Fetal Closure Research Articles

Periventricular nodular heterotopia in patients with a prenatal diagnosis of myelomeningocele/myeloschisis: associations with seizures and neurodevelopmental outcomes during early childhood.

Historically, the presence of gray matter heterotopia was a concern for adverse postnatal neurocognitive status in patients undergoing fetal closure of open spinal dysraphism. The purpose of this study was to evaluate neurodevelopmental outcomes and the onset of seizures during early childhood in patients with a prenatal diagnosis of myelomeningocele/myeloschisis (MMC) and periventricular nodular heterotopia (PVNH). All patients evaluated at the Center for Fetal Diagnosis and Treatment with a diagnosis of MMC between June 2016 to March 2023 were identified. PVNH was determined from prenatal and/or postnatal MRI. The Bayley Scales of Infant and Toddler Development (edition III or IV) were used for neurodevelopmental assessments. Patients were screened for seizures/epilepsy. Of 497 patients evaluated with a prenatal diagnosis of MMC, 99 were found to have PVNH on prenatal MRI, of which 35 had confirmed PVNH on postnatal imaging. From the 497 patients, 398 initially did not exhibit heterotopia on prenatal MRI, but 47 of these then had confirmed postnatal PVNH. The presence of PVNH was not a significant risk factor for postnatal seizures in early childhood. The average neurodevelopmental scores were not significantly different among heterotopia groups for cognitive, language, and motor domains. The presence of PVNH in patients with a prenatal diagnosis of MMC does not indicate an increased risk for neurodevelopmental delay at 1year of age. We did not demonstrate an association with seizures/epilepsy. These findings can aid clinicians in prenatal consultation regarding fetal repair of open spinal dysraphism. Long-term follow-up is required to discern the true association between PVNH seen on prenatal imaging and postnatal seizures/epilepsy and neurodevelopmental outcomes.

130 Heterotopia and Neurodevelopmental Outcomes Patients With Prenatal Diagnosis of Myelomeningocele or Myeloschisis

INTRODUCTION: Gray matter heterotopia is a cortical malformation and a known risk factor for seizures and epilepsy. Historically, presence of heterotopia in one or both cerebral ventricles was a concern for postnatal neurological status in patients undergoing fetal closure of myelomeningocele/myeloschisis. There is little information known regarding the overall impact of heterotopia in this patient population. METHODS: A retrospective chart review was conducted for all patients evaluated at the Center of Fetal Diagnosis and Treatment with a diagnosis of myelomeningocele or myeloschisis between June 2016 to March 2023. Gray matter heterotopia was determined from prenatal US and confirmed with prenatal and postnatal MRI. The Bayley Scales of Infant and Toddler Development (edition III and IV) were used for neurodevelopmental assessments. RESULTS: Of 497 patients evaluated with a prenatal diagnosis of myelomeningocele or myeloschisis, 99 were found to have gray matter heterotopia on prenatal MRI. In the postnatal period, 347 patients ultimately delivered at our institution, of which 26 had confirmed gray matter heterotopia on postnatal MRI as well as underwent neurodevelopmental testing. The median age at neurodevelopmental assessment was 13.3 months. The median cognitive and language scores (95 and 99, respectively) were average in those patients with gray matter heterotopia. CONCLUSIONS: This study suggests that the presence of gray matter heterotopia in patients with prenatal diagnosis of myelomeningocele or myeloschisis is not associated with increased cognitive or language delay on neurodevelopmental testing at approximately 1 year of age. These findings can aid clinicians during prenatal consultation regarding fetal repair of spina bifida.

Potential higher risk of tethered spinal cord in children after prenatal surgery for myelomeningocele: A systematic review and meta-analysis.

