Prenatal diagnosis of pulmonary sequestration using three-dimensional power Doppler ultrasound

Antenatal diagnosis of bronchopulmonary sequestration: A case report and review of the literature

Congenital lung malformations are a constellation of pathologies that can be diagnosed antenatally by ultrasound and fetal MRI. Ultrasound is considered the modality of choice for a routine assessment of second-trimester scans worldwide. Bronchopulmonary sequestration (BPS) and congenital pulmonary airway malformation (CPAM) are the 2 most common echogenic chest masses discovered incidentally during routine ultrasound scans in the second trimester. This paper describes BPS and differentiates it from CPAM sonographically in utero. An extensive literature search involving antenatal ultrasound is undertaken to review the most up-to-date understanding of the BPS. Furthermore, a case study at our institution and the literature review will help better describe the salient features of BPS. A 41-year-old female G3P1 visits our department for a routine second-trimester ultrasound. An echogenic lesion with a cystic component is visualized in this scan. Based on the grayscale and color imaging, this complex echogenic lesion was reported as CPAM and was referred to fetal assessment for confirmation. The fetal assessment diagnosed the lesion as BPS because of the pathognomonic feeding vessel from the thoracic aorta. Regardless of the congenital lung mass, any large mass compromising fetal well-being is an indication for intervention. The prognosis of BPS in the absence of fetal hydrops is excellent. A robust collaboration among radiologists, obstetricians, and pediatricians is required for the best outcome for the pregnancy and the neonate.

Prenatal screening and diagnosis of pulmonary artery anomalies

Congenital pulmonary artery anomalies are rare. Their antenatal diagnosis requires good knowledge of fetal cardiac anatomy because their clinical presentation varies depending on the type and severity of the underlying lesion. Screening of these vascular anomalies can be straightforward in some cases because of significant associated consequences that are detected easily on ultrasound, while other anomalies have considerably less obvious features. There may be an associated genetic syndrome. The aim of this review was to define anomalies of the main pulmonary artery and its branches and to propose, through the identification of suspicious findings during routine antenatal heart examination, an optimal screening method for the pulmonary artery pathway. We propose that pulmonary artery anomalies can be classified antenatally into four types of disorder. Herein we describe 14 cases subgrouped accordingly as: anomalies of the pulmonary valvular region, with stenosis or atresia of the valve (n = 4); conotruncal abnormalities (n = 4); anomalies associated with abnormal origin or course of the pulmonary artery (n = 4); and anomalies associated with abnormal growth of the pulmonary artery and its branches (n = 2). We highlight the need to differentiate the three-vessel view from the three-vessel-and-trachea view when assessing a fetus with a congenital pulmonary artery anomaly. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Congenital lung malformations: Dysregulated lung developmental processes and altered signaling pathways

Congenital lung malformations comprise a diverse group of anomalies including congenital pulmonary airway malformation (CPAM, previously known as congenital cystic adenomatoid malformation or CCAM), bronchopulmonary sequestration (BPS), congenital lobar emphysema (CLE), bronchogenic cysts, and hybrid lesions. Little is known about the signaling pathways that underlie the pathophysiology of these lesions and the processes that may promote their malignant transformation. In the last decade, the use of transgenic/knockout animal models and the implementation of next generation sequencing on surgical lung specimens have increased our knowledge on the pathophysiology of these lesions. Herein, we provide an overview of normal lung development in humans and rodents, and we discuss the current state of knowledge on the pathophysiology and molecular pathways that are altered in each congenital lung malformation.

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.

Prediction of postnatal outcome in fetuses with congenital lung malformation: 2-year follow-up study

OBJECTIVES

To identify, in fetuses with a congenital lung malformation (CLM), prenatal predictors of the need for postnatal respiratory support and the need for surgery by calculating the CLM volume ratio (CVR), and to evaluate the concordance between the prenatal appearance and the postnatal type of CLM.

METHODS

This was an analysis of prenatal, perinatal and postnatal data from fetuses diagnosed with a CLM at the Erasmus University Medical Center - Sophia Children's Hospital in Rotterdam, The Netherlands, between January 2007 and December 2016. For all included fetuses, CVR was measured retrospectively on stored ultrasound images obtained at 18 + 1 to 24 + 6 weeks (US1), 25 + 0 to 29 + 6 weeks (US2) and/or 30 + 0 to 35 + 6 weeks' gestation (US3). Postnatal diagnosis of CLM was based on computed tomography or histology. Primary outcomes were the need for respiratory support within 24 h and surgery within 2 years after birth.

