MMC Closure Research Articles

Neurosurgical management of Myelomeningocele in premature infants: a case series

IntroductionMyelomeningocele (MMC) is the most common neural tube defect, but rarely seen in premature infants. Most centers advocate for closure of MMC within 24 h of birth. However, this is not always possible in severely premature infants. Given the rarity of this patient population, we aimed to share our institutional experience and outcomes of severely premature infants with MMC.MethodsWe performed a retrospective, observational review of premature infants (≤ 32 weeks gestational age) identified through our multidisciplinary spina bifida clinic (1995–2021) and surgical logs. Descriptive statistics were compiled about this sample including timing of MMC closure and incidence of adverse events such as sepsis, CSF diversion, meningitis, and death.ResultsEight patients were identified (50% male) with MMC who were born ≤ 32 weeks gestational age. Mean gestational age of the population was 27.3 weeks (SD 3.5). Median time to MMC closure was 1.5 days (IQR = 1—80.8). Five patients were taken for surgery within the recommended 48 h of birth; 2 patients underwent significantly delayed closure (107 and 139 days); and one patient’s defect epithelized without surgical intervention. Six of eight patients required permanent cerebrospinal fluid (CSF) diversion (2 patients were treated with ventriculoperitoneal shunting (VPS), three were treated with endoscopic third ventriculostomy (ETV) with choroid plexus cauterization (CPC) and 1 patient treated with ETV; mean of 3 years after birth, ranging from 1 day to 16 years). Two patients required more than one permanent CSF diversion procedure. Two patients developed sepsis (defined as meeting at least 2/4 SIRS criteria). In both cases of sepsis, patients developed signs and symptoms more than 72 h after birth. Notably, both instances of sepsis occurred unrelated to operative intervention as they occurred before permanent MMC closure. Two patients had intraventricular hemorrhage (both grade III). No patients developed meningitis (defined as positive CSF cultures) prior to MMC closure. Median follow up duration was 9.7 years. During this time epoch, 3 patients died: Two before 2 years of age of causes unrelated to surgical intervention. One of the two patients with grade III IVH died within 24 h of MMC closure.ConclusionsIn our institutional experience with premature infants with MMC, some patients underwent delayed MMC closure. The overall rate of meningitis, sepsis, and mortality for preterm children with MMC was similar to MMC patients born at term.

Impact of dual procedures: How combining VP shunt placement for hydrocephalus and myelomeningocele repair in newborns affects complication rates?

To discern the efficacy of simultaneous versus delayed VPS surgery in managing hydrocephalus linked with MMC repair: The debate over the concurrent or deferred placement of ventriculoperitoneal shunts (VPS) during myelomeningocele (MMC) repair in hydrocephalic neonates necessitates a nuanced evaluation of associated risks and benefits. While VPS placement can mitigate cerebrospinal fluid (CSF) leaks and minimize wound dehiscence post-MMC repair, it concurrently introduces potential hazards such as infections and shunt-related malfunctions. This prospective cohort study focused on144 newborns with spinal myelomeningocele and hydrocephalus. Divided into two groups based on the timing of dysraphism repair and VPS placement, 101 children underwent concurrent procedures, while 43 received deferred VPS insertion post-MMC closure. Female patients constituted 60% of the cohort, with lumbar lesions being predominant. The median age for MMC closure was three days. Analysis revealed that the deferred insertion group exhibited higher rates of shunt malfunctions, CSF leaks, and wound dehiscence compared to the concurrent insertion group. Although indications hinted at a potential increase in shunt infections in the immediate insertion group, statistical significance was lacking. The study established a statistically significant association between the timing of shunt insertion during MMC repair and specific outcomes, such as CSF leaks and wound dehiscence. The findings suggest that concurrent shunt insertion during MMC repair may reduce the incidence of these complications compared to deferred insertion. However, no substantial differences emerged in terms of shunt infection and malfunction, emphasizing the persistent challenges associated with these major complications.

Postnatal myelomeningocele closure in smallest reported neonate: illustrative case.

