Does fetoscopic or open repair for spina bifida affect fetal and postnatal growth?

OBJECTIVE

The effect of fetoscopic myelomeningocele (MMC) repair on fetal growth is unknown. Fetal surgery itself and/or exposure to a carbon dioxide (CO₂ ) environment during spina bifida repair may affect placental function and impair fetal growth. Our aim was to assess and compare growth in fetuses, neonates and infants who underwent prenatal fetoscopic or open MMC repair.

METHODS

Fetal biometrics were obtained serially using ultrasound after fetoscopic (n = 32) or open hysterotomy (n = 34) MMC repair in utero at a single institution between November 2011 and July 2017. Measurements obtained during growth scans on initial evaluation prior to surgery, and those taken at 6 weeks post-surgery, were transformed into percentiles and compared between groups. Additional neonatal and infant anthropometric measurements, including weight, length/height and head circumference, were also transformed into percentiles and compared between the groups. The proportions of cases in each group with estimated fetal weight (EFW) or postnatal weight < 10^th and < 3^rd percentiles were calculated and compared. A linear mixed model was used to analyze the serial fetal growth measurements of each parameter, and random intercepts and slopes were used to compare study variables between the study groups. The duration of surgery (skin-to-skin time at fetoscopic and open MMC repair) and duration of CO₂ exposure (fetoscopic repair) were evaluated for any effect on the fetal, neonatal or infant biometric percentiles.

RESULTS

Fetuses which underwent fetoscopic repair had a larger abdominal circumference percentile at referral (57 ± 21 vs 46 ± 23; P = 0.04). There were no other differences between the two groups in fetal biometric percentiles at the time of referral, 6 weeks post-surgery or at birth. There were no differences between groups in EFW percentile or in proportions of cases with birth weight < 10^th and < 3^rd percentiles. Linear mixed-model analysis did not show any significant differences in any fetal growth parameter between the groups over time. There were no significant correlations between duration of surgery or duration of CO₂ exposure and any of the biometric percentiles evaluated. Postnatal growth showed no significant differences between the groups in weight, height or head circumference percentiles, at 6-18, 18-30 or > 30 months of age.

CONCLUSIONS

Babies exposed to fetoscopic or open MMC repair in-utero did not show significant differences in fetal or postnatal growth parameters. These results support the safety of the use of CO₂ gas for fetoscopic surgery. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Congenital Aqueductal Stenosis: Findings at Fetal MRI That Accurately Predict a Postnatal Diagnosis

BACKGROUND AND PURPOSE

Congenital aqueductal stenosis is a common cause of prenatal ventriculomegaly. An accurate diagnosis provides prognostic information and may guide obstetric management. The purpose of this study was to identify specific anatomic findings on prenatal MR imaging that can be used as predictors of congenital aqueductal stenosis.

MATERIALS AND METHODS

Prenatal and postnatal MRIs of fetuses referred to our institution for ventriculomegaly between June 2008 and August 2015 were reviewed. Imaging findings in postnatally confirmed congenital aqueductal stenosis (disease group) were compared with those of ventriculomegaly cases from other causes (control group). Univariate analysis was performed using the Fisher exact test and the Wilcoxon rank test, and multivariate analysis, via the random forest method.

RESULTS

Forty-three cases of ventriculomegaly had a confirmed postnatal diagnosis of congenital aqueductal stenosis. Thirty-two ventriculomegaly cases negative for congenital aqueductal stenosis were included in the control group. Dominant findings associated with an accurate prenatal diagnosis of congenital aqueductal stenosis on multivariate analysis included the following: enlarged inferior third ventricular recesses, enlargement of the lateral ventricles and third ventricle, and an abnormal corpus callosum. Findings that significantly increase the probability of congenital aqueductal stenosis (high positive predictive value) included the following: enlarged third ventricular recesses, aqueduct funneling, hemorrhage in the cerebral aqueduct, ventricular diverticulum, rhombencephalosynapsis, and dystroglycanopathy-related cerebellar dysplasia.

CONCLUSIONS

Our study identified specific characteristics on fetal MR imaging that can be used as predictors of the diagnosis of congenital aqueductal stenosis. Most of these findings are secondary to the obstructive nature of the resulting hydrocephalus. Common associated malformations such as rhombencephalosynapsis and dystroglycanopathies should also increase the suspicion of congenital aqueductal stenosis when present with ventriculomegaly.

Physical activity in osteopenia treatment improved the mass of bones directly and indirectly submitted to mechanical impact

The effect of physical activity in the treatment of osteopenia induced by ovariectomy was studied in 34 two-month-old Wistar female rats. Animals were divided into three groups in which two were formed by ovariectomized (OVX) animals and the other one had sham-operated animals. Group 1, active OVX'd rats; group 2, sedentary OVX'd rats and group 3, sham-operated ones (control). After three months of daily physical activity in a motor-driven treadmill all rats were sacrificed. In order to perform a histomorphometric analysis, long bones, vertebrae, and nasal bone were selected at necropsy. Ovariectomized rats which exercised showed an increased trabecular bone volume, cortical thickness in the long bones and vertebrae and also an increased nasal bone thickness. Physical activity also increased the connection of osteocytes. It was concluded that physical activity in osteopenia treatment increases and restores the mass of bones directly and indirectly submitted to physical impact.