Percutaneous fetoscopic spina bifida repair: effect on ambulation and need for postnatal cerebrospinal fluid diversion and bladder catheterization

Proof of concept testing of a vascular closure device for use in fetal surgery

OBJECTIVE

Prior clinical findings have demonstrated that maternal laparotomy with trans-amniotic trans-uterine suturing of the fetoscopic port site during in utero myelomeningocele repair reduces the risk of membrane rupture. However, due to laparotomy-associated morbidity, we aimed to explore the feasibility of using a vascular closure device for percutaneous trans-amniotic trans-uterine suturing.

METHODS

This IRB and IACUC-exempt study utilized 2 strategies for proof-of-concept testing of using the Abbott Perclose™ ProStyle™ Device for suture placement; 1. Ultrasound guided application on a high fidelity maternal abdominal uterus model used for fetal procedures and 2. Placement under direct visualization with sheep undergoing cesarean delivery for other research purposes. In the high-fidelity uterus model, the Abbott Perclose™ ProStyle™ device was used to place a transuterine/transamniotic stitch with accompanying video recording of the approach (https://go.screenpal.com/watch/cZfhoDVsYvW password: perclose). Regarding the second approach, at the time of a cesarean section, 12 French Checkflo® cannulas were inserted into the sheep amniotic space via different approaches: (1) Seldinger technique, (2) Seldinger technique insertion of Checkflo® cannula and subsequent use of the Abbott Perclose™ ProStyle™ device to suture the port site after check flow removal, (3) Abbott Perclose™ ProStyle™ device utilized in what is described as a "pre-close" technique, where prior to cannula placement, trans-uterine trans-amniotic stitches are placed followed by the insertion of a 12 French Checkflo® cannula over the same guidewire. Samples of the sutured uterine wall were sent to pathology and H&E staining was performed to assess uterine hole closure and amnion-to-uterus fixation.

RESULTS

The high-fidelity model confirmed that the Perclose™ ProStyle™ Device was easily visualized by ultrasound and suture deployment was without complication. In the animal model, the Perclose™ ProStyle™ device effectively sutured the amnion to the uterus in both the pre- and post-close approach. The pre-close technique achieved better amnion-to-uterus approximation and more appropriate uterine hole closure. H&E staining revealed that without suturing, amnion separation from the chorion layer occurred, and the uterine hole persisted. The post-close technique showed partial connection between the amnion and chorion, but inadequate uterine hole closure with amnion shift into the defect. Optimal closure, with secure amnion-to-chorion fixation and uterine closure, was achieved through the pre-close technique.

CONCLUSION

The Abbott Perclose™ ProStyle™ Device seems to be a feasible device for use of uterine port closure in maternal-fetal surgery, larger animal studies with mid-pregnancy application are needed to further validate or refute these findings.

Ultrasound assessment of bladder and motor function in fetuses with open spina bifida: cohort study

OBJECTIVES

Open spina bifida (OSB) is associated with lower limb and bladder dysfunction. We documented bladder function and lower limb motor function on ultrasound throughout gestation in a cohort of fetuses with OSB. The association of the prenatal findings with postnatal dysfunction was investigated, along with the impact of talipes on pre- and postnatal motor function.

METHODS

A prospective cross-sectional cohort study was performed including all fetuses with isolated OSB, which were assessed at the University Hospitals Leuven between July 2015 and December 2019. The anatomical level of the lesion was determined on three-dimensional ultrasound. Bladder volumes were also measured on three-dimensional ultrasound and filling-voiding changes (flow) were calculated and compared to gestational-age-matched control fetuses imaged for this study (matched 1:1). The fetal motor function level was determined on ultrasound based on joint movement of the hip, knee, ankle and toes. Postnatal bladder function was assessed by questionnaire and cystography at 1 year of age. The predictive ability of prenatal anatomical and functional levels for postnatal lower limb function was assessed. Lastly, the presence of talipes was assessed as a prognostic factor.

RESULTS

We included 122 examinations from 69 OSB fetuses. Bladder volumes were smaller in fetuses with OSB compared to controls and the difference increased with advancing gestational age. There was no association of bladder volume and urinary flow with the level of the lesion, nor was there a measurable effect of prenatal surgery on fetal bladder volume. Postnatal urinary reflux was more likely in children with a smaller bladder volume and lower urinary flow rate at 24 weeks' gestation. Lower limb motor dysfunction was more frequent at higher gestational ages. In-utero motor function was a better predictor of postnatal motor function than the anatomical level of the lesion in fetuses that underwent surgery. Fetuses with talipes performed four levels worse postnatally compared to fetuses without talipes, despite a similar anatomical level of the lesion.

