Using MRI-derived observed-to-expected total fetal lung volume to predict lethality in fetal skeletal dysplasia.

BACKGROUND: Pulmonary hypoplasia is the primary cause of perinatal death in lethal skeletal dysplasias. The antenatal ultrasound correlates for lethality are indirect, measuring the thorax (thoracic circumference, TC) or femur compared to the abdomen (TC/AC, FL/AC). A single study has correlated lethality with the observed-to-expected total lung volume (O/E-TFLV) on fetal MRI in 23 patients. OBJECTIVE: Our aim was to define a cutoff value to predict lethality more specifically using MRI-derived O/E-TFLV. MATERIALS AND METHODS: Two large fetal center databases were searched for fetuses with skeletal dysplasia and MRI; O/E-TFLV was calculated. Ultrasound measures were included when available. Each was evaluated as a continuous variable against lethality (stillbirth or death in the first month of life). Logistic regression and receiver operating characteristic (ROC) curve analyses evaluated the prediction ability. AUC, sensitivity, and specificity were calculated. P < 0.05 was considered statistically significant. RESULTS: A total of 80 fetuses met inclusion criteria. O/E-TFLV < 0.49 was a significant risk factor in predicting lethality, with sensitivity and specificity of 0.63 and 0.93, respectively, and an AUC of 0.81 (P < 0.001). FL/AC < 0.129 was also a strong variable with sensitivity, specificity, and AUC of 0.73, 0.88, and 0.78, respectively (P < 0.001). TC/AC and TC percentile were not significant risk factors for lethality. An O/E-TFLV of < 0.38 defines a specificity for lethality at 1.00. CONCLUSION: MRI-derived O/E-TFLV and US-derived FL/AC are significant predictors of lethality in fetuses with skeletal dysplasia. When prognosis is uncertain after ultrasound, calculation of MRI-derived O/E-TFLV may provide additional useful information for prognosis and delivery planning.

Prenatal lung volumes in congenital diaphragmatic hernia and their effect on postnatal outcomes.

Lung volume measurement on fetal MRI is a component of the imaging workup for various prenatal conditions, but its use as a prognosticator has been most heavily studied in congenital diaphragmatic hernia (CDH). Pediatric radiologists who perform and interpret fetal MRI must be familiar with the technical aspects of lung volume measurement to guarantee accurate measurement and reporting. Variability in timing and type of measurement at different fetal centers also requires pediatric radiologists to be up-to-date with the literature and aware of their center's internal data. This paper provides both a how-to guide for measuring fetal lung volumes on MRI and a comprehensive review of the CDH outcome literature to serve as a convenient reference for the pediatric radiologist.

Characterization of the Hyperintense Bronchus Sign as a Fetal MRI Marker of Airway Obstruction.

Background Fetal MRI-based differential diagnosis of congenital lung malformations is difficult because of the paucity of well-described imaging markers. Purpose To characterize the hyperintense bronchus sign (HBS) in in vivo fetal MRI of congenital lung malformation cases. Materials and Methods In this retrospective two-center study, fetal MRI scans obtained in fetuses with congenital lung malformations at US (January 2002 to September 2018) were reviewed for the HBS, a tubular or branching hyperintense structure within a lung lesion on T2-weighted images. The frequency of the HBS and respective gestational ages in weeks and days were analyzed. Areas under the curve (AUCs), 95% CIs, and P values of the HBS regarding airway obstruction, as found in histopathologic and postnatal CT findings as the reference standards, were calculated for different gestational ages. Results A total of 177 fetuses with congenital lung malformations (95 male fetuses) and 248 fetal MRI scans obtained at a median gestational age of 25.6 weeks (interquartile range, 8.9 weeks) were included. The HBS was found in 79% (53 of 67) of fetuses with bronchial atresia, 71% (39 of 55) with bronchopulmonary sequestration (BPS), 43% (three of seven) with hybrid lesion, 15% (six of 40) with congenital cystic adenomatoid malformation, and 13% (one of eight) with bronchogenic cyst at a median gestational age of 24.9 weeks (interquartile range, 9.7 weeks). HBS on MRI scans at any gestational age had an AUC of 0.76 (95% CI: 0.70, 0.83; P = .04) for the presence of isolated or BPS-associated airway obstruction at histopathologic analysis and postnatal CT. The AUC of HBS on fetal MRI scans obtained until gestational age of 26 weeks (AUC, 0.83; 95% CI: 0.75, 0.91; P < .001) was significantly higher (P = .045) than that for fetal MRI scans obtained after gestational age 26 weeks (AUC, 0.69; 95% CI: 0.57, 0.80; P = .004). Conclusion The hyperintense bronchus sign is a frequently detectable feature at fetal MRI and is associated with airway obstruction particularly before gestational age 26 weeks. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Dubinsky in this issue.

