Fetal surgery for neural tube defects

Imaging Fetal Spine Malformations in the Context of In Utero Surgery

This review covers the embryology, definition, and diagnosis of open spinal dysraphism with a focus on fetal ultrasound and MR imaging findings. Differentiating open versus closed spinal dysraphic defects on fetal imaging will also be discussed. Current fetal surgery practices and imaging findings in the context of fetal surgery are also reviewed.

Bilateral Knee Arthrodesis and Total Hip Arthroplasty for Knee and Hip Dysplasia Secondary to Spina Bifida: A Case Report

Introduction

Spina bifida is a rare neurological condition that, if uncorrected, may cause chronic valgus knee stress difficulty with independent ambulation and significant pain. Current literature lacks comprehensive guidance on surgically correcting progressive hip and knee deformities in spina bifida patients, which include osteotomy and primary. When these options are contraindicated, alternative approaches such as arthrodesis may be indicated, although they remain understudied in this population.

Case Report

A 47-year-old man presented with bilateral hip and knee pain. Radiographs demonstrated valgus knee deformities with severe arthrosis and bilateral femoral head subluxation. The patient had a history of spina bifida with chronic lower extremity weakness and neurogenic bladder. He underwent staged bilateral instrumented knee arthrodesis and staged bilateral total hip arthroplasty (THA).

Conclusion

This is the first reported case of bilateral instrumented knee arthrodesis in a patient with spina bifida. Orthopedic care of these patients is complex. Surgical correction of symptomatic knee and hip deformities through instrumented arthrodesis and THA may permit an improved functional outcome.

Myelomeningocele: Long-Term Neurosurgical Management

Open spina bifida, also known as myelomeningocele (MMC), is the most challenging and severe birth defect of the central nervous system compatible with life and it is due to a failure in the dorsal fusion of the nascent neural tube during embryonic development. MMC is often accompanied by a constellation of collateral conditions, including hydrocephalus, Arnold - Chiari II malformation, brainstem disfunction, hydrosyringomyelia, tethered cord syndrome and scoliosis. Beyond early surgical repair of the dorsal defect, MMC requires lifelong cares. Several additional surgical procedures are generally necessary to improve the long-term outcomes of patients affected by MMC and multidisciplinary evaluations are crucial for early identification and management of the various medical condition that can accompany this pathology. In this chapter, the most common pathological entities associated with MMC are illustrated, focusing on clinical manifestations, treatment strategies and follow up recommendations.

Long-term neurological cognitive, behavioral, functional, and quality of life outcomes after fetal myelomeningocele closure: a systematic review

BACKGROUND

Myelomeningocele is a lifelong condition that features several comorbidities, such as hydrocephalus, scoliosis, club foot, and lower limb sensory and motor disabilities. Its management has progressed over time, ranging from supportive care to early postnatal closure to prenatal closure of the defect. Recent research discovered that fetal myelomeningocele closure (fMMC) provided superior neurological outcomes to those of postnatal closure. When performed at 12 months of age, fMMC can avert or delay the need for a ventriculoperitoneal shunt and reversed the hindbrain herniation. Moreover, fMMC reportedly enhanced motor function and mental development at 30 months of age. However, its long-term outcomes remain dubious.

PURPOSE

This systematic review aimed to determine the long-term neurological cognitive, behavioral, functional, and quality of life (QoL) outcomes after fMMC.

METHODS

The PubMed, Directory of Open Access Journals, EBSCO, and Cochrane databases were extensively searched for articles published in 2007-2022. Meta-analyses, clinical trials, and randomized controlled trials with at least 5 years of follow-up were given priority.

RESULTS

A total of 11 studies were included. Most studies revealed enhanced long-term cognitive, behavioral, functional, and QoL outcomes after fMMC.

CONCLUSION

Our results suggest that fMMC substantially enhanced patients' long-term neurological cognitive, behavioral, functional, and QoL outcomes.

Prenatal and Postnatal Therapies for Down's Syndrome and Associated Developmental Anomalies and Degenerative Deficits: A Systematic Review of Guidelines and Trials

Down's syndrome (DS) is the most common genetic disorder at birth. Multiple developmental abnormalities before birth and early onset of degenerative deficits after birth are features of DS. Early treatment for the manifestations associated with DS in either prenatal or postnatal period may improve clinical outcomes. However, information available from professional bodies and to communities is very limited. We carried out a systematic review and attempted meta-analysis of clinical trials for developmental abnormalities and degenerative deficits in DS. Only 15 randomized controlled trials (RCTs) in 995 (24 days to 65 years old) individuals with DS showed some improvement in cognitive disorders, development and growth, and musculoskeletal problem. However, each trial used different parameters and methods to measure various outcomes. RCTs of prenatal interventions in fetus with DS are lacking. The efficacy and safety of specific interventions in DS are still largely unknown. Proper counseling of the potential treatment for pregnant mothers who wish to continue their pregnancy carrying fetus with DS, and to health care professionals who take care of them are not adequate nowadays.

Clinical and Radiological Predictors of Ventriculoperitoneal Shunt Insertion in Myelomeningocele Patients