RESULTS

Of the 80 fetuses with a CLM included in this study, 14 (18%) required respiratory support on the first postnatal day, and 17 (21%) required surgery within 2 years. Only the CVR at US2 was predictive of the need for respiratory support, with a cut-off value of 0.39. Four of 16 (25%) fetuses which showed full regression of the CLM prenatally required respiratory support within 24 h after birth. The CVR at US1, US2 and US3 was predictive of surgery within 2 years. Overall, the prenatal appearance of the CLM showed low concordance with the postnatal type. Prenatally suspected microcystic congenital pulmonary airway malformation (CPAM) was shown on computed tomography after birth to be congenital lobar overinflation in 15/35 (43%) cases. Respiratory support within 24 h after birth and surgical resection within 28 days after birth were needed in all cases of macrocystic CPAM.

CONCLUSIONS

CVR can predict the need for respiratory support within 24 h after birth and for surgery within 2 years. Regression of a CLM prenatally does not rule out respiratory problems after birth. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. - Legal Statement: This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

Narrative review of congenital lung lesions

This article reviews the contemporary diagnosis and management of antenatally diagnosed congenital lung lesions. These anomalies, which include congenital pulmonary airway malformation (CPAM) (formerly congenital cystic adenomatoid malformation), bronchopulmonary sequestration (BPS), bronchogenic cyst, and congenital lobar emphysema (CLE), are relatively rare but are increasingly encountered by clinicians because of the improved resolution and enhanced sensitivity of fetal ultrasound. Serial assessment of these lesions throughout pregnancy remains the norm rather than the exception. Perinatal management strategies may differ based on initial size and growth patterns of these masses until delivery. Fetal magnetic resonance imaging and other diagnostic testing can sometimes be helpful in providing additional prognostic information. Over the last decade, maternal steroids have become standard of care in the management of larger lesions at risk for nonimmune hydrops. As a result, fetal surgical procedures, including open resection, thoracoamniotic shunting, and ex utero intrapartum treatment (EXIT), are less uncommonly performed. Decisions regarding whether delivery of these fetuses should occur in a tertiary care center with pediatric surgery coverage versus delivery at a local community hospital are now highly relevant in most prenatal counseling discussions with families. Large lung malformations may require urgent surgical removal in the early postnatal period because of respiratory distress. Other complications, such as recurrent pneumonia, pneumothorax, and cancer, are indications for postnatal lung resection on an elective basis. Many children are good candidates for minimally invasive (thoracoscopic) surgical approaches as an alternative to resection by thoracotomy. In the vast majority of cases, the overall prognosis remains excellent.

Antenatal Management of Bronchopulmonary Sequestration by Intrafetal Vascular Laser Ablation under Ultrasound Control: Narrative Review of the Literature and Report of Three Cases

OBJECTIVE

The objective of this study is to assess the effectiveness and safety of intrafetal vascular laser ablation (VLA) for fetuses with bronchopulmonary sequestration (BPS) with hydrops.

METHODS

First, we present 3 cases of fetuses with BPS and hydrops treated by VLA. Second, we aimed to conduct a narrative review to identify all reported cases of fetuses with BPS treated by intrafetal VLA.

RESULTS

The review of the literature identified 41 fetuses treated by VLA for BPS with hydrops. The median gestational age of the VLA was 27+0 weeks' gestation [25+0-31+0] with an associated procedure at the same time in 43% of the cases (pleuroamniotic shunt, thoracentesis, and amniodrainage). A second procedure was required in 25% of cases for residual flow in the feeding vessel. No stillbirth or neonatal death was reported. The complications reported were a fetal thoracic hematoma complicated by fetal anemia and 4 preterm deliveries with a rate of 9%.

CONCLUSION

VLA of the feeding vessel can be an effective treatment but is not without complications. In cases demonstrating cardiac output failure, intrafetal VLA should be considered as a treatment for BPS.

Intraoperative real-time hemodynamics in intralobar pulmonary sequestration using indocyanine green and near-infrared thoracoscopy

A 33-year-old man with left pulmonary sequestration was admitted to our hospital. We planned left basilar segmentectomy to preserve the lung function, using indocyanine green (ICG) and near-infrared thoracoscopy. The intravenous (IV) administration of ICG (0.1 mg/kg) showed the distribution of fluorescence from the aberrant arteries, blood flow blockage from the aberrant arteries after they were divided, and the superior-basal boundary after the pulmonary artery and vein were divided. In adult patients with intralobar pulmonary sequestration, ICG and near-infrared thoracoscopic techniques are useful to confirm abnormal hemodynamics and demonstrate a safe and successful basilar segmentectomy.

