with low morbidity and mortality; thoracoscopic resection is feasible for some lesions, with the remainder approached via traditional thoracotomy Bronchogenic Cyst Bronchogenic cysts are believed to result from aberrant budding from the primitive foregut or tracheobronchial tree They arise from the trachea or a bronchus and may be found anywhere along the tracheobroncheal tree, in the lung substance, adjacent to the esophagus or in other ectopic locations Clinical Recognition Centrally located cysts may present with symptoms caused by compression of an airway or the esophagus Wheezing, persistent cough, fever, recurrent pneumonia, and dysphagia may result in such children In infants and smaller children, large airway compression can lead to significant and life-threatening air trapping and CLE In contrast, patients with peripherally located cysts are more likely to be asymptomatic or present with milder, nonspecific symptoms, such as cough, dyspnea, tachypnea, or wheezing Physical examination is often unrevealing, but in patients with large, centrally located lesions, tracheal deviation may be present Management Initial detection of bronchogenic cysts almost always occurs by radiograph Chest radiograph may demonstrate findings of a smooth paratracheal or hilar mass, airway displacement and/or air trapping, or a structure containing an air–fluid level if there is communication with the airway or gastrointestinal tract (Fig 124.8 ) CT scan and MRI are helpful in identifying and delineating the anatomic relations of these lesions to surrounding structures Cysts with turbid, mucoid fluid may appear solid on CT scan The standard treatment of bronchogenic cysts is surgical resection, even if asymptomatic Active infection, if present, should be brought under control before resection Typically, this is done in the inpatient setting with intravenous antibiotics and close observation Asymptomatic cysts should be removed to establish the diagnosis and to prevent the complications of secondary bronchial communication, bleeding, or perforation into the pleural cavity Carcinomas and fibrosarcomas have been reported to arise in benign-appearing bronchogenic cysts Preservation of adjacent normal lung parenchyma is ideal, but some lesions require concomitant wedge, segmental, or lobar lung resection Thoracoscopy may be used for some lesions, depending on their location and size FIGURE 124.8 A: Plain film of a patient with a bronchogenic cyst arising from the right main stem bronchus B: Computed tomographic scan of a similar lesion reveals large fluid-filled cyst compressing adjacent lung tissue Congenital Lobar Emphysema Congenital lobar emphysema (CLE), also known as congenital lobar hyperinflation (CLH), is caused by overexpansion of the air spaces of a segment or lobe of histologically normal lung (Fig 124.9 ) Operative findings can reveal large blebs protruding from the lung parenchyma (Fig 124.10 ), but often the lobe is anatomically normal in appearance, with the exception of massive overdistention Compression of adjacent normal lung and mediastinal structures frequently occurs, which can result in impairment of gas exchange and lifethreatening circulatory collapse This process is caused by air trapping from either a developmental deficiency of supporting cartilage in the bronchus of a particular lobe or a partially obstructing bronchial lesion, either endobronchial or from external compression (as with a bronchogenic cyst) FIGURE 124.9 Congenital lobar emphysema of the left upper lobe in a 3-month-old girl who presented with decreased breath sounds and rales in this area Note the left-sided secondary compression atelectasis of the lower lobe Clinical Recognition Infants with CLE are often normal in appearance at birth, but develop tachypnea, cough, wheezing, dyspnea, and/or cyanosis within a few days The onset of symptoms may be more gradual; nevertheless, 80% of patients are symptomatic by months of age The upper lobes are involved in about two-thirds of patients Chest radiographs show striking radiolucency in the involved lobe with mediastinal shift to the opposite side The diaphragm is usually flattened on the affected side It can be difficult to tell whether pulmonary markings are present in the involved lobe, and pneumothorax may be suspected The compressed normal lung may be erroneously believed to be atelectatic with the emphysematous lobe compensatory Management Initially, the clinical presentation and physiologic derangements may be similar to that of tension pneumothorax, and the two entities should be distinguished Physical examination may reveal an asymmetric thorax, unilateral hyperresonance and decreased breath sounds on the affected side, and evidence of mediastinal shift Typical findings on chest radiograph include lobar overinflation, contralateral shift of the mediastinum, and collapse of lung tissue on the contralateral side, with flattening of the ipsilateral hemidiaphragm ( Fig 124.9 ) In a stable patient, CT or ventilation/perfusion scanning can be helpful in establishing the diagnosis FIGURE 124.10 Operative findings in a child with congenital lobar emphysema