Fetal intervention for myelomeningocele: Effect on postnatal bladder function

Purpose: Myelomeningocele is the most common congenital malformation of the central nervous system noted on prenatal ultrasound.. Due to its significa nt postnatal sequelae, treatment in utero could potentially have a profound impact on the :newborn. Others have reported fetal surgical techniques for in utero repair of myelomeningocele and its potential benefits on motor an d neurological function. We report our urodynamic findings in the newborn a fter in utero repair of spina bifida in an effort to characterize postnatal bladder function. Materials and Methods: A retrospective review of the fetal surgery database at University of California San Francisco was performed identifying patien ts with a diagnosis of myelomeningocele. Prenatal surgical repair of myelom eningocele was considered if a normal karyotype was present, no other signi ficant congenital anomalies were evident and gestational age was less than 24 weeks. The spinal defects were in the lumbar or lumbosacral region. All surgery was performed before 24 weeks of gestations. Results: Fetal surgery to correct myelomeningocele was performed in 6 patie nts. All patients were born premature at 32 weeks of gestation or less. Vid eourodynamics performed at age 1 month in 4 patients indicated decreased bl adder capacity for weight, increased detrusor storage pressures and signifi cant post-void residual. Hydronephrosis was demonstrated in 4 patients on r enal/bladder ultrasound, and moderate vesicoureteral reflux was seen in 3. Conclusions: Patients with spinal bifida treated in utero appear to have th e same changes in urodynamic parameters and anatomical abnormalities in the urinary tract as other children with spinal defects who have undergone sta ndard postnatal care. In utero treatment of spinal bifida may expose the ne wborn to the effects of prematurity. The long-term effects on bladder funct ion in the fetus after in utero repair of myelomeningocele remain unknown. A randomized controlled trial is necessary to evaluate long-term bladder fu nction as well as other outcome variables in this experimental approach to patients with myelomeningocele.