Impact of the cystic neural tube defects on fetal motor function in prenatal myelomeningocele repairs: A retrospective cohort study.

OBJECTIVE: To determine the impact of the lesion type (cystic [myelomeningocele] or flat [myeloschisis]) on the fetal motor function (MF) in cases candidates for prenatal open neural tube defect (ONTD) repair. METHODS: Retrospective cohort study of patients with ONTD who underwent prenatal repair at a single institution between 2011 and 2019. The lesion type and the measurements of the length and width of the lesions to calculate the surface of the ellipsoid lesion were performed using MR scans. Prenatal MF of the lower extremities was evaluated by ultrasound following a metameric distribution at the time of referral. Intact MF was defined as the observation of plantar flexion of the ankle. Logistic regression was performed to determine the predictive value of the type of lesion for having an intact MF at the time of referral. RESULTS: 103 patients were included at 22.9 (19-25.4) weeks; 65% had cystic and 35% had flat lesions. At the time of referral, there was a higher proportion of cases with an intact MF in the presence of flat lesions (34/36; 94.4%) as compared to cystic lesion (48/67; 71.6%, p < 0.01). When adjusting for gestational age and anatomical level of the lesion, flat ONTD were 3.1 times more likely to be associated by intact motor function (CI%95 [2.1-4.6], p < 0.01) at the time of referral. CONCLUSION: Cystic ONTD are more likely to be associated with impaired MF at mid-gestation in candidates for prenatal ONTD repair.

Prenatal Imaging to Predict Need for Urgent Perinatal Surgery in Congenital Lung Lesions.

BACKGROUND: Congenital lung malformations (CLMs) have a variable natural history: some patients require urgent perinatal surgical intervention (UPSI) and others remain asymptomatic. These lesions have potential growth until 26-28 wk gestation. CLM volume ratio (CVR) has been shown to predict the risk of hydrops in CLMs. However, no criteria exist to delineate lesions requiring urgent surgical intervention in the perinatal period. Our goal was to determine prenatal diagnostic features that predict the need for UPSI in patients diagnosed with CLM. METHODS: Records and imaging features of all fetuses evaluated by our fetal center between May 2015 and December 2018 were retrospectively reviewed. Data included demographics, fetal ultrasound and magnetic resonance imaging, CVR, surgical treatment, and outcome. Features were analyzed for their ability to predict the need for UPSI. RESULTS: Sixty-four patients were referred for CLM, with 48 patients serially followed. Nine (18.8%) patients were followed nonoperatively, 35 (72.9%) underwent resection, and four (8.3%) were lost to follow-up. Of the patients who underwent resection, 24 (68.5%) were electively resected and 11 were urgently resected. Five (14.3%) patients underwent ex utero intrapartum treatment resection, and six (17.1%) were urgently resected for symptomatic CLM. There were no cases of UPSI with final CVR <1.1. Of the patients with final CVR 1.1-1.7, 43% required urgent resection. CVR ≥1.1 has 100% sensitivity and 87.8% specificity to predict patients requiring UPSI (area under the curve of 0.98). CONCLUSIONS: A final CVR ≥1.1 is highly predictive for UPSI. Patients with a final CVR ≥1.1 should be referred for delivery at centers with pediatric surgeons equipped for potential UPSI for CLM.

Congenital diaphragmatic hernia.

Congenital diaphragmatic hernia (CDH) is a potentially severe anomaly that should be referred to a fetal care center with expertise in multidisciplinary evaluation and management. The pediatric radiologist plays an important role in the evaluation of CDH, both in terms of anatomical description of the anomaly and in providing detailed prognostic information for use in caring for the fetus and pregnant mother as well as planning for delivery and postnatal care. This article reviews the types of hernias, including distinguishing features and imaging clues. The most common methods of predicting severity are covered, and current fetal and postnatal therapies are explained. The author of this paper provides a handy reference for pediatric radiologists presented with a case of CDH as part of their daily practice.

