Mainstem bronchial atresia: a lethal anomaly amenable to fetal surgical treatment

Purpose

The purpose of this study was to review the unique imaging characteristics, prenatal course, and outcomes for fetuses with mainstem bronchial atresia (MBA).

Methods

The records of all patients referred for a fetal lung malformation from 2001 to 2012 and the medical literature were reviewed to identify cases of MBA.

Results

Of 129 fetuses evaluated, 3 were diagnosed prenatally with right-sided MBA. The first had a CCAM-volume ratio (CVR) of 9, hydrops, mirror syndrome, and preterm delivery of a nonviable fetus. The second (CVR 2.6) had ascites, preterm delivery at 34-weeks, and neonatal demise. The third fetus (CVR 5.7) presented with hydrops at 21-weeks, prompting fetal pneumonectomy. Postoperatively, hydrops resolved, and the contralateral lung grew dramatically, but preterm delivery occurred 3 weeks later. Ventilation could not be sustained, and the infant died. Four similar cases of MBA were in the literature, all right-sided. Two fetuses with hydrops delivered at 25-weeks and died immediately. One pregnancy was terminated. One fetus underwent pneumonectomy at 24-weeks but died intraoperatively.

Conclusion

MBA is a rare and lethal lesion that must be distinguished from other right-sided lung masses. Fetal pneumonectomy can be performed with resolution of hydrops and compensatory contralateral lung growth, but remains limited by complications of preterm birth.     

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.     

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.     

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.     

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.     

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.     

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.     

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.     

Cystic adenomatoid malformation volume ratio predicts outcome in prenatally diagnosed cystic adenomatoid malformation of the lung

Background/Purpose: Cystic adenomatoid malformation of the lung (CAM) diagnosed in utero has a variable natural history that may result in hydrops in up to 40% or regress in up to 15%. No criteria have been available to determine which lesions would grow and develop hydrops versus those whose growth would stabilize or regress. To better understand the natural history of CAM the authors developed a measure of tumor volume normalized for gestation age, the CAM volume ratio, or CVR. The results of an initial retrospective review of CVR at presentation suggested its usefulness as a predictor of outcome in CAM. The authors now report the results of prospective use of the CVR both to track tumor growth and regression during gestation and confirm its predictive value in fetuses with CAM. Methods: In the retrospective review performed between November 1998 and August 1999, 32 fetuses with CAM were reviewed and divided into those with hydrops and those in whom hydrops never developed. The CVR was determined by measuring 3 dimensions of the CAM using the formula for the volume of an ellipse and dividing by the head circumference to correct for differences in gestational age. Of the 32 fetuses in the retrospective study, the 8 that had hydrops had a significantly higher CVR (3.1 [plusmn] 1.1) compared with hydropic fetuses (0.74 [plusmn] 0.48; P [lt ] .001). The mean of the nonhydropic fetus's CVR plus 2 standard deviations (0.74 + 0.96 = 1.7) was used as a cutoff in the subsequent prospective study. From September 1, 1999 through March 1, 2001, the authors evaluated prospectively 58 patients with CAM by CVR measurement. These patients were followed up with serial ultrasound scans, and CVR at presentation correlated with the development of hydrops, survival, need for fetal intervention, and the need for ventilatory support or extracorporeal membrane oxygenation (ECMO), and length of hospital stay postnatally. The indication for fetal intervention was the development of hydops. Results: The fetuses with CVR [le ]1.6 (n = 42) were considered to be at low risk for the development of hydrops, and those with CVR greater than 1.6 (n = 16) were considered at increased risk for developing hydrops. Of the 42 fetuses in the low-risk group, 7 (16.7%) developed hydrops, and all but 1 had a dominant cyst. If CAMs with a dominant cyst are excluded, only 1 of 36 (2.8%) of CAMs with CVR [le ] 1.6 developed hydrops (P [lt ] .001). In fetuses with CVR at presentation more than 1.6, 12 of 16 (75%; P [lt ] .005) developed hydrops. Seventeen fetuses underwent fetal treatment (8 CVR [le ] 1.6; 9 CVR [gt ] 1.6): 7 patients required open fetal surgery (survival rate, 2 of 7), 6 patients thoracoamniotic shunting (survival rate, 6 of 6); and 4 patients cyst aspiration (survival rate, 4 of 4). All survivors of fetal intervention required at a least brief period of ventilatory support; none required ECMO. Conclusions: A CVR of greater than 1.6 at presentation accurately predicts increased risk of hydrops developing in CAM. A CVR of [le ]1.6 at presentation suggests that the risk of hydrops developing in the absence of a dominant cyst is less than 3%. The CVR is a useful sonographic indicator of fetuses at risk for hydrops who require close ultrasound observation and possible fetal intervention.     

Residual congenital cystic adenomatoid malformation and thoracic scar deformation after fetal surgery: a case report

Fetal surgery is a treatment option for fetuses with congenital cystic adenomatoid malformation (CCAM) of the lung who develop hydrops before 32 weeks of gestation. We report on a fetus with CCAM and hydrops who underwent subtotal resection of a huge right, lower lobe CCAM at 20 weeks of gestation. Postnatally, the infant developed a thoracic scar deformation and was suspected to have residual CCAM. The residual CCAM was resected and the chest wall deformity was corrected at 3 1/2 years of age.     

Bronchial atresia: the hidden pathology within a spectrum of prenatally diagnosed lung masses

Purpose

This study was aimed at determining whether different congenital lung masses represent diverse manifestations of a single developmental abnormality associated with fetal airway obstruction.

