Decreased neonatal morbidity in 'stomach-down' left congenital diaphragmatic hernia: implications of prenatal ultrasound diagnosis for counseling and postnatal management

OBJECTIVE

To evaluate the influence of stomach position on postnatal outcome in cases of left congenital diaphragmatic hernia (CDH) without liver herniation, diagnosed and characterized on prenatal ultrasound (US), by comparing those with ('stomach-up' CDH) to those without ('stomach-down' CDH) intrathoracic stomach herniation.

METHODS

Infants with left CDH who underwent prenatal US and postnatal repair at our institution between January 2008 and March 2017 were eligible for inclusion in this retrospective study. Detailed prenatal US examinations, fetal magnetic resonance imaging (MRI) studies, operative reports and medical records of infants enrolled in the pulmonary hypoplasia program at our institution were reviewed. Cases with liver herniation and those with an additional anomaly were excluded. Cases in which bowel loops were identified within the fetal chest on US while the stomach was intra-abdominal were categorized as having stomach-down CDH. Cases in which bowel loops and the stomach were visualized within the fetal chest on US were categorized as having stomach-up CDH. Prenatal imaging findings and postnatal outcomes were compared between the two groups.

RESULTS

In total, 152 patients with left CDH were initially eligible for inclusion. Seventy-eight patients had surgically confirmed liver herniation and were excluded. Of the 74 included CDH cases without liver herniation, 28 (37.8%) had stomach-down CDH and 46 (62.2%) had stomach-up CDH. Of the 28 stomach-down CDH cases, 10 (35.7%) were referred for a suspected lung lesion. Sixty-eight (91.9%) cases had postnatal outcome data available for analysis. There was no significant difference in median observed-to-expected (o/e) lung-area-to-head-circumference ratio (LHR) between cases with stomach-down CDH and those with stomach-up CDH (41.5% vs 38.4%; P = 0.41). Furthermore, there was no difference in median MRI o/e total lung volume (TLV) between the two groups (49.5% vs 44.0%; P = 0.22). Compared with stomach-up CDH patients, stomach-down CDH patients demonstrated lower median duration of intubation (18 days vs 9.5 days; P < 0.01), median duration of extracorporeal membrane oxygenation (495 h vs 223.5 h; P < 0.05), rate of supplemental oxygen requirement at 30 days of age (20/42 (47.6%) vs 3/26 (11.5%); P < 0.01) and rate of pulmonary hypertension at initial postnatal echocardiography (28/42 (66.7%) vs 9/26 (34.6%); P = 0.01). No neonatal death occurred in stomach-down CDH patients and one neonatal death was seen in a patient with intrathoracic stomach herniation.

CONCLUSIONS

In infants with left CDH without liver herniation, despite similar o/e-LHR and o/e-TLV, those with stomach-down CDH have decreased neonatal morbidity compared to those with stomach herniation. Progressive or variable physiological distension of the stomach over the course of gestation may explain these findings. Stomach-down left CDH is mistaken for a lung mass in a substantial proportion of cases. Accurate prenatal US characterization of CDH is crucial for appropriate prenatal counseling and patient management. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Fetal Intraventricular Hemorrhage in Open Neural Tube Defects: Prenatal Imaging Evaluation and Perinatal Outcomes

BACKGROUND AND PURPOSE

Fetal imaging is crucial in the evaluation of open neural tube defects. The identification of intraventricular hemorrhage prenatally has unclear clinical implications. We aimed to explore fetal imaging findings in open neural tube defects and evaluate associations between intraventricular hemorrhage with prenatal and postnatal hindbrain herniation, postnatal intraventricular hemorrhage, and ventricular shunt placement.

MATERIALS AND METHODS

After institutional review board approval, open neural tube defect cases evaluated by prenatal sonography between January 1, 2013 and April 24, 2018 were enrolled (n = 504). The presence of intraventricular hemorrhage and gray matter heterotopia by both prenatal sonography and MR imaging studies was used for classification. Cases of intraventricular hemorrhage had intraventricular hemorrhage without gray matter heterotopia (n = 33) and controls had neither intraventricular hemorrhage nor gray matter heterotopia (n = 229). A total of 135 subjects with findings of gray matter heterotopia were excluded. Outcomes were compared with regression analyses.

RESULTS

Prenatal and postnatal hindbrain herniation and postnatal intraventricular hemorrhage were more frequent in cases of prenatal intraventricular hemorrhage compared with controls (97% versus 79%, 50% versus 25%, and 63% versus 12%, respectively). Increased third ventricular diameter, specifically >1 mm, predicted hindbrain herniation (OR = 3.7 [95% CI, 1.5-11]) independent of lateral ventricular size and prenatal intraventricular hemorrhage. Fetal closure (n = 86) was independently protective against postnatal hindbrain herniation (OR = 0.04 [95% CI, 0.01-0.15]) and postnatal intraventricular hemorrhage (OR = 0.2 [95% CI, 0.02-0.98]). Prenatal intraventricular hemorrhage was not associated with ventricular shunt placement.

CONCLUSIONS

Intraventricular hemorrhage is relatively common in the prenatal evaluation of open neural tube defects. Hindbrain herniation is more common in cases of intraventricular hemorrhage, but in association with increased third ventricular size. Fetal closure reverses hindbrain herniation and decreases the rate of intraventricular hemorrhage postnatally, regardless of the presence of prenatal intraventricular hemorrhage.

Myelomeningocele sac associated with worse lower-extremity neurological sequelae: evidence for prenatal neural stretch injury?

OBJECTIVE

To determine whether the presence of a myelomeningocele (MMC) sac and sac size correlate with compromised lower-extremity function in fetuses with open spinal dysraphism.

METHODS

A radiology database search was performed to identify cases of MMC and myeloschisis (MS) diagnosed prenatally in a single center from 2013 to 2017. All cases were evaluated between 18 and 25 weeks. Ultrasound reports were reviewed for talipes and impaired lower-extremity motion. In MMC cases, sac volume was calculated from ultrasound measurements. Magnetic resonance imaging reports were reviewed for hindbrain herniation. The association of presence of a MMC sac and sac size with talipes and impaired lower-extremity motion was assessed. Post-hoc analysis of data from the multicenter Management of Myelomeningocele Study (MOMS) randomized controlled trial was performed to confirm the study findings.

RESULTS

In total, 283 MMC and 121 MS cases were identified. MMC was associated with a lower incidence of hindbrain herniation than was MS (80.9% vs 100%; P < 0.001). Compared with MS cases, MMC cases with hindbrain herniation had a higher rate of talipes (28.4% vs 16.5%, P = 0.02) and of talipes or lower-extremity impairment (34.9% vs 19.0%, P = 0.002). Although there was a higher rate of impaired lower-extremity motion alone in MMC cases with hindbrain herniation than in MS cases, the difference was not statistically significant (6.6% vs 2.5%; P = 0.13). Among MMC cases with hindbrain herniation, mean sac volume was higher in those associated with talipes compared with those without talipes (4.7 ± 4.2 vs 3.0 ± 2.6 mL; P = 0.002). Review of the MOMS data demonstrated similar findings; cases with a sac on baseline imaging had a higher incidence of talipes than did those without a sac (28.2% vs 7.5%; P = 0.007).

CONCLUSIONS

In fetuses with open spinal dysraphism, the presence of a MMC sac was associated with fetal talipes, and this effect was correlated with sac size. The presence of a larger sac in fetuses with open spinal dysraphism may result in additional injury through mechanical stretching of the nerves, suggesting another acquired mechanism of injury to the exposed spinal tissue. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.