Myelomeningocele (MMC) is the most serious form of spina bifida, a congenital defect in neural tube development. Defect closure in a patient with an extremely low birth weight presents unique challenges and risks; lower birth weight is associated with multiple organ system concerns, homeostasis is difficult, and local tissue is underdeveloped. To the authors' knowledge, the present case is the lowest reported weight (490 g) for a neonate with postnatal MMC repair. A preterm male with a prenatally diagnosed lumbosacral MMC and associated Chiari malformation type II was born at 23 weeks 1 day to a 29-year-old mother, gravidity 6 parity 4. The patient was medically stabilized and underwent MMC closure on day of life 5. His weight was 490 g at the time of this repair, and he did not have any surgical complications. At age 16 months, he underwent endoscopic third ventriculostomy with choroid plexus cauterization; he has not required any further hydrocephalus treatments since the last follow-up at 30 months of age. To the authors' knowledge, this case is the lowest birth weight ex utero MMC closure reported in the literature. Challenges of prematurity and size required appropriate preoperative stabilization, careful hemostasis and temperature regulation, and meticulous surgical technique.

Micro-Surgical Treatment of Fetal Myelomeningocele

Abstract Introduction Myelomeningocele (MMC) is the most common malformation of the central nervous system compatible with life. We will report the results obtained with the prenatal closure of MMC at the Instituto Estadual do Cérebro Paulo Niemeyer (IECPN). Objectives Clinical outcome of fetuses undergoing intrauterine MMC repair by the Peralta mini-hysterotomy. Monitor the reduction of Arnold-Chiari II secondary to MMC, reduction of hydrocephalus and also motor development in these children. Methods Descriptive study of 26 cases with intrauterine MMC repair by mini-hysterotomy, or Peralta technique, performed at the IECPN from December 2017 to February 2020. Results Between December 2017 and February 2020, 26 pregnant women with children with MMC were operated on using Peralta technique. Fetuses were born at an average gestational age of 34.2 weeks and 8% were born before 30 weeks of gestation. The average birth weight was 2096g. It was possible to observe a significant reduction in the occurrence of Arnold-Chiari II in these patients, as well as an evident improvement in motor function in the neurological examination of these babies at the end of the first month of life, where 20 of 23 babies had active movement in the lower limbs. Discussion This study demonstrates the correction of fetal MMC through a mini-hysterotomy of 2.5 to 3.5 cm, developed in order to reduce maternal and fetal mortality. This mini-hysterotomy technique is not a minimally invasive procedure, as it is based on open surgery for the treatment of fetal MMC, as recommended by the Management of Myelomeningocele Study (MOMS).

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.

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.

Shunt infection and malfunction in patients with myelomeningocele.

Myelomeningocele (MMC) is frequently complicated by symptomatic hydrocephalus, necessitating early permanent CSF diversion and revision surgeries. Shunt infections are a common cause of shunt malfunction. This study aims to characterize long-term shunt-related outcomes of patients undergoing MMC closure. A total of 170 patients undergoing MMC closure between the years of 1995 and 2017 were identified from a retrospective review of a prospectively populated surgical database at the Children's Hospital of Pittsburgh. Patients who underwent MMC closure and required ventriculoperitoneal (VP) shunt insertion met criteria and were included in the primary study analysis. Analysis with a Fisher exact test was performed for categorical variables, and Mann-Whitney U-tests were utilized for numerical data. Of the 158 total patients undergoing MMC closure and meeting inclusion criteria, 137 (87%) required VP shunt insertion. These 137 patients demonstrated a shunt revision rate of 21.1% per person-year and a shunt infection rate of 2.1% per person-year over a mean follow-up of 10.8 years. Patients had a mean of 3.4 ± 0.6 shunt surgeries prior to their first infection. Patients undergoing immediate shunt removal, external ventricular drain placement, or shunt replacement after clearing the infection had lower rates of subsequent infections than patients who initially were managed with shunt externalization (p < 0.001). Placement of a shunt at the time of MMC closure was not found to be a risk factor for infection. Of patients with initial shunt placement after the implementation of the Hydrocephalus Clinical Research Network protocol in 2011, the authors' institution has had a shunt infection rate of 4.2% per person-year and a revision rate of 35.7% per person-year. This study describes long-term outcomes of shunted MMC patients and factors associated with shunt infections. Most patients underwent multiple revisions prior to the first shunt infection. Shunt externalization may be ineffective at clearing the infection and should be avoided in favor of early shunt removal and external ventricular drainage, followed by shunt replacement once infection is demonstrated to have cleared.

