68 - Malignant Pleural Effusions

Editors: Shields, Thomas W.; LoCicero, Joseph; Ponn, Ronald B.; Rusch, Valerie W.

Title: General Thoracic Surgery, 6th Edition

Copyright 2005 Lippincott Williams & Wilkins

> Table of Contents > Volume I - The Lung, Pleura, Diaphragm, and Chest Wall > Section XIV - Congenital, Structural, and Inflammatory Diseases of the Lung > Chapter 80 - Congenital Lesions of the Lung

Chapter 80

Congenital Lesions of the Lung

Marleta Reynolds

Most congenital lesions of the lung are recognized when respiratory symptoms develop in the newborn or infant. An increasing number are being diagnosed prenatally. Some are identified in the asymptomatic child on an incidental radiograph of the chest. The remainder are diagnosed in the older child during evaluation for a respiratory infection. In an infant with severe respiratory distress, knowledge of the pathology and the ability to make a quick and accurate diagnosis based on a radiograph of the chest may be critical. Ultrasonography and computed tomographic (CT) scanning allow greater diagnostic accuracy when time permits.

TRACHEAL AGENESIS AND ATRESIA

Tracheal agenesis or atresia leads to respiratory distress at birth and is usually fatal. Floyd and colleagues (1962) categorized the anomalies into three subtypes. Type I (10%) includes partial atresia of the trachea with a normal short segment of distal trachea arising from the anterior esophageal wall. Type II (59%) is complete tracheal agenesis with normal bronchi, bifurcation, and carina, with the carina connecting to the esophagus. Type III (31%) is complete agenesis of the trachea, with the bronchi arising from the esophagus. Affected babies may be premature, and maternal polyhydramnios is often associated. At birth, the babies turn blue and do not have an audible cry. An endotracheal tube cannot pass beyond the vocal cords, but esophageal intubation may temporarily improve ventilation. Associated anomalies are present in 84% and include other bronchopulmonary malformations, cardiac defects, vertebral anomalies, and gastrointestinal anomalies, as reported by Manschot and associates (1994). Although Kerschner and Klotch (1997) reported no long-term survivors from attempts at reconstruction, Hiyama and colleagues (1994) described a baby with tracheal atresia who was successfully managed with multiple surgical procedures. The first procedure for the type II lesion included banding of the distal esophagus and gastrostomy. An endotracheal tube was then passed into the esophagus to just above the bronchoesophageal fistula. After 9 months of mechanical ventilation and gastrostomy feedings, a tracheostomy was created into the upper trachea. The esophagus was disconnected from the trachea and later reconstructed with a colon interposition. At the time of the report, the child was 4 years old.

BRONCHIAL ANOMALIES

Abnormal bronchial development may result in complete bronchial atresia, an aberrant origin of a main-stem or segmental bronchus from the trachea, or the abnormal communication of the bronchus with another foregut derivative. Structural abnormalities of a bronchus may lead to lobar emphysema (Fig. 80-1).

Tracheal Diverticulum and Bronchus

A tracheal diverticulum may arise from the cervical or thoracic portion of the trachea and ends blindly or in a rudimentary lung. Early and Bothwell (2002) reported two infants in whom a tracheal diverticulum was discovered on bronchoscopy. Computed tomography in conjunction with bronchoscopy can correctly identify the lesion. Surgical resection is reserved for those in whom the diverticulum is large enough to cause compression of adjacent structures or becomes a source of continued pulmonary sepsis.

If the bronchial structure connects to a normal segment or lobe of lung, it is referred to as a tracheal bronchus. The accessory lung has normal pulmonary arterial and venous supply. Symptoms may result from stenosis of the tracheal bronchus or from other associated pulmonary anomalies. A radiograph of the chest obtained because of recurrent pneumonia, stridor, or newborn respiratory distress reveals the portion of lung involved (Fig. 80-2). At bronchoscopy, the tracheal bronchus can be seen, and an assessment of the entire tracheobronchial tree should be performed. Conventional CT and high-resolution CT scanning can be used to demonstrate a tracheal bronchus. Wong and colleagues (1998) recommend serial coronal CT scans to better demonstrate

P.1102


a tracheal bronchus. Bronchography is seldom needed. Surgical resection of the tracheal bronchus and adjoining lung tissue is necessary only when it is clinically indicated (Fig. 80-3). McLaughlin and colleagues (1985) recorded 18 children with tracheal bronchi who presented with recurrent pneumonia and other respiratory symptoms. Bronchography revealed bronchial stenosis and bronchiectasis of the involved lung segment in 5 of the children. Their symptoms were relieved by resection. Vevecka and colleagues (1995) reported a 1-year-old child who was found to have a cystic adenomatoid malformation connecting to a tracheal bronchus.

Fig. 80-1. Bronchial anomalies resulting from abnormal bronchial development. Symptoms result from bronchial obstruction and pulmonary infection. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

Fig. 80-2. Incidental tracheal bronchus. The patient, a 3-year-old with a history of wheezing, also had an obstructed left upper lobe apical bronchus and emphysema of the left upper lobe. Left upper lobectomy was curative. From Congenital malformations of the lung. In Raffensperger JG (ed): Swenson's Pediatric Surgery. 4th Ed. Norwalk, CT: Appleton-Century-Crofts, 1980, p. 700. With permission.

Fig. 80-3. Bilateral tracheal bronchi in a child being evaluated for chronic cough. Conservative treatment was recommended. From Holinger PH: Abnormalities of the larynx and tracheobronchial tree. In Swenson O (ed): Swenson's Pediatric Surgery. 3rd Ed. Norwalk, CT: Appleton-Century-Crofts, 1969, p. 297. With permission.

Bronchial Atresia

An atretic bronchus ends blindly in lung tissue. At birth, the portion of lung adjacent to the atretic bronchus is filled with fluid. The fluid is soon reabsorbed and replaced by air from the adjacent lung tissue through the pores of Kohn. Eventually, retained secretions result in a mucocele. Compression of adjacent normal bronchial structures leads to emphysematous change in the lung. Symptoms of wheezing and stridor may develop, and there is a significant risk for pulmonary infection. A radiograph of the chest shows a hilar mass with radiating solid channels surrounded by hyperaerated lung. CT scanning can differentiate the centrally placed cystic mucocele characteristic of bronchial atresia from a bronchogenic cyst or lobar emphysema. Resection is indicated to prevent pulmonary sepsis. For nine years, Haller and colleagues (1980)

P.1103


observed a child with mild symptoms who had bronchial atresia and associated lobar emphysema. Progressive respiratory symptoms eventually prompted resection of the involved segment. The report documents the natural history of the lesion and further supports timely resection. Kuhn and Kuhn (1992) described the fourth reported case of an infant with bronchial atresia and bronchogenic cyst. Van Klaveren and associates (1992) reported two patients with bronchial atresia and pectus excavatum.

