Prenatal diagnosis and outcome of fetal lung masses

Aim

The purpose of this study is to evaluate the accuracy of prenatal diagnostic features, particularly congenital cystic adenomatoid malformation volume ratio (CVR), in predicting outcomes for fetuses with lung masses.

Methods

The records and imaging features of all fetuses referred to the Texas Children's Fetal Center with a fetal lung mass between July 2001 and May 2010 were reviewed retrospectively. Data collected included gestational age (GA) at diagnosis, fetal magnetic resonance imaging findings, CVR, mass size, nature of fetal treatment, surgical findings, pathology, and outcome. Data were analyzed for predicting development of hydrops or the need for fetal therapy using receiver operating characteristic curves.

Results

Of 82 fetuses (41 male) evaluated for a lung mass, 53 (65%) were left-sided (1 bilateral), and the mean (SD) GA at diagnosis was 21.5 (4.3) weeks. Seventy-three fetuses underwent fetal magnetic resonance imaging at a mean (SD) GA of 26.1 (4.6) weeks. Thirteen fetuses (16%) had fetal treatment. Four fetuses with hydrops underwent open fetal surgical resection, and 3 survived. Six fetuses with large lung masses and persistent mediastinal compression near term underwent ex-utero intrapartum therapy-to-resection procedures, and 3 fetuses with hydrops underwent serial thoracentesis. Congenital cystic adenomatoid malformation volume ratio correlated strongly with the development of hydrops and the need for fetal therapy with an area under the receiver operating characteristic curve of 0.96 (P < .0001) and 0.88 (P < .0001), respectively. Of 18 fetuses with a CVR greater than 2.0 compared with 2 (3%) of 60 with a CVR of 2.0 or less, 10 (56%) required fetal intervention (P < .0001).

Conclusion

Congenital cystic adenomatoid malformation volume ratio correlates strongly with the development of fetal hydrops and the need for fetal intervention. A threshold value of 2.0 yields the most powerful statistical results.     

Outcomes of fetal intervention for primary hydrothorax

Objective

Primary hydrothorax is a rare congenital anomaly with outcomes ranging from spontaneous resolution to fetal demise. We reviewed our experience with fetuses diagnosed with primary hydrothorax to evaluate prenatal management strategies.

Methods

We reviewed the records of patients evaluated for fetal pleural effusions at our Fetal Treatment Center between 1996 and 2013. To define fetuses with primary hydrothorax, we excluded those with structural or genetic anomalies, diffuse lymphangiectasia, immune hydrops, and monochorionic diamniotic twin gestations.

Results

We identified 31 fetuses with primary hydrothorax, of whom 24 had hydrops. Hydropic fetuses were more likely to present with bilateral effusions. Of all fetuses with primary hydrothorax, 21 had fetal interventions. Survival without hydrops was 7/7 (100%), whereas survival with hydrops depended on whether or not the patient had fetal intervention: 12/19 (63%) with intervention and 1/5 (20%) without intervention. Premature delivery was common (44%) among those who had fetal intervention.

Conclusions

Fetal intervention for primary hydrothorax may lead to resolution of hydrops, but preterm birth and neonatal demise still occur. Understanding the pathophysiology of hydrops may provide insights into further prenatal management strategies, including targeted therapies to prevent preterm labor.     

Fetal MRI lung volumes are predictive of perinatal outcomes in fetuses with congenital lung masses

Purpose

The purpose of this study was to evaluate fetal magnetic resonance imaging (MRI) as a modality for predicting perinatal outcomes and lung-related morbidity in fetuses with congenital lung masses (CLM).

Methods

The records of all patients treated for CLM from 2002 to 2012 were reviewed retrospectively. Fetal MRI-derived lung mass volume ratio (LMVR), observed/expected normal fetal lung volume (O/E-NFLV), and lesion-to-lung volume ratio (LLV) were calculated. Multivariate regression and receiver operating characteristic analyses were applied to determine the predictive accuracy of prenatal imaging.

