Twenty years' experience with myelomeningocele management at a single institution: lessons learned

Current status and challenges of neurosurgical procedures for patients with myelomeningocele in real-world Japan

BACKGROUND

Little is known about the real-world status of neurosurgical treatment of myelomeningocele patients.

OBJECTIVE

To investigate the real-world status of neurosurgical treatment of myelomeningocele patients, medical claims data provided by the Japan Medical Data Center (JMDC) were analyzed.

METHODS

The health claims data of 556 patients with myelomeningoceles from January 2005 to March 2020 were examined. The number of neurosurgical procedures, including myelomeningocele repair, tethered cord release, cerebrospinal fluid (CSF) shunt, CSF drainage, and endoscopic third ventriculostomy (ETV), was determined.

RESULTS

A total of 313 neurosurgical procedures were performed for 135 patients in 74 institutions during the study period. The shunt survival rate was most affected by shunts that were revised when the patient was less than 1 year old, which had a significantly lower survival rate than all of the initial shunts performed when the patient was less than on1 year old; the 1-year shunt survival rate was 35 vs 64% (P = 0.0102). The survival rate was significantly lower in patients younger than 1 year who had CSF drainage before shunting compared to those younger than 1 year who did not have CSF drainage before shunting; the 1-year shunt survival rate was 27 vs 59% (P = 0.0196), and 81% of patients remained free of tethered cord release 10 years later.

CONCLUSIONS

In this study, a revised shunt of less than 1 year of age and CSF drainage before shunting were the factors that lowered the shunt survival rate in the real world for CSF shunts for hydrocephalus associated with myelomeningocele.

Myelomeningocele: the evolution of care over the last 50 years

PURPOSE

Myelomeningocele (MMC) is one of the representative anomalies in the field of pediatric neurosurgery. During the 50 years of ISPN history, MMC had a tremendous changes in its incidence, clinical management and outcome with advanced understanding of its pathogenesis. We reviewed the changes in MMC during the period.

METHODS

We reviewed the literature review and collected our experiences.

RESULTS

During the 50 years, major changes happened in many aspects of MMC including incidence, pathoembryogenesis, folate deficiency, prevention, prenatal diagnosis, mode of delivery, treatment policy with ethical considerations, clinical treatment including fetal surgery, latex allergy, retethering, management outcome, multidisciplinary team approach, and socioeconomic and family issues.

CONCLUSIONS

There was a great advance in the management and research of MMC during the 50 years. It is a monumental achievement of pediatric neurosurgeons and colleagues of the related fields.

Effect of preoperative low-normal cervical length on perinatal outcome after laparotomy-assisted fetoscopic spina bifida repair

OBJECTIVE

To determine if preoperative cervical length in the low-normal range increases the risk of adverse perinatal outcome in patients undergoing fetoscopic spina bifida repair.

METHODS

This was a retrospective cohort study of patients who underwent fetal spina bifida repair between September 2014 and May 2022 at a single center. Cervical length was measured on transvaginal ultrasound during the week before surgery. Eligibility for laparotomy-assisted fetoscopic spina bifida repair was as per the criteria of the Management of Myelomeningocele Study, although maternal body mass index (BMI) up to 40 kg/m² was allowed. Laparotomy-assisted fetoscopic spina bifida repair was performed, with carbon dioxide insufflation via two 12-French ports in the exteriorized uterus. All patients received the same peri- and postoperative tocolysis regimen, including magnesium sulfate, nifedipine and indomethacin. Postoperative follow-up ultrasound scans were performed either weekly (< 32 weeks' gestation) or twice a week (≥ 32 weeks). Perinatal outcome was compared between patients with a preoperative cervical length of 25-30 mm vs those with a cervical length > 30 mm. Logistic regression analyses and generalized linear mixed regression analyses were used to predict delivery at less than 30, 34 and 37 weeks' gestation.