Anomalous Bronchi

The most common communication between the trachea or bronchus and another foregut derivative is a tracheoesophageal fistula. Other anomalous connections are rare. Since 1950, Gans and Potts (1951) and Nikaido and Swenson (1971) have reported three infants from my institution who had an esophageal bronchus. All presented with respiratory distress and pneumonia and were found by esophagogram to have a portion of lung communicating with the esophagus through a bronchial structure.

Fig. 80-4. A. Atretic right bronchus in a 1-month-old girl who presented with respiratory distress, cough, and fever. B. The esophagogram outlines the right bronchus and lung. C. At surgery, the right esophageal bronchus is identified. A right pneumonectomy was performed. She has had significant morbidity in the 4 years postoperatively. From Congenital malformations of the lung. In Raffensperger JG (ed): Swenson's Pediatric Surgery. 4th Ed. Norwalk, CT: Appleton-Century-Crofts, 1980, p. 700. With permission.

The anomalous origin of a lobar or segmental bronchus from the esophagus (esophageal bronchus) may be right or left sided and may involve the upper or lower lobes. The vascular supply to the involved lobe varies; some lobes have a normal pulmonary vascular pattern and others a systemic supply. Extralobar and intralobar sequestrations (identified by the anomalous blood supply and absence of bronchial communication) occasionally communicate with the esophagus or other foregut derivatives. Confusion over terminology has prompted some researchers to refer to all these anomalies as congenital bronchopulmonary foregut malformations.

Persistent or recurrent pneumonia in an infant or child may be caused by bronchial communication with the esophagus. An esophagogram outlines the esophageal bronchus (Fig. 80-4). Resection of the chronically infected portion of the lung is indicated. Lallemand and associates (1996) reported three cases of esophageal bronchi. In two cases, the anomalous bronchus was a main-stem bronchus. These two

P.1104


patients were treated by implantation of the anomalous bronchus into the trachea.

Bronchial Stenosis

A true congenital bronchial stenosis is rare. Bronchial stenosis is seen most often in the right main-stem bronchus secondary to inflammatory changes after improper and frequent suctioning of an infant on prolonged ventilatory support. Granulation tissue builds up at the main-stem orifice. The lung distal to the obstruction becomes chronically infected or emphysematous (Fig. 80-5). Repeated bronchial dilations may be necessary to restore normal lung function and treat the infection. Jaffe (1997) reported successful balloon dilation in four of six patients with congenital and acquired tracheal and bronchial stenosis. Bronchoplastic procedures may reduce the need for pulmonary resection when the chronic infection does not resolve after attempts at bronchial dilation.

Tracheobiliary and Bronchobiliary Fistula

Only 20 cases of tracheobiliary and bronchobiliary fistula have been reported. Affected infants present with mild or severe respiratory distress and may have bile-stained secretions. Recurrent pneumonias may prompt a chest radiograph. Bronchoscopy and fistulography are diagnostic. Egrari and associates (1996) used a hepatoiminodiacetic acid scan to demonstrate the anomaly in an affected infant. The fistula usually joins the right main-stem bronchus near the carina. Division of the fistula is usually curative. Ferkol and colleagues (1994) described an infant with bronchobiliary fistula. The biliary drainage of the left lobe liver was through the fistulous tract in this patient. Division of the fistula was followed several days later by resection of the fistulous tract and the abnormal left lobe of the liver because of biliary sepsis. In the review of the malformation by Tommasoni and associates (2000), the fistulae were reported to have arisen from the carina in 55%, the right main-stem bronchus in 30%, the left bronchus in 10%, and was not identified in 5%.

Fig. 80-5. Recurrent right upper lobe and entire right lung atelectasis in an infant with hyaline membrane disease who required prolonged intubation and ventilation. The right main-stem bronchus was stenotic. Repeated dilations were palliative. This computed tomographic scan was obtained to clarify distal anatomy or identify other pathologic change. Note two areas of significant stenosis in the right main stem bronchus.

The fistulae end in the left hepatic biliary ductal system. Associated biliary anomalies are present in 56%. Identification of a normal biliary tree and continuity with the duodenum is mandatory. The fistula may provide a substantial portion of the biliary drainage of the liver and a fistula-enteric anastomosis may need to be constructed.

CONGENITAL LOBAR EMPHYSEMA

Congenital lobar emphysema refers to the isolated hyperinflation of a lobe in the absence of extrinsic bronchial obstruction. The left upper lobe is involved most often, followed in incidence by involvement of the right middle lobe. Boland and colleagues (1956) found hypoplastic cartilage in the bronchus of two of seven patients with lobar emphysema. Lincoln and associates (1971) described hypoplastic or absent cartilage in 22 of 28 examples reviewed. A series collected by Scarpelli and Auld (1978) reported a 25% incidence of dysplasia of the bronchial cartilage. Stovin (1959) reported abnormal orientation and distribution of the bronchial cartilage in his series of patients.

A subset of lobar emphysema is the polyalveolar lobe, first described by Hislop and Reid (1970). In an infant with classic congenital lobar emphysema, they found an increase in the number of alveoli in the affected lobe. A subsequent report by Tapper and associates (1980) reevaluated a group of infants with congenital lobar emphysema and found that 6 of 16 had the abnormal characteristics of the polyalveolar lobe.

Lobar emphysema produces symptoms in infancy. Often, a history of tachypnea, retraction of the chest wall, and wheezing since birth exists. An upper respiratory infection may complicate the condition and precipitate severe respiratory distress. Most children with lobar emphysema present before 6 months of age. Some infants develop symptoms in the first few days of life and require urgent intervention. Physical examination reveals a shift of the trachea and mediastinum to the contralateral hemithorax. Breath sounds are decreased on the affected side, with associated hyperresonance. Radiographs of the chest show hyperaeration of the affected lobe with atelectasis of the adjacent lobes and a mediastinal shift (Fig. 80-6). Careful inspection of vascular markings reduces the risk for misdiagnosis of this lesion as a tension pneumothorax.