BACKGROUND: Myelomeningocele (MMC) is one of the most common developmental anomalies of the CNS. Many of these patients develop hydrocephalus (HCP). The rate of cerebrospinal fluid diversion in these patients varies significantly in literature, from 52% to 92%. MMC repair conventionally occurs in the post-natal period. With the technological advances in surgical practice and fetal surgeries, intra uterine MMC repair IUMR is adopted in some centers. Cerebrospinal fluid shunting has numerous complications, most notably shunt failure and shunt infection. Studies have suggested that patients with greater numbers of shunt revisions have poorer performance on neuropsychological testing. There is also good evidence to suggest that the IQs of patients with MMC who do not undergo shunt placement are higher than that of their shunt treated counterparts. AIM: In this study, we are trying to identify strong clinical and radiological predictors for the need of ventriculoperitoneal (VP) shunt insertion in patients with MMC who underwent surgical repair and closure of the defect initially. This will decrease the overall rate of shunt placement in this group of patients through applying a strict policy adopting only shunt insertion for the desperately needing patient. METHODS: Prospective clinical study conducted on 96 patients with MMC presented to Aboul Reish Pediatric Specialized Hospital, Cairo University. After confirming the diagnosis through clinical and radiological aids, patients are carefully examined, if HCP is evident clinically and radiologically a shunt is inserted together with MMC repair at the same session after excluding sepsis or cerebrospinal fluid (CSF) infection, (GROUP A). If there are no signs of increased ICP, MMC repair shall be done alone (GROUP B). Those patients shall be monitored carefully postoperatively and after discharge and shall be followed up regularly to early detect and promptly manage latent HCP. Multiple clinical and radiological indices were used throughout the follow-up period and statistical significance of each was measured. RESULTS: Shunt placement was required in 45 (46.88%) of the 96 patients. Eighteen patients (18.75%) needed the shunt as soon as they presented to us (GROUP A), because they were having clinically active HCP. Twenty-seven (28.13%) patients were operated on by MMC repair initially without shunt placement because they did not have signs of increased ICP at the time of presentation. Yet, they developed latent HCP requiring shunt placement during the follow-up period (GROUP B2). Fifty-one patients of the study population (53.13%) underwent surgical repair of the MMC without the need of further VP insertion and they were followed up for 6 months period after the repair without developing latent HCP (GROUP B1). Patients of GROUP B were the study population susceptible for the development of latent HCP. Out of 78 patients in GROUP B, only 27 patients (34.62%) needed a VP shunt. CONCLUSION: In our study, we found that the rate of shunt insertion in patients with MMC is lower than the previously reported rate in the literature. A more thorough evaluation of the patient’s post-operative need for a shunt is mandatory. We suggest that we could accept postoperative (after MMC repair) ventriculomegaly provided it does not mean any deterioration in the patient’s clinical or developmental state. We assume that reduction of shunt insertion rate will eventually reduce what has previously been an enormous burden for a significant proportion of children with MMC.

Analgesia for fetal pain during prenatal surgery: 10 years of progress

Some doubts on the necessity and safety of providing analgesia to the fetus during prenatal surgery were raised 10 years ago. They were related to four matters: fetal sleep due to neuroinhibitors in fetal blood, the immaturity of the cerebral cortex, safety, and the need for fetal direct analgesia. These objections now seem obsolete. This review shows that neuroinhibitors give fetuses at most some transient sedation, but not a complete analgesia, that the cerebral cortex is not indispensable to feel pain, when subcortical structures for pain perception are present, and that maternal anesthesia seems not sufficient to anesthetize the fetus. Current drugs used for maternal analgesia pass through the placenta only partially so that they cannot guarantee a sufficient analgesia to the fetus. Extraction indices, that is, how much each analgesic drug crosses the placenta, are provided here. We here report safety guidelines for fetal direct analgesia. In conclusion, the human fetus can feel pain when it undergoes surgical interventions and direct analgesia must be provided to it. IMPACT: Fetal pain is evident in the second half of pregnancy. Progress in the physiology of fetal pain, which is reviewed in this report, supports the notion that the fetus reacts to painful interventions during fetal surgery. Evidence here reported shows that it is an error to believe that the fetus is in a continuous and unchanging state of sedation and analgesia. Data are given that disclose that drugs used for maternal analgesia cross the placenta only partially, so that they cannot guarantee a sufficient analgesia to the fetus. Safety guidelines are given for fetal direct analgesia.

Imaging of open spinal dysraphisms in the era of prenatal surgery

Over the last decade fetal surgery to repair open spinal dysraphisms has become an acceptable and in some cases desirable alternative to the traditional method of postnatal closure. Fetal MRI is an essential part of the workup in these patients, not only to select the appropriate candidates for fetal surgery but also to guide prenatal counseling and perinatal management. In this article we review current surgical techniques for prenatal repair, relevant imaging findings in the era of fetal surgery, and expected imaging findings of the brain and spine in the fetal and postnatal periods.

Minimally invasive fetal surgery for myelomeningocele: preliminary report from a single center

OBJECTIVE

Recent trials have shown the safety and benefits of fetoscopic treatment of myelomeningocele (MMC). The authors' aim was to report their preliminary results of prenatal fetoscopic treatment of MMC using a biocellulose patch, focusing on neurological outcomes, fetal and maternal complications, neonatal CSF leakage, postnatal hydrocephalus, and radiological outcomes.

METHODS

Preoperative assessment included clinical examination, ultrasound imaging, and MRI of the fetus. Patients underwent purely fetoscopic in utero MMC repair, followed by postoperative in utero and postnatal MRI. All participants received multidisciplinary follow-up.

RESULTS

Five pregnant women carrying fetuses affected by MMC signed informed consent for the fetoscopic treatment of the defect. The mean MMC size was 30.4 mm (range 19-49 mm). Defect locations were L1 (2 cases), L5 (2 cases), and L4 (1 case). Hindbrain herniation and ventriculomegaly were documented in all cases. The mean gestational age at surgery was 28.2 weeks (range 27.8-28.8 weeks). Fetoscopic repair was performed in all cases. The mean gestational age at delivery was 33.9 weeks (range 29.3-37.4 weeks). After surgery, reversal of hindbrain herniation was documented in all cases. Three newborns developed signs of hydrocephalus requiring CSF diversion. Neurological outcomes in terms of motor level were favorable in all cases, but a premature newborn died due to CSF infection and sepsis.

CONCLUSIONS

The authors' preliminary results suggest that fetoscopic treatment of MMC is feasible, reproducible, and safe for mothers and their babies. Neurological outcomes were favorable and similar to those in the available literature. As known, prematurity was the greatest complication.