RESULTS

The study included 99 patients with a preoperative cervical length > 30 mm and 12 patients with a cervix 25-30 mm in length. One further case which underwent spina bifida repair was excluded because cervical length was measured > 1 week before surgery. No differences in maternal demographics, gestational age (GA) at surgery, duration of surgery or duration of carbon dioxide uterine insufflation were observed between groups. Cases with low-normal cervical length had an earlier GA at delivery (median (range), 35.2 (25.1-39.7) weeks vs 38.2 (26.0-40.9) weeks; P = 0.01), higher rates of delivery at < 34 weeks (41.7% vs 10.2%; P = 0.01) and < 30 weeks (25.0% vs 1.0%; P < 0.01) and a higher rate of preterm prelabor rupture of membranes (PPROM) (58.3% vs 26.3%; P = 0.04) at an earlier GA (mean ± SD, 29.3 ± 4.0 weeks vs 33.0 ± 2.4 weeks; P = 0.05) compared to those with a normal cervical length. Neonates of cases with low-normal cervical length had a longer stay in the neonatal intensive care unit (20 (7-162) days vs 9 (3-253) days; P = 0.02) and higher rates of respiratory distress syndrome (50.0% vs 14.4%; P < 0.01), sepsis (16.7% vs 1.0%; P = 0.03), necrotizing enterocolitis (16.7% vs 0%; P = 0.01) and retinopathy (33.3% vs 1.0%; P < 0.01). There was an association between preoperative cervical length and risk of delivery at < 30 weeks which was significant only for patients with a maternal BMI < 25 kg/m² (odds ratio, 0.37 (95% CI, 0.07-0.81); P = 0.02).

CONCLUSIONS

Low-normal cervical length (25-30 mm) as measured before in-utero laparotomy-assisted fetoscopic spina bifida repair may increase the risk of adverse perinatal outcomes, including PPROM and preterm birth, leading to higher rates of neonatal complications. These data warrant further research and are of critical relevance for clinical teams considering the eligibility of patients for in-utero spina bifida repair. Based on this evidence, patients with a low-normal cervical length should be aware of their increased risk for adverse perinatal outcome. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Association between ambulatory skills and diffusion tensor imaging of corpus callosal white matter in infants with spina bifida

OBJECTIVES

To assess brain white matter using diffusion tensor imaging (DTI) at 1 year of age in infants diagnosed with open neural tube defect (ONTD) and explore the association of DTI parameters with ambulatory skills at 30 months of age.

METHODS

Magnetic resonance imaging (MRI) was performed at an average of 12 months of age and included an echo planar axial DTI sequence with diffusion gradients along 20 non-collinear directions. TORTOISE software was used to correct DTI raw data for motion artifacts, and DtiStudio, DiffeoMap and RoiEditor were used for further postprocessing. DTI data were analyzed in terms of fractional anisotropy (FA), trace, radial diffusivity and axial diffusivity. These parameters reflect the integrity and maturation of white-matter motor pathways. At 30 months of age, ambulation status was evaluated by a developmental pediatrician, and infants were classified as ambulatory if they were able to walk independently with or without orthoses or as non-ambulatory if they could not. Linear mixed-effects method was used to examine the association between study outcomes and study group. Possible confounders were sought, and analyses were adjusted for age at MRI scan and ventricular size by including them in the regression model as covariates.

RESULTS

Twenty patients with ONTD were included in this study, including three cases that underwent postnatal repair and 17 cases that underwent prenatal repair. There were five ambulatory and 15 non-ambulatory infants evaluated at a mean age of 31.5 ± 5.7 months. MRI was performed at 50.3 (2-132.4) weeks postpartum. When DTI analysis results were compared between ambulatory and non-ambulatory infants, significant differences were observed in the corpus callosum (CC). Compared with non-ambulatory infants, ambulatory infants had increased FA in the splenium (0.62 (0.48-0.75) vs 0.41 (0.34-0.49); P = 0.01, adjusted P = 0.02), genu (0.64 (0.47-0.80) vs 0.47 (0.35-0.61); P = 0.03, adjusted P = 0.004) and body (0.55 (0.45-0.65) vs 0.40 (0.35-0.46), P = 0.01, adjusted P = 0.01). Reduced trace was observed in the CC of ambulatory children at the level of the splenium (0.0027 (0.0018-0.0037) vs 0.0039 (0.0034-0.0044) mm² /s; P = 0.04, adjusted P = 0.03) and genu (0.0029 (0.0020-0.0038) vs 0.0039 (0.0033-0.0045) mm² /s; P = 0.04, adjusted P = 0.01). In addition, radial diffusivity was reduced in the CC of the ambulatory children at the level of the splenium (0.00057 (0.00025-0.00089) vs 0.0010 (0.00084-0.00120) mm² /s; P = 0.02, adjusted P = 0.02) and the genu (0.00058 (0.00028-0.00088) vs 0.0010 (0.00085-0.00118) mm² /s; P = 0.02, adjusted P = 0.02). There were no differences in axial diffusivity between ambulatory and non-ambulatory children.

