Mainstem bronchial atresia: a lethal anomaly amenable to fetal surgical treatment

Successful Postnatal Tracheobronchoplasty for Unilateral Congenital High Airway Obstruction Syndrome due to Mainstem Bronchial Atresia

INTRODUCTION

Unilateral congenital high airway obstruction syndrome (CHAOS) is caused by a complete obstruction of a mainstem bronchus with resulting hyperinflation and accelerated growth of one lung, severe mediastinal shift, and hydrops. Spontaneous perforation of the atresia has been observed in CHAOS which allows hydrops to resolve but hyperinflation, mediastinal shift and a critical airway obstruction persists as the perforation is usually pinhole-sized.

CASE PRESENTATION

We present a case of unilateral CHAOS presenting at 26 2/7 weeks with observed-to-expected total lung volume (O/E TLV) of 203% with spontaneous perforation occurring at 28 weeks with resolution of hydrops but persistence of hyperinflation and mediastinal shift with an O/E TLV of 60.5% on 34 5/7 weeks' magnetic resonance imaging (MRI), successfully managed in a 35 5/7 weeks, 1,670 gm, growth restricted baby, by venoarterial extracorporeal membrane oxygenation (VA ECMO) and resection of the tracheobronchial atresia and tracheobronchoplasty on day of life 5. The baby was separated from ECMO on post-op day 12, required tracheostomy for positive end expiratory pressure for tracheomalacia at 4 months.

CONCLUSION

At 2 years of age, she has met all developmental milestones, has been weaned to room air tracheostomy collar, and has been anticipating tracheal decannulation. There is persistent bronchiectasis in the hyperinflated right lung but no malacia. This is the first reported survivor of mainstem bronchial atresia suggesting the importance of preservation of the hyperplastic lung and airway reconstruction to normal long-term outcome.

Congenital Lung Malformations: Unresolved Issues and Unanswered Questions

Advances in prenatal and postnatal diagnosis, perioperative management, and postoperative care have dramatically increased the number of scientific reports on congenital thoracic malformations (CTM). Nearly all CTM are detected prior to birth, generally by antenatal ultrasound. After delivery, most infants do well and remain asymptomatic for a long time. However, complications may occur beyond infancy, including in adolescence and adulthood. Prenatal diagnosis is sometimes missed and detection may occur later, either by chance or because of unexplained recurrent or persistent respiratory symptoms or signs, with difficult implications for family counseling and substantial delay in surgical planning. Although landmark studies have been published, postnatal management of asymptomatic children is still controversial and needs a resolution. Our aim is to provide a focused overview on a number of unresolved issues arising from the lack of an evidence-based consensus on the management of patients with CTM. We summarized findings from current literature, with a particular emphasis on the vigorous controversies on the type and timing of diagnostic procedures, treatments and the still obscure relationship between CTM and malignancies, a matter of great concern for both families and physicians. We also present an algorithm for the assessment and follow-up of CTM detected either in the antenatal or postnatal period. A standardized approach across Europe, based on a multidisciplinary team, is urgently needed for achieving an evidence-based management protocol for CTM.

Fetal Congenital Peripheral Bronchial Atresia Diagnosed by Magnetic Resonance Imaging: Two Case Reports

Two types of congenital bronchial atresia (proximal and peripheral) have been classified. We report two cases of peripheral bronchial atresia diagnosed by prenatal ultrasonography (US) and magnetic resonance imaging (MRI). Evaluating an enlarged lung mass that is homogeneously hyperechoic on US and hyperintense on T2-weighted MRI can help in determining whether bronchial atresia is present. Proximal type is suggested when a dilated main bronchus is observed as a tubule structure of an involved lung hilum. In our cases, T2-weighted MRI revealed homogeneously hyperintense lung lesion with decreased signal intensity of adjacent lobe, flattening diaphragm, and mediastinal shift. Dilatation of the main bronchus was not observed and the opposite lung was normal in appearance. These findings were explained by secondary compression due to enlargement of the involved lung. The preservation of vascular structure and the retained normal shape, though enlarged, in the affected lobe were observed, which demonstrated undisrupted pulmonary architecture of the lobe. Thus, congenital cystic adenomatoid malformation was excluded because pulmonary architecture was relatively preserved. Finally, presumed diagnoses of the peripheral bronchial atresia were made and confirmed by postnatal chest computed tomography.

Prenatal and postnatal management of congenital bronchial atresia (CBA): single tertiary center report

OBJECTIVE

To summarize our diagnosis and management experience of congenital bronchial atresia (CBA).

METHODS

A retrospective review was conducted, clinical data were collected of all patients with CBA.

RESULTS

Among the nine patients (5 males and 4 females), six cases with right side and three cases with left cases, including one patient with mainstem bronchial atresia (MBA), two cases with lobar bronchial atresia (LBA), six cases with segmental bronchial atresia (SBA). Eight were diagnosed as congenital cystic adenomatoid malformation (CCAM) type III by ultrasound (US) in prenatal. The MBA patient was diagnosed by computed tomography (CT) and bronchofibroscopy, only two patients by pathological findings and the other six patients by CT. Five cases were accompanied by CCAM, one case with bronchopulmonary sequestration (BPS), two cases with emphysema. Eight cases except MBA were underwent thoracoscopic surgery treatment and had favorable prognosis. Two cases with LBA merged with complication of pectus excavatum after surgery. One case with MBA had no surgery and died in the 13 days old.

CONCLUSIONS

CBA is an easily misdiagnosed disease from pathologic conditions, definitive diagnosis of this condition depends on combination CT or clinical pathologic diagnosis. Thoracoscopic resection is a safe and feasible treatment of CBA in experienced hands.

Imaging findings of bronchial atresia in fetuses, neonates and infants

Congenital lung malformations are increasingly detected before birth. However, bronchial atresia is rarely identified in utero and not always recognized in neonates. There are two types of atresia: 1) proximal, located at the level of the mainstem or the proximal lobar bronchi, which is extremely rare and usually lethal during pregnancy, causing a tremendous volume increase of the distal involved lung with secondary hypoplasia of the normal lung, and 2) peripheral, located at the segmental/subsegmental bronchial level, which may present as an isolated lesion or as part of a complex congenital malformation. Prenatal findings are mostly nonspecific. Postnatal exams show overinflated lung areas and focal bronchial dilations. The typical fluid-filled bronchoceles are not always observed in neonates but develop progressively in the first months of life. This pictorial essay describes the spectrum of imaging findings of bronchial atresia in fetuses, neonates and infants.