Fetal Endoscopic Surgery for Spina Bifida (FESSB)

This study aims to assess the feasibility to perform a fetoscopic prenatal repair of an open neural tube defect, and secondly to assess the maternal, fetal and neonatal outcomes.

Introduction: Spina bifida is a congenital malformation characterized by a failure in neural tube closure. Unprotected fetal neural tissue at the spine level undergoes not only progressive neurodegeneration in spinal cord, but also the impairment in brain development, hindbrain herniation or Chiari II malformation probably due to pressure disturbances resulting from a continuous leakage of cerebrospinal fluid through the defect. The neurological consequences at birth are irreversible and sometimes devastating, including paraplegia, sphincter urinary and fecal incontinence, hydrocephalus, cranial nerve disturbances, respiratory problems and death due to spinal cord injury and brain maldevelopment. Intrauterine fetal open repair of the defect has proved to improve hindbrain herniation and decrease the need of cerebrospinal shunting. Hypothesis: The investigators hypothesize that minimally invasive surgery of spina bifida is feasible and may minimize surgical aggression and obstetrical complications, with similar neonatal and neurological results. Intervention: In this study the investigators propose a fetoscopic skin closure technique. After a maternal laparotomy the uterus is exteriorized, the amniotic cavity is accessed by fetoscopic approach. The placode is dissected from the surrounding tissue and dropped into the opened spinal canal, untethered. Part of the cystic tissue is resected. The edges are then closed to the midline. Follow up: After surgery patients are followed up at the Fetal Medicine Unit every one or two weeks. The mode of delivery is decided according to obstetric criteria. Neonates will be examined at birth, and followed up regularly at least until 30 months. Patients are lifetime followed up by our Multidisciplinary myelomeningocele (MMC) Committee that comprises professionals from the Spina Bifida Unit, Neonatologists, Pediatric Surgeons, Pediatric Urologist, Pediatric Orthopedic Surgeons, Radiologists, Rehabilitation, Pathologists, Pediatric Neurosurgeons, Obstetricians and Fetal Therapists.

Neural Tube Defects, Spina Bifida, Open, Myelomeningocele, Fetal Disease, Hydrocephalus, Chiari Malformation Type 2, Congenital Abnormality, Surgery; Maternal, Uterus or Pelvic Organs, Affecting Fetus

Binary variable (yes/no) describing if the neural tube defect has been successfully closed, (placode dissected and dropped into the open spinal canal, cystic tissue resected and edges closed to the midline), by fetoscopic surgery, and without conversion to open surgery

Binary variable describing if a transfusion of blood derivates is carried out between the time of procedure and discharge

Binary variable describing the presence of a oligohydramnios (deepest pool < 2 cm) without evidence of vaginal amniotic fluid leakage

Binary variable describing the presence of a uterine dehiscence, regardless of whether it is symptomatic or it is diagnosed at the time of cesarean section

Binary variable describing the presence of a maternal pulmonary edema, regardless of the severity, between the procedure and discharge.

Categorical variable describing if the postnatally assessed neurological level is better / same or worse than the level assessed prenatally before the procedure. It will be assessed by physical examination

Inclusion Criteria: Maternal age > 18 years old Singleton pregnancy Gestational age between 18 0/7 weeks and 26 6/7 weeks Isolated neural tube defect between T1 and S1 Cerebellar herniation (Chiari type II) Exclusion Criteria: Fetal anomalies non related to neural tube defect (NTD) including chromosomal abnormalities Body mass index > 35 kg/m2 Maternal disorders contraindicating surgery Genetic anomalies with poor prognosis Sever kyphosis (>30º)

Maroto A, Illescas T, Melendez M, Arevalo S, Rodo C, Peiro JL, Belfort M, Cuxart A, Carreras E. Ultrasound functional evaluation of fetuses with myelomeningocele: study of the interpretation of results. J Matern Fetal Neonatal Med. 2017 Oct;30(19):2301-2305. doi: 10.1080/14767058.2016.1247262. Epub 2017 Jan 16.

Belfort MA, Whitehead WE, Shamshirsaz AA, Bateni ZH, Olutoye OO, Olutoye OA, Mann DG, Espinoza J, Williams E, Lee TC, Keswani SG, Ayres N, Cassady CI, Mehollin-Ray AR, Sanz Cortes M, Carreras E, Peiro JL, Ruano R, Cass DL. Fetoscopic Open Neural Tube Defect Repair: Development and Refinement of a Two-Port, Carbon Dioxide Insufflation Technique. Obstet Gynecol. 2017 Apr;129(4):734-743. doi: 10.1097/AOG.0000000000001941.