CONCLUSION

This study demonstrates a significant association between white matter integrity of connecting fibers of the corpus callosum, as assessed by DTI, and ambulatory skills at 30 months of age in infants with ONTD. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Myelomeningocele as an anomaly of secondary neurulation

PURPOSE

Myelomeningocele (MMC) is the representative entity of open neural tube defects resulting from an error during primary neurulation. However, cases of MMC in the region of the secondary neural tube (below the junction of S1 and S2 vertebrae) are sometimes encountered. We aimed to analyze the clinical features of atypical "low-lying" MMC in comparison to the typical MMC and suggest possible pathoembryogenesis.

METHODS

From 1986 to 2020, 95 MMC patients were treated in our institute. A retrospective review of the radiological and clinical information was performed. We defined "low-lying" MMCs as those with fascia or lamina defects below the S1-2 interspinous ligament.

RESULTS

Thirty-one out of the 95 MMC patients were identified as having low-lying MMC. The percentage of low-lying MMC within the entire MMC group increased dramatically (19% from 1990 to 1999 and 48% from 2000 to 2020). Thirty-nine percent of the low-lying MMCs were associated with hydrocephalus, and 36% showed the Chiari malformation. Clean intermittent catheterization was being performed by 52% of the patients and 46% had a motor weakness. The proportions of hydrocephalus, neurological symptoms, and the number of related procedures in the low-lying MMC were substantially lower than the typical MMC in our cohort and the literature.

CONCLUSIONS

We present cases of atypical MMC occurring in the region of secondary neurulation. These cases provide clues that secondary neurulation may lead to open neural defects. Future experiments with animal models supporting what we have seen in the clinics will greatly enhance the understanding of the developmental process of neurulation and the corresponding anomalies.

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

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

Tethered spinal cord among individuals with myelomeningocele: an analysis of the National Spina Bifida Patient Registry

OBJECTIVE

The aims of this study were to review the National Spina Bifida Patient Registry (NSBPR) data set to study the rates of tethered spinal cord release (TCR) among patients with myelomeningocele and variability between centers, to compare TCR rates between males and females, and to study the relationships between TCR rates and other condition-specific characteristics.

METHODS

The NSBPR registry was queried to identify all patients with myelomeningocele. TCR rates were calculated over time using survival analyses; rates between centers and between males and females were compared. Cox proportional hazards models were constructed to identify relationships between TCR rates and sex, functional lesion level, ambulation status, treated hydrocephalus, and prior Chiari decompression.

RESULTS

Of 6339 patients with information about their operations, 1366 (21.5%) underwent TCR, with significant variability between centers. The majority (75.8%) underwent a single TCR. The annual TCR rate was linear between birth and 13 years (1.8%/year) but declined sharply from 14 to 21 years (0.7%/year). There was no period of time at which the TCR rate accelerated. There were no significant differences in TCR rates between males and females. TCR rate was not related to functional lesion level but was lower among nonambulators compared with community ambulators (p = 0.005) and among those with treated hydrocephalus (HR 0.30, p < 0.001), and higher among those having prior Chiari decompression (HR 1.71, p < 0.001).

CONCLUSIONS

These results extend the results of prior single-institution studies, demonstrate significant treatment variability between institutions, and challenge the traditional concept that tethering is related to spinal cord stretching due to spinal growth.

Shunt infection and malfunction in patients with myelomeningocele

OBJECTIVE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

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

PURPOSE

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.

METHODS

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.

RESULTS

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 ± 2.7 days 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).

CONCLUSIONS

In neonates who undergo MMC closure in the first 48 h 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.