We performed a systematic review and meta-analysis on the incidence of secondary tethered spinal cord (TSC) between prenatal and postnatal closure in patients with MMC. The objectives was to understand the incidence of secondary TSC after prenatal surgery for MMC compared to postnatal surgery for MMC. On May 4, 2023, a systematic search was conducted in Medline, Embase, and the Cochrane Library to gather relevant data. Primary studies focusing on repair type, lesion level, and TSC were included, while non-English or non-Dutch reports, case reports, conference abstracts, editorials, letters, comments, and animal studies were excluded. Two reviewers assessed the included studies for bias risk, following PRISMA guidelines. TSC frequency in MMC closure types was determined, and the relationship between TSC occurrence and closure technique was analyzed using relative risk and Fisher's exact test. Subgroup analysis revealed relative risk differences based on study designs and follow-up periods. A total of ten studies, involving 2,724 patients, were assessed. Among them, 2,293 patients underwent postnatal closure, while 431 received prenatal closure for the MMC defect. In the prenatal closure group, TSC occurred in 21.6% (n = 93), compared to 18.8% (n = 432) in the postnatal closure group. The relative risk (RR) of TSC in patients with prenatal MMC closure versus postnatal MMC closure was 1.145 (95%CI 0.939 to 1.398). Fisher's exact test indicated a statistically non-significant association (p = 0.106) between TSC and closure technique. When considering only RCT and controlled cohort studies, the overall RR for TSC was 1.308 (95%CI 1.007 to 1.698) with a non-significant association (p = .053). For studies focusing on children up until early puberty (maximum 12 years follow-up), the RR for tethering was 1.104 (95%CI 0.876 to 1.391), with a non-significant association (p = 0.409). This review found no significant increase in relative risk of TSC between prenatal and postnatal closure in MMC patients, but a trend of increased TSC in the prenatal group. More long-term data on TSC after fetal closure is needed for better counseling and outcomes in MMC.

Global Policy and Practice for Intrauterine Fetal Resuscitation During Fetal Surgery for Open Spina Bifida Repair

Globally accepted recommendations suggest that a woman should be between 19 weeks and 25 weeks plus 6 days of pregnancy to be considered eligible for fetal closure of open spina bifida. A fetus requiring emergency delivery during surgery is therefore potentially considered viable and thus eligible for resuscitation. There is little evidence, however, to support how this scenario is addressed in clinical practice. To explore current policy and practice for fetal resuscitation during fetal surgery for open spina bifida in centers undertaking fetal surgery. An online survey was designed to identify current policies and practices in place to support fetal surgery for open spina bifida, exploring experiences and management of emergency fetal delivery and fetal death during surgery. The survey was emailed to 47 fetal surgery centers in 11 countries where fetal spina bifida repair is currently performed. These centers were identified through the literature, the International Society for Prenatal Diagnosis center repository, and an internet search. Centers were contacted between January 15 and May 31, 2021. Individuals volunteered participation through choosing to complete the survey. The survey comprised 33 questions of mixed multiple choice, option selection, and open-ended formats. Questions explored policy and practice supporting fetal and neonatal resuscitation during fetal surgery for open spina bifida. Responses were obtained from 28 of 47 centers (60%) in 11 countries. Twenty cases of fetal resuscitation during fetal surgery during the last 5 years were reported across 10 centers. Four cases of emergency delivery during fetal surgery after maternal and/or fetal complications during the last 5 years were reported across 3 centers. Fewer than half the 28 centers (n = 12 [43%]) had policies in place to support practice in the event of either imminent fetal death (during or after fetal surgery) or the need for emergency fetal delivery during fetal surgery. Twenty of 24 centers (83%) reported preoperative parental counseling on the potential need for fetal resuscitation prior to fetal surgery. The gestational age at which centers would attempt neonatal resuscitation after emergency delivery varied from 22 weeks and 0 days to more than 28 weeks. In this global survey study of 28 fetal surgical centers, there was no standard practice about how fetal resuscitation or subsequent neonatal resuscitation was managed during open spina bifida repair. Further collaboration between professionals and parents is required to ensure sharing of information to support knowledge development in this area.

Neurologic Outcome Comparison between Fetal Open-, Endoscopic- and Neonatal-Intervention Techniques in Spina Bifida Aperta.

