You are in: eMedicine Specialties > Radiology > PEDIATRICS Congenital Diaphragmatic HerniaArticle Last Updated: Jul 16, 2008AUTHOR AND EDITOR INFORMATIONAuthor: Ali Hekmatnia, MD, Associate Professor, Department of Pediatric Radiology, Isfahan University of Medical Sciences, Iran; Consulting Staff, Department of Radiology, Al-Zahra Hospital, Iran Coauthor(s): Kieran McHugh, MBBCh, Honorary Lecturer, The Institute of Child Health; Consultant Pediatric Radiologist, Department of Radiology, Great Ormond Street Hospital for Children, London, UK Editors: S Bruce Greenberg, MD, Professor of Radiology, University of Arkansas for Medical Sciences; Consulting Staff, Department of Radiology, Arkansas Children's Hospital; Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand; David A Stringer, BSc, MBBS, FRCR, FRCPC, Professor, National University of Singapore; Head, Diagnostic Imaging, KK Women's and Children's Hospital, Singapore; Robert M Krasny, MD, Consulting Staff, Department of Radiology, The Angeles Clinic and Research Institute; Eugene C Lin, MD, Clinical Assistant Professor of Radiology, University of Washington Medical School Author and Editor Disclosure Synonyms and related keywords: congenital diaphragmatic hernia, CDH, Bochdalek hernia, posterolateral Bochdalek hernia, anterior Morgagni hernia, hiatus hernia, hiatal hernia INTRODUCTIONBackgroundIntroduction Congenital diaphragmatic hernia (CDH) is a major surgical emergency in newborns. The key to survival lies in prompt diagnosis and treatment. The symptoms of CDH depend on the degree of herniation; small hernias may initially pass unnoticed, whereas larger ones produce immediate and severe respiratory distress. History The topic of CDH has frequently appeared in medical literature since it was first described in 1679 by Lazarus Riverius, who incidentally noted a CDH during a postmortem examination of a 24-year-old person.1 In 1701, Sir Charles Holt described the classic clinical and postmortem findings of an infant with CDH in philosophical transactions of the Royal Society of London.1 In 1761, Giovanni Battista Morgagni reviewed the earlier literature and other accounts of both CDH and traumatic diaphragmatic hernias. He published his discussion along with the description of various types of diaphragmatic hernias in De Sedibus Et Causis Morborum Per Anatomen Indagatis Libri Quinique, which means "On the seats and causes of disease, investigated by anatomy". In this masterpiece, he described the classic anterior diaphragmatic hernia, which today bears his name—Morgagni hernia. In 1848, Victor Alexander Bochdalek, a professor of anatomy in Prague, described both right and left posterolateral CDH. To this day, CDH is commonly referred to as a Bochdalek hernia in honor of Victor Bochdalek's contributions to this field (see Diaphragmatic Hernias, Congenital). FrequencyUnited StatesCongenital diaphragmatic hernia occurs in 1 out of every 2000-4000 live births and accounts for 8% of all major congenital anomalies. InternationalWorldwide, the frequency of congenital diaphragmatic hernia is the same as that in the United States. Mortality/MorbidityMortality in babies with congenital diaphragmatic hernia is related to pulmonary hypoplasia, persistent fetal circulation (PFC), and associated anomalies.2, 3, 4, 5
RaceNo racial predilections have been noted in congenital diaphragmatic hernia . SexBenjamin et al reported a male preponderance in left-sided hernias, with a male-to-female ratio of 3:2. The incidence is even more striking in right-sided hernias, with a male-to-female ratio of 3:1.6 AnatomyThe diaphragm is the major muscle of respiration, and perhaps, it is the second most important muscle after the heart. When a decrease in diaphragmatic function occurs, concomitant respiratory dysfunction results (see Diaphragmatic Hernias, Congenital). Clinical DetailsCauses of CDHThe risk of recurrence of isolated congenital diaphragmatic hernia (CDH) for future siblings is approximately 2%. Familial CDH rarely occurs and may be caused by a multifactorial and/or threshold inheritance pattern. In some cases, an autosomal recessive pattern may be involved. CDH can also occur as a part of De Lange syndrome (an autosomal dominant disorder with microbrachycephaly and limb and digital anomalies) and as a part of Fryns syndrome (an autosomal recessive disorder with variable features that