In a newborn with severe respiratory distress, a radiograph of the chest is the only preoperative study that is indicated. In an infant with mild to moderate respiratory distress, CT scanning can establish the diagnosis of congenital

P.1105


lobar emphysema by showing the hyperlucent expanded lobe and stretched, attenuated vessels. CT scanning can also exclude extrinsic causes of lobar emphysema, such as vascular anomalies or a mediastinal mass. In selected patients, Markowitz and colleagues (1989) recommend a radionuclide ventilation-perfusion scan to confirm the absent function of the involved lobe. Stigers (1992) and Doull (1996) and their associates recommend bronchoscopy to exclude intraluminal pathology and to assess the extent of bronchial collapse during ventilation.

Fig. 80-6. Radiograph of a newborn with lobar emphysema involving the right middle lobe. Note the compressed right lower lobe and mediastinal shift.

Any infant with moderate to severe respiratory symptoms and a diagnosis of congenital lobar emphysema should be treated with lobectomy. Infants with mild symptoms may be carefully followed, although this management strategy is controversial. At operation, the chest is opened as soon as possible after induction of anesthesia. Positive-pressure ventilation causes further overinflation of the involved lobe and increases the risk for cardiovascular compromise. Gupta and associates (1998) recommend selective intubation of the contralateral lung with controlled ventilation in these infants. Raghavendran and associates (2001) recommend continuous caudal epidural anesthesia to avoid the risk for positive pressure ventilation. The abnormal lobe usually herniates through the thoracotomy incision. The lobe feels like sponge rubber, does not deflate, and bounces back into shape after it is compressed. Its edges are rounded and poorly defined. The remaining lung is atelectatic. Before resection, the mediastinum must be carefully examined for lesions that could have obstructed the bronchus. After lobectomy, the remaining lung expands to fill the chest. The emphysematous lobe characteristically does not deflate, even after it is removed from the chest.

Infants with hyaline membrane disease who require prolonged mechanical ventilation may develop acquired lobar emphysema (Fig. 80-7). The right lower lobe is most frequently affected. Suction trauma may cause squamous metaplasia of the bronchial orifice, and repeated barotrauma contributes to the ruptured alveoli and emphysematous changes. Radionuclide scans demonstrate poor perfusion of the affected lobe. Cooney and colleagues (1977) recommended lobectomy when the infant cannot be weaned from the ventilator because of the acquired emphysematous lobe.

Fig. 80-7. A. Radiograph of the chest of a 2-month-old infant with bronchopulmonary dysplasia. B. Within 3 months, lobar emphysema developed in his right lower lobe. Further mediastinal shift and increasing ventilator requirements prompted lobectomy.

In older infants with a history of respiratory problems, CT may help identify other causes of acquired lobar emphysema, such as extrinsic bronchial compression from enlarged lymph nodes, a bronchogenic cyst, or anomalous blood vessels. In an older child with an acute onset of symptoms, bronchoscopy is indicated to rule out an aspirated foreign body or an endobronchial mass. The bronchoscopy should be planned to immediately precede thoracotomy. Oxygen, antibiotics, and humidity are administered prophylactically.

P.1106


PULMONARY DYSPLASIA

Pulmonary Agenesis and Aplasia

Unilateral pulmonary agenesis results from lack of development of a single lung bud. Lung parenchyma and pulmonary vessels are lacking. Sbokos and McMillan (1977) reported a 50% incidence of associated cardiac disease, especially when the agenesis was on the right side. Say and associates (1980) noted that pulmonary agenesis may be associated with a chromosomal abnormality (46,XX,2p+).

A newborn with unilateral pulmonary agenesis may be asymptomatic or present with tachypnea, dyspnea, and cyanosis. Older infants or children may present with wheezing that suggests asthma or bronchitis. On physical examination, the trachea and mediastinal structures are shifted to the involved side. The overall shape of the chest is normal. Signs of airway obstruction and poor bronchial drainage may be recognizable. A radiograph of the chest reveals absence of lung markings and mediastinal shift to the ipsilateral side (Fig. 80-8). The differential diagnosis includes total lung atelectasis, total lung sequestration, or lung with an esophageal bronchus. The normal position of the diaphragm and normal intercostal spaces precludes atelectasis. An esophagogram and CT scan exclude the other possibilities. Echocardiography helps in diagnosing the associated cardiac lesions. No particular treatment exists for pulmonary agenesis, but correction of the cardiac anomaly may relieve some of the symptoms. Massumi and associates (1966) reported that 30% of infants with agenesis die in the first year of life, and 50% die within the first 5 years. The mortality rate was higher with right-sided agenesis. Maltz and Nadas (1968) reviewed the world literature and found 164 cases of pulmonary agenesis. Of the 36 patients reported by 1954, 24 were alive in 1968.

Bilateral pulmonary agenesis is incompatible with life, although Claireaux and Ferreira (1958) reported one infant who survived for 15 minutes. The trachea ends blindly or into primitive lung tissue. The incidence of associated anomalies is high.

Fig. 80-8. Radiograph of the chest of a newborn with respiratory distress and agenesis of the right lung. Marked mediastinal shift to the ipsilateral side exists.

Pulmonary aplasia is similar to pulmonary agenesis in that pulmonary parenchyma and vessels are absent. The blind bronchial stump may serve as a source of repeated infection in the normal contralateral lung. The stump may be identified by bronchoscopy or CT scan. Once recognized, the chronically infected stump should be resected (Fig. 80-9).

Primary Pulmonary Hypoplasia

Pulmonary hypoplasia can be identified pathologically by the radial alveolar count and the ratio of lung weight to body weight. Pulmonary hypoplasia is primary if no obvious cause for the hypoplasia can be found. Swischuk and associates (1979) reported that four of eight infants with primary pulmonary hypoplasia had mean radial alveolar counts lower than normal and thickening of the pulmonary arteriolar wall. The hypertrophy of the muscular layer of the pulmonary arteriole develops in response to fetal stress. This hypertrophy is frequently found in infants with pulmonary hypoplasia and other causes of pulmonary hypertension.

P.1107


Haworth (1981) suggested that the normal postnatal regression of the pulmonary arteriolar muscle does not occur.

Fig. 80-9. The blind bronchial stump of pulmonary aplasia. Retained secretions in the stump led to recurrent pulmonary infections. In this setting, bronchography has been replaced by computed tomography and bronchoscopy. From Holinger PH: Abnormalities of the larynx and tracheobronchial tree. In Swenson O (ed): Swenson's Pediatric Surgery. 3rd Ed. Norwalk, CT: Appleton-Century-Crofts, 1969, p. 298. With permission.