CONCLUSION

In OSB, prior to fetal surgery, bladder volume and urinary flow are already abnormal from early in gestation, independent of the level of the lesion, and may be predictive of postnatal urinary reflux. Motor function impairment can be demonstrated prenatally and is a better predictor of postnatal motor dysfunction than the prenatal anatomical level of the lesion. The presence of talipes adversely impacts postnatal motor function. © 2025 International Society of Ultrasound in Obstetrics and Gynecology.

Maternal-fetal surgery for myelomeningocele longitudinal follow-up model: Mitigation of care fragmentation through care coordination and outcomes reporting

PurposeFollowing the Global Health Symposium at the Spina Bifida World Congress in 2023, the purpose of this work is to provide a historical overview and a state-of-the-art update on the current global practice of myelomeningocele (MMC) closure and to highlight the importance of care coordination and outcomes reporting to mitigate care fragmentation through a multidisciplinary approach.MethodsPanelists from the Spina Bifida World Congress Global Health Symposium reviewed their institutions' history and experience with risk for fragmentation of care following prenatal repair and proposed solutions to address fragmentation of care.ResultsNew and rapidly evolving in-utero approaches to MMC repair are increasingly accessible for patients worldwide but bring more complexity to follow-up care. There is a consensus that unifying multidisciplinary practices and evaluations across institutions and countries will help make care coordination more comprehensive and longitudinal, and that meeting these standards may decrease care fragmentation.ConclusionRegardless of the open spina bifida repair technique, longitudinal follow-up must be established after fetal surgery, not only for the optimal care of individual patients but also to mitigate care fragmentation, transparently evaluate and compare techniques (for example, through the North American Fetal Therapy Network, the National Spina Bifida Patient Registry, etc.), engage health care professionals, and provide evidence-based multidisciplinary care.

Gestational age at birth varies by surgical technique in prenatal open spina bifida repair: a systematic review and meta-analysis

OBJECTIVE

Prenatal repair of open spina bifida has become well-established. Several surgical approaches have emerged, each focused on optimizing outcomes while minimizing risks. This study aims to compare the gestational age at delivery following the various surgical techniques.

DATA SOURCES

This systematic review and meta-analysis synthesizes data from 37 studies between 2010 and 2023.

STUDY ELIGIBILITY CRITERIA

Eligible studies included pregnant patients diagnosed with open spina bifida who underwent the following intrauterine repair techniques: open repair, mini-hysterotomy, laparotomy-assisted fetoscopic repair, and percutaneous fetoscopic repair.

STUDY APPRAISAL AND SYNTHESIS METHODS

The primary outcome investigated was gestational age at delivery, while secondary outcomes were preterm premature rupture of membranes, vaginal birth, and perinatal mortality. The programming language software R (version 4.0.5) was used to execute the analysis.

RESULTS

In this meta-analysis, 2333 prenatal repair of open spina bifida procedures arising from 14 countries were analyzed. Of these, open repair accounted for 65.7%, mini-hysterotomy accounted for 14.4%, laparotomy-assisted fetoscopic repair accounted for 5.36%, and percutaneous fetoscopic repair accounted for 14.6%. The subgroup analyses revealed a nonsignificant mean gestational age at birth: 34+1 weeks for open repair, 34+2 weeks for mini-hysterotomy, 35+3 weeks for laparotomy-assisted repair, and 32+3 weeks for percutaneous fetoscopic repair (P=.26). While the gestational age at birth was not different, there were significant differences (P<.01) in pooled proportions of preterm premature rupture of membranes and preterm birth by surgical approach (overall rates: 75% and 30% respectively). Vaginal birth rates had significant subgroup differences (P<.01), with the laparotomy-assisted fetoscopic group more likely to have vaginal deliveries (0.02, 0.04, 0.49, 0.18 for open, mini, laparotomy, and percutaneous, respectively).

CONCLUSION

The advanced secondary Bayesian analysis of data from this meta-analysis suggests that the mean gestational age at birth may differ among the 4 surgical techniques for prenatal repair of open spina bifida, with a potential advantage for the decrease in preterm births associated with a laparotomy-assisted approach. However, these findings should be interpreted cautiously, and further direct comparison studies are needed to confirm these observations.

Anesthetic management for fetal surgery: lessons from a single-center experience (2019-2023)

BACKGROUND

Fetal surgery presents distinctive anesthetic challenges due to the need to balance maternal and fetal safety. This retrospective study evaluates the anesthetic management strategies used at a single center for various fetal interventions, including fetoscopic laser photocoagulation, fetal endoluminal tracheal occlusion, bipolar cord coagulation, and fetoscopic spina bifida repair.