Fully percutaneous fetoscopic repair of myelomeningocele: 30-month follow-up data.

This observational study reports on the postnatal mortality and 30-month outcome of children who underwent fully percutaneous fetoscopic repair of myelomeningocele (MMC) at a single center in Giessen, Germany. Between October 2010 and August 2014, a total of 72 patients underwent fully percutaneous fetoscopic MMC closure at 21 + 0 to 29 + 1 (mean, 23 + 5) weeks' gestation. Of these, 52 (72%) participated in this study; however, 30-month mortality data are available for all 72 children. Children were examined at four timepoints: shortly after birth and at 3 months, 12 months and 30 months of corrected age. The patients underwent age-specific standardized neurological examinations and assessment of leg movements and ambulation at all timepoints. Cognitive and motor development were assessed using the Bayley Scales of Infant Development, second edition (BSID-II), at 30 months. All 72 children survived the intrauterine procedure, however, four (5.6%) infants died postnatally (including two of the 52 comprising the study cohort). Of the 52 patients included in the study, 11.5% were delivered before the 30th week of gestation (mean, 33 + 1 weeks) and, of the survivors, 48.1% had ventriculoperitoneal shunt placement. Of the 50 infants that were alive at 30 months, independent ambulation, without orthosis, was feasible for 46%. At 30 months of follow-up, 46% of children presented with a functional level that was at least two segments better than the anatomical level of the lesion. At 30 months, 70% of the children presented with BSID-II psychomotor development index score of ≥ 70 and 80% with BSID-II mental development index score of ≥ 70. Intrauterine repair of MMC by percutaneous fetoscopy shows largely similar outcomes to those reported for open repair, with respect to mortality, prematurity, shunt-placement rates, motor and mental development and free ambulation. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Myelomeningocele Closure: An Embryological Perspective.

Myelomeningoceles (MMCs) represent a localized failure of primary neurulation during the fourth week of embryonic development. There are a number of misconceptions concerning the proper identification, classification, and surgical repair of these lesions. To provide surgeons with a working knowledge of early neural embryology as it relates to MMC closure as a localized failure of primary neurulation. We review the embryology of early neural development as a means of providing neurosurgeons with a better understanding of MMC closure techniques. Early neural development predicts the anatomy of MMC and knowledge of embryology helps guide repair. Repair of MMC is enhanced by knowing early neural development.

Reduced rates of infection after myelomeningocele closure associated with standard perioperative antibiotic treatment with ampicillin and gentamicin.

Postnatal closure of a myelomeningocele (MMC) is a complex procedure with frequent complications following surgery. Bacterial colonization of the placode may cause infection and subsequent complications. The objectives of this study were to determine the preoperative bacterial colonization rates, to assess the antibiotic regimen, and to evaluate the overall postoperative infection rate. All consecutive patients undergoing MMC closure in our hospital from January 2010 to January 2020 were evaluated. Epidemiological data, surgical data, complication characteristics, and microbiological results were documented. A total of 45 patients were evaluated; in 41 patients, a wound swab of the placode was performed directly before MMC closure (91%). All patients received a prophylactic antibiotic treatment for a mean of 5.6 ± 2.7days around the performed MMC closure. In three patients with a wound swab (7.3%), a bacterial colonization could be detected-none of the patients developed a subsequent infection. Overall, 7 other patients developed an infection (15.6%), three local surgical site infections, and four shunt-related infections. After applying a standardized perioperative prophylactic antibiotic treatment with ampicillin and gentamicin, the infection rate was observed to be lower compared with that of a non-standardized treatment (6% vs. 45%; p = 0.019). In neonates who undergo MMC closure in the first 48h after birth, the colonization rate of the placode was lower than previously reported. While the data presented cannot proof the benefit of a perioperative antibiotic prophylaxis, as compared with no prophylaxis, infection rates are low with a standardized antibiotic regime comprising ampicillin and gentamicin.