In spina bifida aperta (SBA), fetal closure of the myelomeningocele (MMC) can have a neuroprotective effect and improve outcomes. In Europe, surgical MMC closure is offered by fetal-open (OSBAR), fetal-endoscopic (FSBAR), and neonatal (NSBAR) surgical techniques. Pediatric neurologists facing the challenging task of counseling the parents may therefore seek objective outcome comparisons. Until now, such data are hardly available. In SBA, we aimed to compare neurologic outcomes between OSBAR, FSBAR, and NSBAR intervention techniques. We determined intervention-related complications, neuromuscular integrity, and neurologic outcome parameters after OSBAR (n = 17) and FSBAR (n = 13) interventions by age- and lesion-matched comparisons with NSBAR-controls. Neurological outcome parameters concerned: shunt dependency, segmental alterations in muscle ultrasound density (reflecting neuromuscular integrity), segmental motor-, sensory- and reflex conditions, and the likelihood of intervention-related gain in ambulation. Compared with NSBAR-controls, fetal intervention is associated with improved neuromuscular tissue integrity, segmental neurological outcomes, reduced shunt dependency, and a higher chance of acquiring ambulation in ≈20% of the operated children. Children with MMC-lesions with a cranial border at L3 revealed the most likely intervention-related motor function gain. The outcome comparison between OSBAR versus FSBAR interventions revealed no significant differences. In SBA, OSBAR- and FSBAR-techniques achieved similar neuroprotective results. A randomized controlled trial is helpful in revealing and compare ongoing effects by surgical learning curves.

Premature fetal closure of the ductus arteriosus of unknown cause – could it be influenced by maternal consumption of large quantities of herbal chamomile tea – a case report?

Abstract Objectives The aim of this article was to present a case of premature fetal closure of the ductus arteriosus (DA) of unknown cause. Case presentation A 32-year-old pregnant woman came for the regular prenatal visit at 36 + 1 weeks of gestation (WG) at which oligohydramnios and premature closure of DA were revealed. Use of non-steroidal anti-inflammatory drugs was excluded by the history, although the patient had the symptoms of common cold 2 weeks before the check-up taking more than 1,000 mL of strong chamomile tea daily till the day before the prenatal visit. The patient was hospitalized at 36 + 1 weeks of gestation due to premature closure of DA and oligohydramnios (amniotic fluid index = 4.5/3), which was the indication to deliver the baby by cesarean section at 36 + 6 WG (birth weight was 2,830 g, birth length 49 cm and head circumference 34 cm, Apgar score at 1 and 5 min were 9/9). Postnatal course was uneventful, and postnatal echocardiography at 12 h of life revealed functionally closed DA and mild dysfunction of the right ventricle, which completely resolved after 7 days. The mother and the baby were discharged home healthy, and were doing well 3 months after delivery. Conclusions Although the cause of premature closure of DA in most of the cases will remain undetected, thorough history sometimes with unexpected events should be taken under the consideration as possible causative factor for premature DA closure, as was drinking of high quantities of chamomile tea in our case.

Post-natal diagnosis and catheter-based management of premature fetal ductal closure presenting as unilateral pulmonary artery thrombosis and right ventricular failure.

Post-natal diagnosis and catheter-based management of premature fetal ductal closure presenting as unilateral pulmonary artery thrombosis and right ventricular failure.

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

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. 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. 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. 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.

Optical coherence tomography angiography of a bilateral optic disc pit

Optic disc pit (ODP) is a rare congenital defect presumably arising from the failure of fetal fissure closure in embryogenesis. It occurs in about 1 in 10,000 people with no gender predilection. ODP is usually unilateral. We describe the case of a 52-year-old female patient who presented for a regular ophthalmic examination. Visual acuity was 20/20 and anterior segment was unremarkable in both eyes. Fundus revealed a bilateral optic pit located inferotemporally within the nerve (A,B). Swept-Source Optical Coherence Tomography demonstrated the defect caused by the ODP without secondary retinoschisis or subretinal fluid in both eyes (C,D). Optical Coherence Tomography Angiography (OCT-A) showed the ODP as a hyporeflective lesion in the optic nerve head, irregular-shaped in the right eye and round-shaped in the left eye (E,F). OCT-A has also displayed a decrease in vascular density with no-flow within the defect (G,H). A 6-month clinical monitoring has been undertaken.

Intrauterine closure of myelomeningocele is associated with superior long-term quality of life than postnatal closure: a single-center study.