Just choice: a Danielsian analysis of the aims and scope of prenatal screening for fetal abnormalities

Developments in Non-Invasive Prenatal Testing (NIPT) and cell-free fetal DNA analysis raise the possibility that antenatal services may soon be able to support couples in non-invasively testing for, and diagnosing, an unprecedented range of genetic disorders and traits coded within their unborn child's genome. Inevitably, this has prompted debate within the bioethics literature about what screening options should be offered to couples for the purpose of reproductive choice. In relation to this problem, the European Society of Human Genetics (ESHG) and American Society of Human Genetics (ASHG) tentatively recommend that any expansion of this type of screening, as facilitated by NIPT, should be limited to serious congenital and childhood disorders. In support of this recommendation, the ESHG and ASHG cite considerations of distribution justice. Notably, however, an account of justice in the organization and provision of this type of screening which might substantiate this recommendation has yet to be developed. This paper attempts to redress this oversight through an investigation of Norman Daniels' theory of Just health: meeting health needs fairly. In line with this aim, the paper examines what special moral importance (for Just health) screening for the purpose of reproductive choice might have where concerning serious congenital and childhood disorders in particular. The paper concludes that screening for reproductive choice where concerning serious congenital and childhood disorders may be important for providing women with fair opportunity to protect their health (by either having or not having an affected child).

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

PURPOSE

The purpose of the study is to examine MRI findings of the brain and spine on prenatal and postnatal MRI following intrauterine repair of open spinal dysraphism (OSD) by open hysterotomy and fetoscopic approaches.

MATERIALS AND METHODS

This study is a single-center HIPAA-compliant and IRB-approved retrospective analysis of fetal MRIs with open spinal dysraphism from January 2011 through December 2018 that underwent subsequent prenatal repair of OSD.

RESULTS

Sixty-two patients met inclusion criteria: 47 underwent open repair, and 15 underwent fetoscopic repair, with an average gestational age of 22.6 ± 1.4 weeks at initial MRI. On postnatal MRI, spinal cord syrinx was seen in 34% (16/47) of patients undergoing open versus 33.3% (5/15) undergoing fetoscopic repair (P = 0.96). Postnatally, there was no significant difference in hindbrain herniation between the open versus fetoscopic repair groups (P = 0.28). Lateral ventricular size was significantly larger in the open (20.9 ± 6.7 mm) versus the fetoscopic repair (16.1 ± 4.9 mm) group (P = 0.01).

CONCLUSION

Though lateral ventricular size in the open repair group was larger than the fetoscopic repair group, this can likely be explained by initial selection criteria used for fetoscopic repair. Other postoperative imaging parameters on postnatal MRI were not significantly different between the two groups.

New insights into fetal pain

Fetal pain is difficult to assess, because the main feature needed to spot pain, is the subject's capability of declaring it. Nonetheless, much can be affirmed about this issue. In this review we first report the epochs of the development of human nociceptive pathways; then we review since when they are functioning. We also review the latest data about the new topic of analgesia and prenatal surgery and about the scarce effect on fetal pain sentience of the natural sedatives fetuses produce. It appears that pain is a neuroadaptive phenomenon that emerges in the middle of pregnancy, at about 20-22 weeks of gestation, and becomes more and more evident for bystanders and significant for the fetus, throughout the rest of the pregnancy.

Spinal Imaging Findings of Open Spinal Dysraphisms on Fetal and Postnatal MRI

BACKGROUND AND PURPOSE

Fetal MRI has become a valuable tool in the evaluation of open spinal dysraphisms making studies comparing prenatal and postnatal MRI findings increasingly important. Our aim was to determine the accuracy of predicting the level of the spinal dysraphic defect of open spinal dysraphisms on fetal MR imaging and to report additional findings observed when comparing fetal and postnatal MR imaging of the spine in this population.

MATERIALS AND METHODS

A single-center retrospective analysis was performed of fetal MRIs with open spinal dysraphisms from 2004 through 2016 with available diagnostic postnatal spine MR imaging. Images were reviewed by 2 board-certified fellowship-trained pediatric neuroradiologists. Corresponding clinical/operative reports were reviewed.

RESULTS

One hundred nineteen fetal MRIs of open spinal dysraphisms were included. The level of the osseous defect between fetal and postnatal MR imaging was concordant in 42.9% (51/119) of cases and was 1 level different in 39% (47/119) of cases. On postnatal MR imaging, type II split cord malformation was seen in 8.4% (10/119) of cases, with only 50% (5/10) of these cases identified prospectively on fetal MR imaging. Syrinx was noted in 3% (4/119) of prenatal studies, all cervical, all confirmed on postnatal MR imaging.

CONCLUSIONS

Fetal MR imaging is accurate in detecting the level of the spinal dysraphic defect, which has an impact on prenatal counseling, neurologic outcomes, and eligibility for fetal surgery. In addition, fetal MR imaging is limited in its ability to detect split cord malformations in patients with open spinal dysraphisms. Although rare, fetal MR imaging has a high specificity for detection of cervical spinal cord syrinx.

Comparing neurodevelopmental outcomes at 30 months by presence of hydrocephalus and shunt status among children enrolled in the MOMS trial

PURPOSE

To evaluate for differences in neurodevelopmental outcomes at 30 months of age for children enrolled in the Management of Myelomeningocele Study (MOMS) based on the presence of hydrocephalus and cerebral shunts.

METHODS

Children with no hydrocephalus (N= 27), children with shunted hydrocephalus (N= 108), and children with unshunted hydrocephalus (N= 36) were compared at 30 months of age on the Bayley II Mental and Psychomotor Indices, the Peabody Developmental Motor Scales-2 and the Preschool Language Scale, 4th edition. Generalized linear models were used to adjust for factors significantly different between the groups at baseline. Additional analyses were conducted to evaluate the impact of the severity of hydrocephalus.

RESULTS

In unadjusted comparisons, statistically significant differences were noted between the three groups on the Peabody Gross Motor Quotient and thus the Total Motor Quotient. After adjustment, no statistically significant differences were identified. In subanalyses, children with more severe hydrocephalus fared worse on the Peabody Fine Motor Quotient (median 88 versus 94, p= 0.005), the Total Motor Quotient (median 70 versus 73, p= 0.02) and both Preschool Language Scale subtests (auditory comprehension: median 93 versus 104, p= 0.02 and expressive communication: median 95 versus 104.5, p= 0.01) and thus the total score (median 92 versus 105, p= 0.004). These results remained significant in the multivariable adjusted model.