Results

Of 128 fetuses with CLM, 93% (n = 118) survived. MRI data were available for 113 fetuses. In early gestation (< 26 weeks), MRI measurements of LMVR and LLV correlated with risk of fetal hydrops, mortality, and/or need for fetal intervention. In later gestation (> 26 weeks), LMVR, LLV, and O/E-NFLV correlated with neonatal respiratory distress, intubation, NICU admission and need for neonatal surgery. On multivariate regression, LMVR was the strongest predictor for development of fetal hydrops (OR: 6.97, 1.58–30.84; p = 0.01) and neonatal respiratory distress (OR: 12.38, 3.52–43.61; p ≤ 0.001). An LMVR > 2.0 predicted worse perinatal outcome with 83% sensitivity and 99% specificity (AUC = 0.94; p < 0.001).

Conclusion

Fetal MRI volumetric measurements of lung masses and residual normal lung are predictive of perinatal outcomes in fetuses with CLM. These data may assist in perinatal risk stratification, counseling, and resource utilization.     

Management of fetal mediastinal teratoma

Background/Purpose

Mediastinal teratomas are rare congenital germ cell tumors that prenatally can compress mediastinal structures and cause hydrops. Two possible presentations of massive fetal mediastinal teratoma include hydrops leading to fetal demise, or fetal esophageal and airway compression causing late-gestation polyhydramnios and preterm labor. The authors present 2 cases of fetal mediastinal teratoma that illustrate successful strategies for either of these presentations.

Methods

A 37-year-old woman carrying a fetus with a mediastinal mass and secondary hydrops at 23 weeks of gestation underwent in utero resection of the mass. Delivery was by cesarean delivery at 25 weeks because of preterm labor. A 24-year-old mother carrying a fetus with a mediastinal mass and severe polyhydramnios at 36 weeks of gestation underwent an ex utero intrapartum therapy procedure for establishment of an airway and tumor resection on uteroplacental support.

Results

These strategies resulted in physiologic improvement in the first case and controlled resection and resuscitation in the second. The first patient had significant sequelae of prematurity including bronchopulmonary dysplasia but is currently well at 9 months of age. The second patient is well at 1 year of age.

Conclusions

Massive fetal mediastinal teratoma can result in fetal or neonatal mortality by a variety of mechanisms. Optimal prenatal and perinatal management is required to salvage fetuses compromised by this lesion.     

Characteristics of congenital cystic adenomatoid malformations associated with nonimmune hydrops and outcome

Background/Purpose

In fetuses with congenital cystic adenomatoid malformations of the lung (CCAMs), hydrops fetalis and large masses are associated with poor outcomes. This study attempts to (1) determine sonographic features (in addition to large size) that correlate with hydrops and (2) characterize the features that correlate with outcome among hydropic fetuses.

Method

Charts and sonograms of fetuses with large, unilateral CCAMs were retrospectively reviewed. Mass features evaluated included laterality, macrocystic/microcystic, cystic/solid predominance, degree of mediastinal shift, retrocardiac component, diaphragm eversion, polyhydramnios, and mass-thorax ratio (MTR). Features of hydrops included degree of ascites, scalp and integumentary edema, pleural/pericardial effusion, and placentomegaly.

Results

Thirty-six fetuses with large CCAMs were studied: 27 with and 9 without hydrops. Three sonographic features were significantly associated with hydrops: MTR of at least 0.56, cystic predominance of mass, and eversion of hemidiaphragm. Of 27 fetuses with hydrops, 10 (37%) demonstrated all 3 features compared with none in those without hydrops (P = .04). All 9 nonhydropic fetuses were expectantly managed, and 100% survived. In the hydropic group, none of the expectantly managed fetuses survived, and 10 (43%) of the 21 fetuses who underwent fetal intervention survived.

Conclusion

Three features of large CCAMs were significantly associated with hydrops: MTR, cystic predominance, and diaphragm eversion. Identification of these features will allow clinicians to accurately predict which fetuses may warrant closer follow-up and possible treatment.     

Prenatal steroids for microcystic congenital cystic adenomatoid malformations

Objective

The purpose of this study is to evaluate the effect of prenatal steroid treatment in fetuses with sonographically diagnosed congenital cystic adenomatoid malformations (CCAMs).