include diaphragmatic hernia, cleft lip and palate, and distal digital hypoplasia). CDH can occur in association with cardiovascular, genitourinary, and gastrointestinal malformations. Lethal anomalies are present in as many as 16% of infants. No single gene mutation has been identified as producing or contributing to this anomaly, although karyotype abnormalities have been reported in 4% of infants with CDH. CDH may be found in a variety of chromosomal anomalies, including trisomy 13, trisomy 18, and tetrasomy 12P mosaicism.5, 6 Classification of CDHThe 3 basic types of CDH are posterolateral Bochdalek hernia (occurring in utero at approximately 6 weeks of gestation), anterior Morgagni hernia, and hiatus hernia. Left-sided Bochdalek hernia is seen in approximately 90% of cases. The major problem in a Bochdalek hernia is the posterolateral defect of the diaphragm, which results in either failure of the pleuroperitoneal folds to develop or improper or absent migration of the diaphragmatic musculature. Bilateral Bochdalek hernias are rare.7 Morgagni hernia is a less common form of CDH, occurring in only 5-10% of cases. This hernia occurs in the anterior midline through the sternocostal hiatus of the diaphragm, with 90% of cases occurring on the right side. A congenital hiatus hernia is very rare in neonates. In this form, herniation of the stomach occurs through the esophageal hiatus. Complications of CDHPulmonary hypoplasia Pulmonary hypoplasia, which may be unilateral or bilateral, is a serious complication of CDH. This hypoplasia may result in a persistent fetal circulation (PFC).2 Pulmonary hypoplasia is thought to result from long-standing intrauterine (embryonic) compression of the lungs by the hernia. Mortality in babies with CDH is largely confined to those with bilateral pulmonary hypoplasia; however, hypoplasia is always more severe in the lung ipsilateral to the hernia. The pulmonary vasculature is also affected to a greater degree than the bronchial tree.2 Hypoplasia of the lungs is most severe in infants with the largest and longest-standing hernias; these infants are less likely to survive after birth. If a diaphragmatic hernia develops toward the end of pregnancy or after birth, pulmonary hypoplasia does not occur.5 Gastric volvulus Gastric volvulus can occur in early infancy as a complication of CDH, and it usually produces acute gastric obstruction. The radiographic findings usually consist of an inverted distended stomach. Rotational abnormalities and midgut volvulus Intestinal malrotation is commonly observed in children with CDH (30-62%); it occurs in 37-40% of the cases of right-sided CDH. Volvulus is a complication in a small minority of these cases.8 The radiographic findings of intestinal malrotation in CDH usually consist of a high gastrointestinal obstruction. The results of contrast-enhanced studies, either air or barium studies, confirm the level of obstruction, which is usually toward the third and fourth portions of the duodenum. If a midgut volvulus is present, a beaked or tapering deformity of the obstructed duodenum is seen. Similar findings can be demonstrated with ultrasonography.3 Gastric or other intestinal perforations Gastric or other intestinal perforations rarely occur. Hypoplasia of the left ventricle with a left-sided hernia or pleural effusions caused by right-sided involvement Pleural effusion is believed to result from lymphatic obstruction secondary to the compressive effects of the hernia. Bilateral renal hypertrophy The kidneys are often enlarged and hyperplastic.3 An embryonic liaison between the kidneys and the lungs has been suggested, wherein the kidney produces a pulmonary growth factor (proline) that influences normal lung development. Conversely, when the lung is hypoplastic, it produces a renotropic substance and causes the kidneys to hypertrophy. Preferred ExaminationImaging studies In the prenatal period, ultrasonography has a high sensitivity in the detection of congenital diaphragmatic hernia (CDH). Bowel loops may appear to undergo peristalsis in the chest.9 In the neonatal and infantile periods, the importance of obtaining a chest radiograph at the first sign of distress cannot be overstated. This image usually permits an accurate diagnosis, although sometimes plain abdominal radiography is also needed for a precise diagnosis. Typically, no bowel gas is evident in the