CONCLUSION

No neurodevelopmental differences were noted with children enrolled in MOMS across the three hydrocephalus/shunt groups, although severity of hydrocephalus was associated with poorer outcomes.

The Perfect Womb: Promoting Equality of (Fetal) Opportunity

This paper aims to address how artificial gestation might affect equality of opportunity for the unborn and any resultant generation of "ectogenetic" babies. It will first explore the current legal obstacles preventing the development of ectogenesis, before looking at the benefits of allowing this technology to control fetal growth and development. This will open up a discussion of the treatment/enhancement divide regarding the use of reproductive technologies, a topic featured in various bioethical debates on the subject. Using current maternity practices in Western society as a comparator, this paper will conclude that neither naturally nor artificially gestated fetuses have interests that can conflict with those of potential parents who might want to use this technology to control fetal development. Such control may include selective implantation of embryos of a desired gender, deliberate choice of genetic traits, or maintenance of an ideal incubation environment to avoid fetal damage. Objections on the basis of disability as well as concerns regarding eugenics will be addressed. The paper will conclude that none of these objections are compelling grounds to prevent the development and use of ectogenesis technologies for the purpose of achieving specific reproductive goals, particularly when compared to current practices in pre-implantation genetic diagnosis and selective abortion on the grounds of undesired traits. As such, when deciding whether to support ectogenesis research, the enduring interests of parents must be the primary consideration, with societal concerns regarding potential misuse the only valid secondary consideration.

Application potential of bone marrow mesenchymal stem cell (BMSCs) based tissue-engineering for spinal cord defect repair in rat fetuses with spina bifida aperta

Spina bifida aperta are complex congenital malformations resulting from failure of fusion in the spinal neural tube during embryogenesis. Despite surgical repair of the defect, most patients who survive with spina bifida aperta have a multiple system handicap due to neuron deficiency of the defective spinal cord. Tissue engineering has emerged as a novel treatment for replacement of lost tissue. This study evaluated the prenatal surgical approach of transplanting a chitosan-gelatin scaffold seeded with bone marrow mesenchymal stem cells (BMSCs) in the healing the defective spinal cord of rat fetuses with retinoic acid induced spina bifida aperta. Scaffold characterisation revealed the porous structure, organic and amorphous content. This biomaterial promoted the adhesion, spreading and in vitro viability of the BMSCs. After transplantation of the scaffold combined with BMSCs, the defective region of spinal cord in rat fetuses with spina bifida aperta at E20 decreased obviously under stereomicroscopy, and the skin defect almost closed in many fetuses. The transplanted BMSCs in chitosan-gelatin scaffold survived, grew and expressed markers of neural stem cells and neurons in the defective spinal cord. In addition, the biomaterial presented high biocompatibility and slow biodegradation in vivo. In conclusion, prenatal transplantation of the scaffold combined with BMSCs could treat spinal cord defect in fetuses with spina bifida aperta by the regeneration of neurons and repairmen of defective region.

Myelomeningocele (open spina bifida) - surgical management

Myelomeningocele has been recognized since ancient times although written descriptions began not before the 17th century. Among all serious congenital malformations, myelomeningocele is unique that is has a steady and considerable prevalence while being compatible with life. It has a dismal prognosis when left untreated where virtually all die within the first year while aggressive treatment have a profound effect on survival and quality of life. Effective surgical treatment became possible parallel to the treatment of hydrocephalus in the late 1950s. Advent of the shunt systems undoubtedly changed the morbidity and mortality rates due to associated hydrocephalus. Aggressive and effective treatment improved survival rates but also those suffering physical and mental disabilities have increased as well. Ethical and socioeconomic concerns have led to proposal for selective treatment criteria which have raised arguments on medical and ethico-legal rounds. After the swing of the pendulum between early treatment in all affected children and selective treatment of those who fulfilled the criteria for good prognosis, early myelomeningocele repair is practiced widely unless the infant is critically ill.Incidence of myelomeningocele has been decreasing especially in the Western world, partly due to prenatal diagnosis and elective terminations, dietary folate supplementation. Still, it is the most common central nervous system malformation and one of the leading causes of paraplegia, worldwide. Unfortunately, gains in the management of myelomeningocele have been mainly on antenatal diagnosis and prevention while efforts on understanding its cause, mechanisms involved are still tentative. Concerning the surgical management, no revolutionary modification improving outcome has been introduced unlike other fields of neurosurgery.Medical management of a child with myelomeningocele requires a lifelong effort of several disciplines including urology, orthopedics physical and social therapy besides neurosurgery. The initial and probably the most crucial step begin with proper repair of the lesion. The aim of surgery, with its simplest definition should be towards maintaining the medical condition of the newborn. In other words, consequences of an open spinal cord segment with associated malformations have to be avoided with appropriate measures. Comparable to the surgical treatment of any congenital malformation, myelomeningocele repair consist of reversing the failed steps of normal neural tube closure. This requires a thorough understanding of the normal and abnormal embryological sequence of events in formation of the spinal cord. Although the purpose of this chapter is to describe the basic concepts and technique of myelomeningocele repair, contemporary information and progress on epidemiology, and etiology and embryology is presented with discussion of controversial issues regarding the selection process, optimal time for surgery and technical modifications.

Prenatal versus postnatal repair procedures for spina bifida for improving infant and maternal outcomes

BACKGROUND

Spina bifida is a fetal neural tube defect (NTD), which may be diagnosed in utero and is compatible with life postnatally, albeit often with significant disability and morbidity. Although postnatal repair is possible, with increasing in utero diagnosis with ultrasound, the condition has been treated during pregnancy (prenatal repair) with the aim of decreased morbidity for the child. The procedure that is performed during pregnancy does have potential morbidities for the mother, as it involves maternal surgery to access the fetus.