Primary pulmonary hypoplasia produces symptoms immediately after birth. An infant develops severe respiratory distress that is often unresponsive to supplemental oxygen. A radiograph of the chest demonstrates small lungs and the absence of other causes for respiratory distress. The thickened pulmonary arterioles predispose the infant to an exaggerated response to hypoxemia, acidosis, and hypercarbia. Therapy is aimed at lowering the pulmonary vascular resistance and preventing the inevitable persistent fetal circulation. Right-to-left shunting of blood occurs at three levels: across the patent foramen ovale, across the patent ductus arteriosus, and within the pulmonary capillary bed. Six of the eight infants reported by Swischuk and associates (1979) died despite aggressive management.

Secondary Pulmonary Hypoplasia

Secondary pulmonary hypoplasia is associated with various fetal and maternal abnormalities (Table 80-1). One of the most common is Potter's syndrome, in which bilateral renal agenesis results in oligohydramnios and compression of the developing fetus by the uterus. The fetus's face is distorted, and the chest is bell-shaped. Lung volume is small, with a decrease in the number of airway generations and alveoli (Fig. 80-10). The alveoli and pulmonary arterioles are smaller than normal. Other conditions that result in oligohydramnios (e.g., amniotic fluid leaks and renal dysplasias) are also associated with secondary pulmonary hypoplasia.

Table 80-1. Conditions Associated with Secondary Pulmonary Hypoplasia

Oligohydramnios
   Potter's syndrome (bilateral renal agenesis)
   Renal dysplasias
   Amniotic fluid leak
Bone dysplasias with a small or rigid chest wall
   Achondroplasia
   Chondrodystrophia fetalis calcificans
   Spondyloepiphyseal dysplasia
   Osteogenesis imperfecta
   Thanatophoric dwarfism
   Neonatal hypophosphatemia
Decreased fetal respiratory movements
   Congenital arthrogryposis multiplex congenita
   Camptodactyly and multiple ankylosis syndrome
   Congenital myotonic dystrophy
   Asphyxiating thoracic dystrophy
Diaphragmatic elevation
   Membranous diaphragm
   Abdominal mass or ascites
   Phrenic nerve agenesis
Intrathoracic space-occupying lesions
   Congenital diaphragmatic hernia
   Congenital cystic adenomatoid malformation
   Mediastinal neoplasms and cystic hygroma
   Enteric cysts (esophageal duplication)
Pulmonary vascular anomalies
   Pulmonary artery agenesis
   Scimitar syndrome
Miscellaneous
   Omphalocele
   Down's syndrome
   Rhesus isoimmunization of the fetus
From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

Neurologic or musculoskeletal conditions that depress fetal respiratory movements are associated with hypoplastic lungs. Vilos and associates (1984) observed the fetus of a woman with myotonic dystrophy using ultrasonography; the fetus had no respiratory movements, and the lungs were hypoplastic at birth. Wigglesworth and Desai (1979) reported that in experimental animals, the in utero transection of the spinal cord and the resulting inability of the animal to make respiratory movements result in significant pulmonary hypoplasia.

Infants who have congenital bony dysplasias may also have small and rigid chests and associated hypoplastic lungs; thanatophoric dwarfism is a good example. Most of these infants die from respiratory problems (Fig. 80-11). Jeune's syndrome, a familial chondrodystrophy, is also called asphyxiating thoracic dystrophy. These infants' chests are small and rigid and the lungs hypoplastic (Fig. 80-12). Futile attempts at chest reconstruction have been made, but survival has not been reported.

The developing lungs can also be affected by the abnormal development or function of the diaphragm. Phrenic nerve agenesis results in poor diaphragmatic muscle development and pulmonary hypoplasia. Infants with large abdominal masses or ascites have restricted lung development because of the elevation of the diaphragm. Hershenson and associates (1985) evaluated chest size in infants with giant omphaloceles and found them significantly decreased compared

P.1108


with controls. Many of the infants in their series had prolonged respiratory insufficiency, and autopsy study of one infant confirmed the presence of pulmonary hypoplasia.

Fig. 80-10. Potter's syndrome with secondary pulmonary hypoplasia. The chest is bell shaped. Chest tubes were inserted to manage pneumothoraces resulting from barotrauma. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

Fig. 80-11. Thanatophoric dwarf. Normal lung development is restricted by the size of the chest. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

Fig. 80-12. Jeune's syndrome or asphyxiating thoracic dystrophy. The size and shape of the chest precludes normal lung development. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

The most common cause of secondary pulmonary hypoplasia is a congenital diaphragmatic hernia (see Chapter 51). The herniated viscera physically restrict lung growth on the ipsilateral side. In addition, shift of mediastinal structures results in contralateral pulmonary hypoplasia (Fig. 80-13). Kitagawa and associates (1971) reported that the lungs of infants with congenital diaphragmatic hernia had fewer airway generations, alveoli, and pulmonary arterioles than normal. Clinical correlation with the autopsy findings demonstrates that the most severe respiratory failure was present in infants in whom the muscularization of the pulmonary arterioles extended out from the preacinar arterioles into the interacinar arterioles. The high mortality rate associated with congenital diaphragmatic hernia is directly related to the pulmonary hypoplasia. High pulmonary vascular resistance and persistent fetal circulation are treated with high-frequency ventilation, 100% oxygen, sedation, alkalinization, and vasodilators. Extracorporeal membrane oxygenation has been used successfully to save 70% of infants with congenital diaphragmatic hernia who would otherwise have died from respiratory failure.

Some cases of secondary pulmonary hypoplasia cannot be readily explained. For instance, Cooney and Thurlbeck (1982) reported that Down's syndrome is associated with pulmonary hypoplasia. The autopsy study of seven children with Down's syndrome revealed hypoplastic lungs in six, without evidence of congenital heart disease or other pulmonary anomalies. Chamberlain and colleagues (1977) found that infants with rhesus isoimmunization have associated pulmonary hypoplasia. Respiratory insufficiency is a frequent cause of death in these infants. The etiology and pathophysiology of the associated pulmonary hypoplasia are unknown.

SEQUESTRATION

Pulmonary sequestration describes a segment or lobe of lung tissue that has no bronchial communication with the normal tracheobronchial tree. The arterial blood supply is from a systemic vessel. The vessel often arises from the abdominal aorta, travels upward, and penetrates the diaphragm to supply the sequestration. The venous return is usually through the pulmonary veins but may be to the systemic venous system. An extralobar sequestration is separate from the normal lung and has its own visceral pleura. An intralobar sequestration is situated within normal lung parenchyma (Fig. 80-14). A sequestration probably arises from a lung bud that is pinched off from the caudal foregut with its own blood supply. Boyden (1958) proposed this theory after reviewing data collected from embryos. Further study by Iwai and associates (1973) corroborated these findings.