Evaluation of Neurological Examination, SEP Results, MRI Results, and Lesion Levels in Patients Who Had Been Operated for Myelomeningocele

Objective:

Myelomeningocele is the most severe and the most frequent form of spina bifida. Most of the myelomeningocele patients undergo operations in new-born age. In terms of life quality and rehabilitation, follow-up’s of these patients in the growth and development period after the operation is critical. In our study, our aim is to emphasize the correlation of SEP results with MRI results and clinical features of the myelomeningocele patients.

Materials and Methods:

In our study, we included 36 patients who had undergone myelomeningocele operation and have been followed-up in Istanbul Bilim University Florence Nightingale Hospital, Spina Bifida Research and Treatment Centre. Posterior tibial nerve SEP was performed on each patient and neurological examinations were done in the same session. Results were compared with clinical functional lesion levels, levels of fusion defect and ambulation levels. In order to evaluate SEP results, we used age-related reference values from Boor et al.’s study in 2008. Patients were grouped as normal, unilaterally prolonged, bilaterally prolonged, unilaterally lost, and bilaterally lost.

Results:

The correlations of posterior tibial nerve SEP results were significant with ambulation levels (r = 0.428, P < 0.01), clinical functional lesion levels (r = 0.477, P < 0.01) and fusion defect levels (r = −0.528 P < 0.05). The lumbar SEP results were only significantly correlated with functional lesion levels (r = 0.443 P < 0.05).

Conclusions:

Radiological studies are insufficient when evaluating the functionality of the central nervous system. To fully evaluate the functionality and watch the neurological development with accuracy, especially in operated patients, electrophysiological studies should be an indispensable part of myelomeningocele follow-ups.

Shunt timing in meningomyelocele and clinical results: analysis of 80 cases

PURPOSE

Meningomyelocele is a serious pathology that requires immediate surgical treatment. Its management is difficult due to accompanying other pathologies and hydrocephalus. Shunt timing is still controversial. Therefore, this study retrospectively assessed 80 patients in order to improve the shunt timing and management of patients with meningomyelocele.

METHODS

A total of 80 patients were followed up for 18-48 (average, 23) months. Patients were analyzed for the following variables: delivery method and time, head circumference monitoring, shunt timing, complication rates of patients who underwent shunting, during the early or follow-up period, accompanying pathologies, size, and localization of lesion.

RESULTS

Patients including 46 males and 34 females have been operated. In 40% of patients, the accompanying pathology was determined. Approximately 85% of patients had hydrocephalus, and a ventriculoperitoneal shunt was placed on 36 symptomatic and 22 patients with hydrocephalus that developed during the follow-up. Differences in shunt-related and general complications were not significant between patients who underwent shunt placement during the same session and patients who underwent shunt placement during the follow-up. However, the incidence of cerebrospinal fluid fistula formation from the wound in patients who underwent shunt placement during the same session was significantly lower than those who underwent shunt placement during follow-up.

CONCLUSIONS

Immediate surgery (within the first 48 h) provides positive results, which is consistent with the existing literature. According to the logistic regression analysis, the placement of the meningomyelocele sac in the lumbosacral region is decisive in shunt insertion. Placing the shunt in the same session for patients with hydrocephalus and later for patients who developed hydrocephalus during the follow-up is recommended as a favorable treatment.

Comparison of Follow-Up Length-Matched Single-Center Myelomeningocele Postnatal Closure Cohort to the Management of Myelomeningocele Study (MOMS) Trial Results

OBJECTIVE

We sought to compare our large single-institution cohort of postnatal myelomeningocele closure to the 2 arms of the Management of Myelomeningocele Study (MOMS) trial at the designated trial time points, as well as assess outcomes at long-term follow-up among our postnatal cohort.

METHODS

A single-institutional retrospective review of myelomeningocele cases presenting from 1995 to 2015 at Children's Hospital of Pittsburgh was performed. We compared outcomes at 12 and 30 months to both arms of the MOMS trial and compared our cohort's outcomes at those designated time points to our long-term outcomes. Univariate statistical analysis was performed as appropriate.