OBJECTIVES

To compare the effects of prenatal versus postnatal repair and different types of repair of spina bifida on perinatal mortality and morbidity, longer term infant outcomes and maternal morbidity.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 July 2014).

SELECTION CRITERIA

All published, unpublished, and ongoing randomised controlled trials comparing prenatal and postnatal repair of meningomyelocele for fetuses with spina bifida and different types of prenatal repair.

DATA COLLECTION AND ANALYSIS

Two review authors independently evaluated trials for inclusion and methodological quality without consideration of their results according to the stated eligibility criteria and extracted data.

MAIN RESULTS

Our search strategy identified six reports for potential inclusion. Of those, we included one trial (four reports) involving 158 women, which was at low risk of bias.The one included trial examined the effect of prenatal repair versus postnatal repair. For the primary infant outcome of neonatal mortality, there was no clear evidence of a difference identified for prenatal versus postnatal repair (one study, 158 infants, risk ratio (RR) 0.51, 95% confidence interval (CI) 0.05 to 5.54), however event rates were uncommon and so the analysis is likely to be underpowered to detect differences.Prenatal repair was associated with an earlier gestational age at birth (one study, 158 infants, mean difference (MD) -3.20 weeks, 95% CI -3.93 to -2.47) and a corresponding increase in both the risk of preterm birth before 37 weeks (one study, 158 infants, RR 5.30, 95% CI 3.11 to 9.04) and preterm birth before 34 weeks (one study, 158 infants, RR 9.23, 95% CI 3.45 to 24.71). Prenatal repair was associated with a reduction in shunt dependent hydrocephalus and moderate to severe hindbrain herniation. For women, prenatal repair was associated with increased preterm ruptured membranes (one study, 158 women, RR 6.15, 95% CI 2.75 to 13.78), although there was no clear evidence of difference in the risk of chorioamnionitis or blood transfusion, although again, event rates were uncommon.A number of this review's secondary infant and maternal outcomes were not reported. For the infant: days of hospital admission; survival to discharge; stillbirth; need for further surgery (e.g. skin grafting); neurogenic bladder dysfunction; childhood/infant quality of life. For the mother: admission to intensive care; women's emotional wellbeing and satisfaction with care.

AUTHORS' CONCLUSIONS

This review is based one small well-conducted study. There is insufficient evidence to recommend drawing firm conclusions on the benefits or harms of prenatal repair as an intervention for fetuses with spina bifida. Current evidence is limited by the small number of pregnancies that have been included in the single conducted randomised trial to date.

Neural stem cells: are they the hope of a better life for patients with fetal-onset hydrocephalus?

I was honored to be awarded the Casey Holter Essay Prize in 2013 by the Society for Research into Hydrocephalus and Spina Bifida. The purpose of the prize is to encourage original thinking in a way to improve the care of individuals with spina bifida and hydrocephalus. Having kept this purpose in mind, I have chosen the title: Neural stem cells, are they the hope of a better life for patients with fetal-onset hydrocephalus? The aim is to review and discuss some of the most recent and relevant findings regarding mechanisms leading to both hydrocephalus and abnormal neuro/gliogenesis. By looking at these outcome studies, it is hoped that we will recognize the potential use of neural stem cells in the treatment of hydrocephalus, and so prevent the disease or diminish/repair the associated brain damage.

Anesthesia for in utero repair of myelomeningocele

Recently published results suggest that prenatal repair of fetal myelomeningocele is a potentially preferable alternative when compared to postnatal repair. In this article, the pathology of myelomeningocele, unique physiologic considerations, perioperative anesthetic management, and ethical considerations of open fetal surgery for prenatal myelomeningocele repair are discussed. Open fetal surgeries have many unique anesthetic issues such as inducing profound uterine relaxation, vigilance for maternal or fetal blood loss, fetal monitoring, and possible fetal resuscitation. Postoperative management, including the requirement for postoperative tocolysis and maternal analgesia, are also reviewed. The success of intrauterine myelomeningocele repair relies on a well-coordinated multidisciplinary approach. Fetal surgery is an important topic for anesthesiologists to understand, as the number of fetal procedures is likely to increase as new fetal treatment centers are opened across the United States.

Spinal cord malformations

Malformations of the spinal cord are one of the most frequent malformations. They should be clearly divided into two completely different families of malformations: open dysraphisms and occult dysraphisms. Open dysraphism mostly consists in myelomeningocele (MMC). Its incidence is 1/1000 live births with a wide variation. Folic acid supplementation has been shown to reduce its risk. In most cases, the diagnosis is done prenatally by serum screening and ultrasound and may lead to termination of pregnancy. In case of decision to continue pregnancy, surgical treatment must be achieved during the first days of life, and in 50 to 90% of cases, a ventricular shunt must be installed. The follow-up of these children must be continued throughout life looking for late complications (Chiari II and syringomyelia, vertebral problems, neuropathic bladder, tethered cord). Occult dysraphisms are a heterogeneous group of malformations. Lipomas (filum and conus) are the most frequent and their treatment remains controversial. Diastematomyelia, neurenteric cysts, dermal sinus, and more complex forms (Currarino syndrome) belong to this group. Most of them can and must be diagnosed prenatally or at birth by careful examination of the lower back for the cutaneous stigmata of the disease to decrease the risk of neurological, urological, or orthopedic permanent handicap.

Therapeutic potential of in utero mesenchymal stem cell (MSCs) transplantation in rat foetuses with spina bifida aperta

Neural tube defects (NTDs) are complex congenital malformations resulting from incomplete neurulation in embryo. Despite surgical repair of the defect, most of the patients who survive with NTDs have a multiple system handicap due to neuron deficiency of the defective spinal cord. In this study, we successfully devised a prenatal surgical approach and transplanted mesenchymal stem cells (MSCs) to foetal rat spinal column to treat retinoic acid induced NTDs in rat. Transplanted MSCs survived, grew and expressed markers of neurons, glia and myoblasts in the defective spinal cord. MSCs expressed and perhaps induced the surrounding spinal tissue to express neurotrophic factors. In addition, MSC reduced spinal tissue apoptosis in NTD. Our results suggested that prenatal MSC transplantation could treat spinal neuron deficiency in NTDs by the regeneration of neurons and reduced spinal neuron death in the defective spinal cord.