Fig. 80-13. Congenital diaphragmatic hernia. A. The left side of the chest is filled with intestines, and the mediastinum is shifted to the contralateral side. The abdomen lacks normal intestinal gas pattern. B. After surgical repair of the hernia, the severely hypoplastic ipsilateral lung is identified. The contralateral lung is also hypoplastic. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

P.1109


Antenatal diagnosis of a sequestration can be made between 16 and 24 weeks' gestation by ultrasonography. Sakala and associates (1994) reviewed the literature and reported a boy:girl ratio of 3:1. In half of the cases, mediastinal shift, polyhydramnios, and hydropic changes were found. All fetal deaths in this group of 11 cases occurred with hydropic changes. Sonographic differentiation of pulmonary sequestration and congenital cystic adenomatoid malformation (CCAM) may be difficult. Adzick and associates (1998) reported a large series of patients with extralobar sequestration diagnosed in utero. Of the 39 lesions followed during pregnancy, 28 regressed and completely or nearly completely disappeared. The lesion is identified on color flow Doppler ultrasonography as an echodense thoracic mass with arterial blood supply from the aorta. Postnatal chest radiography could not always identify the lesion, but CT scanning or magnetic resonance (MR) imaging was diagnostic. All of the infants in their series have been followed without invasive therapy. Hubbard and Crombleholme (1998) and Becmeur and colleagues (1998) suggest that early delivery may be indicated if hydropic changes develop. Fetal intervention for drainage of polyhydramnios or thoracoamniotic shunting may also be considered.

Fig. 80-14. Pulmonary sequestrations may be intralobar or extralobar. No bronchial communications exist, and the arterial supply to the segment or lobe is systemic. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

Extralobar Sequestration

Twenty-five percent of sequestrations are extralobar. They are triangular, and they occur in the left chest 90% of the time. Usually found in the posterior costophrenic angle,

P.1110


they may also occur in the mediastinum or within or beneath the diaphragm in a periadrenal location. Some of the latter lesions may have a connection with the foregut. Diaphragmatic hernias are associated in 30%. Ultrasonography and CT scanning are useful screening examinations (Fig. 80-15). Color flow Doppler and MR imaging are superior to CT scanning in identifying the systemic arterial supply. In most infants and children with extralobar sequestration, the lesion is found on an incidental radiograph of the chest. Repeated infections in the lesion may develop if a communication with the foregut is present. Surgical resection is indicated for symptomatic patients and when the diagnosis is in question.

Intralobar Sequestration

Savic and associates (1979) reviewed a large series of sequestrations, and of 391 intralobar sequestrations, 164 were in the right lower lobe and 227 were in the left lower lobe. Only 9 instances of sequestration occurred in the upper or middle lobes. In 96% of the sequestrations in this series, the venous return was to the pulmonary venous system.

Communication through the pores of Kohn may lead to chronic infection in the sequestered lobe. Children and young adults with recurrent left lower lobe pneumonia should be suspected of having an intralobar sequestration (Fig. 80-16). Infection can also lead to abscess formation and further cloud the diagnostic picture. In some children and adults, degenerative arteriosclerotic changes in the systemic artery supplying the sequestration may lead to hemoptysis. One of my patients presented with hemoptysis and an expanding lung mass. The systemic artery leading to the sequestration had become atherosclerotic and developed

P.1111


a false aneurysm within the sequestered lobe (Fig. 80-17). Rubin and colleagues (1994) reported fatal hemoptysis in a young adult diagnosed in infancy with an intralobar sequestration. An aneurysm of the anomalous vessel had ruptured into the tracheobronchial tree. In the newborn, high flow through the systemic artery with normal pulmonary venous return may result in congestive heart failure.

Fig. 80-15. A. Abnormal radiograph of the chest of a newborn with respiratory distress. B. Ultrasound identified the anomalous vessel coursing through the diaphragm and entering the sequestration. C. This computed tomographic scan clearly demonstrates the anomalous artery arising from the thoracic aorta and entering the sequestered lung.

Fig. 80-16. A recurrent left lower pneumonia should suggest the possibility of an intralobar sequestration. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

Fig. 80-17. A. This boy had had repeated left lower lobe pneumonia and presented at age 12 years with hemoptysis and a consolidated left lower lobe. B. Rupture of the sequestration produced a massive hemothorax and shock. Emergency left lower lobectomy was performed. C. The pathologic specimen reveals an aneurysm of the atherosclerotic vessel arising from the aorta. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

Diagnosis in the newborn can be made with chest radiography and color flow Doppler ultrasonography. In the older child, CT scanning can be diagnostic, although MR imaging can better demonstrate the vascular supply. Angiography is seldom indicated (Fig. 80-18).

Treatment consists of a lobectomy. Careful identification of the arterial supply and suture ligation is necessary. Nuchtern and Harberg (1994) reported on six patients with intralobar sequestration who all required lobectomy. There was no mortality and minimal morbidity in their group of patients. Harris and Lewis (1940) reported an attempted lobectomy in a 5-year-old; it ended in exsanguinating hemorrhage when the systemic arterial supply was not recognized and was divided before control was obtained. The venous return must also be identified before resection. Thilenius (1983) and Alivizatos (1985) and their colleagues reported pulmonary infarction after inadvertent ligation of the total venous return of the right lung during resection of right lower lobe sequestration. Shermeta (personal communication, 1985) identified a similar anomaly and successfully reanastomosed the pulmonary veins of the upper and middle lobe to the left atrium. Anomalous venous drainage of a single lobe or lobes of the right lung to the inferior vena cava below the diaphragm or to the right atrium is referred to as scimitar syndrome. This anomaly is discussed in Chapter 82.

PARENCHYMAL PULMONARY LESIONS

Congenital parenchymal pulmonary lesions include isolated cystic lesions and diffuse cystic disease. Primary lymphangiectasia usually presents as bilateral diffuse cystic

P.1112


disease in infancy and is fatal. Unilateral intrapulmonary lymphangioma is rare and difficult to differentiate from cystic adenomatoid malformation. Kim and associates (1995) reported the high-resolution CT findings. Thickened bronchovascular bundles and interlobular septa correlated with dilated lymphatics on pathologic examination. The infant they described was successfully treated with pneumonectomy. Other diffuse cystic disease is associated with various syndromes or diseases (e.g., Marfan's syndrome, interstitial fibrosis, histiocytosis, and Ehlers-Danlos syndrome). Surgical therapy is not indicated.

Fig. 80-18. This aortogram demonstrates the systemic arterial supply of an intralobar sequestration. Angiography is indicated if computed tomography does not accurately identify the lesion or if concomitant congenital heart disease is suspected. From Congenital malformations of the lung. In Raffensperger JG (ed): Swenson's Pediatric Surgery. 4th Ed. Norwalk, CT: Appleton-Century-Crofts, 1980, p. 703. With permission.

