Large fetal congenital cystic adenomatoid malformations: growth trends and patient survival

Purpose

The prognosis for fetuses with large congenital cystic adenomatoid malformations (CCAMs) remains uncertain. This study examined the natural history of large fetal CCAMs managed expectantly at a major referral center.

Methods

A 5-year retrospective review was conducted on fetuses diagnosed with a thoracic lesion (n = 59). Large CCAMs were identified on prenatal imaging and followed longitudinally. Perinatal outcomes were assessed.

Results

Twelve (20.3%) fetuses had large CCAMs in the absence of other congenital anomalies. Peak CCAM size occurred at 25.3 ± 3.6 weeks' gestation. Serial magnetic resonance volumetry demonstrated a trend toward decreasing CCAM mass volume relative to thoracic cavity volume over time. Overall, 6 patients, including 3 with signs of early hydrops, showed a marked regression of their lesions relative to estimated fetal weight. Five fetuses required an emergent intervention postnatally, including extracorporeal membrane oxygenation support (n = 1), cyst aspiration (n = 1), and lung resection (n = 5). Overall survival was 75%, with severe hydrops before 30 weeks seen in all 3 deaths.

Conclusion

Large fetal CCAMs tend to peak in size at 25 weeks' gestation and are characterized by in utero diminution relative to overall fetal growth. The prognosis for most fetuses with large CCAMs remains quite favorable under careful perinatal management.     

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.     

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.     

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.     

Prenatal growth characteristics and pre/postnatal management of bronchopulmonary sequestrations

Purpose

The prenatal natural history of intralobar and extralobar bronchopulmonary sequestrations (BPSs), including lesion growth patterns and need for prenatal intervention, have not been fully characterized. We review our series of BPSs to determine their natural history and outcomes in the context of the need for prenatal intervention.

Postnatal spontaneous resolution of congenital cystic adenomatoid malformations

Purpose

Although antenatal resolution of congenital cystic adenomatoid malformations (CCAMs) is well documented, complete spontaneous postnatal resolution is rare, its existence even questioned by some.

Methods

All cases of antenatally diagnosed CCAMs over 7 years were retrospectively reviewed. Inclusion criteria were the following: (1) antenatal diagnosis of CCAM, (2) persistence on postnatal imaging, and (3) subsequent spontaneous resolution on postnatal imaging.

Results

Of 56 antenatally diagnosed CCAMs, 2 patients were identified. Both had macrocystic lesions. In case 1, the CCAM that filled the hemithorax on antenatal ultrasound was smaller on postnatal chest radiograph and disappeared by age 37 months on computed tomography. Case 2 had significant reduction of the CCAM at birth (persistence of the lesion on initial radiographs and ultrasound was documented). By 5 months, the lesion was not evident on computed tomography. Neither case was associated with symptoms, polyhydramnios, hydrops, or other abnormalities.

Conclusions

In patients with an antenatal diagnosis of CCAM, spontaneous resolution may occur postnatally in 4% of cases. Significant reduction in CCAM size may portend possible disappearance and therefore warrants an observational period before resection.     

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.     

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.     

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.     

Is congenital cystic adenomatoid malformation a premalignant lesion for pleuropulmonary blastoma?

Background

The relationship between congenital cystic adenomatoid malformation (CCAM) and pleuropulmonary blastoma (PPB), whether causal, correlational, or coincidental, remains controversial. There is a lack of consensus as to the optimal treatment of patients with asymptomatic CCAM.

Method

We reviewed all cases of CCAM and PPB seen at our institution from 1999 to 2008. Institutional Research Ethics Board approval was obtained. The incidence of CCAM and PPB, respectively, was calculated based on birth numbers during the study period.

Results

Seventy-four CCAMs were resected over the study period in 129 children diagnosed with CCAM. Five PPBs were diagnosed during the study period. Three of the 5 PPB cases were initially diagnosed as CCAMs. These PPBs were not clinically or radiologically distinguishable from CCAMs. In our referral area, the incidence of CCAM was 1 in 12,000; and the incidence of PPB was 1 in 250,000 live births. The mortality rate for PPB in this cohort was 20%.

Conclusion

Asymptomatic cystic lung malformations represent a therapeutic dilemma. In this cohort, the incidence of PPB among apparently benign lung lesions was 4%. No clinical or radiological markers differentiated benign CCAMs from PPBs. Our experience provides further justification for resection of all CCAMs. This should be discussed with parents until CCAMs and PPBs can be clearly distinguished preoperatively.     

Current outcome of antenally diagnosed cystic lung disease

Background/purpose

The natural history of parenchymal lung lesions such as congenital cystic adenomatoid malformation (CCAM) and pulmonary sequestration (PS) has been altered by the advent of antenatal ultrasonography. Initial reports were characterized by a high (about 30%) incidence of adverse features (eg, hydrops) and a poor outcome and did not accord with our recent experience. The authors have reviewed the outcome of fetuses that had been diagnosed in a large tertiary referral fetal medicine unit with the aim of delineating current experience. The term cystic lung disease was used throughout to avoid unjustifiable histologic precision.