METHODS

We reviewed 195 fetal procedures performed between 2019 and 2023 at Rabin Medical Center. Data collected included maternal and fetal characteristics, anesthetic techniques (spinal, combined spinal-epidural, general), intraoperative hypotension, and perioperative complications. We examined the evolution of anesthetic practice, particularly focusing on hemodynamic management and postoperative pain control.

RESULTS

Spinal anesthesia was increasingly preferred for shorter procedures such as fetoscopic laser photocoagulation and bipolar cord coagulation, while general anesthesia was used exclusively for spina bifida repair. Intraoperative hypotension was a significant issue, leading to the implementation of prophylactic phenylephrine infusions, which improved blood pressure control. A shift from volatile anesthesia to total intravenous anesthesia in spina bifida repair resulted in fewer complications, including reduced bleeding. Postoperative pain management was optimized with a multimodal approach, improving pain scores.

CONCLUSIONS

This study underscores the importance of tailoring anesthetic techniques to the specific fetal surgery. Key improvements in hypotension management, adopting total intravenous anesthesia for complex surgeries, and optimized postoperative pain control have contributed to better maternal and fetal outcomes. Ongoing reassessment and adaptation of anesthetic protocols remain critical as fetal surgery evolves.

The Intrauterine Treatment of Open Spinal Dysraphism

BACKGROUND

Open spinal dysraphism is a congenital malformation that causes major morbidity. Its consequences include sensory and motor impairment as well as bladder- and bowel dysfunction. It is often also associated with prenatal ventriculomegaly, which, in turn, necessitates postnatal treatment with a ventriculoperitoneal shunt in approximately 80% of cases. Prenatal therapy with coverage of neural tube defect can reduce the shunt rate and preserve motor function. In this review, we describe the different surgical procedures and their outcomes.

METHODS

This review is based on publications that were retrieved by a selective literature search in the MEDLINE, Web of Science, EMBASE, Scopus, and Cochrane databases, employing pertinent keywords. Studies of all types (except case reports) that were published in English or German in the period 2010-2024 were included.

RESULTS

The randomized, controlled MOMS trial showed that intrauterine surgery for defect closure resulted in less progressive neural tissue damage than postnatal surgery and reduced the need for shunting by approximately half (40% vs. 82%). Since the publication of these results, various prenatal surgical procedures have been established, including hysterotomy-assisted, percutaneous fetoscopic, and laparotomy-assisted fetoscopic closure. The individual surgical methods yield comparable results in terms of motor function and shunt rate. A problem with these procedures is that they increase the likelihood of preterm birth, to an extent that varies from one type of procedure to another.

CONCLUSION

Prenatal surgery improves motor function and reduces the shunt rate but long-term outcomes beyond adolescence are still lacking. Transparent and interdisciplinary counseling is essential in prenatal communication to inform parents not only about the potential benefits of this treatment, but also about its limitations and risks.

Sleep-related breathing disorders in infants with spina bifida repaired prenatally and postnatally

STUDY OBJECTIVES

Advances in prenatal repair of myelomeningocele have improved outcomes involving different organ systems. There are limited data on respiratory outcomes following prenatal surgical repair. We hypothesize there is no difference in respiratory outcomes between patients with spina bifida who have undergone prenatal vs postnatal repair.

METHODS

We performed a retrospective study of 46 infants < 1 year with spina bifida seen at Children's Hospital Los Angeles from 2004-2022. Demographic data, timing of closure, neonatal course, Chiari II malformation, ventriculoperitoneal shunt, polysomnography results, and need for supplemental oxygen were collected. Unpaired t test and χ2 test were used to analyze results.

RESULTS

A total of 31/46 had prenatal repair of myelomeningocele; average age at repair was 27 weeks postconception. Average age at postnatal repair was 37 weeks postconception. There was no difference in age at polysomnography. There was no difference in Chiari II malformation presence (P = .61). Sixty pecent of patients with postnatal repair and 23% in the prenatal group underwent ventriculoperitoneal shunt placement (P = .01). There was no difference in polysomnography findings between the 2 groups: central apnea index (P = .11), obstructive apnea-hypopnea index (P = .64), average oxygen saturation baseline (P = .91), average oxygen saturation nadir (P = .17), average end-tidal carbon dioxide baseline (P = .87), and average end-tidal carbon dioxide maximum (P = .54). There were no significant differences in the proportion of patients on supplemental oxygen (P = .25), central sleep apnea or obstructive sleep apnea between groups.

