Fetal pleuroamniotic shunting for bronchopulmonary sequestration with hydrops

Minimally Invasive Fetal Surgery and the Next Frontier

Most patients with congenital anomalies do not require prenatal intervention. Furthermore, many congenital anomalies requiring surgical intervention are treated adequately after birth. However, there is a subset of patients with congenital anomalies who will die before birth, shortly after birth, or experience severe postnatal complications without fetal surgery. Fetal surgery is unique in that an operation is performed on the fetus as well as the pregnant woman who does not receive any direct benefit from the surgery but rather lends herself to risks, such as hemorrhage, abruption, and preterm labor. The maternal risks involved with fetal surgery have limited the extent to which fetal interventions may be performed but have, in turn, led to technical innovations that have significantly advanced the field. This review will examine congenital abnormalities that can be treated with minimally invasive fetal surgery and introduce the next frontier of prenatal management of fetal surgical pathology.

Management Options for Fetal Bronchopulmonary Sequestration

To evaluate the prenatal course and perinatal outcome of fetuses with bronchopulmonary sequestration (BPS) managed expectantly or using minimally invasive methods. This was a retrospective study of 29 fetuses with suspected BPS managed between 2010 and 2021 in three fetal medicine centers in Poland. Medline was searched to identify cases of BPS managed expectantly or through minimally-invasive methods. In 16 fetuses with BPS, there was no evidence of cardiac compromise. These fetuses were managed expectantly. Thirteen hydropic fetuses with BPS qualified for intrauterine intervention: a thoraco-amniotic shunt (TAS) was inserted in five fetuses, laser coagulation of the feeding vessel was performed in seven cases, and one fetus had combined treatment. In the combined data from the previous and the current study of various percutaneous interventions for BPS associated with hydrops, the survival rate was 91.2% (31/34) for TAS, 98.1% (53/54) for laser coagulation, and 75% (3/4) for intratumor injection of sclerosant. After taking into account cases with available data, the rate of preterm birth before 37 weeks in the group treated with laser coagulation was 14.3% (7/49) compared to 84.6% (22/26) in the group treated with TAS. The need for postnatal sequestrectomy was lower in the group of fetuses treated with laser coagulation 23.5% (12/51) in comparison to fetuses treated with TAS 84% (21/26). In fetuses with BPS without hydrops, progression of the lesion’s volume, leading to cardiac compromise, is unlikely. In hydropic fetuses with BPS, intrauterine therapy using minimally invasive methods prevents fetal demise. Both, the rate of preterm birth and the need for postnatal surgery is significantly lower in the group treated with laser coagulation compared to the group treated with TAS.

Bronchopulmonary sequestration with massive pleural effusion: pleuroamniotic shunting vs intrafetal vascular laser ablation

OBJECTIVE

To assess the incidence of complications among a relatively large cohort of fetuses with bronchopulmonary sequestration (BPS) and the success of two different intrauterine treatment modalities.

METHODS

All cases with a prenatal diagnosis of BPS detected in a 10-year period (2002-2011) in two tertiary referral centers were reviewed retrospectively for intrauterine course and outcome. Up to May 2010 severe pleural effusions were treated with pleuroamniotic shunting. Thereafter, they were treated with ultrasound-guided laser coagulation of the feeding artery.

RESULTS

A total of 41 fetuses with BPS were included in the study. In 29 (70.7%) there was no pleural effusion or hydrops and they were treated conservatively. In 19/29 (65.5%) there was partial or complete regression of the lesion during the course of pregnancy. All were born alive (median age at delivery, 38.3 (interquartile range (IQR), 34.0-39.6) weeks) and 16 (55.2%) required sequestrectomy. Intrauterine intervention was performed in all 12 (29.3%) fetuses with pleural effusion. Seven fetuses were treated with pleuroamniotic shunting. One fetus with severe hydrops died in utero. There was no complete regression in any case of BPS in this group. Six infants were born alive (median age, 37.2 (IQR, 30.3-37.4) weeks), of which five (83.3%) required sequestrectomy. Five fetuses were treated with laser ablation of the feeding vessel. In all cases of BPS there was regression after laser ablation. All infants were delivered at term (median age, 39.1 (IQR, 38.0-40.0) weeks). One (20.0%) neonate required sequestrectomy after birth. Following intrauterine shunt placement complete regression of the lesion was significantly less frequent (0/7 (0%) with shunt placement vs 4/5 (80%) with intrafetal laser treatment) and gestational age at birth was significantly lower, compared to treatment with intrafetal laser. Complete regression of the lesion was also significantly more frequent in the laser group compared to cases without intervention.

CONCLUSION

In the absence of pleural effusion, the likelihood of spontaneous regression of BPS is high and the prognosis is therefore favorable. In cases with massive pleural effusion, treatment by laser ablation of the feeding vessel seems to be more effective than is pleuroamniotic shunting, with fewer complications. It might also reduce the need for postnatal surgery.

Minimally invasive fetal therapy for hydropic lung masses: three different approaches and review of the literature

OBJECTIVE

To report three different antenatal therapeutic approaches for fetal lung masses associated with hydrops.

METHODS

Three prospectively followed cases are described, and all 30 previously published minimally invasive cases of fetal therapy for hydropic lung masses are reviewed.