Methods

The scans of all fetuses that had been diagnosed with cystic lung disease between January 1995 and July 2001 were reviewed. The outcome of each pregnancy was established, and, where possible, all infants underwent appropriate investigations, including thoracic computed tomography (CT) scans.

Results

Sixty-seven fetuses had a cystic lung abnormality diagnosed from January 1995 to July 2001. The median (range) age at diagnosis was 21 (19 to 28) weeks. The lesion was right sided in 29 (43%), left in 36 (54%), and bilateral in 2 (3%); it was characterized as dominantly macrocystic in 27 (40%), microcystic in 35 (52%), and mixed in 5 (8%). Mediastinal shift was present in 30 fetuses (45%). Severe signs of fetal distress (eg, hydrops) were present in 5 fetuses (7%). Antenatal intervention was performed in 4 fetuses (thoraco-amniotic shunts [n = 3] and percutaneous intrauterine laser therapy [n = 1]). Sixty-four (96%) of the fetuses were born alive. There was 1 termination of pregnancy and 2 intrauterine deaths (all severe microcystic lesions). Forty-two infants (63%) underwent thoracotomy and appropriate excisional surgery at a median of 7.5 months (range, 1 day to 34 months). Two infants (which included the fetus having intrauterine laser therapy) died early in the postnatal period. Both were large microcystic lesions and had antenatal features of severe fetal distress. Twelve infants were investigated in the postnatal period but did not undergo surgery. Ten infants were not appropriately investigated or were lost to follow-up. Histologic examination showed definitive diagnostic features of CCAM (n = 25) or PS (n = 6). Other lesions with hybrid features of both were also seen (n = 11). There was a degree of correlation between antenatal ultrasound features (size of cyst [P = .03], in-utero behavior [P = .06], mediastinal shift [P = 0.05]) and the need for surgery but not with the final histologic diagnosis. Surgical excision was required in 45% of lesions showing late-gestation “resolution.”

Conclusions

Antenatally diagnosed “cystic lung disease” has an excellent prognosis in the absence of signs of severe fetal distress. The need for surgery should be based on appropriate postnatal investigations (eg, CT scans), rather than on antenatal behavior.     

Prenatal diagnosis and management of abdominal diseases in pediatric surgery

Purpose

The aim of this study was to investigate the prenatal courses and management of abdominal surgical diseases.

Methods

Of the 327 patients registered with our fetal treatment board since March 2002, 83 fetuses referred to the surgical department were enrolled for the current study. The prenatal diagnosis, sequential fetal images, and perinatal courses of these cases were reviewed retrospectively.

Results

Of the 83 cases, abdominal diseases were suspected in 34, lung and thoracic diseases in 25, genitourinary diseases in 12, and other anomalies in 12. Meconium peritonitis (MP), intestinal obstruction, and abdominal wall defects accounted for approximately 65% of the abdominal diseases. Five patients with prenatally diagnosed lung diseases underwent fetal surgical intervention, and 17 of the 22 liveborn patients survived. In contrast, none of the patients with prenatally diagnosed abdominal anomalies underwent fetal surgical intervention, yet, 23 of the 24 liveborn patients survived. However, preterm labor and hydrops were seen frequently in the patients with giant cystic MP, suggesting a fetal critical condition.

Conclusions

Although the clinical outcome of abdominal diseases seemed favorable with postnatal treatment, the current results suggested the occurrence of hidden mortality in utero and the potential need for fetal intervention for some abdominal conditions, such as MP.     

Congenital high airway obstruction syndrome: natural history and management

Background

Congenital high airway obstruction syndrome (CHAOS) is a life-threatening condition with a poorly understood natural history.

Methods

A retrospective review of five patients with CHAOS between 1997 and 2002 was performed.

Results

All fetuses had large echogenic lungs, dilated airways, inverted diaphragms, and massive ascites. One fetus with a laryngeal cyst was terminated at 22 weeks. A twin fetus with findings suggestive of a tracheal web had progressive hydrops, which led to fetal demise. The remaining 3 patients delivered via the ex utero intrapartum treatment (EXIT) procedure survived. The first patient tolerated progressive hydrops for 12 weeks in utero. He had tracheal atresia but underwent laryngotracheoplasty successfully. He is the first long-term CHAOS survivor and is speaking at 5 years of age. The 2 patients with relatively stable lung volumes prenatally have laryngeal atresia with a pinpoint posterior laryngeal fistula. Their postnatal clinical courses were much more benign than the first survivor.

Conclusions

The prenatal natural history and postnatal course of CHAOS depends on whether the airway obstruction is complete. The EXIT procedure offers the potential for salvage of this otherwise lethal condition. Hydrops may be well tolerated prenatally for weeks with potential resolution if airway fistulization is present.     

Early delivery as an alternative management strategy for selected high-risk fetal sacrococcygeal teratomas

Background

Large, prenatally diagnosed sacrococcygeal teratomas (SCTs) present a formidable challenge because of their unpredictable growth and propensity for complications. In our experience, even with aggressive serial imaging, many fetuses have died under a policy of “watchful waiting.” We propose “early delivery” as the best option for selected cases of high-risk fetal SCT.