CONCLUSIONS

Patients with spina bifida who have undergone closure of neural tube defect have persistent central apneas, obstructive apneas, and significant hypoxemia. There were no differences in the frequency or severity of sleep-disordered breathing in those with prenatal repair vs postnatal repair.

CITATION

Stark KG, Wang RY, Smith KA. Sleep-related breathing disorders in infants with spina bifida repaired prenatally and postnatally. J Clin Sleep Med. 2024;20(10):1579-1583.

Maternal and perinatal outcomes of minimally invasive fetal surgeries: experience from two reference centers in Rio de Janeiro, Brazil

BACKGROUND

Concerns regarding high open surgery-related maternal morbidity have led to improvements in minimally invasive fetal surgeries.

OBJECTIVE

To analyze the perinatal and maternal outcomes of minimally invasive fetal surgery performed in Rio de Janeiro, Brazil.

DESIGN AND SETTING

Retrospective cohort study conducted in two tertiary reference centers.

METHODS

This retrospective descriptive study was conducted using medical records from 2011 to 2019. The outcomes included maternal and pregnancy complications, neonatal morbidity, and mortality from the intrauterine period to hospital discharge.

RESULTS

Fifty mothers and 70 fetuses were included in this study. The pathologies included twin-twin transfusion syndrome, congenital diaphragmatic hernia, myelomeningocele, lower urinary tract obstruction, pleural effusion, congenital upper airway obstruction syndrome, and amniotic band syndrome. Regarding maternal complications, 8% had anesthetic complications, 12% had infectious complications, and 6% required blood transfusions. The mean gestational age at surgery was 25 weeks, the mean gestational age at delivery was 33 weeks, 83% of fetuses undergoing surgery were born alive, and 69% were discharged from the neonatal intensive care unit.

CONCLUSION

Despite the small sample size, we demonstrated that minimally invasive fetal surgeries are safe for pregnant women. Perinatal mortality and prematurity rates in this study were comparable to those previously. Prematurity remains the most significant problem associated with fetal surgery.

The impact of a biocellulose-based repair of fetal open spina bifida on the need to untether the cord: is it time to unify techniques for prenatal repair?

OBJECTIVE

To report the need for cord untethering after prenatal repair of open spina bifida using a unique biocellulose-based technique performed at a later gestational age.

METHODS

An observational cohort study was conducted to determine the incidence of tethered cord syndrome. Between May 2013 and May 2022, we performed 172 procedures using the percutaneous fetoscopic approach in fetuses at 26-28 weeks of gestation. After placode dissection, a biocellulose patch was placed to cover the placode, a myofascial flap (when possible) was dissected, and the skin was closed. Owing to death or loss to follow-up, 23 cases were excluded. Cord tethering syndrome was defined as symptoms of medullary stretching, and the infants were evaluated and operated on by local neurosurgeons after an magnetic resonance imaging examination. Infants over 30-month had ambulation and neurodevelopment evaluations (PEDI scale).

RESULTS

Among 172 cases operated at a median gestational age of 26.7 weeks and delivered at 33.2 weeks, 149 cases were available for postnatal follow-up, and cord untethering was needed in 4.4% of cases (6/136; excluding 13 cases younger than 12 months). Cerebrospinal fluid diversion and bladder catheterization were needed in 38% and 36% of cases, respectively. Of the 78 cases evaluated at 30 months, 49% were ambulating independently, and 94% had normal social function.

CONCLUSION

The biocellulose-based technique was associated with a low rate of cord tethering, wich may be attributed to the lack of the duramater suture during prenatal repair, the formation of a neoduramater and/or later gestational age of surgery.

Exteriorization of the uterus reduces fetoscopic cannula-induced stress and strain: A finite element model analysis

OBJECTIVE

To estimate stresses and strains in the uterine wall and fetal membranes with single/multi-port fetoscopy, simulating either a percutaneous access or via exteriorized uterus.

STUDY DESIGN

Finite element models based on anatomical dimensions, material properties and boundary conditions were created to simulate stresses, strains and displacements on the uterine wall and fetal membranes during simulated fetal surgery either via exteriorized uterus or percutaneous approach, and with one or three cannulas. Clinically, we measured the anatomical layer thickness and cannula entry point displacement in patients undergoing single port percutaneous fetoscopy.

RESULTS

Simulations demonstrate that single port percutaneous fetoscopy increases stress on the fetal membranes (+105%, 128 to 262 kPa) and uterine wall (+115%, 0.89 to 1.9 kPa) compared to exteriorized uterine access. Using three ports increases stress by 110% (148 to 312 kPa) on membranes and 113% (1.08 to 2.3 kPa) on uterine wall. Finite Element Method showed 0.75 cm uterine entry point displacement from the cutaneous entry, while clinical measurements demonstrated displacement of more than double (1.69 ± 0.58 cm), suggesting modeled measurements may be underestimations.

