*6.3.1 IMM repair*

At the moment, the compared outcomes of pre-natal versus post-natal repair of IMM showed that; although prenatal surgery has an increased risk of preterm delivery, pre-natal repair had significantly better outcomes than the post-natal repair. Pre-natal repair for IMM decrease the risk of death and subsequent needs for shunting (nearly at age of 12 months). Also, pre-natal repair improves scores of mental and motor function (at 30 months). However, pre-natal repair was associated with an increased risk of preterm delivery and uterine dehiscence at labor. Therefore, the potential benefits of pre-natal repair must be balanced against the risks of

prematurity and maternal morbidity [61–65]. In a retrospective review of 54 children evaluated for lower extremity neuro-motor function and short-term ambulatory function following fetal myelomeningocele closure, they concluded that fetal myelomeningocele repair results in better than predicted lower extremity neuro-motor function at birth and short-term ambulatory status. However, these children continue to demonstrate movement incoordination which is characteristic for children with Spina-bifida. In retrospective study evaluated the incidence and clinical implications of the development of cutaneously derived intradural inclusion cysts (ICs) following fetal myelomeningocele closure through parental questionnaire. They concluded that intradural ICs can develop following fetal myelomeningocele repair. ICs long-term complications in these children may include deterioration of bladder function, and loss of lower-extremity function after fetal myelomeningocele closure. Koh et al. 2006 compared urodynamic findings in patients who underwent pre-natal closure of IMM with those of patients who underwent post-natal closure. All prenatally treated patients had lower lumbo-sacral lesions on neurological examination. In comparison, 39% of post-natally treated patients showed lack of sphincter activity at newborn examination, with similar findings noted at 1-year evaluation. Regarding bladder function, all pre-natally treated patients showed detrusor overactivity, compared to 38% of post-natally treated patients, up to 1-year evaluation. They concluded that fetal closure of IMM is associated with a higher incidence of complete denervation of the external urethral sphincter and detrusor over-activity compared to post-natal repair. Open fetal IMM closure has been extensively studied and its benefits to the fetus have been proven. Minimally invasive fetoscopic repair is technically difficult, with high risk of membrane separation and premature rupture of membrane, and its benefits to the fetus have not been proved. Therefore, minimally invasive IMM repair still needs further more studies to confirm its validity for clinical applications [66–70].