The Management of Myelomeningocele Study (MOMS) established several important benefits of myelomeningocele fetal closure, including decreased need for shunting at 30 months. However, the effects of fetal closure on long-term quality of life (QOL) have not been studied. In this study, the authors aimed to analyze the differences in long-term QOL between children treated with intrauterine repair and those treated with postnatal repair. Caregivers of children treated with either intrauterine or postnatal closure at a tertiary acute care hospital between 1997 and 2003 were contacted to participate. The Pediatric Quality of Life Inventory (PedsQL 4.0) and a surgical history questionnaire were administered over the phone. Responses to the QOL survey were reverse scored and linearly transformed to a 0-100 scale, with a higher score indicating better QOL. The Mann-Whitney U-test was used to analyze differences in means. Seventy-four children had MMC repair between 1997 and 2003. Twenty-three (31%) of the patients' families responded to the PedsQL 4.0 questionnaire. Of these 23 children, 11 had intrauterine closure and 12 had postnatal closure. The intrauterine group did not differ in age (median [IQR] 17 years [14-17 years] vs 15 years [14-19 years], p = 0.926), sex (27.3% vs 41.7% male, p = 0.469), or lesion level (p = 0.199) from the postnatal group. Fewer patients in the intrauterine group underwent neurosurgical procedures than those in the postnatal group (55.6% vs 100%, p = 0.018). However, of the children receiving neurosurgical procedures, there was no difference in the number of procedures between the intrauterine and postnatal groups (median [IQR] 4 [2-10.5] vs 2.5 [1.75-6.25], p = 0.458). There was no difference in the percentage of children receiving nonneurosurgical procedures between the two groups (100% vs 100%, p > 0.99). Children who underwent intrauterine closure had significantly higher psychosocial health (median [IQR] 70.0 [56.7-83.3] vs 55.0 [42.1-60.0], p = 0.015) as well as total QOL (median [IQR] 56.5 [55.4-81.5] vs 49.5 [32.9-59.0], p = 0.019) than children with postnatal closure. Physical health was not significantly different between the two groups (median [IQR] 62.5 [37.5-78.1] vs 39.1 [18.8-59.4], p = 0.108). Relative to postnatal closure, children who underwent intrauterine closure of MMC demonstrated better long-term QOL as measured by psychosocial and overall QOL metrics. Given that not all medical and socioeconomic confounders were adjusted for due to the low sample size, validation of these results in a larger population and across multiple centers is needed.

MOMS Plus: Single-Institution Review of Outcomes for Extended BMI Criteria for Open Fetal Repair of Myelomeningocele

Background: In utero repair has become an accepted therapy to decrease the rate of ventriculoperitoneal shunting and improve neurologic function in select cases of myelomeningocele. The Management of Myelomeningocele Study (MOMS) trial excluded patients with a BMI >35 due to concerns for increased maternal complications and preterm delivery, limiting the population that may benefit from this intervention. Objectives: The aim of this study was to evaluate outcomes associated with extending the maternal BMI criteria to 40 in open fetal repair of myelomeningocele. Method: Retrospective review of fetal closure of myelomeningocele at a quaternary referral center between 2013 and 2016 with maternal BMI ranging from 35 to 40. Results: Eleven patients with a BMI >35 were identified. The average BMI was 37. The average maternal age at the time of evaluation was 27 years. The average gestational age at fetal surgery was 24 weeks. Gestational age at birth was an average of 32 weeks. There was one perinatal death immediately following the fetal intervention. The shunt rate at 1 year was 45% (5/11 patients). Conclusions: In this single-institution review of expanded BMI criteria for fetal repair of myelomeningocele, we did not observe any adverse maternal outcomes associated with maternal obesity; however, the gestational age at delivery was 2 weeks earlier compared to the MOMS trial.