817: Perinatal outcomes after fetal resuscitation during fetal MMC closure

Fetal complications including extreme prematurity are known risks of fetal myelomeningocele (fMMC) closure. The objective of this study was to evaluate the rate of fetal resuscitation during fMMC closure, including incidence of delivery and evaluation of neonatal outcomes in these cases. An international multicenter registry was created to track and report maternal, obstetric, and fetal/neonatal outcomes for cases of open maternal-fetal surgery for MMC closure. Data are collected from each center and entered into a combined de-identified dataset using REDCap. Fetal resuscitation was defined as need for chest compression, fetal medication or transfusion. Intraoperative and neonatal outcomes in cases requiring fetal resuscitation were analyzed using descriptive statistics. Centers participating in the registry have obtained local IRB approval and executed data use agreements. A total of 750 cases of fMMC closure have been entered into the registry. Of those, fetal resuscitation was required in 14 cases (1.9%). Of the 14 resuscitation cases, 12received fetal medications, 8 received chest compressions, and 4 received fetal transfusion. For these 14 cases, median gestational age at the time of fetal surgery was 24.4 weeks (range 22.6-25.9) and median gestational age at delivery was 31.8 weeks (range 23.7-37.3). Of these, 4 were delivered on the day of maternal-fetal surgery and 1 was delivered within 1 week of maternal-fetal surgery. Four out of 14 resulted in perinatal death (29%). All 4 of these were delivered within 1 week of maternal-fetal surgery. Only 1 out of 5 that required delivery survived. Need for fetal resuscitation during fMMC closureis uncommon, with the need for immediate delivery being a rare event. Survival is poor when delivery is required. This data is useful for counseling patients prior to the procedure and can be helpful with complex decisions regarding neonatal resuscitation efforts.

585: Fetal MMC Closure Stratified by Maternal BMI: a sub-analysis of the MOMS trial cohort

Obesity is a known risk factor for many obstetric complications. However, little is known about the impact of increased maternal BMI on outcomes of maternal-fetal surgery for myelomeningocele closure. The objective of this study was to evaluate operative, obstetric and neonatal outcomes stratified by maternal BMI for the cohort of patients who underwent open fetal surgery in the MOMS trial. This study is a sub analysis of data collected from the multicenter, randomized prospective MOMS trial comparing open maternal fetal surgery for MMC closure compared to routine neonatal closure. Only the women who underwent maternal-fetal surgery were included. Outcomes were compared based on maternal BMI: normal BMI/overweight BMI < 30 and obese with BMI 30-34.99. Data analyzed included maternal demographics, preoperative factors, length of surgery, obstetric and neonatal outcomes. Statistical analysis included Fisher’s exact test for categorical variables and t-tests for continuous variables. 91 women underwent fetal surgery in the original trial. Of those, 74 had BMI < 30 and 17 had BMI 30-34.99. Results are presented in the Table. There were no significant differences in maternal demographics, preoperative factors, obstetric complications, or gestational age at delivery. Preoperative factors were similar between the two groups except for the measurement of ventricle on the downside being larger in the BMI 30-34.99 BMI group (14.2 mm versus 11.3 mm, p=0.007). Neonatal outcomes were similar between the two groups, except for the greater need for shunt at 12 months in the 30-34.99 BMI group (70.6% versus 37.8%, p=0.028) consistent with the larger ventricle size. Maternal BMI in the obese range is not associated with increased maternal or obstetric risk for women undergoing open fetal surgery for MMC closure. There does not appear to be an effect of increased maternal BMI on neonatal outcomes, except for preoperative ventricle size and the need for shunt, which may be related to the small number and requires additional study.

Concepts in the neurosurgical care of patients with spinal neural tube defects: An embryologic approach.

The neural tube defects (NTDs) are a heterogeneous group of structural birth defects that arise from a complex array of multiple genetic and environmental factors and adversely affect the structure and function of the brain and spinal cord. Spinal NTDs are clinically more common than cranial NTDs. There remains a significant gap in linking the multiple NTD phenotypes to current genomic understanding. This article summarizes the neurosurgical clinical approach to spinal NTDs by correlating each step of embryonic development of the human nervous system with key management concepts for defects that arise at that step. The NTDs are broadly classified as open or closed. Open defects include myelomeningocele (MMC), encephalocele, and anencephaly. Closed defects are also known as occult spinal dysraphism and are characterized by intact skin over the spinal defect. They are more common and often cause neurologic decline from tethered cord syndrome. Failure of primary neurulation gives rise to open myelomeningocele (MMC). Surgical closure of an open MMC focuses on realigning the tissue layers that failed to separate during neurulation. In utero closure is a promising recent technique. Chronic neurosurgical management largely focuses treating hydrocephalus. The Chiari II malformation is uniformly present in MMC patients and may cause brainstem dysfunction. Tethered spinal cord may progressively impair normal neurologic function but typically responds well to surgical untethering. Surgical closure of MMC centers on approximated realignment of embryologically disordered neural tissue. Clinical surgical management decisions in the spinal NTDs remains challenging but standardized principles have emerged.

