuses died in utero. Ten infants with associated anomalies died within 3 months after birth. The 26/48 (54%) survivors included 16/21 cases with a prenatal diagnosis of esophageal obstruction and 9/10 cases with isolated esophageal obstruction.

CONCLUSIONS

The clinical signs of polyhydramnios were the most important factors for prenatal detection of esophageal obstruction. Consequently, the time of diagnosis was late and the detection rate was low (44%). An increased awareness of the possibility of esophageal obstruction, leading to targeted examinations whenever the suspicion is raised during pregnancy, might improve the prenatal detection rate and thereby provide a possibility to improve the outcome. Of the cases with isolated esophageal obstruction, 90% survived, irrespective of prenatal diagnosis.

Oesophageal atresia

Oesophageal atresia (OA) encompasses a group of congenital anomalies comprising of an interruption of the continuity of the oesophagus with or without a persistent communication with the trachea. In 86% of cases there is a distal tracheooesophageal fistula, in 7% there is no fistulous connection, while in 4% there is a tracheooesophageal fistula without atresia. OA occurs in 1 in 2500 live births. Infants with OA are unable to swallow saliva and are noted to have excessive salivation requiring repeated suctioning. Associated anomalies occur in 50% of cases, the majority involving one or more of the VACTERL association (vertebral, anorectal, cardiac, tracheooesophageal, renal and limb defects). The aetiology is largely unknown and is likely to be multifactorial, however, various clues have been uncovered in animal experiments particularly defects in the expression of the gene Sonic hedgehog (Shh). The vast majority of cases are sporadic and the recurrence risk for siblings is 1%. The diagnosis may be suspected prenatally by a small or absent stomach bubble on antenatal ultrasound scan at around 18 weeks gestation. The likelihood of an atresia is increased by the presence of polyhydramnios. A nasogastric tube should be passed at birth in all infants born to a mother with polyhydramnios as well as to infants who are excessively mucusy soon after delivery to establish or refute the diagnosis. In OA the tube will not progress beyond 10 cm from the mouth (confirmation is by plain X-ray of the chest and abdomen). Definitive management comprises disconnection of the tracheooesophageal fistula, closure of the tracheal defect and primary anastomosis of the oesophagus. Where there is a "long gap" between the ends of the oesophagus, delayed primary repair should be attempted. Only very rarely will an oesophageal replacement be required. Survival is directly related to birth weight and to the presence of a major cardiac defect. Infants weighing over 1500 g and having no major cardiac problem should have a near 100% survival, while the presence of one of the risk factors reduces survival to 80% and further to 30–50% in the presence of both risk factors.

[Gastric lavage in healthy term newborns: a randomized controlled trial]

INTRODUCTION

Gastric lavage is still used in Mexico and other countries without evidence to support this practice. We performed a randomized controlled trial to test the hypothesis that elimination of amniotic fluid from the stomach of the newborn reduces nausea and vomiting and improves tolerance on the first feedings of breast or formula milk.

PATIENTS AND METHODS

A randomized, single-blind, controlled trial was conducted in a rural general hospital in the north of Mexico. Eligible healthy term newborns were randomly allocated to receive gastric lavage (n = 63) or observation (n = 61). The primary outcome measures were the presence of nausea and/or emesis in the first 24 hours of life and the breastfeeding failure rate, evaluated by a nurse blinded to the group assignment.

RESULTS

Of the 63 patients in the gastric lavage group, 13 had at least one episode of nausea or vomiting compared with 15 out of 61 patients in the control group (relative risk: 0.84; 95 % CI: 0.43 to 1.61). Breastfeeding failure occurred in seven mother-child pairs in the gastric lavage group compared with five in the control group (P = 0.8; relative risk: 0.96; 95 % CI: 0.86 to 1.08). Other variables such as sex or cesarian section rate were unrelated to outcome. There were no complications that could be attributed to the procedure. All the newborn infants were discharged without problems.