Timing of Prenatal Magnetic Resonance Imaging in the Assessment of Congenital Diaphragmatic Hernia.

INTRODUCTION: Fetal magnetic resonance imaging (MRI) has been used to stratify severity of congenital diaphragmatic hernia (CDH) after ultrasound diagnosis. The purpose of this study was to determine if timing of MRI influenced prediction of severity of outcome in CDH. METHODS: A single institution retrospective review of all CDH referred to our institution from February 2004 to May 2017 was performed. Patients were included if they underwent at least 2 fetal MRIs prior to delivery. Prenatal MRI indices including observed-to-expected total fetal lung volume (o/e TFLV) were evaluated. Indices were categorized by trimester, either 2nd (20-27 weeks gestation) or 3rd trimester (>28 weeks gestation) and further analyzed for outcome predictability. Primary outcomes were survival, extracorporeal membrane oxygenation (ECMO), and pulmonary hypertension (PAH). Student t test and logistic and linear regression were used for data analyses. RESULTS: Of 256 fetuses evaluated for CDH, 197 were further characterized by MRI with 57 having both an MRI in the 2nd and 3rd trimesters. There was an average of 9.95 weeks (±4.3) between the 1st and 2nd MRI. Second trimester o/e TFLV was the only independent predictor of survival by logistic regression (OR 0.890, p < 0.01). Third trimester MRI derived lung volumes were associated with, and independent predictors of, severity of PAH and need for ECMO. Interval TFLV growth was a strong predictor of PAH postnatally (OR 0.361, p < 0.01). Overall cohort survival was 79%. CONCLUSION: Accuracy of MRI lung volumes to predict outcomes is dependent on the -gestational age at the time of exam. While MRI lung volumes at either the 2nd or 3rd trimester are predictive of morbidity, 2nd trimester lung volumes strongly correlated with mortality.

Prenatal Imaging Features and Postnatal Factors Associated with Gastrointestinal Morbidity in Congenital Diaphragmatic Hernia.

BACKGROUND: To perform a comprehensive assessment of postnatal gastrointestinal (GI) morbidity and determine the prenatal imaging features and postnatal factors associated with its development in patients with congenital diaphragmatic hernia (CDH). MATERIALS AND METHODS: A retrospective review was conducted of all infants evaluated for CDH at a quaternary fetal center from February 2004 to May 2017. Prenatal imaging features and postnatal variables were analyzed. GI morbidity was the primary outcome. The Mann-Whitney U test, the Kruskal-Wallis test with Dunnett's T3 post hoc analysis and logistic regression, and the χ2 test were performed when appropriate. RESULTS: We evaluated 256 infants; 191 (75%) underwent CDH repair and had at least 6 months of follow-up. Of this cohort, 60% had gastroesophageal reflux disease (GERD), 13% had gastroparesis, 32% received a gastrostomy tube (G-tube), and 17% needed a fundoplication. Large defect, patch repair, extracorporeal membrane oxygenation (ECMO), and prolonged use of mechanical ventilation were significantly associated with having GERD, gastroparesis, G-tube placement, and fundoplication (p < 0.05). Fetuses with stomach grades 3 and 4 were most likely to have GERD, a G-tube, and a long-term need for supplemental nutrition than fetuses with stomach grades 1 and 2 (p < 0.05). CONCLUSION: Survivors of CDH with large defects, prolonged use of mechanical ventilation, or that have received ECMO may be at an increased risk for having GERD, gastroparesis, and major GI surgery. Marked stomach displacement on prenatal imaging is significantly associated with GI morbidity in left-sided CDH.

Physiologic Ovarian Cysts versus Other Ovarian and Adnexal Pathologic Changes in the Preadolescent and Adolescent Population: US and Surgical Follow-up.