Cost of prenatal versus postnatal myelomeningocele closure for both mother and child at 1 year of life.

Prenatal myelomeningocele (MMC) closure has been performed in the United States for 2 decades. While prior work has focused on clinical outcomes of prenatal MMC closure, the cost of this procedure in comparison with that of postnatal MMC closure is unclear. The authors' aim was to compare the cost of prenatal versus postnatal MMC closure for both the child and mother at 1 year. A prospective database of patients undergoing prenatal and postnatal MMC closure between 2011 and 2018 with 1-year follow-up was retrospectively reviewed. Charge data for relevant admissions were converted to a cost estimate using the authors' institution's Medicare hospital-specific cost-to-charge ratio. Children, mothers, and mother/child pairs were considered separately. The primary outcome was cost. Secondary outcomes included the need for hydrocephalus treatment, length of stay (LOS), and readmissions. Other covariates included gestational age at birth, MMC lesion level, and obstetric complications. The median cost of care for children in the prenatal group was greater, although not significantly so, at $58,406.71 (IQR $16,900.24-$88,951.01) compared with $49,889.95 (IQR $38,425.18-$115,163.86) for children in the postnatal group (p = 0.204). The median cost for mothers in the prenatal group was significantly greater at $24,548.29 (IQR $20,231.55-$36,862.31) compared with $5087.30 (IQR $4430.72-$5362.56) (p < 0.001). The median cost for mother/child pairs in the prenatal group was $102,377.75 (IQR $37,384.30-$118,527.74) compared with $55,667.82 (IQR $42,840.78-$120,058.06) (p = 0.45). Children in the prenatal group had a lower gestational age at birth (235.81 days vs 265.77 days, p < 0.001) and fewer readmissions (33.3% vs 72.7%, p < 0.001), and hydrocephalus treatment was less common (33.3% vs 90.9%, p < 0.001). Index LOS did not differ between children in the prenatal and postnatal groups (26.8 days vs 23.5 days, p = 0.63). Mothers in the prenatal group had longer LOS (15.92 days vs 4.68 days, p < 0.001) and more readmissions (18.5% vs 0.0%, p = 0.06). The median cost of prenatal versus postnatal MMC closure did not significantly differ from a hospital perspective at 1 year, although variability in cost was high for both groups. When considering the mother alone, prenatal MMC closure was costlier. Future work is needed to assess cost from a patient and societal perspective both at 1 year and beyond.

Myelomeningocele-associated hydrocephalus: nationwide analysis and systematic review.