CONCLUSION

The stresses and strains on the fetal membranes and uterus are double as high when entering percutaneously than via an exteriorized uterus. Based on what can be clinically measured, this may be an underestimation.

Revisiting MOMS criteria for prenatal repair of spina bifida: upper gestational-age limit should be raised and assessment of prenatal motor function rather than anatomical level improves prediction of postnatal function

OBJECTIVES

To determine if the lower-extremity neurological motor function level in fetuses with open spina bifida deteriorates within the 4-week interval between a first prenatal motor assessment at around 22 weeks of gestation and a second evaluation, prior to 'late' prenatal surgery, defined as surgery at 26-28 weeks and, in certain situations, up to 30 weeks, and to assess the association between prenatal presurgical motor-function level, anatomical level of the lesion and postnatal motor-function level.

METHODS

This was a two-center cohort study of 94 singleton fetuses with open spina bifida which underwent percutaneous repair using the skin-over-biocellulose for antenatal fetoscopic repair (SAFER) technique between December 2016 and January 2022. All women underwent two prenatal systematic ultrasound evaluations, approximately 4 weeks apart, with the second one being performed less than 1 week before surgery, and one postnatal evaluation via physical examination within 2 months of birth. Motor-function classification was from spinal level T12 to S1, according to key muscle function. Each leg was analyzed separately; in case of discrepancy between the two legs, the worst motor-function level was considered for analysis. Motor-function-level evaluations were compared with each other and with the anatomical level as observed on ultrasound. Independent predictors of a postnatal reduction in motor-function level were assessed using a logistic regression model.

RESULTS

Prenatal motor-function level was assessed at a median gestational age of 22.5 (interquartile range (IQR), 20.7-24.3) and 26.7 (IQR, 25.4-27.3) weeks, with a median interval of 4.0 (IQR, 2.4-6.0) weeks. The median gestational age at surgery was 27.0 (IQR, 25.9-27.6) weeks and the postnatal examination was at median age of 0.8 (IQR, 0.3-5.4) months. There was no significant difference in motor-function level between the two prenatal evaluations (P = 0.861). We therefore decided to use the second prenatal evaluation for comparison with postnatal motor function and anatomical level. Overall, prenatal and postnatal motor function evaluations were significantly different from the anatomical level (preoperative assessment, P = 0.0015; postnatal assessment, P = 0.0333). Comparing prenatal with postnatal motor-function level, we found that 87.2% of babies had similar or improved motor function compared with that prior to prenatal surgery. On logistic regression analysis, lower anatomical level of defect and greater difference between anatomical level and prenatal motor-function level were identified as independent predictors of postnatal motor function (odds ratio, 0.237 (95% CI, 0.095-0.588) (P = 0.002) and 3.44 (95% CI, 1.738-6.813) (P < 0.001), respectively).

CONCLUSIONS

During a 4-week interval between first ultrasound evaluation and late fetal surgical repair of open spina bifida, motor function does not change significantly, suggesting that late repair, ≥ 26 weeks, does not impact negatively on motor-function outcome. Compared with the anatomical level of the lesion, preoperative neurological motor-function assessment via ultrasound is more predictive of postnatal motor function, and should be included in preoperative counseling. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Biocellulose patch technique for fetoscopic repair of open spina bifida in twin pregnancy

OBJECTIVES

Twin pregnancy is currently an exclusion criterion for prenatal repair of open spina bifida (OSB). The main objective of this study was to report on our experience of treating twin pregnancies with OSB using the skin-over-biocellulose for antenatal fetoscopic repair (SAFER) technique. We also discuss reconsideration of the current exclusion criteria for fetal OSB repair.

METHODS

Eight fetuses with OSB from seven twin pregnancies underwent successful prenatal repair. Six pregnancies were dichorionic diamniotic with only one twin affected, and one was monochorionic diamniotic with both twins affected. Percutaneous fetoscopy was performed under CO2 insufflation of the sac of the affected twin. Neurosurgical repair was performed using a biocellulose patch to protect the placode, with the skin sutured to hold the patch in place, with or without a myofascial flap. Neurodevelopment was assessed using the pediatric evaluation of disability inventory scale in babies older than 6 months of adjusted age, whereas the Alberta scale was used for babies younger than 6 months of adjusted age.