RESULTS

One-hundred sixty-three patients were included in this study. All patients had at least 2-year follow-up, with a mean follow-up of 10 years (range 2-20 years). There was no difference in the overall distribution of anatomic level of defect. Compared to our cohort, the prenatal cohort had a higher rate of tethering at 12 months of age, 8 versus 1.8%. Conversely, the Chiari II decompression rate was higher in our cohort (10.4 vs. 1.0%). At 30 months, the prenatal cohort had a higher rate of independent ambulation, but our cohort demonstrated the highest rate of ambulation with or without assistive devices among the 3 groups. When comparing our cohort at these early time points to our long-term follow-up data, our cohort's ambulatory function decreased from 84 to 66%, and the rate of detethering surgery increased almost 10-fold.

CONCLUSIONS

This study demonstrated that overall ambulation and anatomic-functional level were significantly better among our large postnatal cohort, as well as having significantly fewer complications to both fetus and mother, when compared to the postnatal cohort of the MOMS trial. Our finding that ambulatory ability declined significantly with age in this patient population is worrisome for the long-term outcomes of the MOMS cohorts, especially given the high rates of cord tethering at early ages within the prenatal cohort. These findings suggest that the perceived benefits of prenatal closure over postnatal closure may not be as substantial as presented in the original trial, with the durability of results still remaining a concern.

Endoscopic third ventriculostomy in patients with myelomeningocele after shunt failure

PURPOSE

Myelomeningocele (MMC) is the most frequent form of spina bifida. Moreover, 90% of patients with MMC have hydrocephalus and require shunt placement. However, shunt failure management in such patients typically involves several shunt revisions, increasing the risk for morbidity and mortality. In this study, we report our experience with endoscopic third ventriculostomy (ETV) in MMC patients with shunts in a Brazilian institution.

METHODS

Patients with MMC who presented with shunt failure and underwent ETV alone between January 1996 and December 2016 were included in this study. Patients who had undergone endoscopic choroid plexus cauterization (CPC) or had non-shunted MMC hydrocephalus were excluded. Various data related to the ETV procedure were collected for each patient, including features, operative characteristics, complications, and ETV success. The follow-up period for the patients was 6-12 months. ETV success scores (ETVSSs) were calculated retrospectively for each patient to compare the predicted success of the procedure with the actual success at 6 months after ETV.

RESULTS

Forty-three MMC patients with shunt failure were included in this study. Of them, 16 (37.2%) had a previous central nervous system (CNS) infection and 4 (9.3%) had complications. Two neuroendoscopies were interrupted, one because of anatomic impossibility due to thickening of the interthalamic adhesion, obliterating the floor of the third ventricle, and another because of intraoperative hemorrhage. One patient developed hyponatremia during the postoperative period, whereas another developed reversible paresis of the oculomotor nerve. The ETVSS predicted a success rate of 49.6% compared with the actual ETV success rate of 53.48% (23 patients) at 6 months. At 12 months, the actual success rate was 41.9% (18 patients). All patients survived the procedure.

CONCLUSION

Our findings indicate that ETV is an effective procedure for managing MMC-related hydrocephalus after shunt failure. The expertise of the neurosurgeon in neuroendoscopy procedures is often the deciding factor when choosing a management option. Accordingly, less experienced neurosurgeons should be warned of the risks of this procedure.

Prenatal predictors of motor function in children with open spina bifida: a retrospective cohort study

OBJECTIVE

To identify predictors for intact motor function (MF) at birth and at 12 months of life in babies with prenatally versus postnatally repaired open spina bifida (OSB).

DESIGN

Retrospective cohort study.

SETTING

Texas Children's Hospital, 2011-2018.

POPULATION

Patients who underwent either prenatal or postnatal OSB repair.

METHODS

Prenatal MF of the lower extremities was evaluated by ultrasound following a metameric distribution at the time of diagnosis (US1), 6 weeks postoperatively (or 6 weeks after initial evaluation in postnatally repaired cases) (US2) and at the last ultrasound before delivery (US3). At birth and at 12 months, MF was assessed clinically. Intact MF (S1) was defined as the observation of plantar flexion of the ankle. Results from logistic regression analysis are expressed as odds ratios (95% confidence intervals, P values).

