Successful Intrauterine Therapy for Congenital Cystic Adenomatoid Malformation of the Lung

Current perspective and scope of fetal therapy: part 1

Fetal therapy term has been described for any therapeutic intervention either invasive or noninvasive for the purpose of correcting or treating any fetal malformation or condition. Fetal therapy is a rapidly evolving specialty and has gained pace in last two decades and now fetal intervention is being tried in many malformations with rate of success varying with the type of different fetal conditions. The advances in imaging techniques have allowed fetal medicine persons to make earlier and accurate diagnosis of numerous fetal anomalies. Still many fetal anomalies are managed postnatally because the fetal outcomes have not changed significantly with the use of fetal therapy and this approach avoids unnecessary maternal risk secondary to inutero intervention. The short-term maternal risk associated with fetal surgery includes preterm labor, premature rupture of membranes, uterine wall bleeding, chorioamniotic separation, placental abruption, chorioamnionitis, and anesthesia risk. Whereas, maternal long-term complications include risk of infertility, uterine rupture, and need for cesarean section in future pregnancies. The decision for invasive fetal therapy should be taken after discussion with parents about the various aspects like postnatal fetal outcome without fetal intervention, possible outcome if the fetal intervention is done, available postnatal intervention for the fetal condition, and possible short-term and long-term maternal complications. The center where fetal intervention is done should have facility of multi-disciplinary team to manage both maternal and fetal complications. The major issues in the development of fetal surgery include selection of patient for intervention, crafting effective fetal surgical skills, requirement of regular fetal and uterine monitoring, effective tocolysis, and minimizing fetal and maternal fetal risks. This review will cover the surgical or invasive aspect of fetal therapy with available evidence and will highlight the progress made in the management of fetal malformations in last two decades.

Congenital pulmonary airway malformation: advances and controversies

Advances in antenatal screening have provided evidence that the prevalence of congenital pulmonary airway malformation is higher than previously thought. This means that, on a global scale, more congenital pulmonary airway malformations will be diagnosed and seen by clinicians across many different specialties. This increase poses new controversies and challenges for clinicians in terms of prenatal and postnatal management. Important and exciting research has begun to emerge in the past decade. This Review describes current understanding of the disease, the latest surgical developments, and highlights management issues and controversies, including the rationale and timing of surgical intervention, the choice of surgical approach, and long-term functional outcomes. In doing so, we attempt to provide a balanced management algorithm for readers.

Percutaneous laser ablation under ultrasound guidance for fetal hyperechogenic microcystic lung lesions with hydrops: a single center cohort and a literature review

OBJECTIVE

To evaluate the perinatal outcomes in hydropic fetuses with congenital microcystic pulmonary lesions that underwent percutaneous, invasive, laser therapy.

METHOD

This retrospective study reviews the literature and our experience between 2004 and 2010. Characteristics of the cystic lung lesions, liquor volume (presence of polyhydramnios or not), localization of ablation (vascular vs interstitial) and gestational age at which the procedure was performed were related to outcome (survival).

RESULTS

In total, 16 fetuses with congenital lung lesions underwent 'invasive' percutaneous laser ablation, seven performed in our center and nine published cases. Survival rate was higher in fetuses with a subsequent postnatal diagnosis of bronchopulmonary sequestration (87.5%) compared with congenital adenomatoid malformation (28.6%; p = 0.04). The technique of vascular ablation was more successful (100%) than interstitial ablation (25.0%, p < 0.01).

CONCLUSION

Percutaneous vascular laser ablation seems to be effective for bronchopulmonary sequestration in hydropic fetuses. Outcomes were worst following interstitial ablation for microcystic congenital adenomatoid with hydrops.

Neonatal outcome after prenatal interventions for congenital lung lesions

Congenital lung lesions, mostly congenital cystic adenomatoid malformations (CCAMs) and bronchopulmonary sequestrations (BPSs), are uncommon disorders. Prenatal intervention in severely affected (hydropic) fetuses has drastically improved perinatal survival. Not much is known, however, on the short-term and long-term respiratory and neurodevelopmental outcome. Several small case series have been reported and suggest an increased incidence of neonatal morbidity, mainly associated with prematurity and respiratory failure at birth. Overall, neonatal mortality and morbidity after prenatal interventions for CCAM seems to be worse than for BPS. This review focuses on the neonatal outcome after prenatal intervention for congenital lung lesions and summarizes the results reported in the literature.

Prenatal interventions for fetal lung lesions

The widespread availability of high resolution ultrasound equipment and almost universal routine anatomy scanning in all pregnant women in the developed world has lead to increased detection of abnormalities in the fetal thorax. Already in the 1980s, large pleural effusions and significant macrocystic lesions in the fetus were easily detected on ultrasound. However, smaller lung tumours were often missed. Nowadays, fetal medicine centres receive many referrals for evaluation of fetal lung lesions, of which the most common are congenital cystic adenomatoid malformation and bronchopulmonary sequestration. Almost invariably, both the parents and the referring physicians experience anxiety after detection of large lung masses in the fetus. However, the vast majority of the currently detected fetal lung lesions have an excellent prognosis without the need for prenatal intervention. In the small group of fetuses in which the prognosis is poor, almost exclusively those with concomitant fetal hydrops and cardiac failure, several options for fetal therapy exist, often with a more than 50% survival rate. Indications, techniques, complications and outcomes of these interventions will be described in this review.

Prenatal diagnosis and outcome of echogenic fetal lung lesions

OBJECTIVE

To describe the antenatal findings and outcome of fetuses with echogenic lung lesions.

METHODS

This was a retrospective study of the prenatal sonographic features, antenatal management and outcome of 193 fetuses with an echogenic lung lesion diagnosed at 18-35 weeks of gestation. There were nine cases of congenital high airway obstruction syndrome (CHAOS), 170 cases of cystic adenomatoid malformation (CAM) and 14 cases of pulmonary sequestration (PS). A literature search was also carried out to compare our data with those of previous series.

RESULTS

The prognosis in our series of fetuses with CHAOS was invariably poor, but the literature describes a handful of survivors after delivery by Cesarean section and ex-utero intrapartum therapy (EXIT). Of the cases in our series with PS and no pleural effusions, more than 95% survived; in half of these cases the lesion resolved antenatally and in the other half sequestrectomy was carried out postnatally. In cases with PS and pleural effusions, successful treatment was provided by the placement of thoracoamniotic shunts or occlusion of the feeding blood vessel by ultrasound-guided laser coagulation or injection of sclerosants. In cases with CAM and no hydrops, there was more than 95% survival and in up to half of the cases there was sonographic evidence of spontaneous antenatal resolution of the hyperechogenic lesion, which was confirmed by postnatal imaging in about 60% of the cases. Of the cases with CAM with hydrops managed expectantly, more than 95% died before or after birth. Of the cases with macrocystic CAM with hydrops, two-thirds survived after placement of a thoracoamniotic shunt. In cases with microcystic CAM with hydrops, there is some evidence that open fetal surgery with lobectomy could improve survival but such treatment is highly invasive for the mother.

CONCLUSIONS

CHAOS is a severe abnormality, whereas CAM and PS are associated with a good prognosis. In a high proportion of fetuses with hyperechogenic lung lesion, there is spontaneous antenatal resolution and the underlying pathology may be transient bronchial obstruction.