Pain assessment in human fetus and infants

In humans, painful stimuli can arrive to the brain at 20-22 weeks of gestation. Therefore several researchers have devoted their efforts to study fetal analgesia during prenatal surgery, and during painful procedures in premature babies. Aim of this paper is to gather from scientific literature the available data on the signals that the human fetus and newborns produce, and that can be interpreted as signals of pain. Several signs can be interpreted as signals of pain. We will describe them in the text. In infants, these signs can be combined to create specific and sensible pain assessment tools, called pain scales, used to rate the level of pain.

Is fetal pain a real evidence?

Due to the progress in fetal surgery, it is important to acquire data about fetal pain.

MATERIAL AND METHODS

We performed a Medline research from 1995, matching the following key words: "pain" and "fetus", with the following: "subplate", "thalamocortical", "myelination", "analgesia", "anesthesia", "brain", "behavioral states", "substance p". We focused on: (a) fetal development of nociceptive pathways; (b) fetal electrophysiological, endocrinological and behavioral reactions to stimuli and pain.

RESULTS

We retrieved 217 papers of which 157 were highly informative; some reported similar data or were only case-reports, and were not quoted. Most endocrinological, behavioral and electrophysiological studies of fetal pain are performed in the third trimester, and they seem to agree that the fetus in the 3rd trimester can experience pain. But the presence of fetal pain in the 2nd trimester is less evident. In favor of a 2nd trimester perception of pain is the early development of spino-thalamic pathways (approximately from the 20th week), and the connections of the thalamus with the subplate (approximately from the 23rd week). Against this possibility, some authors report the immaturity of the cortex with the consequent lack of awareness, and the almost continuous state of sleep of the fetus.

CONCLUSIONS

Most studies disclose the possibility of fetal pain in the third trimester of gestation. This evidence becomes weaker before this date, though we cannot exclude its increasing presence since the beginning of the second half of the gestation.

Human neural tube defects: genetic causes and prevention

Neural tube defects (NTDs) are severe congenital malformations affecting 1-2 in 1,000 live births, whose etiology is multifactorial, involving environmental and genetic factors. NTDs arise as consequence of the failure of fusion of the neural tube early during embryogenesis. NTDs' pathogenesis has been linked to genes involved in folate metabolism, consistent with an epidemiologic evidence that 70% of NTDs can be prevented by maternal periconceptional supplementation. However, polymorphisms in such genes are not linked in all populations, suggesting that other genetic factors and environmental factors could be involved. Animal models have provided crucial mechanistic information and possible candidate genes to explain susceptibility to NTDs. A crucial role has been assigned to the planar cell polarity (PCP) pathway, a highly conserved, non-canonical Wnt-frizzled-dishevelled signaling cascade that plays a key role in establishing and maintaining polarity in the plane of the epithelium and in the process of convergent extension during gastrulation and neurulation in vertebrates. The Loop-tail (Lp) mouse that develops craniorachischisis carry missense mutations in the PCP core gene Vangl2, that is the mammalian homolog of the Drosophila Strabismus/Van gogh (Stbm/Vang). The presence of mutations in human VANGL1 and VANGL2 genes encourages us to extend the investigation to other PCP genes that, with VANGL, play an essential role in neurulation during development.

MRI findings, surgical treatment and follow-up of a myelomeningocele with tethered spinal cord syndrome in a cat

A 7-month-old male neutered cat was referred for paraparesis and painful sensation at the level of T13 vertebra where a dermal cyst was observed. Spine radiographs and magnetic resonance imaging (MRI) showed a well-encapsulated cyst communicating with the meninges and spinal cord, suggestive of hydromyelia and myelodysplasia. Dorsal laminectomy was performed and the cyst was completely removed. The day after surgery, the cat was ambulatory paraparetic. Involuntary defecation was observed for only a few days. The surgical specimen was cystic and covered by skin. Microscopic examination revealed a hollow hemispheric mass of glial fibrillary acidic protein (GFAP)-positive neural tissue lined by ependyma and formed of glia and vascular structures consistent with myelomeningocele (MMC). Only anecdotal descriptions of MMC have been published in the veterinary literature, mainly in the lumbosacral spinal cord. To the authors' knowledge, this is the first report of a MMC with tethered spinal cord syndrome in a cat successfully treated surgically.

Fetal neurosurgery: current state of the art

Congenital CNS abnormalities have been targets for prenatal intervention since the founding of fetal surgery 30 years ago, but with historically variable results. Open fetal neurosurgery for myelomenigocele has demonstrated the most promising results of any CNS malformation. Improvements in the understanding of congenital diseases and in fetal surgical techniques have reopened the door to applying fetal surgery to other congenital CNS abnormalities. Advances in gene therapy, bioengineering and neonatal neuroprotection will aid in the future expansion of fetal neurosurgery to other CNS disorders.

Congenital myelomeningocele - do we have to change our management?

BACKGROUND

Eagerly awaiting the results of the Management of Myelomeningocele Study (MOMS) and with an increasing interest in setting up intrauterine myelomeningocele repair (IUMR), the optimal management of patients suffering from congenital myelomeningocele (MMC) has become a matter of debate again. We performed a cross-sectional study at our referral-center for MMC to determine the outcome for our expectantly managed patients.

MATERIALS AND METHODS

A computed chart review at our institution revealed 70 patients suffering from MMC. Forty-three patients were eligible for the study and analyzed further. A retrospective analysis was performed only in patients that underwent MMC repair within the first two days of life and were seen at our outpatient clinic between 2008 and 2009 for a regular multidisciplinary follow-up. Data were collected on: gestational age (GA) and weight at birth, age at shunt placement and shunt status after the first year of life, radiological evidence for Arnold-Chiari malformation (ACM) and tethered cord (TC), need for surgery for TC, bladder function, lower leg function and educational level. Data were compared to published results for IUMR and to studies of historical controls.

