The impact of a biocellulose-based repair of fetal open spina bifida on the need to untether the cord: is it time to unify techniques for prenatal repair?

ABSTRACT Objective: To report the need for cord untethering after prenatal repair of open spina bifida using a unique biocellulose-based technique performed at a later gestational age. Methods: An observational cohort study was conducted to determine the incidence of tethered cord syndrome. Between May 2013 and May 2022, we performed 172 procedures using the percutaneous fetoscopic approach in fetuses at 26-28 weeks of gestation. After placode dissection, a biocellulose patch was placed to cover the placode, a myofascial flap (when possible) was dissected, and the skin was closed. Owing to death or loss to follow-up, 23 cases were excluded. Cord tethering syndrome was defined as symptoms of medullary stretching, and the infants were evaluated and operated on by local neurosurgeons after an magnetic resonance imaging examination. Infants over 30-month had ambulation and neurodevelopment evaluations (PEDI scale). Results: Among 172 cases operated at a median gestational age of 26.7 weeks and delivered at 33.2 weeks, 149 cases were available for postnatal follow-up, and cord untethering was needed in 4.4% of cases (6/136; excluding 13 cases younger than 12 months). Cerebrospinal fluid diversion and bladder catheterization were needed in 38% and 36% of cases, respectively. Of the 78 cases evaluated at 30 months, 49% were ambulating independently, and 94% had normal social function. Conclusion: The biocellulose-based technique was associated with a low rate of cord tethering, wich may be attributed to the lack of the duramater suture during prenatal repair, the formation of a neoduramater and/or later gestational age of surgery.

Novel multidisciplinary approach to monitor and treat fetuses with gastroschisis using the Svetliza Reducibility Index and the EXIT-like procedure / Nova abordagem multidisciplinar para monitorizar e tratar fetos com gastrosquise utilizando o Svetliza Reducibility Index e o procedimento EXIT-like

ABSTRACT Objective: To describe our initial experience with a novel approach to follow-up and treat gastroschisis in "zero minute" using the EXITlike procedure. Methods: Eleven fetuses with prenatal diagnosis of gastroschisis were evaluated. The Svetliza Reductibility Index was used to prospectively evaluate five cases, and six cases were used as historical controls. The Svetliza Reductibility Index consisted in dividing the real abdominal wall defect diameter by the larger intestinal loop to be fitted in such space. The EXIT-like procedure consists in planned cesarean section, fetal analgesia and return of the herniated viscera to the abdominal cavity before the baby can fill the intestines with air. No general anesthesia or uterine relaxation is needed. Exteriorized viscera reduction is performed while umbilical cord circulation is maintained. Results: Four of the five cases were performed with the EXIT-like procedure. Successful complete closure was achieved in three infants. The other cases were planned deliveries at term and treated by construction of a Silo. The average time to return the viscera in EXIT-like Group was 5.0 minutes, and, in all cases, oximetry was maintained within normal ranges. In the perinatal period, there were significant statistical differences in ventilation days required (p = 0.0169), duration of parenteral nutrition (p=0.0104) and duration of enteral feed (p=0.0294). Conclusion: The Svetliza Reductibility Index and EXIT-like procedure could be new options to follow and treat gastroschisis, with significantly improved neonatal outcome in our unit. Further randomized studies are needed to evaluate this novel approach.

