**3.2. Ultrasound diagnosis**

The prenatal ultrasound diagnosis of bronchopulmonary sequestration is based on the following elements:

• hyperechoic mass

Karyotyping is not an indication if other anomalies are not present. However, amniocentesis for karyotyping is appropriate if fetal treatment is balanced or when the parents request it [14]. The attitude in CCAM associated with hydrops depends on the CVR value. Thus, if the CVR is less than 1.6 and we do not have a dominant cyst, then weekly fetal monitoring is indicated to identify early signs of hydrops. If we are dealing with a dominant cyst, even if CVR is less than 1.6, the fetus has a major risk of developing hydrops and a thoracoamniotic shunt should be considered at first signs of hydrops appearance. If CVR is above 1.6, the likelihood

The fetal therapy available nowadays is as follows: corticotherapy, in utero fine needle aspiration of macrocysts or thoracoamniotic shunt, laser vascular ablation and, finally, sclerotherapy [15]. A fetus with hydrops below 32-week gestation with a macrocystic lesion of CCAM

Corticosteroid treatment can be followed by the regression of the mass and it is especially indicated in cases of microcystic lesions. If CVR is equal to 1.6, corticosteroid therapy is indicated. Either fine needle aspiration or thoracoamniotic shunt improve the outcome of fetuses with macrocystic CCAM complicated with hydrops/hydrothorax. Microcystic lesions resulting in fetal hydrops of CCAM may need laser ablation of the feeding vessel, to improve survival and with regression of the lesion. The sclerotherapy is also indicated in microcystic cases and it is used Ethanolamine. But it must be emphasized that in most cases fetal CCAM needs only serial fetal surveillance, every 2 or 3 weeks, to confirm regression in size or the remaining

Bronchopulmonary sequestration (BPS) represents a cystic mass of nonfunctioning pulmonary tissue with the blood supply from the systemic vessels and not from the pulmonary

Pulmonary sequestration can be: intrapulmonary and extrapulmonary. Intrapulmonary sequestration (IPS) represents almost 75% of the cases, but this form is rarely diagnosed in utero. The abnormal lung tissue lies within the normal lung tissue. This variety is produced

Extrapulmonary sequestration (EPS) is the most commonly form diagnosed in the prenatal life. The abnormal lung tissue has its own pleural covering, so the abnormal pulmonary tissue is separated from the normal pulmonary tissue and the pathologic tissue drains in the systemic circulation. The extrapulmonary sequestration is considered to be an abnormal pulmonary tissue that has no connection with the bronchial tree. The vascularization is provided

The incidence reported is 0.5–6.0% of all prenatally diagnosed pulmonary lesions [16].

of developing hydrops is very high and monitoring is required 2 times a week.

will benefit from thoracoamniotic shunt. Also, the surgical resection is an option.

at the same size.

arteries.

**3. Bronchopulmonary sequestration**

172 Congenital Anomalies - From the Embryo to the Neonate

**3.1. Definition and incidence**

by the bronchial obstruction.

by arteries emerging from the aorta.


Typically, BPS vascularization, and more specifically EPS, is supplied by a single artery, originating from the aorta (**Figure 10**).

The veins of the BPS drain in the azygos system and hemiazygos. At the opposite end, the venous drainage of the IPS is achieved through the pulmonary veins [17]. The hydrothorax can be associated with BPS, usually ipsilateral, and if it is important, it can cause a mediastinal shift.

Differential diagnosis includes the following: CCAM, bronchial atresia, lobar emphysema, CDH-particularly when the liver or spleen is the only component of herniation, mediastinal teratoma, neuroblastoma, mesoblastic nephroma, segmental thoracic obstruction, and thoracic kidney.

The differential diagnosis between CCAM and BPS, when no systemic feeding vessel is evident, is based on the echogenicity of the mass: the presence of cyst suggests CCAM, while the presence of a hyperechogenic triangular mass suggests BPS (**Figure 11**).

For extrapulmonary BPS, the differential diagnosis includes: mesoblastic nephroma, and neuroblastoma.