RESULTS

All 14 fetuses were liveborn and none required additional repair. Gestational age at surgery ranged from 27.3 to 31.1 weeks, and gestational age at birth ranged from 31.6 to 36.0 weeks. Four out of eight affected twins developed sepsis, but had a good recovery. No sequela of prematurity was found in any of the unaffected twins. Short-term neurodevelopment was normal in all evaluated unaffected twins (5/5) and in all but one affected twins (7/8). In the affected group, only one baby required ventriculoperitoneal shunt placement.

CONCLUSIONS

Prematurity is frequent after fetal surgery, and the risk is increased in twin pregnancy. Nevertheless, prenatal surgery using the SAFER technique is feasible, with low risk to both twins and their mother when performed by a highly experienced team. Long-term cognitive assessment of the unaffected twin is needed. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Implementation and Assessment of a Laparotomy-Assisted Three-Port Fetoscopic Spina Bifida Repair Program

Open spina bifida (OSB) is a congenital, non-lethal malformation with multifactorial etiology. Fetal therapy can be offered under certain conditions to parents after accurate prenatal diagnostic and interdisciplinary counseling. Since the advent of prenatal OSB surgery, various modifications of the original surgical techniques have evolved, including laparotomy-assisted fetoscopic repair. After a two-year preparation time, the team at the University of Giessen and Marburg (UKGM) became the first center to provide a three-port, three-layer fetoscopic repair of OSB via a laparotomy-assisted approach in the German-speaking area. We point out that under the guidance of experienced centers and by intensive multidisciplinary preparation and training, a previously described and applied technique could be transferred to a different setting.

Prenatal predictors of need for cerebrospinal fluid diversion in infants following prenatal repair of open spina bifida; systematic review and meta-analysis

OBJECTIVE

This study aimed to investigate prenatal predictors of the need for cerebrospinal fluid diversion in infants following prenatal repair of open spina bifida.

DATA SOURCES

A systematic search was performed to identify relevant studies published from inception until June 2022 in the English language using the databases PubMed, Scopus, and Web of Science.

STUDY ELIGIBILITY CRITERIA

We included retrospective and prospective cohort studies and randomized controlled trials reporting on prenatal repair of open spina bifida.

METHODS

The random-effects model was used to pool the mean differences or odds ratios and the corresponding 95% confidence intervals. Heterogeneity was assessed using the I2 value.

RESULTS

A total of 9 studies including 948 pregnancies undergoing prenatal repair of open spina bifida were included in the final analysis. Prenatal factors that were significantly associated with the need for postnatal cerebrospinal fluid diversion were gestational age at surgery ≥25 weeks (odds ratio, 4.2; 95% confidence interval, 1.8-9.9; I2=54%; P=.001), myeloschisis (odds ratio, 2.2; 95% confidence interval, 1.1-4.1; I2=0.0%; P=.02), preoperative lateral ventricle width ≥15 mm (odds ratio, 4.5; 95% confidence interval, 2.9-6.9; I2=0.0%; P<.0001), predelivery lateral ventricle width (mm) (mean difference, 8.3; 95% confidence interval, 6.4-10.2; I2=0.0%; P<.0001), and preoperative lesion level at T12-L2 (odds ratio, 2.5; 95% confidence interval, 1.03-6.3; I2=68%; P=.04). Factors that significantly reduced the need for postnatal shunt placement were gestational age at surgery <25 weeks (odds ratio, 0.3; 95% confidence interval, 0.15-0.6; I2=67%; P=.001) and preoperative lateral ventricle width <15 mm (odds ratio, 0.3; 95% confidence interval, 0.2-0.4; I2=0.0%; P<.0001).

CONCLUSION

This study demonstrated that among fetuses that underwent surgical repair of open spina bifida, having gestational age at surgery of ≥25 weeks, preoperative lateral ventricle width of ≥15 mm, myeloschisis lesion type, and preoperative lesion level above L3 was predictive of the need for cerebrospinal fluid diversion during the first year of life.

Prenatal repair of gastroschisis using partial carbon dioxide insufflation fetoscopy: lessons learned

We report the long-term outcomes of a case of prenatal gastroschisis repair using a fully percutaneous fetoscopic approach with partial carbon dioxide insufflation. Surgery was performed as an experimental procedure before the scheduled elective birth. The fetal intestines were successfully returned to the abdominal cavity without any fetal or maternal complications. Ultrasonography performed 24 hours later revealed bowel peristalsis and no signs of fetal distress. After 48 hours, partial extrusion of the small bowel was observed, and the fetus was delivered. Gastroschisis repair was immediately performed upon delivery using the EXIT-like procedure as per our institutional protocol. The newborn did not require assisted mechanical ventilation, was discharged at 14 days of age and was then exclusively breastfed. At 3-year follow-up, the patient had no associated gastroschisis-related complications. This is the first case of prenatal repair of gastroschisis, which provides baseline knowledge for future researchers on the potential hurdles and management of prenatal repair.