Background Ovarian and adnexal cysts are frequently encountered at US examinations performed in preadolescent and adolescent patients, yet there are few published studies regarding the outcomes of cysts in this population. Purpose To identify characteristics at US that help to distinguish physiologic ovarian cysts from nonphysiologic entities. Materials and Methods Female patients who underwent pelvic US with or without Doppler from January 2009 through December 2013 were identified by using a centralized imaging database. Patients older than 7 years and younger than 18 years with ovarian or adnexal cysts at least 2.5 cm were included. Demographic characteristics, date of surgery, surgical notes, and pathologic reports were extracted from the electronic medical record. Initial and follow-up dates of US, cyst size and complexity, imaging diagnosis, and change on subsequent US images were recorded. Statistical analysis was performed with the Wilcoxon rank sum and Kruskal-Wallis tests for continuous variables and the Fisher exact test for categorical variables. Results Of 754 patients who met inclusion criteria (age, 8-18 years; mean age, 14.6 years ± 1.9 [standard deviation]; mean cyst size, 5 cm ± 3.3), 409 patients underwent complete follow-up that included resolution at imaging (n = 250) or surgery (n = 159). In the patients with complete imaging follow-up, mean time to US documentation of resolution was 194 days ± 321; 59.6% (149 of 250) patients had nonsimple cyst characteristics. One-hundred fifty-nine patients underwent surgical intervention (mean cyst size, 8.5 cm ± 5.3), and 69.8% (111 of 159) of the cysts had simple characteristics. Of the 159 cysts, 100 (62.8%) were defined in the pathologic report as paratubal cysts. Of 409 patients, no malignancies were encountered in this study population with surgical or imaging resolution. Conclusion No malignancies were encountered in the study population and the majority of cysts resolved at follow-up imaging. Large size, persistence, and separability from the ovary were most helpful for identification of nonphysiologic paratubal cysts. © RSNA, 2019.

Cervical lymphatic malformations: Prenatal characteristics and ex utero intrapartum treatment.

BACKGROUND: The ex utero intrapartum treatment (EXIT) is utilized to transition fetuses with prenatally diagnosed airway obstruction to postnatal life. We describe the unique clinical course, diagnosis, treatment, and outcomes of patients with cervical lymphatic malformation (CLM) managed with EXIT. METHODS: Review of fetuses with diagnosed CLM was delivered by EXIT (2001-2018) in a tertiary referral fetal center. Outcomes included survival, tracheostomy at discharge, neonatal course after delivery, and pulmonary hypoplasia. Data are reported as median [range] and rate (%). RESULTS: Out of 45 patients delivered by EXIT, 10 were delivered for CLM: seven had polyhydramnios, one had nonimmune hydrops, five delivered preterm, and three were emergency EXITs. The EXIT time and estimated blood loss were 125 minutes (95, 158) and 900 mL (500, 1500), respectively. Airway was secured in all. There was one neonatal death (day 8) with prematurity, sepsis, and pulmonary hypoplasia. Three out of nine were discharged with a tracheostomy. CONCLUSION: In CLM, close monitoring for structural neck involvement and development of polyhydramnios are important and may be an indication for EXIT as the optimal delivery mode. An experienced multidisciplinary team is a key factor for an effective approach to the obstructed airway in CLM.

Correlation between maternal meal and fetal motion during fetal MRI.

BACKGROUND: Motion remains a major limitation of fetal magnetic resonance imaging (MRI). Some centers have required mothers to fast before MRI in an effort to reduce motion; however, there is no current literature that describes the effect of maternal diet on fetal activity. OBJECTIVE: The objective is to define associations between specific foods and beverages consumed before and the severity of fetal motion during fetal MRI. MATERIALS AND METHODS: Patients were asked to recall the specific foods or drinks consumed before their scan. An experienced technologist rated the level of fetal activity on a 3-point scale, from much less motion than normal (1) to much more (3). Two hundred twenty-eight patients were included. A non-inferiority test was used to establish statistical equivalence between the MR scores of those having a particular food item and those not. For items not shown to be equivalent, an additional superiority analysis evaluated for the presence of any significant difference. Additional data on time from meal to MRI and amniotic fluid index were also analyzed. RESULTS: Eleven of 15 comparisons were statistically significant for equivalence (P<0.05). In the remaining four categories, a superiority analysis revealed no significant differences. Analysis of meal-to-scan times showed no significant association with mean MR score (P=0.57). Amniotic fluid index correlated positively with scores, but the association was not statistically significant (P=0.39). CONCLUSION: Neither fasting nor a specific consumption was associated with a significant difference in fetal motion on MR. It is therefore likely unnecessary for mothers to alter their diets on the day of an MRI study.