Congenital lung lesions

Diagnosis and management of congenital lung malformations has evolved dramatically over the past several decades. Advancement in imaging technology has enabled earlier, more definitive diagnoses and, consequently, more timely intervention in utero or after birth, when indicated. These advancements have increased overall survival rates to around 95% from historical rates of 60%. However, further refinement of diagnostic technique and standardization of treatment is needed, particularly as the increased sensitivity of diagnostic imaging results in more frequent diagnoses. In this article, we provide an updated review of the diagnostic strategies, management, and prognosis of congenital lung malformations.

Congenital Lung Malformations

Congenital lung malformations (CLM) comprise a spectrum of anatomical anomalies of the lungs and respiratory tree. The prenatal growth pattern of CLMs is unpredictable with larger lesions causing life-threatening complications, such as hydrops fetalis, and smaller lesions remaining asymptomatic and potentially regressing. The most common CLMs are congenital pulmonary adenomatoid malformations, bronchopulmonary sequestrations, congenital lobar emphysema, and bronchogenic cysts. All these lesions have clinically similar presentations when symptomatic, but pathophysiologic differences that must be considered when evaluating and treating. This article reviews the most common CLMs, their pathophysiology, clinical presentation, diagnostic considerations, and current literature on the controversies surrounding CLM management. [Pediatr Ann. 2019;48(4):e169-e174.].

Vanishing fetal lung malformations: Prenatal sonographic characteristics and postnatal outcomes

BACKGROUND/PURPOSE

The purpose of this study was to examine the natural history and outcomes of prenatally diagnosed lung masses that appear to undergo complete regression before birth.

METHODS

An IRB-approved retrospective review was performed on 100 consecutive fetuses with a congenital lung malformation at a single fetal center. Prenatal and postnatal imaging as well as outcomes of vanishing fetal masses was analyzed and compared to those with persistent fetal masses.

RESULTS

Seventeen lesions (17%) became sonographically undetectable at 35.3 ± 2.3 weeks gestation. Vanishing fetal masses were associated with microcystic disease (100% vs. 69%, p=0.005) and a low initial congenital pulmonary airway malformation volume ratio (CVR; 0.31 ± 0.35 vs. 0.70 ± 0.66, p=0.002) when compared to those with persistent fetal lesions. Based on postnatal CT imaging and pathology data, 10.3% of all fetal masses completely regressed. The positive predictive value and negative predictive value of prenatal ultrasound for detecting lung malformations in late gestation were 96% and 43%, respectively. All infants with vanishing fetal lesions were asymptomatic at birth and were more likely to be managed nonoperatively (75% vs. 22%, p<0.0001) when compared to infants with persistent fetal masses.

CONCLUSIONS

Vanishing lung lesions late in gestation are relatively common and are associated with a low CVR and microcystic disease.

Congenital cystic lesions of the lung

Congenital cystic lesions of the lung are present in 1 in 10,000-35,000 births and present as a spectrum of anomalies. Majority of these cystic lesions comprise congenital cystic adenomatoid malformations, pulmonary sequestrations, congenital lobar emphysema, and bronchogenic cysts. Most of these lesions are nowadays detected antenatally, however some will present either in the newborn or during later childhood. A review of the aetiology, classification, natural history, investigations, and treatment of congenital cystic lung lesions is discussed.

Recent advances in sonographic imaging of fetal thoracic structures

Recent ultrasonographic methods applied in the evaluation of fetal thoracic structures and anomalies are presented. Fetal lung volumetric assessment by 3D ultrasonography, analysis of the thoracic wall by 3D-rendered image and 3D skeletal-mode imaging, intrathoracic vessel evaluation by 3D power Doppler ultrasonography, analysis of heart anatomy and abnormalities by 4D spatiotemporal image correlation, identification of normal and abnormal intrathoracic almost isoechogenic structures by volume contrast imaging and evaluation of the heart and great vessels by 3 and 4D inverse mode will be reviewed.

Intraabdominal extrapulmonary sequestration diagnosed by color doppler ultrasound at 22 weeks' gestation

Intraabdominal extrapulmonary sequestration is seen very rarely. When a left suprarenal mass is detected in prenatal sonography, vascularization of the lesion should be evaluated with color Doppler sonography. We present a case of intraabdominal extrapulmonary sequestration that was diagnosed by color Doppler ultrasound at 22 weeks' gestation.