Methods

This was an institutional review board-approved retrospective review of 372 patients referred to the University of California, San Francisco (UCSF), for fetal CCAM. Inclusion criteria were (1) a predominately microcystic CCAM lesion sonographically diagnosed at our institution, (2) maternal administration of a single course of prenatal corticosteroids (betamethasone), and (3) no fetal surgery. CCAM volume-to-head ratio (CVR), presence of hydrops, mediastinal shift, and diaphragm eversion were assessed before and after administration of betamethasone. The primary end points were survival to birth and neonatal discharge.

Results

Sixteen patients with predominantly microcystic CCAMs were treated with prenatal steroids. Three were excluded because of lack of follow-up information. All remaining fetuses (13/13) survived to delivery and 11/13 (84.6%) survived to neonatal discharge. At the time of steroid administration, all patients had CVR greater than 1.6, and 9 (69.2%) also had nonimmune hydrops fetalis. After a course of steroids, CVR decreased in 8 (61.5%) of the 13 patients, and hydrops resolved in 7 (77.8%) of the 9 patients with hydrops. The 2 patients whose hydrops did not resolve with steroid treatment did not survive to discharge.

Conclusion

In high-risk fetal patients with predominantly microcystic CCAM lesions, betamethasone is an effective treatment. This series is a pilot study for a prospective randomized trial comparing treatment of CCAM with betamethasone to placebo.     

Comparison of inguinal hernia and asymptomatic patent processus vaginalis in term and preterm infants

Introduction

The aim of this study was to evaluate the characteristics of inguinal hernia (IH) and patent processus vaginalis (PPV) in term and preterm infants less than the age of 6 months.

Method

Between January 2004 and December 2012, 246 term and 165 preterm infants underwent laparoscopic herniorrhaphy within the first 6 months of life. Preoperative clinical presentation and intraoperative anatomical findings during the laparoscopic procedure were evaluated. Additionally, initial side of hernia, laterality of IH and PPV were analyzed in term and preterm infants.

Results

In the group of term infants, most infants presented with a primary right-sided IH (58.5%) versus 17.9% left-sided and 23.6% bilateral IH. Babies with primary unilateral IH were found to have a contralateral PPV in 41.0% of cases. A difference between left-sided PPV and right-sided PPV could not be identified.In the group of preterm infants, initial bilateral presentation was predominant (38.8%) versus right-sided (30.3%) and left-sided IH (30.9%). Infants with primary unilateral IH were found to have a contralateral PPV in 56.4%. We identified a slight difference between left-sided PPV (54.0%) and right-sided PPV (58.8%).

Conclusion

IH is predominantly right sided in term infants, whereas preterm infants mostly present with bilateral IH. The incidence of PPV was found to be significantly higher in the preterm group. Regarding the incidence of a contralateral PPV in term and preterm infants, no difference between initial left-sided and right-sided IH could be identified between both groups.     

High-risk fetal congenital pulmonary airway malformations have a variable response to steroids

Background/Purpose

Anecdotal reports suggest that maternal steroids may arrest the growth of congenital pulmonary airway malformations (CPAMs), preventing or reversing hydrops. We reviewed our experience with CPAMs to determine the fetal response to steroid therapy.

Methods

This study is a retrospective review of all fetal CPAMs from 2004 to 2008. Fetuses with high-risk CPAMs that received at least one course of steroids were identified. Fetal magnetic resonance imaging and ultrasound data were used to classify the CPAMs, identify hydrops fetalis and follow the fetuses poststeroid dosing.

Results

Forty-four fetuses with CPAM were identified. Fifteen patients were found to have received at least one course of steroids. Thirteen were hydropic and 2 were nonhydropic. Seven of the 13 hydropic fetuses (54%) showed an initial response to steroid administration, whereas the 2 nonhydropic high-risk fetuses progressed to birth without developing hydrops. Seven of the 15 patients, however, resulted in fetal demise or early postnatal death, giving a survival rate of 53%.

Conclusions

High-risk CPAMs have a variable response to steroids. This variable response demonstrates the need for a placebo-controlled randomized study to more accurately determine the effect of steroids on hydrops and CPAM growth rates. Repeated steroid courses may not be helpful, and progression in CPAM volume to head circumference ratio (CVR) or hydrops should prompt open fetal surgery to prevent irreversible fetal insult.     

