title: A definition of selectivity in laser coagulation of chorionic plate anastomoses in twin-to-twin transfusion syndrome and its relationship to perinatal outcome.
abstract: OBJECTIVE
  This study was undertaken to correlate selectivity of surgery and perinatal outcome in twin-to-twin transfusion syndrome treated by endoscopic laser coagulation, using a quantitative definition of selectivity.
  
  
  METHODS
  287 consecutive cases of severe twin-to-twin transfusion syndrome were reviewed. A selectivity index was built as the ratio of selective over nonselective coagulations per procedure. Outcome measures were survival at 28 days and failure of surgery as defined by recurrence of twin-to-twin transfusion syndrome or fetofetal hemorrhage.
  
  
  RESULTS
  Two populations were identified: a high selectivity group (63.8%) and a low selectivity group (36.2%). Survival of at least one twin and survival of both twins were higher in the high-selectivity group (p = .007 and p = .04 respectively). Failure of surgery rates were similar in both groups.
  
  
  CONCLUSIONS
  A quantitative definition of selectivity appears justified by the large variations found in the practice of a single center and by significant differences in outcome. Survival is significantly improved in highly selective procedures.
authors.affiliation: Department of Obstetrics and Gynecology, Centre Hospitalier Intercommunal-Poissy Saint-Germain-en-Laye, Poissy, France.
authors.forename: Julien J
authors.initials: JJ
authors.lastname: Stirnemann
authors.forename: Bernard
authors.initials: B
authors.lastname: Nasr
authors.forename: Edwin
authors.initials: E
authors.lastname: Quarello
authors.forename: Lisa
authors.initials: L
authors.lastname: Ortqvist
authors.forename: Malek
authors.initials: M
authors.lastname: Nassar
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Bernard
authors.forename: Yves
authors.initials: Y
authors.lastname: Ville
mesh_terms: D000714:Anastomosis, Surgical / Q000379:methods; D002823:Chorion / Q000601:surgery*; D005260:Female; D005330:Fetofetal Transfusion / Q000000981:diagnostic imaging / Q000601:surgery*; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D017075:Laser Coagulation / Q000379:methods*; D011181:Postnatal Care; D011247:Pregnancy; D011256:Pregnancy Outcome; D018607:Pregnancy Reduction, Multifetal; D011272:Pregnancy, Multiple; D011336:Probability; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D016216:Ultrasonography, Prenatal