Fig. 80-19. Bronchogenic cysts are formed by abnormal budding of the respiratory tract and may be found in a variety of locations. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

An isolated cystic lesion may be congenital or acquired, and differentiation between the two may be difficult. Careful review of all chest radiographs made since birth helps to make the differentiation. CT scanning is excellent for differentiating and identifying a bronchogenic cyst or congenital cystic adenomatoid malformation (CCAM) from an isolated pulmonary cyst.

BRONCHOGENIC CYSTS

Bronchogenic cysts can be found in the hilum of the lung, mediastinum, posterior sulcus, and pulmonary parenchyma (Fig. 80-19), as well as in uncommon extrathoracic locations (see Chapter 194). The cysts are lined with ciliated columnar or cuboidal epithelium on a fibromuscular base. Squamous

P.1113


metaplasia may replace the epithelial lining, and when secondarily infected, the epithelium may be destroyed. The cyst walls are thin and may contain cartilage and bronchial glands. The cysts are usually single but may be multilocular or multiple. The lower lobes have been reported as most commonly involved with parenchymal bronchogenic cysts. According to Ribet and colleagues (1996), however, of 21 cysts in infants and children, the right upper and left upper lobes were involved in seven cases each, the left lower lobe in six cases, and the right lower lobe in only one case. Parenchymal bronchogenic cysts frequently communicate with the tracheobronchial tree. Parenchymal cysts usually present with signs of pulmonary sepsis; however, approximately 20% of the infants and children are asymptomatic, according to Ribet and colleagues (1996). In four of their patients, the cyst was identified by antenatal ultrasonography.

Fig. 80-20. Radiographs of the chest demonstrate a bronchogenic cyst of the left upper lobe.

Fig. 80-21. An air fluid level in an infected bronchogenic cyst is seen in this radiograph. This 10-month-old girl presented with a 4-day history of fever and cough. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

Fig. 80-22. This intrapulmonary bronchogenic cyst resembles a solid pulmonary lesion. This 4-year-old patient presented with hemoptysis. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

Fig. 80-23. Mediastinal bronchogenic cyst. From Snyder M, et al: Diagnostic dilemmas of mediastinal cysts. J Pediatr Surg 20:812, 1985. With permission.

Fig. 80-24. Specimen removed from an infant with a cystic adenomatoid malformation. Microscopically, there was marked proliferation of terminal bronchioles, and cartilage was lacking.

Fig. 80-25. This solid type of cystic adenomatoid malformation was found at autopsy in an infant who died shortly after birth. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

An air-filled bronchogenic cyst on a chest radiograph is sharply defined and round (Fig. 80-20). The cyst can expand rapidly, and if it ruptures it may produce a tension pneumothorax. Needle aspiration may temporize, but prompt surgical resection is necessary.

A cystic lesion that communicates with the airways and contains secretions or pus has an air fluid level on a decubitus or upright chest radiograph (Fig. 80-21). The infected cyst is often associated with a surrounding pneumonia. Sometimes the infected cysts are difficult to differentiate from an empyema or solid pulmonary lesion (Fig. 80-22). A triangular shadow on the radiograph usually indicates an empyema. CT scanning may differentiate a solid from a cystic lesion (Fig. 80-23). At times, a bronchogenic cyst has a high Hounsfield number on CT, which makes it difficult to differentiate the lesion from a solid mass. Nakata and associates (1993), in their study of eight mediastinal bronchogenic cysts, reported that in such instances MR imaging may help to establish the cystic nature of the lesion by the presence of relatively high signal intensities on the T1weighted images and very high signal intensities on T2-weighted imaging.

Surgical resection is indicated for all bronchogenic cysts in infants and children. Parenchymal cysts require segmental or lobar resection. Morbidity and mortality should be near zero in these cases.

CONGENITAL CYSTIC ADENOMATOID MALFORMATION

A spectrum of cystic and solid lesions of the lung can be identified histologically as CCAMs. In all varieties, there is an overgrowth of terminal bronchiolar-type tubular structures

P.1114


P.1115


and a lack of mature alveoli (Fig. 80-24). Luck and associates (1986) summarized the histologic appearance of CCAMs as follows:

  • An adenomatoid increase of terminal respiratory bronchiole-like structures lined by ciliated columnar epithelium occurs. Interspersed cysts may resemble immature alveoli. The connective tissue stroma contains disorganized elastic tissue and smooth muscle.

  • The mucosa of cysts lined with bronchial-type epithelium may show polypoid overgrowth projecting into the lumen of the cysts.

  • Bronchial mucoserous glands and cartilaginous plates are absent throughout the cystic parenchyma.

  • Occasional groups of alveolar cysts may be lined with mucus-secreting cells that resemble intestinal mucosa and do not resemble normal bronchial cells.

Table 80-2. Classification of Congenital Cystic Adenomatoid Malformations

Balea Clinical Presentation Cystic Lesionb Intermediate Lesionb Solid (Adenomatoid) Lesionb
Age Term newborn or older Infant Stillborn or premature
Fetal anasarca or ascites
Maternal polyhydramnios None Occasional
Other anomalies Rare Rare Common
Gross appearance Cystic; sometimes solid areas Either or both Solid; sometimes cystic areas
Histopathology
   Bronchiolar proliferation
+ Varying degrees +++
   Alveolar appearance Mature; separating bronchiole-type cysts Immature
Mucoid epithelium or cartilage Occasional Occasional Common
Prognosis Good Good Poor
Stockerc Clinical Presentation Type I Lesion Type II Lesion Type III Lesion
Age Term, occasional stillborn   Stillborn or premature
Fetal anasarca or maternal polyhydramnios Rare Common Common
Other anomalies Rare Common Never reported
Gross appearance Single or multiple large cysts; 2-cm diameter Multiple, evenly spacedcysts; 1-cm diameter Large mass, no or tiny cysts
Histopathology
   Bronchiolar proliferation + ++ +++
   Mucoid epitheliumor cartilage Mucoid cells in one thirdof cases; rare cartilage; prominent bands of smooth muscle and elastic tissue None None
   Cyst wall Striated muscle in 5 of 16 cases
Prognosis Good Poor Poor
a Based on 21 cases with only nine neonates; four autopsies.
b + to +++ indicates increasing proportion.
c Based on 38 stillborn or newborn cases; 26 autopsies.
From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

Stocker and associates (1977) and Bale (1979) outlined the classification of these lesions based on the clinical presentation and pathologic picture (Table 80-2). A predominantly solid lung mass is usually found in the stillborn or premature infant and is associated with fetal anasarca, ascites, and maternal polyhydramnios (Fig. 80-25). The combined solid-cystic lesion may produce respiratory distress in the near-term infant at birth. The primarily cystic lesion is usually found in the older infant, child, or adult because of an associated unresolving or recurrent pneumonia (Fig. 80-26).