Fetal Lung Volumes by MRI: Normal Weekly Values From 18 Through 38 Weeks' Gestation.

OBJECTIVE: The purpose of this study is to establish normal total fetal lung volume reference ranges from 18 to 38 weeks' gestation at 1-week intervals. MATERIALS AND METHODS: A retrospective analysis of 665 patients who underwent fetal MRI at two tertiary fetal centers from 2001 to 2013 was performed. Total fetal lung volume was measured in at least two planes, either manually or using a 3D workstation. The mean, median, SD, minimum, maximum, and lower and upper quartiles for total fetal lung volume were determined per gestational week. A t test was used to compare our values to previously reported values. A new formula to calculate total fetal lung volume derived from our data was created using a regression model. Comparisons between total fetal lung volume obtained by different imaging planes and manual versus semiautomatic calculation were also performed. RESULTS: The mean normal total fetal lung volume showed a weekly increase from 18 through 35 weeks' gestation. Means were compared with the expected total fetal lung volume generated by the Rypens formula, showing statistically significant lower mean total fetal lung volume from week 19 to week 22 (p < 0.05). Comparison between our data-derived total fetal lung volume formula and the Rypens formula showed very similar values at every gestational age. No difference in total fetal lung volume was seen when comparing imaging planes or manual versus semiautomatic methods. CONCLUSION: Measured mean total fetal lung volume values at 19-22 weeks are significantly lower than those predicted by the Rypens formula. Therefore, we propose preferential use of our values for prenatal counseling and delivery planning.

The impact of fetal endoscopic tracheal occlusion in isolated left-sided congenital diaphragmatic hernia on left-sided cardiac dimensions.

OBJECTIVES: Fetal endoscopic tracheal occlusion (FETO) is offered to fetuses with congenital diaphragmatic hernia (CDH) and severe lung hypoplasia to promote lung growth and may secondarily affect left heart growth. The effects of FETO on left heart hypoplasia (LHH) are not described post-CDH repair. METHODS: A retrospective analysis was performed for fetuses with left-sided CDH who underwent FETO and severity-matched controls from 2007 to 2016 at our institution. Echocardiographic, ultrasound, and MRI data were reviewed. Left heart dimensions were assessed prenatally and postnatally. Primary clinical outcome evaluated was death. RESULTS: Twelve FETO patients and 18 controls were identified. Fetal LHH was noted in both groups and worsened after FETO. Postnatal mitral valve dimensions were larger in the FETO group pre-CDH repair (P = .03). Post-CDH repair, mitral valve and left ventricular dimensions were not significantly different between groups (P = .79 and P = .63 respectively) while FETO aortic valve dimensions were smaller (P = .04). Extracorporeal membrane oxygenation use was lower in the FETO group. No associations were found between left heart dimensions and outcomes. CONCLUSION: Although increased lung growth was seen after FETO, fetal LHH persisted with relative normalization seen post-repair. Persistent LHH post-FETO could be secondary to a small contribution of pulmonary venous return to the fetal left heart and increased intrathoracic pressures post-FETO.

Fetal left-sided cardiac structural dimensions in left-sided congenital diaphragmatic hernia - association with severity and impact on postnatal outcomes.

OBJECTIVES: Fetuses with congenital diaphragmatic hernia (CDH) demonstrate varying degrees of left heart hypoplasia. Our study assesses the relationship between fetal left-sided cardiac structural dimensions, lung size, percentage liver herniation, lung-to-head ratio, postnatal left-sided cardiac structural dimensions, and postnatal outcomes. METHODS: We performed a retrospective cohort study of fetuses with left-sided CDH who had prenatal echocardiographic, ultrasound, and magnetic resonance imaging examinations at our institution between January 2007 and March 2015. Postnatal outcomes assessed include use of inhaled nitric oxide (iNO), use of extracorporeal membrane oxygenation, and death. RESULTS: Fifty-two fetuses with isolated left-sided CDH were included. Multivariate logistic regression models indicated that smaller fetal aortic valve z-score was associated with postnatal use of iNO (p = 0.03). Fetal mitral valve z-score correlated with lung-to-head ratio (p = 0.04), postnatal mitral valve z-score correlated with percent liver herniation (p = 0.03), and postnatal left ventricular end-diastolic dimension z-score correlated with liver herniation <20% (p = 0.04). CONCLUSION: We identified associations between smaller fetal left-sided cardiac structural dimensions and classic CDH indices. Smaller aortic valve z-score was associated with iNO use; however, left heart dimensions showed no association with extracorporeal membrane oxygenation or mortality. Further study into the impact of left-sided hypoplasia on outcomes in CDH is worthy of evaluation in a larger, prospective study. © 2017 John Wiley & Sons, Ltd.