Two-Port Endoscopic Fetal Closure of Myelomeningocele

Introduction: Open neural tube defects are a common congenital abnormality with significant consequences for affected children and their families. Issues include paraplegia, walking difficulties, bowel and bladder incontinence, and hydrocephalus. The 2011 Management of Myelomeningocele Study established fetal closure as a treatment option.1 Fetal closure reduces the incidence of hydrocephalus and improves motor outcomes compared with conventional postnatal closure. Open prenatal closure, however, necessitates hysterotomy and significantly increases the risk of preterm delivery and uterine dehiscence.2 Endoscopic approaches eliminating the need for hysterotomy have been described.3–5 Here we demonstrate our two-port endoscopic technique. Materials and Methods: The mother is at 26 weeks gestation and ultrasonography work-up has revealed a myelomeningocele defect of the fetus at the L3-S1 levels. A transverse abdominal opening is made for uterine exposure. Two ports are placed 6 cm apart with ultrasound guidance into the fundus of the uterus. A total of 300 cc of amniotic fluid are removed and the uterus is insufflated with humidified CO2 gas. The fetus and myelomeningocele defect are observed under endoscopic guidance. Endoscopic closure of the myelomeningocele is done in two major steps. First, the neural placode is released through sharp circumferential dissection of the arachnoid lying between the neural placode margin and the junctional zone. Second, the defect is closed primarily with interrupted vertical mattress sutures. Closure is facilitated with the use of relaxing flank incisions and retention sutures. Results: The child was born term at 39 weeks through vaginal delivery. Her neurologic examination demonstrates intact spinal function inclusive of the S1 level. Conclusions: Endoscopic fetal closure of myelomeningocele is technically feasible and can be accomplished through a two-port technique utilizing single layer closure. The avoidance of hysterotomy with this method may reduce the risk of preterm delivery and uterine dehiscence. No competing financial interests exist. Runtime of video: 6 mins 19 secs Related Presentations: Podium Presentation (ID 83697), IPEG's 26th Annual Congress for Endosurgery in Children, July 20, 2017, London, England.

Postnatal Hypertrophy and Dysfunction of the Right Ventricle with Cyanosis as Sequelae of Missed Diagnosis of Prenatal Duct Closure: Presentation of 5 Cases and Review of the Literature

Introduction: The prevalence of prenatal duct-closure is unknown and probably underestimated. Depending on the time of fetal closure this condition causes a wide range of postnatal clinical pathology from mild cyanosis and diastolic dysfunction of the right heart to respiratory insufficiency in severe right heart disease. Differential diagnoses for the postnatal findings include cyanotic congenital cardiac defects, persistent pulmonary hypertension, right ventricular cardiomyopathy and normally easier to distinguish Chiari network or Eustachian valve. Without prenatal suspicion establishing the postnatal diagnosis of premature duct closure is often difficult and considered only retrospectively from the clinical course.

PP02.5 – 2943: Neurological outcome in MMC patients after fetal surgery – Results from the Zurich cohort

Objective The purpose of this study was to investigate the neurological outcome of patients with meningomyelocele treated with fetal closure in Zurich. Methods 14 patients were included, of two data were collected retrospectively, 12 were followed prospectively by a detailed evaluation protocol. We investigated the anatomical spinal level in utero before surgery by in utero MR imaging. The functional spinal level at birth, 3 months, 6 months and 12 months of age was compared to the anatomical level in utero. Chiari II-malformation and remission of hindbrain herniation over the course was investigated by MRI. Data of head circumference, shunt placement, bladder dysfunction and development were collected. Our results were compared to the results of the MOMS study (A randomized trial of prenatal versus postnatal repair of myelomeningocele. Adzick et al. NEJM, 2011 Mar 17;364(11):993–1004). Results Anatomical level in utero ranged between L1 to L5. According to the anatomical level the functional level after surgery was two or more levels better in 28%, level of function one level better in 21%, no difference was seen in 43%, level of function two level worse in 7%. Interestingly 75% of our patients had partial motor innervation below the functional level. Before surgery Chiari II-malformation was detected in all 14 patients, after fetal surgery we had no evidence of hindbrain herniation in any. In 46.1% shunt placement was necessary. 66% had neurogenic bladder dysfunction. Conclusion Our results from this small cohort show nearly the same results as reported in the MOMS trial, especially regarding shunt placement. A part of our patients showed a relevant partial motor innervation below the level, it is to discuss if this could be a result of fetal intervention, just as the low frequency of shunt placement and complete demission of hindbrain herniation.