Fig. 80-26. A. This babygram demonstrates what appears to be multiple air-filled spaces in the left chest. The normal appearance of the gas in the abdomen suggests a cystic adenomatoid malformation in the chest rather than a congenital diaphragmatic hernia. B. A left upper lobectomy was performed. The specimen reveals both solid and cystic elements of the malformation. From Luck SR, et al: Congenital bronchopulmonary malformations. Curr Probl Surg 23:251, 1986. With permission.

Fetal ultrasound diagnosis of CCAM is being made with increasing frequency. Vergnes (1989) and McCullagh (1994) and their colleagues report that ultrasonography is a sensitive method for identifying pulmonary pathology. Prognosis and survival depend on the presence of hydrops, degree of hypoplasia of the remaining lung, size of the lesion, and timely diagnosis. Spontaneous resolution of this lesion has been reported by Mashiach and associates (1993), as well as others. Adzick and Harrison (1993) devised a useful algorithm for managing the fetus with a suspected CCAM. Adzick and colleagues (1998) reported outcomes for 124 fetuses followed during pregnancy for CCAM. Thirteen women with hydropic fetuses underwent open fetal surgery, and 8 fetuses survived. Six with a large unilocular pulmonary cyst underwent thoracoamniotic shunting and 5 fetuses survived. The remaining 101 were followed by serial ultrasonography; of these, 76 fetuses without hydrops survived. Twenty-five fetuses with hydrops died. In a prospective study of fetuses with CCAM, Crombleholme and colleagues (2002) found that the measurement of CCAM volume ratio normalized for gestational age was the best indicator of outcome. A CCAM volume ratio of greater than 1.6 predicted the development of hydrops. More frequent ultrasound examinations would be indicated

P.1116


in this group of fetuses to allow timely intervention as hydrops develops.

Surgical resection is indicated to treat the presenting symptoms. The newborn with a large CCAM presents with severe respiratory distress secondary to the space-occupying mass, the compression of the contralateral lung, and the inadequate volume of functioning lung tissue at the time of presentation. The contralateral lung may also be hypoplastic. Emergency thoracotomy and lobectomy is often life saving. In the older child or adult, surgical resection is required to remove the source of recurrent pneumonia. Granata and colleagues (1998) have updated the literature pertaining to the development of malignancy in CCAM and have suggested that resection in infancy is advisable. Luck and associates (1986) summarized the reports of malignant tumors in 10 children with cystic lung disease and advocated lobectomy for the treatment of all CCAMs, symptomatic or not.

REFERENCES

Adzick NS, Harrison MR: Management of the fetus with a cystic adenomatoid malformation. World J Surg 17:342, 1993.

Adzick NS, et al: Fetal lung lesion: management and outcome. Am J Obstet Gynecol 179:884, 1998.

Alivizatos P, et al: Pulmonary sequestration complicated by anomalies of pulmonary venous return. J Pediatr Surg 20:76, 1985.

Bale RM: Congenital cystic malformation of the lung. A form of congenital bronchiolar ( adenomatoid ) malformation. Am J Clin Pathol 71:411, 1979.

Becmeur F, et al: Pulmonary sequestrations: prenatal ultrasound diagnosis, treatment and outcome. J Pediatr Surg 33:492, 1998.

Boland RB, Schneider AF, Boggs J: Infantile lobar emphysema. Arch Pathol 61:289, 1956.

Boyden EA: Bronchogenic cysts and the theory of intralobar sequestration; new embryonic data. J Thorac Cardiovasc Surg 33:604, 1958.

Chamberlain D, et al: Pulmonary hypoplasia in babies with severe rhesus isoimmunisation: a quantitative study. J Pathol 122:43, 1977.

Claireaux A, Ferreira HP: Bilateral pulmonary agenesis. Arch Dis Child 33:364, 1958.

Cooney DR, Menke JA, Allen JE: Acquired lobar emphysema: a complication of respiratory distress in premature infants. J Pediatr Surg 12:897, 1977.

Cooney TP, Thurlbeck WM: Pulmonary hypoplasia in Down's syndrome. N Engl J Med 307:1170, 1982.

Crombleholme TM, et al: Cystic adenomatoid malformation volume ratio predicts outcome in prenatally diagnosed cystic adenomatoid malformations of the lung. J Pediatr Surg 37(3):331, 2002.

Doull IJM, Connett GJ, Warner JO: Bronchoscopic appearances of congenital lobar emphysema. Pediatr Pulmonol 21:195, 1996.

Early EK, Bothwell MR: Congenital tracheal diverticulum. Otolaryngol Head Neck Surg 127(1):119, 2002.

Egrari S, et al: Congenital bronchobiliary fistula: diagnosis and postoperative surveillance with HIDA scan. J Pediatr Surg 31:785, 1996.

Ferkol T, et al: Sinopulmonary manifestations of congenital bronchobiliary fistula. Clin Pediatr 33:181, 1994.

Floyd J, Campbell DC, Dominy DE: Agenesis of the trachea. Am Rev Respir Dis 86:557, 1962.

Gans SL, Potts WJ: Anomalous lobe of lung arising from the esophagus. J Thorac Surg 21:313, 1951.

Granata C, et al: Bronchioloalveolar carcinoma arising in congenital cystic adenomatoid malformation in a child: a case report and review on malignancies originating in congenital cystic adenomatoid malformation. Pediatr Pulmonol 25:62, 1998.

Gupta R, et al: Management of congenital lobar emphysema with endobronchial intubation and controlled ventilation. Anesth Analg 86:71, 1998.

Haller JA Jr, et al: The natural history of bronchial atresia. Serial observations of a case from birth to operative correction. J Thorac Cardiovasc Surg 79:868, 1980.

Harris HA, Lewis I: Anomalies of the lungs with special reference to the danger of abnormal vessels in lobectomy. J Thorac Cardiovasc Surg 9:666, 1940.

Haworth SG: Normal structural and functional adaptation to extrauterine life. J Pediatr 98:915, 1981.

Hershenson MB, et al: Respiratory insufficiency in newborns with abdominal wall defects. J Pediatr Surg 20:348, 1985.

Hislop A, Reid L: New pathological findings in emphysema in childhood. 1. Polyalveolar lobe with emphysema. Thorax 25:682, 1970.