RESULTS

Three hydropic fetuses with large intrathoracic lung masses presented at 17, 25 and 21 weeks of gestation, respectively. An aortic feeding vessel was identified in each case and thus a bronchopulmonary sequestration (BPS) was suspected. Under ultrasound guidance, the feeding vessel was successfully occluded with interstitial laser (Case 1), radiofrequency ablation (RFA) (Case 2) and thrombogenic coil embolization (Case 3). Complete (Cases 1 and 2) or partial (Case 3) resolution of the lung mass and hydrops was observed. A healthy infant was born at term after laser therapy (Case 1), and the involved lung lobe was resected on day 2 of postnatal life. In Case 2, hydrops resolved completely following RFA, but an iatrogenic congenital diaphragmatic hernia and abdominal wall defect became apparent 4 weeks later. The neonate died from sepsis following spontaneous preterm labor at 33 weeks. In Case 3, despite technical success in complete vascular occlusion with coils, a stillbirth ensued 2 days after embolization.

CONCLUSIONS

The prognosis of large microcystic or echogenic fetal chest masses associated with hydrops is dismal. This has prompted attempts at treatment by open fetal surgery, with mixed results, high risk of premature labor and consequences for future pregnancies. We have demonstrated the possibility of improved outcome following ultrasound-guided laser ablation of the systemic arterial supply. Despite technical success, RFA and coil embolization led to procedure-related complications and need further evaluation.

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.

Grayscale and Doppler sonographic evaluation of response to in utero treatment of hydrops fetalis caused by extralobar pulmonary sequestration

Pulmonary sequestration is defined as nonfunctional lung tissue that lacks communication with the bronchial tree and that is supplied by an anomalous systemic vessel. In comparatively rare cases, pulmonary sequestration may lead to hydrothorax or hydrops fetalis, which is nearly universally fatal. In this report, we describe a case of pulmonary sequestration with hydrops fetalis, which was successfully treated by thoracoamniotic shunting. A sonographic Doppler study in this case suggested that the underlying mechanism of the hydropic change in a fetus with extralobar pulmonary sequestration may have differed from that in fetuses with primary hydrothorax not associated with a structural anomaly.

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.

Congenital primary hydrothorax: effect of thoracoamniotic shunting on neonatal clinical outcome

BACKGROUND

Spontaneous regression in the foetal period has been described for congenital hydrothorax. Hydrothorax may become larger and bilateral with hydrops and pulmonary hypoplasia. Prenatal thoracentesis and thoracoamniotic shunting of massive hydrothorax are indicated to decrease perinatal morbidity. In the neonatal period, persistent hydrothorax may require intensive care.

OBJECTIVE

To investigate neonatal outcome after thoracoamniotic shunting for congenital primary hydrothorax with hydrops/ polydramnios.

METHODS

Retrospective study on the postnatal management of a cohort of 28 congenital primary hydrothorax cases after thoracoamniotic shunting (January 2000-August 2005).

RESULTS

Congenital hydrotorax without major structural anomalies complicated by polidramnios and/or hydrops<34 weeks' gestation were the criteria accepted for thoracoamniotic shunting. There were neither pregnancy terminations nor utero deaths. Although 64% of cases were complicated by severe neonatal respiratory insufficiency, neonatal mortality rate was low (21.4%) if compared with literature. Univariate analysis identified 'birth at gestational age (GA)<35 weeks' and 'time between prenatal shunting and birth' as predictive factors for needing of ventilation. Multivariate analysis identified 'birth at GA<35 weeks' as the only independent predictor for needing ventilation. (OR=0.08, CI 95%=0.01-0.96, p=0.046). No risk factors for death or adverse neurological outcomes were reported.

CONCLUSIONS

Congenital hydrothorax although corrected by thoracoamniotic shunting is complicated by severe respiratory distress. The neonatal outcome may be improved limiting degree of prematurity; the presence of thoracoamniotic shunt is not per se an indication of premature birth, at least until GA>35 weeks and adequate pulmonary maturity is reached.

Single-needle laser treatment with drainage of hydrothorax in fetal bronchopulmonary sequestration with hydrops

Bronchopulmonary sequestration (BPS) is sometimes associated with hydrothorax and hydrops in utero. In the absence of fetal hydrops, perinatal outcome is favorable and justifies expectant management. In the presence of fetal hydrops, perinatal outcome is reported to be extremely poor and intervention should be considered. Therapeutic options include open fetal surgery, minimally invasive coagulation of the blood supply and thoracoamniotic shunting. We present the first case of fetal hydrops and a large hydrothorax due to BPS treated successfully with one ultrasound-guided thin needle insertion, through which both laser coagulation of the feeding artery and drainage of the hydrothorax were performed. Following the procedure the hydrothorax and hydrops gradually disappeared and the BPS diminished in size. A healthy neonate was delivered uneventfully at term. We describe the case and discuss the different therapeutic options.

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.

Fetal pleural effusions

The clinical course of primary fetal hydrothorax is unpredictable. Whereas smaller unilateral effusions might remain stable or even regress, this is rarely the case with larger collections. Bilateral effusions, hydrops, preterm delivery and the lack of antenatal therapy are all associated with poor outcome. Once structural and chromosomal anomalies have been excluded, optimal management depends on gestational age, rate of progression, the development of hydrops and associated maternal symptoms. For very large effusions with mediastinal shift, hydrops and/or hydramnios, or when there is rapid enlargement of the effusion, fetal intervention is warranted. Survival can be maximized by pleuroamniotic shunting, which can reverse hydrops and hydramnios and prevent pulmonary hypoplasia. Pleuroamniotic shunting can also be used for the treatment of other large cystic lung lesions, such as a macrocystic congenital cystic adenomatoid malformation or bronchopulmonary sequestration, especially when associated with hydrops.