Methods

We conducted a 3-year retrospective review of patients who underwent surgical resection of a prenatally diagnosed lung mass. Prenatal imaging was used to define mass position and its effect on adjacent organs. Lung specimens were examined through careful full-specimen microdissections, as well as by plain and contrast roentgenograms.

Results

Twenty-five patients underwent lung resection during this study period. Based on the final pathology reports, 56% were congenital cystic adenomatoid malformations, 12% were congenital lobar emphysemas, 8% were bronchopulmonary sequestrations, and 24% had features of both cystic adenomatoid malformation and bronchopulmonary sequestrations. No bronchogenic cysts were present in this series. Overall, bronchial atresia was identified in 77% of the examined specimens (n = 22) and was associated with all types of lung malformations.

Conclusions

Bronchial atresia is a common, unrecognized component of prenatally diagnosed congenital cystic adenomatoid malformations, bronchopulmonary sequestrations, congenital lobar emphysemas, and lesions of mixed pathology. Most congenital lung masses may be part of a spectrum of anomalies linked to obstruction of the developing fetal airway as an underlying component in their pathogenesis.     

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.     

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.     

Fetal cystic adenomatoid malformation: prenatal diagnosis and natural history

We studied the natural history and pathophysiology of congenital cystic adenomatoid malformation (CCAM) detected prenatally by ultrasound in twelve fetuses. Two types of fetal CCAM can be distinguished by gross anatomy, ultrasound findings, and prognosis. Microcystic lesions are usually associated with fetal hydrops and have a poor prognosis (five cases with one survivor). Antenatal diagnosis, maternal transport, and immediate thoracotomy after birth allowed the first reported survival of a newborn with a large microcystic CCAM. Macrocystic lesions are not usually associated with hydrops and have a favorable prognosis (five of seven survived). We conclude that fetuses with hydrops are at high risk for fetal or neonatal demise without intervention. Fetuses with CCAM but without hydrops have a good chance for survival with maternal transport, planned delivery, and immediate neonatal resuscitation and surgery.     

Ex utero intrapartum treatment with placement on extracorporeal membrane oxygenation for fetal thoracic masses

Purpose

We describe our experience with fetuses diagnosed with life-threatening chest masses who were delivered by ex utero intrapartum treatment with placement on extracorporeal membrane oxygenation (EXIT-to-ECMO).

Methods

The first fetus presented with a cystic mediastinal mass and enlarging echogenic lungs. Bronchoscopic evaluation during ex utero intrapartum treatment (EXIT) revealed complete airway obstruction secondary to a carinal bronchogenic cyst. The second fetus presented with a massive left congenital cystic adenomatoid malformation. The EXIT procedure was performed because of significant mediastinal shift, severe compression of the normal lung parenchyma, and signs of fetal distress.

Results

In both cases, extracorporeal membrane oxygenation (ECMO) was initiated while on placental support. The fetuses were then delivered, and a definitive resection of their thoracic lesions was successfully performed. There were no major perioperative complications. Both children made expedient recoveries without significant cardiopulmonary sequelae.

Conclusion

To our knowledge, this is the first report describing the successful use of EXIT-to-ECMO as a bridge to definitive resection of large chest masses diagnosed in utero. EXIT-to-ECMO is a novel and effective management strategy for stabilizing patients with profound respiratory compromise secondary to congenital thoracic lesions.     

Survival after CCAM associated with ascites: a report of a case and review of the literature

A congenital cystic adenomatoid malformation (CCAM) is a congenital lung lesion that, when associated with hydrops, is thought to have a dismal prognosis without fetal intervention. The authors report a case of a fetus with a CCAM associated with ascites as the only manifestation of hydrops, which was diagnosed at 19 weeks gestation. The CCAM regressed without intervention between 23 and 29 weeks of gestation with resolution of the ascites. The baby was born asymptomatic at term, and the infant underwent elective resection of the CCAM at 1 year of age. A review of the literature from 1980 to 2000 yielded 9 other cases of spontaneous resolution of hydrops associated with CCAM, suggesting that although rare, this outcome is a possibility in fetuses diagnosed with the condition. Because most fetuses diagnosed with hydrops undergo termination of pregnancy, the true incidence of hydrops resolution is potentially higher than predicted. This has important implications for prenatal counseling particularly in centers in which fetal intervention is not available.     

Quantitative analysis of sacral parasympathetic nucleus innervating the rectum in rats with anorectal malformation

Background/Purpose

The purpose of this experiment was to identify the neurons in the lumbosacral spinal cord involved in colon-rectal function and to compare normal and anorectal malformation of fetalrats.

Methods

The authors quantified the sacral parasympathetic nucleus (SPN) innervation of the rectum by Fluorogold (FG) (Fluorochrome, Englewood, CO) retrograde tracing experiment in fetal rats with normal and anorectal malformation. Anorectal malformation was induced in rat fetuses by ethylenethiourea (ETU). The number of FG-labeled SPNs was scored and compared between male fetuses with or without malformation in the ETU-fed group and control groups.

Results

The number of FG-labeled SPNs in the fetuses without a defect, with ETU injected but without any defects of the anorectum or neural tube, with low-type deformity, and with high-type deformity were (mean ± SEM) 47.3 ± 2.9, 45.6 ± 3.2, 24.2 ± 3.8, and 8.5 ± 2.5, respectively. Fluorogold-labeled SPNs inthe fetuses with high-type deformity were significantly fewer than those in fetuses without defects (P<.05) and in controls (P < .05).

Conclusions

These findings suggest that defective SPN innervation to the rectum is a primary anomaly that coexists with the alimentary tract anomaly in anorectal malformation during fetal development. The intrinsic neural deficiency is an important factor likely to contribute to poor postoperative anorectal function despite surgical correction of the malformation.     

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.