Hiyama E, et al: Surgical management of tracheal agenesis. J Thorac Cardiovasc Surg 108:830, 1994.

Hubbard AM, Crombleholme TM: Anomalies and malformations affecting the fetal/neonatal chest. Semin Roentgenol 33:117, 1998.

Iwai K, et al: Intralobar pulmonary sequestration, with special reference to developmental pathology. Am Rev Respir Dis 107:911, 1973.

Jaffe RB: Balloon dilation of congenital and acquired stenosis of the trachea and bronchi. Radiology 203:405, 1997.

Kerschner J, Klotch DW: Tracheal agenesis: a case report and review of the literature. Otolaryngol Head Neck Surg 116:123, 1997.

Kim WS, et al: Cystic intrapulmonary lymphangioma: HRCT findings. Pediatr Radiol 25:206, 1995.

Kitagawa M, et al: Lung hypoplasia in congenital diaphragmatic hernia. A quantitative study of airway, artery, and alveolar development. Br J Surg 58:342, 1971.

Kuhn C, Kuhn JP: Coexistence of bronchial atresia and bronchogenic cyst: diagnostic criteria and embryologic considerations. Pediatr Radiol 22:568, 1992.

Lallemand D, Quignodon JF, Courtel JV: The anomalous origin of bronchus from the esophagus: report of three cases. Pediatr Radiol 26:179, 1996.

Lincoln JCR, et al: Congenital lobar emphysema. Ann Surg 173:55, 1971.

Luck SR, Reynolds M, Raffensperger JG: Congenital bronchopulmonary malformations. Curr Probl Surg 23:245, 1986.

Maltz DL, Nadas AS: Agenesis of the lung: presentation of eight new cases and review of the literature. Pediatrics 42:175, 1968.

Manschot HJ, Van Den Anker JN, Tibboel D: Tracheal agenesis. Anaesthesia 49:788, 1994.

Markowitz RI, et al: Congenital lobar emphysema: the roles of CT and [V with dot above]/[Q with dot above] scan. Clin Pediatr 28:19, 1989.

Mashiach R, et al: Antenatal ultrasound diagnosis of congenital cystic adenomatoid malformation of the lung: spontaneous resolution in utero. J Clin Ultrasound 21:453, 1993.

Massumi R, Taleghani M, Ellis I: Cardiorespiratory studies in congenital absence of one lung. J Thorac Cardiovasc Surg 51:561, 1966.

McCullagh M, et al: Accuracy of prenatal diagnosis of congenital cystic adenomatoid malformation. Arch Dis Child 71:F111, 1994.

McLaughlin FJ, et al: Tracheal bronchus: association with respiratory morbidity in children. J Pediatr 106:751, 1985.

Nakata H, et al: MRI of bronchogenic cysts. J Comput Assist Tomogr 17:267, 1993.

Nikaido H, Swenson O: The ectopic origin of the right main bronchus from the esophagus. A case of pneumonectomy in a neonate. J Thorac Cardiovasc Surg 62:151, 1971.

Nuchtern JG, Harberg FJ: Congenital lung cysts. Semin Pediatr Surg 3:233, 1994.

Raghavendran S, Diwan R, Shah T, et al: Continuous caudal epidural analgesia for congenital lobar emphysema: a report of three cases. Anesth Analg 93:348, 2001.

Ribet MF, Copin MC, Gosselin BH: Bronchogenic cysts of the lung. Ann Thorac Surg 61:1636, 1996.

Rubin EM, et al: Fatal massive hemoptysis secondary to intralobar sequestration. Chest 106:954, 1994.

Sakala EP, Perrott WS, Grube GL: Sonographic characteristics of antenatally diagnosed extralobar pulmonary sequestration and congenital cystic adenomatoid malformation. Obstet Gynecol Surv 49:647, 1994.

Savic B, et al: Lung sequestration: report of seven cases and review of 540 published cases. Thorax 34:96, 1979.

Say B, et al: Agenesis of the lung associated with a chromosome abnormality (46,XX,2p+). J Med Genet 17:477, 1980.

Sbokos CG, McMillan IK: Agenesis of the lung. Br J Dis Chest 71:183, 1977.

Scarpelli EA, Auld P: Pulmonary Disease of the Fetus, Newborn, and Child. Philadelphia: Lea & Febiger, 1978, p. 194.

P.1117


Stigers K, Woodring JH, Kanga JF: The clinical and imaging spectrum of findings in patients with congenital lobar emphysema. Pediatr Pulmonol 14:160, 1992.

Stocker JT, Madewell JE, Drake RM: Congenital cystic adenomatoid malformation of the lung. Hum Pathol 8:155, 1977.

Stovin P: Congenital lobar emphysema. Thorax 14:254, 1959.

Swischuk LE, et al: Primary pulmonary hypoplasia and the neonate. J Pediatr 95:573, 1979.

Tapper D, et al: Polyalveolar lobe: anatomic and physiologic parameters and their relationship to congenital lobar emphysema. J Pediatr Surg 15:931, 1980.

Thilenius OG, et al: Spectrum of pulmonary sequestration: association with anomalous pulmonary venous drainage in infants. Pediatr Cardiol 4:97, 1983.

Tommasoni N, et al: Congenital tracheobiliary fistula. Pediatr Pulmonol 30:149, 2000.

Van Klaveren RJ, et al: Congenital bronchial atresia with regional emphysema associated with pectus excavatum. Thorax 47:1082, 1992.

Vergnes P, et al: Antenatal diagnosis of lung malformations. Apropos of 9 case reports. Chir Pediatr 30:185, 1989.

Vevecka E, et al: Tracheal bronchus associated with congenital cystic adenomatoid malformation. Pediatr Pulmonol 20:413, 1995.

Vilos GA, et al: Absence or impaired response of fetal breathing to intravenous glucose is associated with pulmonary hypoplasia in congenital myotonic dystrophy. Am J Obstet Gynecol 148:558, 1984.

Wigglesworth JS, Desai R: Effect on lung growth of cervical cord section in the rabbit fetus. Early Hum Dev 3:51, 1979.

Wong KS, Wang CR, Hsieh KH: Demonstration of tracheal bronchus associated with tracheal stenosis using direct coronal computed tomography. Pediatr Pulmonol 25:133, 1998.



General Thoracic Surgery. Two Volume Set. 6th Edition
General Thoracic Surgery (General Thoracic Surgery (Shields)) [2 VOLUME SET]
ISBN: 0781779820
EAN: 2147483647
Year: 2004
Pages: 203

flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net