Fetal intervention for mass lesions and hydrops improves outcome: a 15-year experience

Purpose

The natural history of certain prenatally diagnosed masses is well known. Large thoracic mass lesions can evolve one of 2 ways, either to regress and cause minimal morbidity, or to progress and enlarge, often resulting in hydropic changes in the fetus. This nonimmune hydrops carries a dismal prognosis, with nearly all fetuses expiring before or shortly after birth. However, hydrops associated with fetal mass lesions can be halted and even reversed with fetal intervention and treatment of the underlying defect. We examined our patients with fetal mass lesions to evaluate survival after intervention.

Methods

Institutional approval was obtained by the Committee on Human Research. A retrospective review was performed of 294 fetuses evaluated over 15 years with large mass lesions. All patients were evaluated for evidence of fetal hydrops using ultrasound criteria. Patients were divided according to type of intervention. Primary outcome measure was 30-day survival after birth.

Results

(1)

Patients without fetal hydrops did not undergo fetal intervention and survived to 30 days after birth (167/172, 97%).

(2)

Patients with fetal mass lesions that developed hydrops fared poorly with no intervention (1/33 survival, 3%), whereas fetuses undergoing prenatal intervention fared much better (15/30 open, 50%; 3/10 percutaneous, 30%).

(3)

Four patients with hydropic congenital cystic adenomatoid malformation (n = 3) or pulmonary sequestration (n = 1) received steroids in preparation for surgery but underwent no intervention, and the patients survived the neonatal period.

Conclusion

Fetuses with prenatal diagnoses of masses not associated with hydrops have excellent prognosis with survival higher than 95%. Nonimmune hydrops associated with prenatal diagnosis of a fetal mass is a devastating complication with less than 5% survival. Open resection of a mass causing hydrops resulted in 50% survival, with reversal of hydrops in a group with near-uniform fatality. Further investigation is warranted regarding the use of minimally invasive prenatal therapies including steroid administration for hydropic fetuses.     

Congenital diaphragmatic hernia and hydrops: a lethal association?

Background/Purpose: Nonimmune hydrops in the fetus is a finding that often portends death. The association and prognosis of fetuses with congenital diaphragmatic hernia (CDH) and hydrops is not known. Methods: A retrospective review of all prenatally diagnosed cases and referrals of CDH was performed. Variables analyzed included gestational age at diagnosis and delivery, side of hernia, presence of associated anomalies and hydrops, and neonatal outcome. Results: Since 1993, 474 prenatal referrals for CDH have been made. One hundred seventy-five were evaluated; 15 fetuses had hydrops (9%). Five patients had CDH, hydrops, and associated lethal anomalies. In the remaining 10 patients, 6 of the diaphragmatic defects were right-sided and 4 were left-sided. All except one had a major portion of the liver herniated into the chest. Six fetuses had prenatal intervention. Five neonates died shortly after birth. There were 5 long-term survivors; all received prenatal intervention. Conclusions: The association of CDH and hydrops is rare but often results in fatality. Hydrops appears to be associated with liver in the hernia, right-sided lesions, and lethal anomalies. Fetal intervention can be performed successfully in patients with CDH and hydrops, and may improve long-term survival rate in this group.     

Outcome predictors for infants with cystic lung disease

Background/purpose

This study aimed at identifying characteristic features indicating congenital cystic adenomatoid malformation of the lung (CCAM) and evaluating the outcome predictors to identify prenatally subgroups of fetuses with significantly different probabilities of mortality or severe respiratory difficulty.

Methods

Twenty-eight neonates who had undergone antenatal evaluation for cystic lung disease (CLD) were reviewed retrospectively. The patients were divided into 3 groups according to the severity of their clinical course; mild (n = 7), moderate (n = 13), and severe (n = 8). Ultrasonographic findings in the fetus and their pulmonary lesion were evaluated. The normal lung to thorax transverse area ratio (L/T) was measured by ultrasonography.

Results

High echogenicity of the lesion throughout pregnancy and polyhydramnios were frequently seen in CCAM. All of the patients with other CLD showed isoechogenicity at the end of pregnancy. All patients in the severe group had both polyhydramnios and fetal hydrops. L/T was increased in mild and moderate groups, whereas no patient in the severe group had an increase in L/T at the final measurement. Each value of final L/T in the severe group was less than 0.25.