RESULTS

A total of 127 patients were included: 93 with prenatal repair (51 fetoscopic; 42 open hysterotomy repair) and 34 with postnatal repair. In the prenatal repair group, predictors for intact MF at birth and at 12 months included: absence of clubfeet (OR 11.3, 95% CI 3.2-39.1, P < 0.01; OR 10.8 95% CI 2.4-47.6, P < 0.01); intact MF at US1 (OR 19.7, 95% CI 5.0-76.9, P < 0.01; OR 8.7, 95% CI 2.0-38.7, P < 0.01); intact MF at US2 (OR 22, 95% CI 6.5-74.2, P < 0.01; OR 13.5, 95% 3.0-61.4, P < 0.01); intact MF at US3 (OR 13.7, 95% CI 3.4-55.9, P < 0.01; OR 12.6, 95% CI 2.5-64.3, P < 0.01); and having a flat lesion (OR 11.2, 95% CI 2.4-51.1, P < 0.01; OR 4.1, 95% CI 1.1-16.5, P = 0.04). In the postnatal repair group, the only predictor of intact MF at 12 months was having intact MF at birth (OR 15.2, 95% CI 2.0-113.3, P = 0.03).

CONCLUSIONS

The detection of intact MF in utero from mid-gestation to delivery predicts intact MF at birth and at 12 months in babies who undergo prenatal OSB repair.

TWEETABLE ABSTRACT

Detection of intact motor function in utero predicts intact motor function at birth and at 1 year in fetuses who undergo prenatal OSB repair.

The Stimulation of Neurogenesis Improves the Cognitive Status of Aging Rats Subjected to Gestational and Perinatal Deficiency of B9-12 Vitamins

A deficiency in B-vitamins is known to lead to persistent developmental defects in various organs during early life. The nervous system is particularly affected with functional retardation in infants and young adults. In addition, even if in some cases no damage appears evident in the beginning of life, correlations have been shown between B-vitamin metabolism and neurodegenerative diseases. However, despite the usual treatment based on B-vitamin injections, the neurological outcomes remain poorly rescued in the majority of cases, compared with physiological functions. In this study, we explored whether a neonatal stimulation of neurogenesis could compensate atrophy of specific brain areas such as the hippocampus, in the case of B-vitamin deficiency. Using a physiological mild transient hypoxia within the first 24 h after birth, rat-pups, submitted or not to neonatal B-vitamin deficiency, were followed until 330-days-of-age for their cognitive capacities and their hippocampus status. Our results showed a gender effect since females were more affected than males by the deficiency, showing a persistent low body weight and poor cognitive performance to exit a maze. Nevertheless, the neonatal stimulation of neurogenesis with hypoxia rescued the maze performance during adulthood without modifying physiological markers, such as body weight and circulating homocysteine. Our findings were reinforced by an increase of several markers at 330-days-of-age in hypoxic animals, such as Ammon’s Horn 1hippocampus (CA1) thickness and the expression of key actors of synaptic dynamic, such as the NMDA-receptor-1 (NMDAR1) and the post-synaptic-density-95 (PSD-95). We have not focused our conclusion on the neonatal hypoxia as a putative treatment, but we have discussed that, in the case of neurologic retardation associated with a reduced B-vitamin status, stimulation of the latent neurogenesis in infants could ameliorate their quality of life during their lifespan.

Reviewing the prognostic factors in myelomeningocele

OBJECTIVE

The goal of this study was to analyze the factors that have an impact on morbidity and mortality in patients with myelomeningocele (MMC).

METHODS

A retrospective cohort study was conducted to analyze factors associated with MMC that influence the morbidity and mortality of the disease. Data were collected from medical records of children who underwent the primary repair of MMC at the Fernandes Figueira Institute-Oswaldo Cruz Foundation (IFF-Fiocruz) between January 1995 and January 2015, with a minimum follow-up of 1 year. The following variables were analyzed: demographic characteristics (gestational age, sex, and birth weight); clinical features (head circumference at birth, anatomical and functional levels of MMC, hydrocephalus, symptomatic Chiari malformation type II, neurogenic bladder, and urinary tract infection [UTI]); and surgical details such as timing of repair of MMC, age at first shunt placement, shunt surgery modality (elective or emergency), concurrent surgery (correction of MMC and shunt insertion in the same surgical procedure), incidence and cause of shunt dysfunction, use of external ventricular drain, transfontanelle puncture, surgical wound complications prior to shunting, and endoscopic treatment of hydrocephalus.

