Development of a simulator for training of fetoscopic myelomeningocele surgery.

OBJECTIVE: To develop a realistic simulation model for laparotomy-assisted fetoscopic spina bifida aperta (SBa) surgery, to be used for training purposes and preoperative planning. METHODS: The predefined general requirement was a realistic model of an exteriorized uterus, allowing all neurosurgical steps of the intervention. The uterus was modelled using ultrasound and MRI images of a 25 weeks' gravid uterus, consisting of flexible polyurethane foam coated with pigmented silicone. The fetal model, contained an opening on the dorsal side for a customizable spinal insert with all the aspects of a SBa, including a cele, placode, and myofascial and skin layer. The model was assessed in a series of validation experiments. RESULTS: Production costs are low, uterus and fetus are reusable. Placental localization and the level and size of the spinal defect are adjustable, enabling case-specific adaptations. All aspects of the simulator were scored close to realistic or higher for both appearance and functional capacities. CONCLUSIONS: This innovative model provides an excellent training opportunity for centers that are starting a fetoscopic SBa repair program. It is the first simulation model with adjustable spinal defect and placental localisation. Further objective validation is required, but the potential for using this model in preoperative planning is promising.

Neurosurgeons' opinions on the prenatal management of myelomeningocele.

OBJECTIVE: Improvements in imaging and surgical technological innovations have led to the increasing implementation of fetal surgical techniques. Open fetal surgery has demonstrated more favorable clinical outcomes in children born with open myelomeningocele (MMC) than those following postnatal repair. However, primarily because of maternal risks but also because of fetal risks, fetal surgery for MMC remains controversial. Here, the authors evaluated the contemporary management of MMC in the hope of identifying barriers and facilitators for neurosurgeons in providing fetal surgery for MMC. METHODS: An online survey was emailed to members of the Congress of Neurological Surgeons (CNS) and the International Society for Pediatric Neurosurgery (ISPN) in March 2019. The survey focused on 1) characteristics of the respondents, 2) the practice of counseling on and managing prenatally diagnosed MMC, and 3) barriers, facilitators, and expectations of fetal surgery for MMC. Reminders were sent to improve the response rate. RESULTS: A total of 446 respondents filled out the survey, most (59.2%) of whom specialized in pediatric neurosurgery. The respondents repaired an average of 9.6 MMC defects per year, regardless of technique. Regardless of the departments in which respondents were employed, 91.0% provided postnatal repair of MMC, 13.0% open fetal repair, and 4.9% fetoscopic repair. According to the surgeons, the most important objections to performing open fetal surgery were a lack of cases available to become proficient in the technique (33.8%), the risk of maternal complications (23.6%), and concern for fetal complications (15.2%). The most important facilitators according to advocates of prenatal closure are a decreased rate of shunt dependency (37.8%), a decreased rate of hindbrain herniation (27.0%), and an improved rate of motor function (18.9%). Of the respondents, only 16.9% agreed that open fetal surgery should be the standard of care. CONCLUSIONS: The survey results showed diversity in the management of patients with MMC. In addition, significant diversity remains regarding fetal surgery for MMC closure. Despite the apparent benefits of open fetal surgery in selected pregnancies, only a minority of centers and providers offer this technique. As a more technically demanding technique that requires multidisciplinary effort with less well-established long-term outcomes, fetoscopic surgery may face similar limited implementation, although the surgery may pose fewer maternal risks than open fetal surgery. Centralization of prenatal treatment to tertiary care referral centers, as well as the use of sophisticated training models, may help to augment the most commonly cited objection to the implementation of prenatal closure, which is the overall limited caseload.

Contemporary management and outcome of myelomeningocele: the Rotterdam experience.