Local host response of commercially available dural patches for fetal repair of spina bifida aperta in rabbit model

OBJECTIVE

Fetal surgery for spina bifida aperta (SBA) by open hysterotomy typically repairs anatomical native tissue in layers. Increasingly, fetoscopic repair is performed using a dural patch followed by skin closure. We studied the host response to selected commercially available patches currently being used in a fetal rabbit model for spina bifida repair.

METHODS

SBA was surgically induced at 23-24 days of gestation (term = 31 days). Fetal rabbits were assigned to unrepaired (SBA group), or immediate repair with Duragen™ or Durepair™. Non-operated littermates served as normal controls. At term, spinal cords underwent immunohistochemical staining including Nissl and glial fibrillary acidic protein. We hypothesized that spinal cord coverage with a dural patch and skin closure would preserve motor neuron density within the non-inferiority limit of 201.65 cells/mm² and reduce inflammation compared to unrepaired SBA fetuses.

RESULTS

Motor neuron density assessed by Nissl staining was conserved both by Duragen (n = 6, 89.5; 95% CI -158.3 to -20.6) and Durepair (n = 6, 37.0; 95% CI -132.6 to -58.5), whereas density of GFAP-positive cells to quantify inflammation was lower than in unrepaired SBA-fetuses (SBA 2366.0 ± 669.7 cells/mm² vs. Duragen 1274.0 ± 157.2 cells/mm² ; p = 0.0002, Durepair 1069.0 ± 270.7 cells/mm² ; p < 0.0001).

CONCLUSIONS

Covering the rabbit spinal cord with either Duragen or Durepair followed by skin closure preserves motor neuron density and reduces the inflammatory response.

Advances in Fetal Surgical Repair of Open Spina Bifida

Spina bifida remains a common congenital anomaly of the central nervous system despite national fortification of foods with folic acid, with a prevalence of 2-4 per 10,000 live births. Prenatal screening for the early detection of this condition provides patients with the opportunity to consider various management options during pregnancy. Prenatal repair of open spina bifida, traditionally performed by the open maternal-fetal surgical approach through hysterotomy, has been shown to improve outcomes for the child, including decreased need for cerebrospinal fluid diversion surgery and improved lower neuromotor function. However, the open maternal-fetal surgical approach is associated with relatively increased risk for the patient and the overall pregnancy, as well as future pregnancies. Recent advances in minimally invasive prenatal repair of open spina bifida through fetoscopy have shown similar benefits for the child but relatively improved outcomes for the pregnant patient and future childbearing.

Intrauterine closure of myelomeningocele defects with primary linear repair versus bipedicle fasciocutaneous flaps: a post-MOMS cohort study with long-term follow-up

OBJECTIVE

The objective of this study was to determine the effects of in utero bipedicle flaps on maternal-fetal morbidity/mortality, the need for CSF diversion, and long-term functional outcomes.

METHODS

Eighty-six patients who underwent fetal myelomeningocele repair from 2011 to 2021 at a single institution were reviewed. Primary outcomes included intrauterine fetal demise, postnatal death, postnatal myelomeningocele repair dehiscence, and CSF diversion by final follow-up.

RESULTS

The cohorts were no different with regard to race, ethnicity, maternal age at fetal surgery, body mass index, gravidity, parity, gestational age at fetal surgery, estimated fetal weight at fetal surgery, or fetal lesion level. Of the 86 patients, 64 underwent primary linear repair and 22 underwent bipedicle flap repair. There were no significant differences in rates of intrauterine fetal demise, postnatal mortality, midline repair site dehiscence, or the need for CSF diversion by final follow-up. Operative times were longer (32.5 vs 18.7 minutes, p < 0.001) and gestational age at delivery was lower (232 vs 241 days, p = 0.01) in the bipedicle flap cohort, but long-term functional outcomes were not different.

CONCLUSIONS

Analysis of the total cohort affirms the long-term benefits of fetal myelomeningocele repair. In utero bipedicle flaps are safe and can be used for high-tension lesions without increasing perioperative risks to the mother or fetus. In utero flaps preserve the long-term benefits seen with primary linear repair and may expand inclusion criteria for fetal repair, providing life-changing care for more patients.