Conclusions

The subgroup of fetuses with an increased probability of mortality or severe respiratory difficulty could be predicted from the combination of polyhydramnios, fetal hydrops, and a final L/T value of less than 0.25.     

The ex utero intrapartum therapy procedure for high-risk fetal lung lesions

Background

Indications for the ex utero intrapartum therapy (EXIT) procedure have expanded to include any fetal anomaly in which resuscitation of the neonate may be compromised.

Methods

We reviewed the medical records of 9 patients after resection of lung lesions during the EXIT procedure.

Results

The mean gestational age at EXIT procedure was 35.4 weeks. All lung masses maintained large sizes late into gestation with mean mass volume/head circumference ratio of 2.5 at presentation and 2.2 at EXIT. Seven of 9 fetuses demonstrated hydropic changes (n = 6) and/or polyhydramnios (n = 5), and underwent prenatal intervention including thoracentesis, thoracoamniotic shunt placement, amnioreduction, and/or betamethasone administration. Overall survival after EXIT for lung mass resection was 89%. The average time on placental bypass was 65 minutes. Postnatal complications included reoperation for air leak (n = 1), reoperation for bleeding (n = 1), and death from sepsis and prematurity (n = 1). Venoarterial extracorporeal membrane oxygenation was used in 4 neonates for persistent pulmonary hypertension. Maternal prenatal complications included polyhydramnios (n = 5), preterm labor (n = 4), and chorioamnionitis (n = 1). One mother required perioperative blood transfusion.

Conclusion

The EXIT procedure allows for controlled resection of large fetal lung lesions at delivery, avoiding acute respiratory decompensation related to mediastinal shift, air trapping, and compression of normal lung.     

Severe pulmonary hypoplasia associated with giant cervical teratomas

Background

The use of the ex utero intrapartum treatment (EXIT) procedure has salvaged many fetuses with giant neck masses. Despite an adequate airway, a subset of these patients die from an inability to achieve adequate gas exchange.

Methods

We reviewed our experience with the EXIT procedure from 1996 to 2004. The EXIT was used to deliver 23 fetuses with giant neck masses.

Results

Three fetuses with giant cervical teratomas died of severe pulmonary hypoplasia. On postmortem, these patients had severe airway distortion by the mass. The carina was retracted superiorly to the first or second rib resulting in compression of the lungs in the apices of the chest and pulmonary hypoplasia. Hypoplasia was reflected in the lung weights of 24 vs 38 g and 17 vs 34 g for age-matched normal lung.

Conclusions

Unsuspected obstructive fetal neck masses can be fatal because of an inability to secure an airway. Prenatal ultrasonography can identify fetuses at risk, allowing the fetus to be salvaged using the EXIT procedure. Despite obtaining airway control, a subset of these patients will die because of pulmonary hypoplasia. When counseling patients with large cervical masses it is important to discuss potential pulmonary hypoplasia in these patients.     

Feasibility of magnetic resonance spectroscopy for evaluating fetal lung maturity

Background/Purpose

Amniocentesis is an invasive procedure with inherent risks. Magnetic resonance (MR) spectroscopy is a safe noninvasive way of measuring levels of choline-containing compounds (including surfactant) and other metabolites. The purpose of this study was to test the feasibility of assessing fetal lung maturity in vivo and ex vivo using MR spectroscopy to determine differences in amniotic fluid choline concentrations between the second and third trimesters.

Methods

Magnetic resonance spectroscopy was performed on ex vivo samples of amniotic fluid from second- and third-trimester fetuses. In vivo MR spectroscopy was performed on amniotic fluid and fetal lungs in third-trimester fetuses. Spectral acquisition and analysis were performed by an attending radiologist in conjunction with an MR spectroscopist.

Results

Choline-containing compounds were observed from 3.20 to 3.25 ppm. Comparison of spectra from second- and third-trimester amniocentesis revealed a trend toward increased choline at later gestational ages. Spectra from amniotic fluid and lungs of a third-trimester fetus showed that choline can be detected in the in vivo setting.