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.

Factors associated with partial and complete regression of fetal lung lesions

OBJECTIVE

A decrease in the volume of congenital pulmonary malformations (CPM) can be observed on prenatal ultrasonography, but the underlying mechanism for this phenomenon is unknown. Our objective was to identify factors associated with the prenatal reduction in size of cystic and/or hyperechoic lung lesions.

METHODS

This was a retrospective study of cases with a prenatal diagnosis of hyperechoic and/or cystic lung lesion. The extent of reduction in lesion size was calculated from ultrasound measurements. Clinical, ultrasound, radiological and histological data were tested for their relationship with prenatal CPM reduction.

RESULTS

In a 4-year period, 36 patients were referred with a cystic and/or hyperechoic fetal lung lesion diagnosed at a mean gestational age of 23.4 weeks. The lesions were cystic in 16 cases (44%), hyperechoic in 12 (33%) and both in eight (22%). The malformation was no longer visible before birth (apparent disappearance) in nine cases (25%), shrank by 18-90% in 15 (42%) and did not reduce in 12 (33%). Findings on postnatal computed tomography were always abnormal. Isolated hyperechoic lesions were significantly more likely to shrink in utero. The mean reductions were 79%, 35% and 19%, for isolated hyperechoic, cystic and mixed lesions, respectively (P=0.001). Only 8% of hyperechoic lesions demonstrated no volume reduction, as compared to 50% and 42% of cystic and mixed lesions, respectively (P=0.03). Greater gestational age at birth was also associated with a decrease in the incidence of malformations (P=0.02). In cases that underwent surgery, hyperechoic lesions were linked to a variety of pathological diagnoses, whereas cystic lesions were all described histologically as congenital cystic adenomatoid malformations.

CONCLUSIONS

Prenatal size reduction of fetal lung malformations is associated with isolated hyperechogenicity and greater gestational age at birth. This might result from the resumption of normal lung development after local disruption of lung growth.

Role of Doppler sonography in the diagnosis of pulmonary sequestration in an elderly patient: a case report

An 83-year-old man presented with an asymptomatic mass-like lesion in left lower lobe on chest radiograph and CT, with no change over the past 7 years. Because of discrepancy between clinical and radiological manifestations, chest color Doppler sonography was done and identified a large tortuous pulsating vessel with systemic arterial waveform flowing toward the probe and entering the lesion at its apex. Subsequent contrast-enhanced reconstructed CT scans of the chest with angiography confirmed the diagnosis of intralobar pulmonary sequestration.

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.

Three- and four-dimensional ultrasound: new methods for evaluating fetal thoracic anomalies

OBJECTIVE

To study three- (3D) and four-dimensional (4D) ultrasound applications for the evaluation of fetal thoracic anomalies.

METHODS

Volume datasets of 23 fetuses with thoracic anomalies were acquired with static 3D and cine 4D ultrasound, i.e. spatiotemporal image correlation (STIC) mode. The volumes were analyzed and displayed by multiplanar and tomographic ultrasound imaging (TUI) modes and static volume contrast imaging (VCI). Color Doppler was added to the volumes acquired, and various rendering modes were used to display the volume datasets.

RESULTS

The mean gestational age at evaluation was 22 (range, 14-34) weeks. The anomalies were identified as: diaphragmatic hernia (n = 5), lung dysplasia (n = 11), skeletal dysplasia with small thorax/thanatophoric dysplasia (n = 2), abnormal situs (n = 2), hydrothorax (n = 2) and esophageal atresia (n = 1). The TUI mode achieved optimal display of the thorax, thereby aiding the diagnosis of diaphragmatic hernia and lung dysplasia. In right diaphragmatic hernias, the VCI mode proved invaluable as it distinguished liver from lung tissue. High-definition color Doppler with glass-body rendering significantly contributed to the detection of abnormal vascularization in lung dysplasia. Maximal transparent mode with a transvaginal transducer provided accurate diagnosis of skeletal dysplasia in the first trimester. Situs abnormalities were best viewed with a minimal transparent mode, in which abnormal organs and positions of vessels were clearly identified. Pleuroamniotic shunt localization was monitored precisely by 3D in a fetus with hydrothorax, and inversion mode added important information regarding the size of an esophageal pouch in a fetus with esophageal atresia.