RESULTS

Patients were born with MMC between 1979 and 2009 and are now 13.3 ± 8.9 (mean ± SD) years of age. At birth, mean GA was 37.8 ± 2.3 weeks and mean weight was 2921.3 ± 760.3 g, both significantly higher than in IUMR patients. Shunt placement in our cohort was required in 69.8% at a mean age of 16.0 ± 10.7 days, which was less frequent than for historical controls. Amongst our cohort, radiological observations showed 57.1% had ACM II and 41.9% had TC. Only two of our patients underwent a surgical correction for TC. Clean intermittent catheterization was performed in 69.7% of our patients, 56.4% were (assisted) walkers and 64.1% attended regular classes, both comparable to historical controls.

CONCLUSIONS

With a close and interdisciplinary management by pediatric surgeons, neurologists and urologists, the long-term outcome of patients suffering from MMC can currently be considered satisfactory. With respect to the known drawbacks of fetal interventions for mother and child, especially preterm delivery, the results of the MOMS trial should be awaited with caution before proceeding with a complex intervention like IUMR.

Supratentorial abnormalities in the Chiari II malformation, III: The interhemispheric cyst

OBJECTIVE

Our clinical observations noted an interhemispheric "cyst," a protrusion of the posterior superior third ventricle, in fetuses with myelomeningocele (MMC). The study analyzed the frequency of this observation and features that influence its visualization.

METHODS

We searched for cases of fetal MMC sonographically detected between 1999 and 2007. Intracranial findings were retrospectively reviewed with attention to the interhemispheric cistern. Additionally, we reviewed 25 fetuses without a central nervous system anomaly and 10 fetuses with ventriculomegaly but no MMC.

RESULTS

Among 89 fetuses identified, the mean gestational age was 22 weeks 4 days. Thirty-eight (43%) had an interhemispheric cyst. The frequency was similar on sonograms judged to be well visualized compared with studies judged to be suboptimally visualized. The degree of ventriculomegaly, timing of diagnosis, and severity of the Chiari II malformation did not appear to influence the frequency of the finding. Among fetuses without a central nervous system anomaly, no interhemispheric cysts were detected; a cyst was detected in 1 of 10 fetuses with ventriculomegaly. Interhemispheric cysts were more likely to be detected in fetuses with the Chiari II malformation than fetuses with ventriculomegaly but without the Chiari II malformation (P = .04).

CONCLUSIONS

Interhemispheric cysts are a common supratentorial feature of the Chiari II malformation. Their presence appears to be unrelated to other features of the Chiari II malformation. Although interhemispheric cysts are seen in other abnormal fetuses, their striking prevalence in the Chiari II malformation should lead to a thorough examination for MMC.

The changing incidence of myelomeningocele and its impact on pediatric neurosurgery: a review from the Children's Memorial Hospital

INCIDENCE

Worldwide, the incidence of neural tube defects (NTDs) varies from 0.17 to 6.39 per 1,000 live births. The declining prevalence of myelomeningocele, the most common NTD, is secondary to several factors including folic acid fortification, prenatal diagnosis with termination of affected fetuses, and unknown factors.

IMPACT OF CHANGES

Of those born with myelomeningocele, survival during infancy and preschool years has improved over the last 25 years (Bowman et al., Pediatr Neurosurg 34:114-120). Fewer newborns today require shunt placement, which will hopefully improve the long-term mortality associated with this disease (Chakraborty et al., J Neurosurg Pediatr 1(5):361-365, unpublished data). Of a cohort born in 1975-1979 and treated at a single US institution, 74% have survived into young adulthood.

CLINICAL IMPLICATIONS

One of the greatest challenges facing these young adults is the transitioning of their medical care into an adult medical community.

Simplified correction of a meningomyelocele-like defect in the ovine fetus

PURPOSE: To develop a simplified technique for antenatal correction of a meningomyelocele -like defect in fetal sheep to allow direct skin closure. METHODS: A spinal defect was surgically created at 75 days of gestation in the fetuses of 36 pregnant sheep, 23 survived the surgery. At 102 days gestation, the defect was corrected in 14 cases (9 were left untreated). Skin surrounding the defect was dissected below the dermis to permit its edges to be approximated and sutured, without interposing any material to its edges. An interface material intended to protect the neural tissue from skin adhesion was used and the skin defect was completely closed over it. Pregnancy was allowed to continue up to 138 days gestation, the fetuses were submitted to macroscopic and microscopic analysis. RESULTS: The defect was successfully corrected in 90.9% in the experimental group, and spontaneous closure occurred in 22.3% in the control group (p < 0.05). The survival rate after the creation and correction of the defect was 63.4% and 78% respectively. CONCLUSION: This simplified technique was successful in the correction a meningomyelocele-like defect, in the fetal sheep.

Prenatal diagnosis, fetal surgery, recurrence risk and differential diagnosis of neural tube defects

Prenatal screening with alpha-fetoprotein (AFP) and ultrasonography have allowed the prenatal diagnosis of neural tube defects (NTDs) in current obstetric care, and open spina bifida has been considered a potential candidate for in utero treatment in modern pediatric surgery. This article provides an overview of maternal serum AFP screening, amniotic fluid AFP assays, amniotic fluid acetylcholinesterase immunoassays and level II ultrasound for NTDs, prenatal repair of fetal myelomeningocele, recurrence risk of NTDs, and differential diagnosis of NTDs on prenatal ultrasound.

