title: Current applications of in utero intervention for lower urinary tract obstruction.
abstract: OBJECTIVE
  Since the early 1980s with the inception of fetal intervention for obstructive uropathy, there have been creative attempts to improve both perinatal and long-term outcomes. Despite advances in technology and an improved understanding of lower urinary tract obstruction (LUTO) in the fetus, the results for these therapeutic interventions remain guarded and the long-term renal morbidity among survivors remains problematic.
  
  
  RESULTS
  Fetal LUTO represents a range of disorders but the most common of these is posterior urethral valves (PUVs). Selection criteria for candidates of possible intervention have improved with our understanding of fetal renal physiology. Serial urinalysis has marginally improved our ability to predict those that may ultimately respond to treatment [1,2], but the potential in the development of biomarkers for renal development or maldevelopment holds greater promise [3]. Advancements in fetal surgery may result in less fetal and maternal morbidity, but limited long-term improvement in outcomes highlights the controversial nature of the various interventions [4-10]. We must counsel families that fetal surgery offers hope but we cannot allow them to hold unrealistic expectations for cure.
  
  
  CONCLUSIONS
  In appropriately selected fetuses, intervention may improve perinatal survival but not without risk to mother and fetus. Long-term renal outcomes remain problematic amongst survivors. In the case of PUV, postnatal primary valve ablation remains the cornerstone of treatment for nephron preservation; however, our ability to mimic these results in the prenatal population remains poor [11]. Disease severity has likely predetermined those that will survive through the perinatal period with or without intervention. Nonetheless, our drive to assess and manage fetal obstructive uropathy perseveres so that we may ultimately relieve obstruction and preserve renal and lung function. We must maintain optimism that continued advances will ultimately improve outcomes, but also be realistic with our current expectations. This paper reviews the status of current in utero interventions and outcomes.
authors.affiliation: University of Virginia Children's Hospital/University of Virginia School of Medicine, Charlottesville, VA, USA. Electronic address: ls2zr@hscmail.mcc.virginia.edu.
authors.forename: L I
authors.initials: LI
authors.lastname: Smith-Harrison
authors.affiliation: University of Virginia Children's Hospital/University of Virginia School of Medicine, Charlottesville, VA, USA. Electronic address: hyh7dn@virginia.edu.
authors.forename: Helen Y
authors.initials: HY
authors.lastname: Hougen
authors.affiliation: University of Virginia Children's Hospital/University of Virginia School of Medicine, Charlottesville, VA, USA. Electronic address: mdt4r@virginia.edu.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Timberlake
authors.affiliation: University of Virginia Children's Hospital/University of Virginia School of Medicine, Charlottesville, VA, USA. Electronic address: STC2U@hscmail.mcc.virginia.edu.
authors.forename: Sean T
authors.initials: ST
authors.lastname: Corbett
mesh_terms: D005260:Female; D005315:Fetal Diseases / Q000601:surgery*; D005333:Fetus / Q000601:surgery*; D006801:Humans; D011247:Pregnancy; D014524:Urethral Obstruction / Q000601:surgery*; D001748:Urinary Bladder Neck Obstruction / Q000601:surgery*; D013520:Urologic Surgical Procedures / Q000379:methods
keywords: Fetal; Fetoscopy; In utero; Intervention; Obstructive uropathy; Surgery