CONCLUSIONS

Gastric aspiration or lavage in the healthy full-term newborn is a common procedure that should be abandoned as it confers no advantages.

[Prenatal MRI diagnosis of esophageal atresia]

The diagnosis of esophageal atresia may be suspected on prenatal ultrasonography in fetuses with absent or small stomach, upper esophageal dilatation and unexplained polyhydramnios. However, the diagnostic value of these findings is relatively poor. Two cases are reported where MRI appeared to be accurate for establishing the diagnosis of this congenital anomaly.

The fetal esophagus: anatomical and physiological ultrasonographic characterization using a high-resolution linear transducer

OBJECTIVE

To study the sonographic anatomy and physiology of the human fetal esophagus during the mid-trimester of pregnancy using a high-resolution linear transducer.

METHODS

This was a prospective observational study of the fetal esophagus between 19 and 25 weeks' gestation. The study was performed in 60 consecutive fetuses, after a normal anatomy scan, using a 5-13-MHz matrix array wide-band transducer. During the examination the collapsed esophagus was first visualized, and followed by a 5-min video recording in order to demonstrate luminal patency and peristaltic waves.

RESULTS

Complete anatomical visualization of the esophagus was possible in 52 (86.7%) patients and at least partial visualization in 58 (96.7%) patients. Three different patterns of esophageal motility were observed: a simultaneous and short opening of the whole esophagus was found in 35 (58.3%) fetuses; a segmental, peristalsis-like movement from the pharynx, through the mediastinum, and into the stomach was found in 18 (30%) fetuses; and in one fetus reflux-like passage of solid contents from the stomach was observed. The mean time required for demonstration of esophageal patency was 96.1 (range, 10-300) s.

CONCLUSIONS

Demonstration of normal anatomy and physiological activity of the fetal esophagus is feasible using appropriate transducers. The most commonly observed pattern of esophageal motility in the mid-trimester of pregnancy is the simultaneous relaxation of the upper and lower esophageal sphincters with concurrent opening of the esophageal lumen from the upper thorax to the stomach. Demonstration of a patent esophagus may be helpful in fetuses with suspected esophageal atresia.

Congenital abnormalities of the musculoskeletal system: Perinatal evaluation and long-term outcome

Many musculoskeletal malformations can be detected by prenatal US. Whether isolated or part of a syndrome, these anomalies can have a significant impact on the entire life of the individual. Nonfatal conditions may be subtle and become more recognizable in the second and third trimester. After delivery, radiography helps confirm the diagnosis. US, CT, and MRI all have a role in imaging the primary abnormality, the follow-up effects of treatment, and in monitoring for potential complications that may develop over time. Three-dimensional imaging has an increasing role, in US, CT, and MRI, both in the prenatal and postnatal periods.

Prenatal diagnosis of esophageal atresia with the pouch sign

A 19-year-old primipara was referred to our center for a routine scan at 33 + 4 weeks' gestation. A visible but small stomach bubble (18 mm) was detected in the fetal abdomen, associated with a dilation of the esophagus with a tapering distal part. Direct visualization of filling and emptying of the proximal esophagus suggested the presence of obstruction. A cystic pouch in the region of the esophagus was observed to be full and empty in accordance with fetal swallowing. No other fetal anomalies were detected. Fetal biometric measurements were on the 10th percentile and polyhydramnios was detected. Esophageal atresia type I was suspected. Fetal karyotyping was declined by the parents, no therapy was given and the pregnancy continued until week 37 when a female baby was delivered following spontaneous labor. Esophageal atresia type I was radiographically confirmed. Bougienage was used for 8 weeks and esophageal anastomosis was successfully performed when the infant was 11 months old. No other anomalies were found and the child is currently in excellent health. The present case shows that the upper neck pouch sign may be a delayed manifestation present only in certain types of esophageal atresia. However, when it occurs it should prompt careful fetal examination as it is an important step in the diagnosis of esophageal atresia.