title: Sono-endoscopic delineation of the placental vascular equator prior to selective fetoscopic laser ablation in twin-to-twin transfusion syndrome.
abstract: OBJECTIVE
  To assess the safety and efficacy of a new fetoscopic technique in the management of twin-to-twin transfusion syndrome.
  
  
  METHODS
  Prospective study of fetoscopic treatment and outcome in 10 pregnancies complicated by severe twin-to-twin transfusion syndrome before 24 weeks' gestation. The sono-endoscopic approach was used to identify the placental vascular equator and photocoagulate any vessels crossing this threshold.
  
  
  RESULTS
  The mean gestation at treatment was 20 weeks and 3 days. An average of three to four vessels were ablated during each procedure, with a mean operative time of 24 min (range, 14-31 min). The overall survival rate was 55% (11 of 20) with at least one survivor in 70% (seven of 10) of pregnancies.
  
  
  CONCLUSIONS
  Fetoscopic laser ablation is a safe and effective form of treatment in the management of severe twin-to-twin transfusion syndrome. This technique, where vessels crossing the placental vascular equator are identified and photocoagulated fetoscopically, is an alternative to the non-selective and selective methods described previously. This new approach is associated with a shorter operating time, less damage to the normal placental surface vasculature and with survival results that are at least as promising as previously reported techniques.
authors.affiliation: Fetal Medicine Unit, St George's Hospital Medical School, Academic Department of Obstetrics and Gynaecology, Cranmer Terrace, London, SW17 ORE UK.
authors.forename: B
authors.initials: B
authors.lastname: Thilaganathan
authors.forename: D J
authors.initials: DJ
authors.lastname: Gloeb
authors.forename: S
authors.initials: S
authors.lastname: Sairam
authors.forename: A
authors.initials: A
authors.lastname: Tekay
mesh_terms: D019160:Endosonography; D005260:Female; D005330:Fetofetal Transfusion / Q000601:surgery*; D005865:Gestational Age; D006801:Humans; D053685:Laser Therapy; D008028:Light Coagulation; D010920:Placenta / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011446:Prospective Studies; D016216:Ultrasonography, Prenatal