RESULTS

A total of 231 patients with MMC were included in the analysis. Patients were followed for periods ranging from 1 to 20 years, with a mean of 6.9 years. The frequency of shunt placement was observed mainly among patients with MMC at the highest spinal levels (p < 0.01). The main causes of morbidity and mortality in patients with MMC were shunt failures, diagnosed in 91 of 193 cases (47.2%) of hydrocephalus, and repeated UTIs, in 129 of 231 cases (55.8%) of MMC; these were the main causes of hospitalization and death. Head circumference ≥ 38 cm at birth was found to be a significant risk factor for shunt revision (p < 0.001; 95% CI 1.092-1.354). Also, the lumbar functional level of MMC was associated with less revision than upper levels (p < 0.014; 95% CI 0.143-0.805). There was a significant association between recurrent UTI and thoracic functional level.

CONCLUSIONS

Macrocephaly at birth and higher levels of the defect have an impact on worse outcome and, therefore, are a challenge to the daily practice of pediatric neurosurgery.

Thirty-day medical and surgical readmission following prenatal versus postnatal myelomeningocele repair

OBJECTIVE

Hospital readmission is an important quality metric that has not been evaluated in prenatal versus postnatal myelomeningocele (MMC) repair. This study compares hospital readmission outcomes between these two groups as well as their etiologies.

METHODS

The medical records of patients who had undergone MMC repair in the period from 2011 to 2017 at a single academic medical center were retrospectively reviewed. Collected clinical data included surgery and defect details, neonatal intensive care unit (NICU) stay, and any readmissions or surgical procedures up to 1 year after surgery. Patient and defect characteristics, readmission outcomes at 30 and 60 days and 1 year after discharge from the NICU, and cerebrospinal fluid (CSF) diversion surgery rates were analyzed with the two-tailed t-test and/or k-sample test on the equality of medians.

RESULTS

A total of 24 prenatal and 34 postnatal MMC repairs were completed during the study period. Prenatally repaired patients were born more prematurely (p < 0.001) and with lower birth weights (p < 0.001), although the NICU stay was similar between the two groups (p = 0.59). Fewer prenatally repaired patients were readmitted at 30 days (p = 0.005), 90 days (p = 0.004), and 1 year (p = 0.007) than the postnatal repair group. Hydrocephalus was the most common readmission etiology, and 29% of prenatal repair patients required CSF diversion at 1 year versus 81% of the postnatal repair group (p < 0.01). Prenatal patients who required CSF diversion had a higher body weight (p = 0.02) and an older age (p = 0.01) at the time of CSF diversion surgery than the postnatal group.

CONCLUSIONS

Patients with prenatal MMC repair had fewer hospital readmissions at 30 days, 60 days, and 1 year than the postnatal repair group, despite similar NICU lengths of stay. The prenatal repair group had lower requirements for CSF diversion at 1 year and was older with greater body weights at the time of CSF diversion surgery, compared to those of the postnatal repair group. Future study of hospital quality metrics such as readmissions should be performed to better understand outcomes of these two procedures.

Surgical management of Chiari malformation type II

BACKGROUND

Chiari malformation type II is present in almost all patients with myelomeningocele but usually remains asymptomatic. Symptoms are generally more severe in neonates, who have the worst prognosis. The association symptoms/hydrocephalus is well known, and first treatment usually consists of ensuring adequate ventricular drainage. Craniovertebral decompression may be required in patients who do not improve after drainage. However, mechanisms of symptom development are not yet completely understood, timing and techniques of surgery are not codified, long-term evolution is poorly reported, and there are few paper reporting clinical onset and treatment in older patients.

METHODS

We reviewed our personal series of 42 consecutive symptomatic patients that required surgical treatment. Age at surgery ranged from 1 week to 44 years (mean 6.6 years). Surgical timing strictly depended on clinical conditions: urgent management in the more compromised patients (usually infants) and elective treatment before severe deterioration in patients with less severe conditions. All patients first underwent external ventricular drainage, which resolved the symptomatology in 17 cases (40%). Craniocervical decompression was required by 25 patients (60%) who received no benefit from the ventricular drainage.