CONCLUSION

The 3D-4D technique is a novel, useful sonographic tool for evaluating the fetal thorax. It enhances precise diagnosis and provides better spatial visualization of the anomalies involved.

Three-dimensional ultrasound in prenatal diagnosis

PURPOSE OF REVIEW

Several technological advances have greatly improved three-dimensional sonography, which have improved acquisition and display capabilities. This review describes these technical changes as well as current applications of 3D sonography in prenatal diagnosis.

RECENT FINDINGS

Recently published papers have emphasized the potential of getting a precise 'any plane of choice' from a three-dimensional volume, as a new way of scanning, based on the off-line analysis of a volume dataset. Surface mode has been used to demonstrate malformations and genetic diseases. The maximum rendering mode, which highlights bones, has great potential for imaging the nasal bones and the frontal bones with the metopic suture. Organ volume can be measured, but the utility of this in clinical practice remains to be determined. Three-dimensional ultrasound needs to be standardized.

SUMMARY

Three-dimensional ultrasonography is the most rapidly developing technique in fetal imaging. New features will permit the transition from the era of 'sonography in two-dimensional planes' to 'volume ultrasound'.

[Fetal lung imaging]

Exponential improvements in imaging techniques over the last ten years, through patients' and physicians' wishes for less invasive fetal work-up, now allow us to better explore and understand fetal lung physiology during pregnancy. Diagnostic and prognostic consequences at stake are huge, especially for fetuses at risk of pulmonary hypoplasia. We will decline in three parts (normal lung, malformative lung and pulmonary hypoplasia), through a review of the literature and at the light of our experience, the potentialities and limitations of all imaging modalities (Ultrasound, Doppler, 3D, MRI). Then, we will dwell on future leads and the need for large-scale collaborative studies.

Neonatal pulmonary sequestration: clinical experience with transumbilical arterial embolization

Pulmonary sequestration (PS) is a rare congenital malformation of the lower respiratory tract. The exact natural course of PS is not well understood and there are no well-established treatment guidelines for antenatally diagnosed PS. The aim of this study was to describe clinical outcomes in neonates with PS and to evaluate the efficacy of transumbilical arterial embolization (TUE). From 1998 to 2006, total 30 neonatal cases were included. Serial antenatal ultrasound in 26 cases found 6 (23%) regressed lesions, all of which were demonstrated on postnatal chest CT. Six (20%) cases were classified as mixed-type (combined cystic) lesions. Surgery was performed early (during initial hospitalization) in two cases and lately (after the neonatal period) in four cases. TUE was performed for 17 (57%) cases of intrapulmonary PS. Follow-up images obtained a median of 19 months (range, 4-51) after TUE demonstrated complete (9, 53%), partial (5, 29%), and no (3, 18%) regression. The regression rate was significantly higher in solid-type lesions (13/13, 100%) than in mixed-type (1/4, 25%) (P = 0.006). Complications included transient hypertension (two cases, 12%), post-embolization fever (two cases, 12%) and migration of a microcoil (one case, 6%), without long-term morbidities. Natural courses could be observed in 10 cases of extralobar PS and regression was observed in 2 cases (20%) during a median follow-up of 12 months (range, 6-45). A well-designed comparative study is warranted to evaluate the long-term efficacy and safety of TUE.

Intrapericardial extralobar pulmonary sequestration presenting as a prenatal intrathoracic mass

An intrathoracic mass, which persisted during the remaining pregnancy, was first seen during routine ultrasound examination performed at 20 weeks gestation. After birth, the child was asymptomatic. Echocardiography showed the mass to be located intrapericardially. The mass was electively resected via sternotomy 3 weeks after the birth. Microscopic examination showed normal lung tissue surrounded by pleura corresponding to the diagnosis of extralobar pulmonary sequestration. To the authors' knowledge, this is the earliest described detection of such a lesion. Furthermore, this article reports the unique finding of a feeding vessel from the right pulmonary artery.