**Figure 10.** Bronchopulmonary sequestration: systemic vascularization.

anomalies and bronchogenic cyst. Fetal monitoring is required in the prenatal period, to identify the appearance of the hydrothorax. A fetus with isolated BPS has good chances of survival in the absence of hydrops, polyhydramnios or pleural effusion, because it can regress in 80% of cases. Fetuses over 30-week gestation should be considered for preterm delivery and ex-utero surgical resection. In the presence of hydrops before 30 weeks, placing a thoracoamniotic shunt may be offered. In hydrothorax, installing the thoraco-amniotic shunt may prevent the development of fetal hydrops. The postnatal therapy consists of the endoscopic removal of the pulmonary mass

Thoracic Anomalies

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http://dx.doi.org/10.5772/intechopen.71959

In brief, for the two main anomalies CCAM and BPS, we can apply the following therapeutic

• CCAM/BPS stable as dimensions and stationary as evolution: near-term birth and ex-utero

• Progressive CCAM/BPS towards hydrops and mediastinal shift: it depends on the gestational age of the fetus. Thus, if it is less than 32 weeks, then a thoraco-amniotic shunt or resection in utero and cesarean delivery is recommended near term. After 32 weeks' gesta-

Congenital pulmonary hypoplasia consists of the lowering of the lung volume in comparison to the lung volume corresponding to the gestational age. The causes of pulmonary hypoplasia are represented by: congenital diaphragmatic hernia (CDH), oligohydramnios, skeletal dysplasia, chest tumors, neuromuscular disorders that obstruct fetal respiratory movements. A rare cause is represented by the obstructive cardiac abnormalities of the right-sided heart, which may be accompanied either by the absence of the development of a single lung or the absence of the development of both lungs. Regardless the mechanism, pulmonary hypoplasia is responsible for the neonatal mortality, of 10–15% [23]. Pulmonary agenesis can be classified into three groups [23, 24]: in group 1, there are bronchial and lung agenesis, in group 2 there is a rudimentary bronchus without bronchial tissue and in group 3 it is a bronchial hypoplasia and a hypoplasia of lung tissue. Pulmonary agenesis is usually unilateral, and occurs at 4 weeks of gestation. The etiology of this anomaly is unknown. The incidence of pulmonary agenesis, either unilateral or bilateral, is very low, 0.0097% or 1 at 10,000 pregnancy [22]. More than half of the fetuses with pulmonary agenesis have other associated abnormalities: gastrointestinal, cardiovascular and genitourinary. Unilateral pulmonary agenesis may be associated with numerous other abnormalities: patent ductus arteriosus (PDA), atrial and ventricular septal defects, anomalous pulmonary venous drainage, tracheoesophageal fistula and duodenal atresia, hemivertebrae with scoliosis, facial abnormalities and limb abnormalities.

tional age, the iatrogenic preterm birth and resection ex utero are recommended.

and alternatively the selective embolization of the artery that feeds the tumor [20–22].

• Regressive CCAM/BPS: term delivery and evaluation

**4. Pulmonary hypoplasia and pulmonary agenesis**

scheme:

resection

**4.1. Definition and incidence**

**Figure 11.** Differential diagnosis CCAM versus BPS.

## **3.3. Prognosis**

The prognosis of BPS is favorable in the absence of other associated abnormalities. In many case series it was found that, similar to CCAM evolution and in BPS cases, there is often present a regression of the lesion [18, 19]. However, in fetuses with BPS associated with fetal hydrops, the prognosis is poor (**Figure 12**).

Fetal hydrops occurs only if a tension hydrothorax develops. The cause of unilateral hydrothorax associated with BPS is not well-defined. The torsion of a vascular pedicle or abnormal pressure gradient between the systemic artery and the pulmonary vein may be the cause [19]. Regardless the etiology, the persistence of the hydrothorax causes pulmonary compression with pulmonary hypoplasia and the impairment of the caval venous drainage due to mediastinal shift.

### **3.4. Prenatal management**

In isolated BPS karyotyping is not mandatory, but it is recommended if any other abnormality is associated. Fetal MRI may be useful for differential diagnosis. The family may choose to terminate the pregnancy if the diagnosis is established before 24 weeks and it is associated with other abnormalities such as: esophageal atresia, neurenteric cyst, CDH, pulmonary hypoplasia, cardiac

**Figure 12.** Fetal hydrops and BPS: arrow—BPS mass, star—hydrothorax.

anomalies and bronchogenic cyst. Fetal monitoring is required in the prenatal period, to identify the appearance of the hydrothorax. A fetus with isolated BPS has good chances of survival in the absence of hydrops, polyhydramnios or pleural effusion, because it can regress in 80% of cases. Fetuses over 30-week gestation should be considered for preterm delivery and ex-utero surgical resection. In the presence of hydrops before 30 weeks, placing a thoracoamniotic shunt may be offered. In hydrothorax, installing the thoraco-amniotic shunt may prevent the development of fetal hydrops. The postnatal therapy consists of the endoscopic removal of the pulmonary mass and alternatively the selective embolization of the artery that feeds the tumor [20–22].

In brief, for the two main anomalies CCAM and BPS, we can apply the following therapeutic scheme:

