Comparison of brain microstructure after prenatal spina bifida repair by either laparotomy‐assisted fetoscopic or open approach

Abstract

CONTRIBUTIONWhat are the novel findings of this work? Prenatal and postnatal brain microstructure is similar between infants who underwent open hysterotomy and those who had fetoscopic spina bifida repair, and changes seen over time were also comparable between the two groups. These findings support the safety of using CO 2 gas for uterine insufflation during fetoscopic spina bifida repair. What are the clinical implications of this work?The findings of this study add to the body of evidence supporting the use of CO 2 for uterine insufflation in fetoscopic myelomeningocele repair. Fetoscopic techniques are safer for the mother and the fetus than is open repair. As a shift in practice towards fetoscopic repair is expected, evidence for the safety of CO 2 use is of critical relevance. ABSTRACTObjective To compare prenatal and postnatal brain microstructure between infants that underwent fetoscopic myelomeningocele (MMC) repair and those that had open-hysterotomy repair. Methods This was a longitudinal retrospective cohort study of 57 fetuses that met the Management of Myelomeningocele Study (MOMS) trial criteria and underwent prenatal MMC repair, by a fetoscopic (n = 27) or open-hysterotomy (n = 30) approach, atResults There were no differences in GA at surgery or GA/postnatal age at MRI between the groups. No significant differences were observed in ADC values in any of the brain areas assessed between the open-repair and fetoscopic-repair groups at 6 weeks after surgery and in the first year after birth. No differences were detected in the ADC values of the studied areas between the control 88 Sanz Cortes et al. and prenatally repaired groups, except for significantly increased ADC values in the genu of the corpus callosum in the open-hysterotomy and fetoscopic-repair groups. Additionally, there were no differences between the two prenatally repaired groups in the percentage change in ADC values at any of the time intervals analyzed. ConclusionsFetoscopic MMC repair has no detectable effect on brain microstructure when compared to babies repaired using an open-hysterotomy technique. CO 2 insufflation of the uterine cavity during fetoscopy does not seem to have any isolated deleterious effects on fetal brain microstructure.

Prenatal and postnatal MRI findings in open spinal dysraphism following intrauterine repair via open versus fetoscopic surgical techniques

“…It is possible that the lack of variation in third ventricle size prenatally is a reason why this has not been previously reported on; however, third ventricular size is important in the evaluation of aqueductal stenosis, which can coexist in cases of Chiari II malformation . Although there was a significant difference in lateral ventricular size on postnatal brain MRI between the open and fetoscopic repair groups, this can be explained by the differences in selection criteria in our cohort as one recently published study described no significant difference in ventricular size between the two groups . The only other difference we observed between the two groups postnatally was a higher incidence of subependymal grey matter heterotopias in the open repair group.…”

“…There is now a growing body of literature describing both the fetal and postnatal MRI findings in this patient population, not only describing changes between presurgical and postsurgical findings but also the expected postoperative imaging appearance in these patients. There are very few imaging descriptions in the fetoscopic repair population, with one study examining postoperative growth parameters and a second study from the same group examining diffusion characteristics in patients undergoing fetoscopic repair of OSD . We present our imaging data in patients with OSD undergoing fetal surgery as well as our initial experience with preoperative and postoperative fetal MRI imaging and patients undergoing prenatal repair of OSD by both the open and the fetoscopic techniques.…”

Fetoscopic myelomeningocoele closure: Is the scientific evidence enough to challenge the gold standard for prenatal surgery?

“…Reassuringly, there is currently no evidence of immediate adverse effects on cerebral development based on postnatal MRI. 25 The initial high intraoperative complications and perinatal mortality observed with the percutaneous approach have improved in the latest experience published by the two most experienced groups in the world. [7][8][9]16,26 In the most recent series, excluding cases from learning curves, the procedure was technically feasible in almost all cases.…”

In case you missed it: The Prenatal Diagnosis editors bring you the most significant advances of 2019

“…While the debate continues over whether or not minimally invasive surgery is equally neuroprotective as open surgery and which surgical techniques have the least prematurity risk, it is worth considering the experience required to complete the learning curve for prenatal spina bifida repair. Centres performing high volumes of in‐utero surgery report that it takes up to 30 (open) or 60 (fetoscopy) procedures to become proficient .…”

“…40,41 Dry CO 2 also has an effect on the fetal membranes but, based on biomechanical studies published this year, heating and humidifying the gas may also reduce the risk for membrane rupture. 42,43 While the debate continues over whether or not minimally invasive surgery is equally neuroprotective as open surgery and which surgical techniques have the least prematurity risk, [44][45][46] it is worth considering the experience required to complete the learning curve for prenatal spina bifida repair. Centres performing high volumes of in-utero surgery report that it takes up to 30 (open) or 60 (fetoscopy) procedures to become proficient.…”