Fetal Neurosurgical Interventions for Spinal Malformations, Cerebral Malformations, and Hydrocephalus: Past, Present, and Future

In this article we review the last 40 years of progress in fetal neurosurgery with special attention to current controversies and upcoming challenges in the field. We surveyed the published literature describing prenatal interventions for spinal malformations, cerebral malformations, and hydrocephalus. Even the most mature treatment paradigm, intrauterine repair of myelomeningocele, stands to benefit from advances in imaging and therapeutic modalities to improve patient selection, refine surgical techniques, validate novel biologic therapies, and streamline postoperative patient care. Other conditions under evaluation include congenital cerebral malformations, such as encephalocele, cerebrovascular malformations, and hydrocephalus. We describe cross-cutting needs for advances in fetal neuroimaging, basic disease models and new therapeutic devices to support further progress across various neurosurgical conditions affecting patients during the fetal period.

Myelomeningocele Including Fetal Prescription

Myelomeningocele (MMC) is one of the most common birth defects, affecting 0.2 to 0.4 per 1,000 live births in the United States. The most strongly associated risk factor is low folate level in pregnancy. For this reason, 0.4- to 1.0-mg supplementation with folic acid is recommended in all pregnancies, and high-risk pregnancies are recommended to supplement with 4.0 mg of folic acid daily. The mechanism behind the development of MMC is believed to be failure of the caudal end of the neural tube to close during primary neurulation. Screening for MMC is achieved by using α-fetoprotein levels in maternal serum or amniocentesis in the first and second trimesters of pregnancy. Ultrasonography and fetal magnetic resonance imaging are used to confirm the presence of MMC as well as the location and size of the defect. Based on the results of the Management of Myelomeningocele Study, fetal repair is performed between 23 weeks and 25 weeks and 6 days of gestational age for appropriate candidates. Postnatal repair is more common and is performed 24 to 72 hours after birth. In general, patients with lesions at lower anatomical levels have a better prognosis. Most children with MMC will have neurogenic bladder and bowel dysfunction that affect the patient's and the caregiver's quality of life. Patients with higher levels of mobility, better familial support, and higher economic status report improved quality of life compared with other patients with MMC.

Percutaneous/mini-laparotomy fetoscopic repair of open spina bifida: a novel surgical technique

Open spina bifida (OSB) is the most common congenital anomaly of the central nervous system compatible with life. Prenatal repair of open spina bifida via open maternal-fetal surgery has been shown to improve postnatal neurological outcomes, including reducing the need for ventriculoperitoneal shunting and improving lower neuromotor function. Fetoscopic repair of OSB minimizes the maternal risks while providing similar neurosurgical outcomes to the fetus. Two fetoscopic techniques are currently in use: (1) the laparotomy-assisted approach, and (2) the percutaneous approach. The laparotomy-assisted fetoscopic technique appears to be associated with less risk of preterm birth compared to the percutaneous approach. However, the percutaneous approach avoids laparotomy and uterine exteriorization, and is associated with less anesthesia risk and improved maternal post-surgical recovery. The purpose of this paper is to describe our experience with a novel surgical approach, which we call percutaneous/mini-laparotomy fetoscopy (PML), in which access to the uterus for one of the ports is done via a mini-laparotomy, while the other ports are inserted percutaneously. This technique draws on the benefits of both the laparotomy-assisted and the percutaneous techniques, while minimizing their drawbacks. This surgical approach may prove invaluable in the prenatal repair of open spina bifida as well as other complex fetal surgical procedures.

Myelomeningocele Surgery over the 10 Years Following the MOMS Trial: A Systematic Review of Outcomes in Prenatal versus Postnatal Surgical Repair

Background and Objectives: Myelomeningocele is the most severe form of spina bifida, a congenital neural tube defect arising from an incomplete neural tube closure during early development with damage worsening with advancing gestational age. The Management of Myelomeningocele Study (MOMS) Trial proved that surgery performed before 26 weeks of gestation significantly improved the prognosis, significantly changing treatment paradigms. This article aims to provide a review of the changes and updates in spina bifida repair over the 10-year period following the MOMS Trial. Material and methods: We performed a systematic review in the PubMed and Cochrane databases as well as a hand-search of high-impact journals using the reference list of all identified articles, searching for randomized controlled trials and observational studies. Results: We identified 27 articles published between 2011 and 2021 that fulfilled the inclusion criteria and review them in the present study. Conclusions: With growing experience and with the improvement of prenatal open and fetoscopic techniques, the outcome of SB-associated conditions could be improved and the risks to both the mother and the fetus reduced. A continuous follow-up of the treated infants and further randomized trials are essential to study the complications and advantages or disadvantages of any given treatment strategy.