title: Fetoscopic laser photocoagulation in twin-to-twin transfusion syndrome: experience from a single institution.
abstract: BACKGROUND
  Twin-to-twin transfusion syndrome (TTTS) is the most common serious complication of monochorionic (MC) twin pregnancies, with perinatal mortality rates of up to 90% if untreated. This study aimed to review the perinatal and perioperative outcomes of MC twin pregnancies treated for TTTS by fetoscopic laser photocoagulation (FLP) since its introduction at KK Women's and Children's Hospital (KKH), Singapore, in 2011.
  
  
  METHODS
  This was a retrospective review of five consecutive patients who underwent FLP of placental anastomoses for TTTS at KKH from June 2011 to March 2014. FLP was offered to patients who were diagnosed with TTTS of at least Quintero Stage II before 26 weeks of gestation. The main outcome measures were perioperative complications and perinatal survival rates.
  
  
  RESULTS
  Five sets of MC twin pregnancies underwent FLP during the study period - three pregnancies were diagnosed with Stage III TTTS and two pregnancies with Stage II TTTS. Median gestational ages at initial presentation, laser photocoagulation and delivery were 19 (range 17-20) weeks, 20 (range 19-23) weeks and 29 (range 28-34) weeks, respectively. One patient had bleeding into the amniotic cavity intraprocedurally. Overall, the perinatal survival rate, double-infant survival rate and survival rate for at least one twin were 60% (6/10 fetuses), 40% (2/5 twins) and 80% (4/5 twins), respectively.
  
  
  CONCLUSIONS
  FLP is a feasible treatment for TTTS, with minimal maternal complications. Perinatal survival rates of this patient group that was managed at our centre were comparable to those of international centres.
authors.affiliation: Department of Maternal Fetal Medicine, KK Women's and Children's Hospital, Singapore.
authors.forename: Edwin
authors.initials: E
authors.lastname: Thia
authors.affiliation: Department of Obstetrics and Gynaecology, KK Women's and Children's Hospital, Singapore.
authors.forename: Serene
authors.initials: S
authors.lastname: Thain
authors.affiliation: Department of Maternal Fetal Medicine, KK Women's and Children's Hospital, Singapore.
authors.forename: George Sh
authors.initials: GS
authors.lastname: Yeo
mesh_terms: D000328:Adult; D005260:Female; D005330:Fetofetal Transfusion / Q000628:therapy*; D005332:Fetoscopy / Q000379:methods; D006801:Humans; D017075:Laser Coagulation / Q000379:methods; D011247:Pregnancy; D059285:Pregnancy, Twin; D012189:Retrospective Studies; D012846:Singapore; D016896:Treatment Outcome
keywords: fetofetal transfusion; fetoscopic laser photocoagulation; monochorionic