Ultrasound Obstet Gynecol 2004; 23: 523–526 Published online in Wiley InterScience (www.interscience.wiley.com).
Letters to the Editor
Pouch sign in prenatal diagnosis of esophageal atresia Visualization of a pouch in the fetal neck or mediastinum during fetal swallowing has been proposed for the prenatal diagnosis of esophageal atresia1 – 4 . This is a reliable finding and all reported cases with a blind-ending pouch in the neck have subsequently been confirmed to have esophageal atresia. However, possibly due to the technical difficulties involved in the visualization of the pouch, only 12 cases have been reported to date1 – 5 . The pouch sign may also be useful in the determination of postnatal outcome. We have diagnosed two new cases of congenital esophageal atresia by detecting an upper neck pouch sign, and here we discuss the prognostic value of this finding according to the location of the pouch. Our first case was a 36-year-old woman, gravida 3 para 2, with gestational diabetes who was referred to our unit in the 34th week of pregnancy with severe polyhydramnios. The fetal stomach was small and the abdominal circumference was below the 10th percentile. We detected a 13-mm pouch in the upper mediastinum during fetal swallowing (Figure 1). There was no other associated fetal abnormality and no chromosomal abnormality. A 2700-g girl, measuring 47 cm in length and with Apgar scores of 9 and 10 at 1 and 5 min, respectively, was delivered vaginally in the 37th week. Barium radiography showed esophageal atresia without a fistula (Figure 2). On day 2 postpartum simple primary anastomosis was accomplished, and after an uneventful recovery, the infant was discharged on the 13th postoperative day. In our second case the mother was 22 years old, gravida 2 para 1, and in the 31st week of pregnancy. Sonographic
Figure 1 Sonographic appearance of an esophageal pouch in the mediastinum during fetal swallowing (Case 1).
Copyright 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Figure 2 Barium radiography of an esophageal pouch at the level of the third rib in the mediastinum (Case 1).
examination showed severe polyhydramnios and the absence of a fetal stomach. During fetal swallowing we observed a pouch, measuring 20 × 18 mm, at the upper level of the neck (Figure 3). We performed amniodrainage and obtained a normal karyotype result. Due to the onset of preterm labor in the 34th week of gestation a 1900-g male with Apgar scores of 8 and 9 at 1 and 5 min, respectively, was delivered. Barium radiography showed the exact level of the proximal esophageal obstruction (Figure 4). An operation was performed on the infant on day 2 after birth. The distance between the proximal and distal segments of the esophagus was too long to attempt a primary anastomosis. The stomach was left open, and from the gastrostomy opening, the distal end of the esophagus was pushed up with a Hegar dilator to elongate this segment. A month later a second operation was attempted. This time, a thoracotomy was performed and a subtle fistula was detected, between the blind proximal esophagus and the trachea, and ligated. Again esophageal anastomosis could not be achieved. Transplantation of a segment of colon was planned for the next intervention.
LETTERS TO THE EDITOR
Letters to the Editor
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Figure 3 Sonographic appearance of an esophageal pouch in the neck (Case 2).
after a successful corrective operation, and primary repair was possible in all cases. However, in three fetuses with a neck pouch only one survived, after a staged repair. They concluded that if the pouch is in the upper neck, it is more likely to be associated with a long atretic gap, making approximation of the esophageal endings more difficult. In our first case, the pouch was in the mediastinum, with a short atretic segment of the esophagus, and a successful primary anastomosis was accomplished without complications. However, in the second case, the pouch was located in the neck and there was a long atretic gap between the pouch and the distal ending of the esophagus, making anastomosis impossible despite two operations. Our two cases support the hypothesis of Kalache et al.5 . Interestingly, the incidence of the pouch sign in the diagnosis of congenital esophageal atresia is underreported. This may be due to the technical difficulties in visualization, or to examination prior to the 26th week of gestation. Also, the fetus may not swallow during the examination. Failure to identify a pouch in the fetal neck does not exclude esophageal atresia. In suspected cases, careful examination of the fetal neck for the identification and location of the pouch sign is recommended. The presence of a neck pouch not only provides a more reliable diagnosis of esophageal atresia, it also assists physicians in predicting the prognosis, and counseling the parents. ¨ R. Has*, S. Gunay and S. Topuz Faculty of Medicine, University of Istanbul, Department of Obstetrics and Gynecology, Istanbul, Turkey *Correspondence. (9. Kısım B-18 Daire 52, 34750 Atakoy, Istanbul, Turkey e-mail:
[email protected]) DOI: 10.1002/uog.1041 Published online 7 April 2004
References Figure 4 Barium radiography of an esophageal pouch above the level of the clavicle (Case 2).
The mother was instructed to feed the baby from the gastrostomy opening and the infant was discharged on the 20th postoperative day. Esophageal atresia is perceived to be a relatively benign abnormality with good outcome. However, perinatal mortality is high, especially in those cases diagnosed prenatally. This is probably due to the higher incidence of associated malformations in prenatally diagnosed cases6 . It has been proposed that the upper neck pouch sign may be valuable in predicting the postnatal outcome of affected fetuses5 . Kalache et al. analyzed their four cases and three other reports from the literature, and suggested an association between the location of the pouch and the prognosis5 . In the seven cases they analyzed, three of the four fetuses with a mediastinal pouch survived
Copyright 2004 ISUOG. Published by John Wiley & Sons, Ltd.
1. Eyheremendy E, Pfister M. Antenatal real-time diagnosis of esophageal atresias. J Clin Ultrasound 1983; 11: 395–397. 2. Satoh S, Takashima T, Takeuchi H, Koyanagi T, Nakano H. Antenatal sonographic detection of the proximal esophageal segment: specific evidence for congenital esophageal atresia. J Clin Ultrasound 1995; 23: 419–423. 3. Vijayaraghavan SB. Antenatal diagnosis of esophageal atresia with tracheoesophageal fistula. J Ultrasound Med 1996; 15: 417–419. 4. Kalache KD, Chaoui R, Mau H, Bollmann R. The upper neck pouch sign: a prenatal sonographic marker for esophageal atresia. Ultrasound Obstet Gynecol 1998; 11: 138–140. 5. Kalache KD, Wauer R, Mau H, Chaoui R, Bollmann R. Prognostic significance of the pouch sign in fetuses with prenatally diagnosed esophageal atresia. Am J Obstet Gynecol 2000; 182: 978–981. 6. Desmedt E, Henry O, Beischer N. Polyhydramnios and associated maternal and fetal complications in singleton pregnancies. Br J Obstet Gynaecol 1990; 97: 1115–1122.
Ultrasound Obstet Gynecol 2004; 23: 523–526.