Prenatal diagnosis of pulmonary sequestration by ultrasound and magnetic resonance imaging

A 36-year-old multigravida, G2P1, underwent routine ultrasound scan at 22+1 weeks of gestation, which revealed a single normally growing fetus with left intrathoracic mass and left displacement of the cardiac apex. The left intrathoracic wedge-shaped hyperechogenic mass, measuring 32 x 25 mm in size, was situated at the lower portion of the left lung. A combination of color and power Doppler ultrasound allowed visualization of a vessel arising from the descending aorta, which supplied the mass. The diagnosis of extralobar pulmonary sequestration was made. Magnetic resonance imaging (MRI) was also performed and revealed a well-defined mass with homogeneous high-signal intensity when compared with normal lung tissue in the left upper lung field, which was compatible with pulmonary sequestration. The pulmonary mass was followed up by color and power Doppler every 2 weeks. The peak velocity of 11.85 cm/sec and the diameter of the feeding artery of 1.19 mm gradually decreased and disappeared 8 weeks later. The intrathoracic mass disappeared 10 weeks later at 32+1 gestational weeks. Repeat MRI also revealed spontaneous regression of the mass in favor of resorption of sequestration. The fetus was delivered at 38+1 gestational weeks. A male newborn weighing 2,520 g was spontaneously delivered with an Apgar score of 8 at 1 minute and 9 at 5 minutes. In our patient, it is suggested that progressive decreases in the peak velocity of the feeding vessel heralded the spontaneous regression of pulmonary sequestration not associated with hydrops/hydrothorax.

Three-Dimensional Echocardiography for Studies of the Fetal Heart: Present Status and Future Perspectives

Three-dimensional (3D) ultrasound of the fetal heart is increasingly being used in prenatal diagnosis. While very detailed fetal cardiac studies can be performed using the various 3D ultrasound modalities, their utility for screening for fetal heart disease is yet to be proven. With the emergence of even newer technologies such as quantification techniques and two-dimensional matrix arrays, further improvements are imminent.

Successful ultrasound-guided laser treatment of fetal hydrops caused by pulmonary sequestration

Microcystic or solid-looking fetal lung lesions associated with hydrops are associated with a high mortality rate. The most common of these lesions are microcystic congenital cystic adenomatoid malformations and pulmonary sequestrations (PS). Performing open fetal surgery by hysterotomy and lobectomy has, until now, been the only therapeutic option available following diagnosis of these lesions in the second trimester. Here we describe a new minimally invasive technique for the treatment of PS in the second trimester. Laser coagulation of the feeding systemic artery of the sequestration was performed under ultrasound guidance. The blood flow to the lung tumor was successfully arrested and hydrops reversed. The child was born at term and, at the time of writing, was alive and well at 2 years of age. Large PS with hydrops can be treated successfully by ultrasound-guided minimally invasive laser surgery. It is therefore important to utilize color Doppler ultrasound imaging for identification of a systemic feeding blood vessel in solid fetal lung tumors. Published by John Wiley & Sons, Ltd.

Prenatal intervention for isolated congenital diaphragmatic hernia

PURPOSE OF REVIEW

We aim to review the recent literature regarding early prenatal prediction of outcome in babies diagnosed with isolated congenital diaphragmatic hernia, as well as results of fetal therapy for this condition.

RECENT FINDINGS

Current survival rates in population-based studies are around 55-70%. Highly specialized centers report 80% and more, but discount the hidden mortality, mainly in the antenatal period. Fetuses presenting with liver herniation and a lung-to-head ratio of less than 1.0 measured in midgestation have a poor prognosis. Other volumetric techniques are being evaluated for use in midtrimester. Recently, a randomized trial failed to show benefit from prenatal therapy, but lacked power to document the potential advantage of prenatal therapy in severe cases. We proposed percutaneous fetal endoluminal tracheal occlusion with a balloon at 26-28 weeks through a 3.3 mm incision. In severe cases, fetal endoluminal tracheal occlusion increased lung size as well as survival, with an early (7 day) survival, late neonatal (28 day) survival and survival at discharge of 75, 58 and 50%, respectively, comparing favorably with 9% in contemporary controls. Airways can be restored prior to birth improving neonatal survival (83.3% compared with 33.3%). The procedure carries a risk for preterm prelabour rupture of the fetal membranes, although that may decrease with experience.

SUMMARY

Fetuses with severe congenital diaphragmatic hernia can be identified in the second trimester. Fetal endoluminal tracheal occlusion can be considered as a minimally invasive fetal therapy, improving outcome in such highly selected cases.

Prenatal detection and evaluation of an extralobar pulmonary sequestration in the posterior mediastinum

Extralobar pulmonary sequestration (EPS) is a rare developmental anomaly with aberrant nonfunctioning parenchymal tissue, associated with an increased risk of perinatal morbidity and, rarely, mortality owing to possible neonatal respiratory distress. In most cases supernumerary lobes are detected as isolated intra- or extrapleural lesions with independent systemic arterial blood supply. We report an atypical case of prenatal detection and perinatal outcome of a mediastinal EPS.