Myelomeningocele (MMC), the most severe form of spina bifida, is characterized by protrusion of the meninges and spinal cord through a defect in the vertebral arches. The management and prevention of MMC-associated hydrocephalus has evolved since its initial introduction with regard to treatment of MMC defect, MMC-associated hydrocephalus treatment modality, and timing of hydrocephalus treatment. The Nationwide Inpatient Sample (NIS) database from the years 1998-2014 was reviewed and neonates with spina bifida and hydrocephalus status were identified. Timing of hydrocephalus treatment, delayed treatment (DT) versus simultaneous MMC repair with hydrocephalus treatment (ST), and treatment modality (ETV vs ventriculoperitoneal shunt [VPS]) were analyzed. Yearly trends were assessed with univariable logarithmic regression. Multivariable logistic regression identified correlates of inpatient shunt failure. A PRISMA systematic literature review was conducted that analyzed data from studies that investigated 1) MMC closure technique and hydrocephalus rate, 2) hydrocephalus treatment modality, and 3) timing of hydrocephalus treatment. A weighted total of 10,627 inpatient MMC repairs were documented in the NIS, 8233 (77.5%) of which had documented hydrocephalus: 5876 (71.4%) were treated with VPS, 331 (4.0%) were treated with ETV, and 2026 (24.6%) remained untreated on initial inpatient stay. Treatment modality rates were stable over time; however, hydrocephalic patients in later years were less likely to receive hydrocephalus treatment during initial inpatient stay (odds ratio [OR] 0.974, p = 0.0331). The inpatient hydrocephalus treatment failure rate was higher for patients who received ETV treatment (17.5% ETV failure rate vs 7.9% VPS failure rate; p = 0.0028). Delayed hydrocephalus treatment was more prevalent in the later time period (77.9% vs 69.5%, p = 0.0287). Predictors of inpatient shunt failure included length of stay, shunt infection, jaundice, and delayed treatment. A longer time between operations increased the likelihood of inpatient shunt failure (OR 1.10, p < 0.0001). However, a meta-analysis of hydrocephalus timing studies revealed no difference between ST and DT with respect to shunt failure or infection rates. From 1998 to 2014, hydrocephalus treatment has become more delayed and the number of hydrocephalic MMC patients not treated on initial inpatient stay has increased. Meta-analysis demonstrated that shunt malfunction and infection rates do not differ between delayed and simultaneous hydrocephalus treatment.

Using the keystone design perforator island flap in large myelomeningocele closure.

Many repair techniques have been proposed to treat large myelomeningocele (MMC), and although effective in many cases, some of these techniques can be complex and time consuming, with complications such as cerebrospinal fluid (CSF) leakage, flap loss, tip necrosis, and wound dehiscence. The purpose of this study was to analyze cases of large skin defects and the methods applied and to report the outcomes of the keystone design perforator island flap (KDPIF) technique for large MMC closure. The authors performed a retrospective review of all neonatal patients who had undergone KDPIF for MMC closure in the period from 2013 to 2018. All patients had a diagnosis of lumbosacral MMC based on obstetric ultrasound. The neurosurgeons and plastic surgeons had selected the cases after concluding that primary closure would be unlikely. The design of the flap is based on the randomly located vascular perforators, creating two identical opposing flaps to fashion a double keystone flap. During wound closure, V-Y advancement of each end of the double flap in the longitudinal axis creates redundancy in the central portion of the flap and reduces the horizontal tension. After discharge, both the neurosurgery and plastic surgery teams followed up all patients, tracking the results with photography. No skin flap dehiscence or necrosis, infection, or CSF leakage was detected, proving the reliability of the flap. One of the patients required further surgery for the large skin defects after insufficient intrauterine closure of the MMC and successfully underwent KDPIF treatment. Another patient (14.3%) had severe neonatal sepsis, which ultimately led to death. A ventriculoperitoneal shunt was required after the skin defect repair in 5 (83.3%) of the 6 surviving patients. Exceptional aesthetic results were achieved for all patients during the follow-up. The KDPIF technique is based on well-known vascular perforators of the intercostal, lumbar, and gluteal regions. Wound tension is widely distributed by the flap and, as a consequence, relevant tissue bulk, reliable vascularity, and important geometrical versatility are provided. In addition, most of the muscles and fascia are preserved, which is another advantage in terms of minimizing secondary morbidity to local tissue rearrangement. The use of KDPIF closure was successfully shown to be a viable alternative for more complex MMCs that present with large skin defects.

Kyphectomy in Myelomeningocele for Severe Early-Onset Kyphosis Using Distal Intravertebral Fixation and Thoracic Growing Rods