Supratentorial abnormalities in the Chiari II malformation, II: tectal morphologic changes

OBJECTIVE

The sonographic diagnosis of fetal myelomeningocele has improved mainly because the diagnostic focus has shifted from observation of spinal manifestations to observation of cranial abnormalities. Intracranial diagnostic criteria rely on abnormalities in the posterior fossa. We describe abnormalities in tectal morphologic characteristics that, although well described on magnetic resonance imaging, have received little attention in the sonographic literature. This study analyzed the frequency of this observation and technical aspects that improve its visualization.

METHODS

From a database of obstetric sonograms, we identified all cases of sonographically detected myelomeningocele. The search covered the years 1999 to 2007. We retrospectively reviewed the fetal intracranial findings with special attention to elongation or "beaking" of the tectum.

RESULTS

A total of 89 fetuses were identified. The mean and median gestational ages were 22 weeks 4 days and 22 weeks 2 days, respectively. Of the 89 cases, 59 (66%) had an abnormal tectal shape. The abnormality was seen in 77% of cases judged to be suboptimally visualized and 62% of cases with good visualization. Tectal abnormalities were seen equally well in fetuses before and after 24 weeks. Finally, tectal abnormalities were seen more frequently as the severity of posterior fossa findings increased.

CONCLUSIONS

Tectal morphologic alteration is a common supratentorial feature of the Chiari II malformation on prenatal sonography both before and after 24 weeks' gestation. Its frequency increases with the severity of posterior fossa abnormalities. Therefore, it may be useful as a supratentorial indicator of both the presence and, potentially, the severity of the Chiari II malformation.

Congenital malformations of the central nervous system: clinical approach

Central nervous system (CNS) malformations represent important factor of morbidity and mortality in children. The aim of the study was to determine the incidence, type and clinical features of CNS malformations in children who were admitted at the Neonatal and Child Neurology Department, Neonatal Intensive Care Unit and Paediatric Intensive Care Unit of Paediatric Clinic, University of Sarajevo Clinics Centre, from January 1st, 2002 to December 31st, 2006. There were total of 16520 admissions at the Paediatric Clinic over the studied period. CNS malformations, solitary or multiple, have been diagnosed in 100 patients (0,61%). The total number of various CNS malformations was 127. Lethal outcome was established in 9/100 cases (9%). The most frequent CNS malformations were neural tube defects 49/127 (38,6%). Hydrocephalus was seen in 34/127 (26,8%), microcephaly in 24/127 (18,9%), agenesis of corpus callosum in 10/127 (7,9%), Dandy Walker malformation in 6/127 (4,7%) and other CNS malformations in 4/127 (3,1%). In 20/100 of patients neural tube defect was associated with hydrocephalus (20%). CNS malformations were prenatally diagnosed in 13/100 of patients (13%). Primary prevention of CNS malformations can be improved in our country by better implementation of preconceptional folic acid therapy for all women of childbearing age. Secondary prevention by prenatal diagnosis requires advanced technical equipment and adequate education of physicians in the field of foetal ultrasonography. In our circumstances, prenatal diagnostics of CNS malformations is still not developed enough.

Vascular and apoptotic changes in the placode of myelomeningocele mice during the final stages of in utero development

OBJECT

Myelomeningocele (MMC) is a primary neurulation defect that is associated with devastating neurological disabilities in affected newborns. To better characterize the in utero neurodegenerative process of MMC, the authors investigated the changes in vascular organization, apoptosis, and the presence of inflammatory cells during gestation by using a mutant mouse model of MMC.

METHODS

The curly tail/loop tail (ct/lp) mutant mouse model of MMC was chosen to obtain fetuses at different stages of gestation. Mouse fetuses harboring MMC were harvested by caesarean section at embryonic Days 14.5, 16.5, and 18.5 (complete mouse gestation at 19 days, 6 mice/group); littermate fetuses with the same gestational age but without an MMC were used as controls. Samples of the MMC placode or normal spinal cord were stained for immunocytochemical labeling with caveolin antibody (endothelium marker) and activated caspase-3 antibody (apoptosis marker). Samples were morphometrically analyzed with a computer-assisted image analyzer.

RESULTS

The MMC mice presented with an increase in vascular density from embryonic Days 16.5-18.5 and an enhanced number of apoptotic cells at embryonic Day 18.5, compared with controls. There were scarce signals of an inflammatory reaction in the MMC placode, as a few infiltrating neutrophils were seen only at embryonic Day 18.5.

CONCLUSIONS

Fetal placodes in MMC mice showed evidence of increased vascular density since embryonic Day 16.5 and increased apoptosis at embryonic Day 18.5. These new data support the view that in utero changes of the MMC placode, occurring during the last stages of gestation, contribute to the neuropathological manifestations in full-term newborns with MMC.

Spinal hemorrhages are associated with early neonatal motor function loss in human spina bifida aperta

BACKGROUND

In spina bifida aperta (SBA), leg movements caudal to the meningomyelocele are present in utero, but they disappear shortly after birth. It is unclear whether leg movements disappear by impact of the neuro-developmental malformation or by superimposed traumatic damage. If superimposed traumatic damage is involved, targeted fetal intervention could improve motor outcome.

AIM

To characterize neuromuscular pathology in association with perinatal motor function loss in SBA.

PATIENTS/METHODS

In fetal SBA (n=8; 16-40 weeks GA), the median time interval between ultrasound registrations of fetal motor behavior and post-mortem histology was 1 week. Histology was assessed cranial, at and caudal to the meningomyelocele and compared with findings in fetal controls (n=4).

RESULTS

Despite fetal movements caudal to the meningomyelocele (5/6), histology indicated muscle fiber alterations (6/6) that concurred with neuro-developmental and traumatic spinal defects [Neuro-developmental defects: spinal ependymal denudation (3/8), reduced amount of (caspase3-negative) lower motor neurons (LMNs; 8/8), aberrant spinal vascularization (8/8). Traumatic defects: gliosis (7/8), acute/fresh spinal hemorrhages near LMNs (8/8)].

CONCLUSION

In all delivered SBA patients, recent spinal hemorrhages were superimposed upon pre-existing defects. If early therapeutic strategies can prevent these superimposed secondary spinal hemorrhages, motor outcome may improve.