Performance of computed tomography of the head to evaluate for skull fractures in infants with suspected non-accidental trauma.

BACKGROUND: Young children with suspected abusive head trauma often receive skull radiographs to evaluate for fractures as well as computed tomography (CT) of the head to assess for intracranial injury. Using a CT as the primary modality to evaluate both fracture and intracranial injury could reduce exposure to radiation without sacrificing performance. OBJECTIVE: To evaluate the sensitivity of CT head with (3-D) reconstruction compared to skull radiographs to identify skull fractures in children with suspected abusive head trauma. MATERIALS AND METHODS: This was a retrospective (2013-2014) cross-sectional study of infants evaluated for abusive head trauma via both skull radiographs and CT with 3-D reconstruction. The reference standard was skull radiography. All studies were read by pediatric radiologists and neuroradiologists, with ten percent read by a second radiologist to evaluate for interobserver reliability. RESULTS: One hundred seventy-seven children (47% female; mean/median age: 5 months) were included. Sixty-two (35%) had skull fractures by radiography. CT with 3-D reconstruction was 97% sensitive (95% confidence interval [CI]: 89-100%) and 94% specific (CI: 87-97%) for skull fracture. There was no significant difference between plain radiographs and 3-D CT scan results (P-value = 0.18). Kappa was 1 (P-value <0.001) between radiologist readings of CTs and 0.77 (P = 0.001) for skull radiographs. CONCLUSION: CT with 3-D reconstruction is equivalent to skull radiographs in identifying skull fractures. When a head CT is indicated, skull radiographs add little diagnostic value.

5, 4, 3, 2, 1: embryologic variants of pentalogy of Cantrell.

BACKGROUND: The purpose of this study was to evaluate our experience with pentalogy of Cantrell and the various embryologic variants. MATERIALS AND METHODS: Patient charts and diagnostic imaging studies of all fetuses evaluated at Texas Children's Fetal Center for pentalogy of Cantrell between April 2004 and June 2014 were reviewed retrospectively. Data collected from patient charts included demographic information, clinical presentation, fetal and postnatal imaging findings, operative treatment, pathologic evaluation, and outcomes. RESULTS: There were 10 patients who presented with embryologic variants of pentalogy of Cantrell over a 6-y period. Two cases displayed the full range of embryologic defects observed, and eight cases exhibited variants of the classic pentalogy. Sternal and pericardial defects were each present in 40% of patients. Additional anomalies present included pulmonary hypoplasia, pulmonary artery stenosis, and chromosomal abnormalities. Four patients presented with diaphragmatic defects but no defect in the pericardium, and one patient presented with a defective pericardium but no associated diaphragmatic defect, suggesting highly specific losses of somatic mesoderm during embryologic development. One patient was lost to follow-up, and a second patient underwent termination of pregnancy. Five of the remaining eight patients survived, one of which had the full range of embryologic defects and now attends preschool but requires speech and occupational therapy. The remaining surviving patients have developed without serious sequelae. CONCLUSIONS: This report highlights the spectrum of anomalies observed in the pentalogy of Cantrell and demonstrates that these fetuses can survive but with substantial morbidity.

Revisiting outcomes of right congenital diaphragmatic hernia.