OBJECTIVE: Myelomeningocele (MMC) is the most common form of spina bifida, with a lifelong impact on the quality of life for infants born with this condition. In recent decades, fetal surgery has evolved from an experimental therapy to standard of care for many centers in the world. In this study, the authors aimed to provide an overview of the current management and outcomes for infants with MMC managed at their institution. This then provides a center-specific historical cohort for comparison with future antenatal-treated MMC cases. METHODS: This is a retrospective, single-institution cohort study including all consecutive MMC cases between January 1, 2000, and June 1, 2018, at Erasmus MC. Outcome data included closure of the defect (location, timing, and surgical parameters), hydrocephalus management, Chiari malformation type II (CMTII) management, incidence of spinal cord tethering and outcome, motor outcomes, and continence. RESULTS: A total of 93 patients were included with predominantly lumbosacral lesions. Two patients died during follow-up. Hydrocephalus was present in 84%, with a 71% ventriculoperitoneal shunt reoperation rate. Surgery was performed in 12% for a tethered spinal cord at a mean age of 8 years. Decompression surgery was performed in 3 patients for CMTII. Special education in 63% was significantly associated with hydrocephalus (p < 0.015). Nineteen percent of patients were able to walk independently, and 47% were nonambulators. Social continence for urine was obtained in 75% of patients, 4% had fecal incontinence. CONCLUSIONS: This study provides an overview of current MMC outcomes at the authors' center and will serve as a historical cohort for comparison with future fetal surgery cases operated on at the center in the coming years. Apart from a relatively low surgical untethering rate, the authors' outcome data are comparable to those in the literature. Hydrocephalus is highly prevalent in postnatally treated MMC patients; in this study as in much of the literature, hydrocephalus is correlated with a low cognitive function. Fetal surgery for MMC halves the need for shunt treatment in a select group of MMC pregnancies, constituting a major indication for us to undergo the transition to a fetal surgery center. The fetal benefits of open antenatal surgery for MMC are well established, yet long-term data on especially tethered spinal cord are eagerly awaited.

Papilledema in patients with Apert, Crouzon, and Pfeiffer syndrome: prevalence, efficacy of treatment, and risk factors.

Patients with syndromic craniosynostosis are at risk for elevated intracranial pressure because of various physiologic and anatomic abnormalities. The aims of this study were to determine the prevalence of papilledema in syndromic craniosynostosis, to evaluate the results of the treatment, and to examine the risk factors. This is a retrospective study on 84 patients with Apert, Crouzon, or Pfeiffer syndrome. Papilledema was defined as blurring of the margins of the optic disk. The association between clinical symptoms, beaten-copper pattern on skull radiograph, ventricular dilatation on computed tomography scan, and papilledema was assessed. Papilledema was present in 51% of the patients. No relation between specific clinical symptoms and papilledema was found. The significant associations were complex craniosynostosis, exorbitism, and ventricular dilatation. The prevalence of papilledema in patients with Apert, Crouzon, or Pfeiffer syndrome is high, not only before cranial decompression but also after vault expansion. Annual fundoscopy is recommended to screen for papilledema. We consider that early decompressive surgery (within the first year of age) prevents the development of papilledema and, most likely, elevated intracranial pressure.

Condition variables in children with craniofacial anomalies: a descriptive study.

The objective of the study is to describe the prevalence of a number of condition variables and their interrelations in children with craniofacial anomalies (CFAs). The participants were 217 children with CFAs (125 boys and 92 girls), aged 5 to 16 years. The medical files and brain imaging provided information on most condition variables except for the variable phenotypical expression, on which information was obtained in a rating experiment. Brain anomalies were present in 77 subjects (36%), absent in 79 subjects (36%), and undefined in 61 subjects (28%). Craniosynostosis occurred in 160 children (74%), a syndromic diagnosis in 108 (50%), and clinical hypertelorism in 72 (33%). The mean phenotypical expression score was 4.8 (SD = 2.1), the mean number of hospitalizations was 6.2 (SD = 5.6), and mean age at craniotomy was 10.9 months (SD = 9.3). Many of the condition variables were significantly interrelated. Brain anomalies occur frequently (36%) in syndromic and nonsyndromic forms of CFAs. The most salient condition variables are the presence of brain anomalies, a syndromic diagnosis, clinical hypertelorism, a severe phenotypical expression, and female gender. Individuals presenting with one or more of these condition variables probably form the most severely affected group and require more treatment.