Background:Most kyphectomy techniques require distal dissection of the bifid posterior spinal elements for implants placement in the thoracolumbar/pelvic regions, traversing the scarred tissue associated with previous MMC closure, thereby theoretically increasing the risk of wound complications. The Halifax kyphectomy technique avoids the MMC scar but does not reliably facilitate thoracic growth for early-onset kyphosis. This study aims to report the technique and outcomes of a combined Halifax kyphectomy (resection of the apical vertebrae with distal anterior multilevel vertebral body fixation) and thoracic growing rod construct used to treat early-onset symptomatic gibbus in a patient with myelomeningocele (MMC).Methods:A 3-year-old girl with a thoracic MMC presented with symptomatic gibbus requiring surgical intervention. Correction by the Halifax kyphectomy technique combined with spine-based growing rods was performed.Results:After the correction, the skin was closed primarily without the need for any flap for coverage. No wound complications or infection occurred post-operatively. The intraoperative blood loss was 200 mL, and the surgical time was 419 minutes. No pulmonary complications occurred postoperatively. At the final follow-up at 3 years 11 months postoperatively, the child had no recurrence of the deformity.Conclusions:The combination of distal anterior multilevel vertebral body fixation with spine-based thoracic growing rods can successfully achieve kyphosis correction in MMC, with the potential to reduce complication rates and facilitate thoracic growth. Further investigation is necessary to prove whether the outcomes and the complication rates are superior to other established techniques.

Cost Comparison of Prenatal Myelomeningocele Closure Versus Postnatal Closure for Both Mother and Child at 1 year of Life

Abstract INTRODUCTION Prenatal myelomeningocele (MMC) closure has been performed in the United States for 2 decades, though economic impact in terms of cost to the hospital when comparing prenatal to postnatal MMC closure is unclear. METHODS A prospective database of patients undergoing prenatal and postnatal MMC closure between 2011 and 2018 with 1 yr follow up was reviewed. Charge data for relevant admissions was converted to a cost estimate using our institution's Medicare hospital-specific cost-to-charge ratio and corrected to the 2018 US dollar. Children, mothers, and mother/child pairs were considered separately. Additional data included length of stay (LOS), gestational age at birth, readmission, and need for ventriculoperitoneal shunt placement. RESULTS Average cost to prenatal MMC closure children was $67,331.49 (median $58,406.71), compared to $89,502.01 (median $49,889.95) for postnatal MMC closure children (P = .28). Cost to prenatal MMC closure mothers was $28,476.12 (median $24,548.29), compared to $5039.27 (median $5,087.30) (P &lt; .001). Cost of care for prenatal MMC closure mother/child pairs was $95,803.11 (median $102,377.75), compared to $94,541.28 (median $55,667.82) (P = .45). Prenatal MMC closure children had shorter gestational age at birth (235.81 d vs 265.77 d, P &lt; .001), fewer readmissions (33.3% vs 72.7%, P &lt; .001), and shunt placement was less common (33.3% vs 90.9%, P &lt; .001). Prenatal MMC closure mothers had longer total LOS (15.92 d vs 4.68 d, P &lt; .001) and more readmissions (18.5% vs 0.0%, P = .06). Total LOS for prenatal MMC closure mother/child pairs was 43.70 d compared to 30.41 d, though not significant (P = .09). CONCLUSION Cost of prenatal versus postnatal MMC closure did not significantly differ from a hospital perspective at 1 yr. When considering the mother alone, prenatal MMC closure was costlier. Future work is needed assessing cost from a patient and societal perspective both at 1 yr and beyond.

A two-phase MMC-LES model for pyrolysing solid particles in a turbulent flame

A two-phase multiple mapping conditioning/large eddy simulation (MMC-LES) model for turbulent flames with solid fuel pyrolysis is derived, numerically implemented and tested. A hybrid approach is used that consists of an Eulerian LES, a stochastic filtered density function method with MMC closure and an inertial Lagrangian fuel particle scheme. A simultaneous interphase heat and mass transfer model with conserved scalar Spalding transfer numbers and localness in mixture fraction space models the pyrolysis of solid fuel particles and volatile gas mixing in the unresolved diffusive layer around each fuel particle. The MMC-LES model is applied to a laboratory-scale, turbulent, pyrolysing coal flame and the predictions are found to be in good overall agreement with the experimental data and comparable to previously reported LES and carrier-phase direct numerical simulations. This paper focuses on the sensitivity of the predictions to numerical parameters and variations in the models for pyrolysis rate and volatile gas composition. Both single first order reaction rate and competing rate pyrolysis models are used and the volatile composition is modelled as both pure methane and a detailed gaseous mixture. The sensitivity of these variations on the predictions of temperature and reactive species mass fractions is marked. Additionally the sensitivity to the presence of envelope flames around individual coal particles is explored and while there are some minor local variations, the steady-state statistics do not vary much.

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.