BACKGROUND: Studies comparing outcomes of right- and left-sided congenital diaphragmatic hernia (R-CDH and L-CDH) have yielded conflicting results. We hypothesized that R-CDH is associated with higher short-term pulmonary morbidity than L-CDH. METHODS: We reviewed all CDH patients at a tertiary children's hospital over 10 y. In prenatally diagnosed CDH, the observed-to-expected total fetal lung volume and percentage liver herniation (%LH) were calculated using fetal magnetic resonance imaging-based measurements. Outcomes were compared in patients with isolated CDH. Patients were subsequently matched by %LH to compare outcomes. RESULTS: Of 189 CDH patients, 37 (20.1 %) were R-CDH and 147 (79.9%) were L-CDH. Those with R-CDH were prenatally diagnosed at a significantly lower rate (40.5% versus 73.5%; P < 0.001) and later gestational age (26.5 ± 7.7 versus 22.6 ± 5.65 wk; P = 0.062). There was no difference in observed-to-expected total fetal lung volume between those with R-CDH and L-CDH (30.2 ± 11.1% versus 33.1 ± 14.2%; P = 0.471). Fetuses with R-CDH had a higher %LH than those with L-CDH (37.5 ± 14.1% versus 18.6 ± 12.2%; P < 0.001). Patients with isolated R-CDH had a higher need for extracorporeal membrane oxygenation than L-CDH (48% versus 27%; P = 0.055). There was no difference in duration of tracheal intubation, hospital stay, need for supplemental oxygen at 30-d of life or 6-mo mortality between groups. There was no difference in mortality and pulmonary morbidity when patients were matched by %LH. CONCLUSIONS: Compared to those with L-CDH, fetuses with R-CDH are less likely to be diagnosed prenatally and have a higher need for extracorporeal membrane oxygenation. The sidedness of the hernia defect was not associated with differences in short-term pulmonary morbidity in this large, contemporary single-institution experience of neonates with CDH.

Predictive Value of MRI Findings for the Identification of a Hernia Sac in Fetuses With Congenital Diaphragmatic Hernia.

OBJECTIVE: The purpose of this study was to identify MRI features of diaphragmatic hernia sac, as well as to assess the accuracy of diagnosing a sac prenatally. MATERIALS AND METHODS: All fetal MRI examinations performed for intrapleural congenital diaphragmatic hernia (CDH) from 2004 to 2013 were retrospectively reviewed by two pediatric radiologists blinded to the hernia sac status (defined intraoperatively or at autopsy). Reviewers noted whether a sac was present on the basis of identification of the following four MRI findings: 1, meniscus of lung posterior or apical to the hernia contents; 2, encapsulated appearance of hernia contents, exerting less than expected mass effect on the heart and mediastinum; 3, presence of pleural fluid outlining a sac from above; and 4, presence of ascites outlining a sac from below. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each finding and for various combinations. Contingency tables, chi-square testing, and logistic regression were applied to calculate the probability of a sac. RESULTS: Ninety patients were included: 21 with and 69 without a sac. The first three MRI findings correlated with the presence of a sac. Logistic regression yielded high predicted probability of a sac when one finding was identified (finding 1, 94.4%; finding 2, 96.2%). Adding a second and a third finding improved the probability to 99.7% and 99.9%, respectively. Sensitivity and specificity for the presence of a sac were 0.43 and 0.97, respectively. PPV and NPV were 83.8% and 80%, respectively. CONCLUSION: On fetal MRI, presence of a hernia sac in CDH can be diagnosed with high specificity when indicative findings are present.

Improving spectral quality in fetal brain magnetic resonance spectroscopy using constructive averaging.

PURPOSE: A common source of loss in signal-to-noise ratio (SNR) in fetal brain magnetic resonance spectroscopy (MRS) is from fetal movement and temporal magnetic field drift. We investigated the feasibility of using constructive averaging strategies for improving the spectral quality and recovering the SNR loss from these effects. MATERIALS AND METHODS: Eight fetuses, between 20 3/7 and 38 2/7 weeks' gestation, were scanned with MRS at 1.5 T. Single-voxel point-resolved spectroscopy of the fetal brain with TE = 144 ms (in one case additional TE = 288 ms) was performed in a dynamic mode, and individual spectra of 128 acquisitions were saved. With constructive averaging strategy individual acquisitions were corrected for phase variations and frequency drift before averaging. Constructively averaged spectra were compared to those using conventional averaging to evaluate differences in spectral quality and SNR. RESULTS: The definition of key metabolite peaks was qualitatively improved using constructive averaging, including the doublet structure of lactate in one case. Constructive averaging was associated with SNR increases, ranging from 11% to 40%, and the SNR further improved in one case when outliers from severe motion were rejected before averaging. CONCLUSION: Our results demonstrate the feasibility of using constructive averaging for improving SNR in fetal MRS, which is likely to improve the characterization of fetal brain metabolites.