abdomen. Radiologic features In patients presenting in the prenatal period, ultrasonographic features indicative of CDH include the following: polyhydramnios; an absent or intrathoracic stomach bubble; a mediastinal and cardiac shift away from the side of the herniation; and, rarely, fetal hydrops .9 In patients presenting in the neonatal and infantile periods, the classic radiographic appearance is one in which the left hemithorax is filled with cystlike structures (loops of bowel), the mediastinum is shifted to the right, and the abdomen is relatively devoid of gas.3 In some cases, a few loops of intestine can be seen in the abdomen, but more often only the stomach remains visible within the abdomen. Interestingly, the stomach may be in an abnormal location, often more central than one would expect. The abnormal positioning of the stomach may be helpful in differentiating CDH from those few cases of congenital cystic adenomatoid malformation (CCAM) in which the cysts are large enough to mimic the air-filled intestinal loops.3 In CCAM of the lungs, the stomach and bowel are normal in position and appearance. If the chest radiograph is obtained before any air has entered the herniated bowel, diagnosing this condition with accuracy may be difficult. Similar difficulties arise when the liver alone is in the right hemithorax. In either case, the involved hemithorax is partially or totally opacified, and the mediastinal structures are shifted to the other side. In this circumstance, a large pleural fluid collection or mass may be present; however, in most such cases, air soon enters the intestine, and this finding establishes the diagnosis. In other cases, the condition may be diagnosed by noting abnormal intrathoracic positioning of a nasogastric tube.3 Unusual findings include a contralateral pneumothorax, contralateral collapse/consolidation, fluid in the chest, and the absence of a contralateral aerated lung.3 If herniation occurs on the right, the intestine and liver or the liver alone may fill the right hemithorax. If the liver is in the chest, its normal silhouette is not generally seen in the abdomen. Morgagni hernias are usually asymptomatic in the infant. Classically, Morgagni hernias appear as unilateral, mediastinal, and basal masses containing a variety of abdominal organs, including air-filled loops of intestine. Occasionally, they may be bilateral, and in rare cases, they may produce significant respiratory distress. Large anterior-central diaphragmatic hernias may produce elevation of the cardiac silhouette and bilateral bulges to either side of the lower mediastinum. Often, these herniations occur into the pericardial cavity. When this occurs, serious cardiorespiratory compromise can result.3, 10 DIFFERENTIALS
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| Media file 1: Anteroposterior (AP) chest radiograph of a right-sided congenital diaphragmatic hernia (CDH) shows a mediastinal shift and lung compression caused by herniation of the liver and multiple bowel loops. | |
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| Media file 2: Anteroposterior (AP) chest radiograph of a right-sided congenital diaphragmatic hernia (CDH) shows herniation of the liver and bowel loops into the right hemithorax, with a shift of the heart and mediastinum to the left side. | |
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| Media file 3: Anteroposterior (AP) view of the abdomen in a patient with a congenital diaphragmatic hernia (CDH) shows a gasless pattern caused by herniation of bowel loops into the right hemithorax. | |
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| Media file 4: Anteroposterior (AP) view of the chest in a patient with a congenital diaphragmatic hernia (CDH) shows a left-sided Bochdalek hernia. | |
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| Media file 5: Anteroposterior (AP) view of the chest in a patient with a congenital diaphragmatic hernia (CDH) shows herniation of bowel loops into the left hemithorax, with a shift of the heart and mediastinum to the right side. | |
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| Media file 6: Sonogram of a right-sided congenital diaphragmatic hernia shows the liver herniating through the defect. | |
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Congenital Diaphragmatic Hernia excerpt
Article Last Updated: Jul 16, 2008