Conclusions

Magnetic resonance spectroscopy is a safe noninvasive procedure that enables measurement of choline-containing compounds in fetal lung and amniotic fluid. Magnetic resonance spectroscopy shows a trend toward an increased quantity of choline in third- vs second-trimester amniocentesis.     

Predicting perinatal outcome in isolated congenital diaphragmatic hernia using fetal pulmonary artery diameters

Objective

The aim of the study was to evaluate the potential of fetal pulmonary artery (PA) diameters to predict perinatal death and pulmonary arterial hypertension (PAH) in congenital diaphragmatic hernia (CDH).

Study Design

In this prospective observational study, observed PA (main, right, and left) diameters were measured at the level of the 3 vessels in 21 fetuses with isolated CDH and in 85 controls at 22 to 36 weeks. The observed/expected (o/e) diameters of the main, contralateral, and ipsilateral PAs were calculated by comparing these measurements with reference values obtained in our previous study and correlated with perinatal death and postnatal PAH.

Results

The o/e PA diameters were significantly reduced in fetuses with CDH compared to controls (P < .001) and in fetuses with CDH who died (P < .050). However, there was no significant association between PA diameters and PAH (P ≥ .050).

Conclusions

The PA diameters might be useful to predict perinatal death in isolated CDH but not postnatal PAH, suggesting that PA diameters are probably related to the severity of pulmonary hypoplasia.     

Predicting the severity of congenital high airway obstruction syndrome

Background

Congenital high airway obstruction syndrome (CHAOS) is caused by complete or near-complete obstruction of the fetal airway. Obstruction sets in motion a sequence of events that can ultimately lead to fetal demise. However, on rare occasions in utero airway decompression occurs, reversing syndromic findings and improving the prognosis. In our relatively large series of CHAOS patients, we have observed a spectrum of clinical severity. The aim of this study was to identify the prenatal characteristics of CHAOS predictive of a milder postnatal course.

Methods

The medical charts of all fetuses observed at our institution with the diagnosis of CHAOS were reviewed for radiologic findings, delivery information, perinatal course, autopsy or discharge report, and long-term follow-up.

Results

Between 1996 and 2008, 12 fetuses with CHAOS were identified. Four fetuses had no evidence of hydrops on initial imaging. Of the 8 fetuses displaying hydrops, 3 were terminated, 2 died in utero, and 1 with multiple anomalies died at birth. Six fetuses were delivered via the ex utero intrapartum therapy procedure for attempted salvage, and 5 of the 6 survived the neonatal period including all 4 fetuses without hydrops. Serial prenatal imaging demonstrated less severe signs of CHAOS in 3 fetuses, and in 2 of them, direct laryngoscopy revealed a tiny opening in the airway. All 3 fetuses that showed improvement on serial imaging survived the neonatal period and were discharged home by 2-10 weeks of age.

Conclusions

Although the natural history of CHAOS is variable, trends in prenatal ultrasound findings are highly predictive of postnatal outcome and are a valuable guide to prenatal counseling.     

Innovative,simplified orthotopic lung transplantation in rats

Background

Various techniques of orthotopic single lung transplantation in rats have been reported; however, their widespread use has been limited owing to the complexity of the procedure. We report a novel microsurgical lung transplantation model in rats with a high survival rate that can be performed by one surgeon alone.

Methods

A total of 90 left lung allografts were transplanted from Fischer to Wistar Kyoto rats. We developed a triple axis precision system to place and stabilize the vascular clips intrathoracically to clamp the bronchovascular structures, thereby avoiding interference with the heart and contralateral lung movement. A single-suture bronchial anastomosis technique and proximal cuffing approach for vascular anastomosis was used, rendering surgical assistance unnecessary.

Results

In our recent series, both short-term (12 h) and long-term (21 d) survival was 100%. The lungs showed excellent perfusion and ventilation immediately on transplantation. Blood gas samples drawn from the left pulmonary vein and the histologic sections revealed excellent graft function. The donor operation lasted 20 ± 2 min, donor left lung dissection required 20 ± 2 min, and implantation required 90 ± 5 min.

Conclusions

The present innovative method of left orthotopic single lung transplantation can be performed by one experienced surgeon alone, with excellent results and a high degree of reproducibility.     