Fetal Myelomeningocele Closure: Technical Considerations

Myelomeningocele (MMC) is one of the most common serious congenital malformations. Typically this condition has been treated with closure of the MMC defect shortly after birth. In general, surgery for MMC aims to provide a multilayered closure to provide protection to the neural elements, prevent leakage of spinal fluid and reduce infection risks. A randomized controlled trial, the Management of Myelomeningocele Study (MOMS), has shown that closure during the fetal period can be performed relatively safely and can result in significant benefit to the child. Whereas the surgical technique of prenatal closure of an MMC defect is similar to a postnatal closure, there are some important technical differences. The goal of this paper is to describe the technique of fetal closure of MMC defects, highlight the unique steps that are needed for this surgery and delineate some potential pitfalls.

Fetal surgery for myelomeningocele: progress and perspectives

Myelomeningocele (MMC), one of the most common congenital malformations, can result in severe lifelong disabilities, including paraplegia, hydrocephalus, Chiari II malformation, bowel and bladder dysfunction, skeletal deformations, and neurocognitive impairment. Experimental studies provide compelling evidence that the neurological deficits associated with MMC are not simply caused by incomplete neurulation but rather by the prolonged exposure of the vulnerable neural elements to the intrauterine environment. MMC is the first non-lethal anomaly considered for fetal surgical intervention, necessitating a careful analysis of risks and benefits. Retrospective and prospective randomized studies suggest that fetal surgery of MMC before 26 weeks of gestation may preserve neuromotor function, reverse hindbrain herniation, and reduce the need for ventriculoperitoneal shunting. However, these studies also demonstrate that fetal surgery is associated with significant maternal and fetal risks. Consequently, additional research is necessary to further elucidate the pathophysiology of MMC, to define the ideal timing and technique of fetal closure, and to evaluate the long-term implications of prenatal intervention.

P021 Fetal closure of the MMC followed by caesarean section may have a beneficial effect upon neuromuscular condition in spina bifida

P021 Fetal closure of the MMC followed by caesarean section may have a beneficial effect upon neuromuscular condition in spina bifida

OP04.02: Premature fetal closure of the arterial duct: clinical presentation and outcome

OP04.02: Premature fetal closure of the arterial duct: clinical presentation and outcome

Bladder and External Urethral Sphincter Function After Prenatal Closure of Myelomeningocele

We compared urodynamic findings in patients who underwent prenatal closure of myelomeningocele with those of patients who underwent postnatal closure, and equivalent lower urinary tract evaluations. Urodynamic studies of 5 patients (2 boys, 3 girls) who underwent prenatal closure of myelomeningocele were compared to those of 88 patients with similar level lesions who underwent repair postnatally between 1979 and 2002. All 5 patients in the prenatally treated cohort had lower lumbosacral lesions on neurological examination. These patients displayed no evidence of electromyographic activity, indicating complete denervation of the external sphincter. In comparison 34 of the 88 patients in the postnatal cohort (39%) lacked sphincter activity at newborn examination, with similar findings noted at 1-year evaluation. In terms of bladder function all 5 patients in the prenatal cohort exhibited detrusor overactivity, compared to 33 of the 88 patients (38%) in the postnatal cohort at the newborn examination, with similar findings at 1-year evaluation. Fetal closure of myelomeningocele is associated with a higher incidence of complete denervation of the external urethral sphincter and detrusor overactivity compared to postnatal closure. Patients who undergo this novel procedure should undergo urodynamic studies in the immediate newborn period and should be under close postnatal surveillance to document possible tethering of the spinal cord, urinary incontinence and increased detrusor pressures.

Anaesthesia for fetal surgery.

*Department of Anesthesia, Children’s Hospital, Harvard Medical School, Boston, MA,**Department of Anesthesiology and Critical Care, The Children’s Hospital of Philadelphia,University of Pennsylvania School of Medicine, Philadelphia and †Department of Anesthesia andCritical Care, The Hospital of the University of Pennsylvania, University of Pennsylvania Schoolof Medicine, Philadelphia, PA, USA