RESULTS

Early mortality (2 cases = 4.7%) occurred only in neonates. Clinical improvement was achieved in 37 of 40 survivors (92%). During a follow-up ranging from 2 to 20 years (mean 10.3 years), late mortality consisted of 4 cases (10%), mainly due to cardio-respiratory arrest. Twenty-two patients (55%) required surgery for shunt malfunction and 4 for cord detethering. Six patients (15%) required reoperation owing to symptom recurrence.

CONCLUSION

Early treatment of symptomatic Chiari II malformations may warrant satisfactory results in a significant number of patients, even in neonates. Nevertheless, overall mortality remains relatively high, throughout the patient life. Formal transition programs and adult spina bifida care processes have become crucial.

Bowel perforation after ventriculoperitoneal-shunt placement: case report and review of the literature

Bowel perforation by a peritoneal catheter (BPPC) is a serious complication after ventriculoperitoneal shunting, with high mortality and morbidity rates. This patient presented with scalp ulceration over the shunt valve at the retromastoid region 26 years after shunt placement. During revision, the catheter distal to the valve was divided in the clavicular region. As there was no cerebrospinal fluid drainage, we decided to remove the ventricular catheter and valve. The ulceration was debrided and primarily closed. Distal to the clavicle, the disconnected peritoneal catheter was encased in a fibrous, calcified tunnel. To avoid piecemeal resection with multiple incisions, the catheter was not retrieved. Two years later, the patient presented with an abscess and pus draining from the clavicular wound. Cultures were positive for enteric bacteria. BPPC with retrograde spread of infection was suspected, and abdominal computed tomography confirmed perforation. We removed the disconnected catheter, but the perforation site could not be detected during laparotomy. The patient was treated with intravenous antibiotics and recovered without complications. To minimize complications, abandoned catheters should be avoided. Otherwise, patients unnecessarily have a life-long risk of developing abdominal complications. In patients with abandoned catheters and severe abdominal symptoms, BPPC is an important differential diagnosis.

Use of an abdominal reapproximation anchor system in the closure of large, open myelomeningoceles

Open neural tube defects are complex congenital abnormalities of the nervous system in which nervous tissue is exposed on the patient's back at the time of delivery. These malformations require surgical correction, and although replacement of the neural placode internally is fairly standard, providing skin closure can be very challenging especially in large defects. An abdominal reapproximation anchor (ABRA) device may be of value in attaining skin closure in these large, open myelomeningocele defects in which primary closure cannot be accomplished surgically. In a study period during which 65 patients underwent surgical closure of open myelomeningocele defects, 5 of them underwent ABRA-assisted closure.The average surgical intervention for myelomeningocele repair occurred on day 2.2 of life (range 2-3 days). The average defect size was 37 cm2 (range 16-56 cm2), and the average time to formal closure was 30.8 days (range 8-63 days). One of the patients had natural closure with just ABRA approximation. The remaining 4 patients underwent formal delayed primary closure when the skin edges became approximated. Use of the ABRA system in the closure of a large, open myelomeningocele may be valuable in select patients but requires further follow-up and comparison to identify truly significant differences with traditional techniques.

Growing up with spina bifida: bridging the gaps in the transition of care from childhood to adulthood

Spina bifida is the most common nonchromosomal birth defect, resulting in permanent disability of multiple organ systems, yet compatible with long-term survival. Important advances across various disciplines have now improved survival among the spina bifida population. Although the majority of individuals living with spina bifida are now adults, there are few publications in the neurosurgical literature regarding the care of adults with spina bifida, associated medical conditions, surgical interventions, and long-term complications. The major goals for transitioning adult patients with spina bifida are preservation of function and promotion of independence as well as general overall health. Nevertheless, many gaps exist in our knowledge and understanding of the complex needs of this aging patient population. The goal of this paper was to provide a comprehensive updated review of the literature regarding the challenges and considerations involved in the transitional care to adulthood for patients with spina bifida. Unique to this review, the authors provide a first-hand personal communication and interview with an adult patient with spina bifida that discusses many of these challenges with transition.