Fetoscopic approach to amniotic band syndrome

Background

Amniotic band syndrome (ABS) is an uncommon complication of pregnancy that can result in fetal demise.

Methods

We present our experience with fetoscopic amniotic band release.

Results

Five patients underwent fetoscopic amniotic band release for preoperatively diagnosed ABS involving at least one extremity. Four of five patients were found to have involvement of the umbilical cord at the time of fetoscopy. One of these four did not have the band released and underwent fetal demise at 24 weeks. All four survivors had good functional outcomes of affected limbs. Two patients developed membrane separation and had preterm deliveries at 32 weeks gestation whereas the other two carried to term. No maternal complications were noted.

Conclusions

Fetoscopic amniotic band release is safe. Umbilical cord involvement is difficult to assess preoperatively, but when it is present should be treated to reduce the risk of fetal demise.     

Long-term outcome in patients with prenatally diagnosed cystic lung disease: special reference to ventilation and perfusion scan in the affected lung

Background/Purpose

The natural history of cystic lung disease (CLD) such as congenital cystic adenomatoid malformation (CCAM) and pulmonary sequestration has been altered by the advent of prenatal diagnosis. Although recent advances including fetal therapy have gradually improved outcome, the long-term course and the function of the residual lung have not been well clarified.

Methods

Twenty-two patients with CLD who had been prenatally diagnosed and treated between 1990 and 2004 were reviewed. The clinical outcome and growth measurements were established, and, where possible, all infants underwent ventilation and perfusion lung scan.

Results

Mediastinal shift was present in 14 fetuses. Fetal hydrops was present in 5 fetuses. Antenatal intervention was performed for hydrops in 2 fetuses (cyst-amniotic shunt and aspiration). Twenty-one infants underwent appropriate excisional surgery. Final diagnosis included CCAM (n = 12) and pulmonary sequestration (n = 7). No late death was observed. Common complications were failure to thrive (n = 5), frequent respiratory tract infection (n = 4), and asthmatic attack (n = 4). A significant decrease in lung ventilation and perfusion on the affected side was observed in patients with hydrops, lobectomy, and CCAM.

Conclusion

Long-term follow-up including respiratory care and growth assessment should be performed in prenatally diagnosed patients with CLD, especially those who present with hydrops.     

Postnatal lung mechanics, lung composition, and surfactant synthesis after tracheal occlusion vs prenatal intrapulmonary instillation of perfluorocarbon in fetal rabbits

Background/Purpose

Fetal tracheal occlusion (TO) accelerates lung growth but decreases surfactant production. We have previously shown that instillation of perfluorooctylbromide (PFOB) into fetal rabbit lungs leads to lung growth similar to TO. This study compares neonatal lung mechanics and surfactant production after prenatal intrapulmonary PFOB instillation vs TO.

Methods

In each of 18 pregnant rabbits on gestational day 27, sets of 4 fetuses underwent either (1) intrapulmonary instillation of 1 mL PFOB, (2) TO, (3) instillation of 1 mL 0.9% NaCl (saline), and (4) hysteroamniotomy without fetal manipulation (control). Fetuses were born by cesarean delivery after 48 hours. Fetuses of 12 rabbits were mechanically ventilated for 15 minutes to evaluate lung compliance and airway resistance. Pulmonary surfactant protein B (SP-B) was quantified by immunohistochemistry in fetuses of the remaining 6 rabbits.

Results

Compliance was decreased in the TO group after cesarean delivery (0.33 ± 0.13 mL/cm H₂O) compared with PFOB (0.59 ± 0.12 mL/cm H₂O), saline (0.50 ± 0.12 mL/cm H₂O), and control (0.52 ± 0.10 mL/cm H₂O) fetuses. Mean fetal lung to body weight ratio was higher in TO and PFOB fetuses compared with saline and control. Higher water content and lower numbers of surfactant protein B-positive cells were found in the TO-treated fetuses.

Conclusions

Both prenatal intrapulmonary instillation of PFOB and TO accelerate lung growth, but TO is associated with decreased postnatal lung compliance, possibly influenced by decreased surfactant production and increased fluid retention. Conversely, instillation of PFOB preserved lung compliance and surfactant synthesis.