Methods

The medical charts of all fetuses with SCT followed up at our institution and delivered before 32 weeks of gestation were reviewed for radiologic findings, fetal interventions, delivery information, perinatal inpatient course, and autopsy or discharge report.

Results

Between 1996 and 2009, excluding those that underwent fetal surgery, 9 patients with fetal SCT were delivered before 32 weeks of gestation. Four had type I tumors, and 5 had type II tumors. Of the 9 fetuses, 4 survived the neonatal period. The only surviving patient delivered before 28 weeks underwent an ex utero intrapartum therapy procedure.

Conclusions

A significant number of pregnancies complicated by high-risk SCT will manifest signs of fetal or maternal decompensation, or both, between 27 and 32 weeks of gestation. In the absence of fulminant hydrops, preemptive early delivery can be associated with surprisingly good outcomes in appropriately selected fetuses with high-risk SCT.     

Resolution of hydrops fetalis in congenital cystic adenomatoid malformation after prenatal steroid therapy

Background/Purpose: Development of hydrops fetalis in fetuses with congenital cystic adenomatoid malformations (CCAM) is a significant risk factor for fetal or neonatal demise. In rare cases, resolution of CCAM has occurred, presumably owing to lesion maturation or involution. Steroid therapy, utilized for lung maturity, has been postulated to accelerate this process. The natural history of hydropic fetuses with CCAM after receiving steroid therapy is presented. Methods: The authors prospectively followed up with 3 patients who had antenatally diagnosed CCAM and nonimmune hydrops fetalis with predicted mortality. All patients declined or were not candidates for fetal intervention and were treated with standard prenatal betamethasone to increase lung maturity. Results: Three fetuses had CCAM and nonimmune hydrops fetalis diagnosed prenatally. After a course of prenatal steroids during the second trimester, all 3 patients had resolution of their hydrops and were delivered at term without respiratory distress. Conclusions: Nonimmune hydrops fetalis in fetuses with congenital cystic adenomatoid malformation is a harbinger for fetal demise. The resolution of hydrops in these patients after receiving steroid therapy is an interesting and compelling observation. Because the mechanism of this process is speculative, further studies are needed to elucidate the relationship between antenatal steroids and maturation of congenital cystic adenomatoid malformation. J Pediatr Surg 38:508-510.     

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.     

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.     

Pulmonary vascular morphology in a fetal rabbit model for congenital diaphragmatic hernia

Background/Purpose

Although the pulmonary vascular abnormalities in congenital diaphragmatic hernia (CDH) are described from a morphologic point of view, the treatment of pulmonary hypertension (PH) remains one of the main unsolved problems in clinical daily practice. For this reason, detailed studies in well-validated animal models could still be of significance in our understanding of the pathogenesis of CDH.

Methods

In does of 23 days’ gestational age (GA), 39 fetuses underwent creation of diaphragmatic hernia (DH) and 15 fetuses a sham thoracotomy (SHAM). Thirty-nine nonoperated littermates served as internal controls (CTR). Fetuses were harvested by cesarean section on days 25, 27, 29, and 30 of gestation. Lung specimens were obtained and formalin fixed for further vascular morphometry studies.

Results

Lung vessels from DH fetuses started to show significantly smaller internal diameter (ID), external diameter (ED), larger arterial wall thickness (WT), and, in particular, a proportionally higher medial thickness (%MT) and adventitial thickness (%AT) from day 27 onward when compared with control fetuses. SHAM fetuses, which were harvested at term, showed no differences with CTR.

Conclusions

This is the first report documenting changes over time in the vascular system in a rabbit fetal model of surgically induced DH. These changes mimic pathologic findings observed in human fetuses and are also concordant with earlier observations in the surgical ovine model and the toxic nitrofen rat model.     

In utero repair of gastroschisis in the sheep (Ovis aries) model

Objective

Gastroschisis is associated with inflammatory changes in the exposed bowel which leads to intestinal dysmotility after postnatal repair. The insult is a combined effect of amniotic fluid exposure and mechanical constriction. We hypothesized that in utero anatomic repair is possible in a sheep model, and that it may halt the inflammatory damage caused by both mechanisms.

Methods

Gastroschisis was surgically created in mid-gestation (day 75) in 8 sheep fetuses. On gestational day 100, 2 fetuses underwent open fetal gastroschisis repair, where the eviscerated bowel was returned to the peritoneal cavity, and the abdominal wall was primarily closed. All fetuses were harvested at 135 days of gestation.

Results

Six fetuses survived the initial operation, and both fetuses that underwent gastroschisis repair survived to term. At 100 and 135 days of gestation, the eviscerated bowel showed progressive signs of inflammation and peel development. The gross and microscopic inflammatory changes in the gastroschisis bowel at 100 days of gestation were completely resolved at term following in utero repair.

Conclusion

In utero anatomic repair of gastroschisis is possible in mid-gestation in the fetal lamb model, and it appears to ameliorate the inflammatory process.