RESUMO Objetivo: Descrever a experiência inicial com a nova técnica cirúrgica EXIT-like para acompanhamento e correção de gastrosquise no "minuto zero". Métodos: Foram avaliados onze fetos com diagnóstico pré-natal de gastrosquise. O Svetliza Reducibility Index foi usado prospectivamente para avaliar cinco casos, e seis foram utilizados como controles. O índice foi calculado dividindo-se o diâmetro do defeito da parede abdominal pela maior alça intestinal que coubesse neste espaço. O procedimento EXIT-like compreendeu cesárea programada, analgesia fetal e redução da víscera herniada para a cavidade abdominal, antes da deglutição de ar pelo recém- nascido. Não são necessários anestesia geral e nem relaxamento uterino. A redução da víscera exteriorizada é realizada enquanto se mantém a circulação do cordão umbilical. Resultados: Quatro casos, dos cinco, foram submetidos ao EXIT-like. A correção foi completa em três casos. Os demais casos foram partos a termo planejados, e a correção do defeito foi feita com Silo. O tempo médio de redução da víscera foi de 5,0 minutos no grupo submetido ao procedimento EXITlike, e a oximetria foi mantida dentro dos valores de variação normal em todos os casos. No período perinatal, foram observadas diferenças estatisticamente significativas no tempo de ventilação mecânica (p=0,0169), duração da nutrição parenteral (p = 0,0104) e da nutrição enteral (p=0,0294). Conclusão: O Svetliza Reducibility Index e o procedimento EXIT-like podem ser novas opções para acompanhar e tratar gastroquise, com desfecho neonatal significativamente melhor em nossa unidade. Novos estudos randomizados são necessários para avaliar esta nova abordagem.

Advances in fetal surgery / Avanços em cirurgia fetal

ABSTRACT This paper discusses the main advances in fetal surgical therapy aiming to inform health care professionals about the state-of-the-art techniques and future challenges in this field. We discuss the necessary steps of technical evolution from the initial open fetal surgery approach until the development of minimally invasive techniques of fetal endoscopic surgery (fetoscopy).

RESUMO São discutidos os principais avanços na terapia cirúrgica do feto, tendo como objetivo informar profissionais da área da saúde sobre qual o estado atual da arte e quais seus desafios futuros. São debatidos os passos que foram necessários para a evolução da técnica inicial, quando a cirurgia fetal era realizada a céu aberto, até o desenvolvimento de técnicas minimamente invasivas, de cirurgia endoscópica fetal (fetoscopia).

Fetoscopy for meningomyelocele repair: past, present and future / Cirurgia fetal endoscópica para correção de mielomeningocele: passado, presente e futuro

ABSTRACT Meningomyelocele is a malformation with high prevalence, and one of its main comorbidities is Arnold-Chiari malformation type II. The intrauterine repair of this defect has been studied to reduce the progressive spinal cord damage during gestation. The purpose of the present review was to describe the evolution of fetal surgery for meningomyelocele repair. Searches on PubMed database were conducted including articles published in the last 10 years. Twenty-seven articles were selected, 16 experimental studies and 11 studies in humans. A recent study demonstrated that the fetal correction results in better prognosis of neurological and psychomotor development, but open surgery, which has being used widely, has considerable maternal risks. Studies in animal and human models show that the endoscopic approach is feasible and leads to lower maternal morbidity rates. Two endoscopic techniques are currently under assessment - one in Germany and another in Brazil, and we believe that the endoscopic approach will be the future technique for prenatal repair of this defect.

RESUMO A meningomielocele é uma malformação de alta incidência e, dentre suas principais comorbidades, está a malformação de Arnold-Chiari tipo II. A fim de reduzir os danos progressivos durante a gestação, tanto a nível medular, quanto sobre a fossa posterior, a correção intrauterina desse defeito vem sendo estudada. A presente revisão teve por objetivo descrever a evolução da cirurgia fetal para a correção da meningomielocele. Foi realizada uma pesquisa na base de dados PubMed, incluindo artigos publicados nos últimos 10 anos. Foram selecionados 27 artigos, sendo 16 de estudos experimentais e 11 sobre pesquisa em humanos. Um estudo recente demonstrou que a correção pré-natal resulta em melhor prognóstico neuropsicomotor, porém a abordagem a céu aberto, que vem sendo amplamente utilizada, possui um risco materno considerável. Estudos, tanto em modelo animal, quanto em humanos, mostram que a abordagem endoscópica é factível e apresenta menor morbidade materna. No momento, duas técnicas de abordagem endoscópica estão sendo estudadas, uma na Alemanha, e outra no Brasil, e acreditamos que a via endoscópica será o futuro da correção pré-natal desse defeito.