title: Iatrogenic retinal breaks in 20-G versus 23-G pars plana vitrectomy.
abstract: BACKGROUND
  The purpose of this study was to compare the incidence of iatrogenic anterior retinal breaks in 20-G vitrectomy (PPV) with transconjunctival 23-G PPV.
  
  
  METHODS
  Retrospective, observational review study involving consecutive patients undergoing PPV in a single center in the UK during a 2-year period.
  
  
  RESULTS
  Sclerotomy-related entry-site breaks (ESB) were found in 50/628 (7.9 %) 20-G PPV cases and 5/296 (1.7 %) 23-G PPV eyes (p<0.0001*). Anterior non-sclerotomy iatrogenic breaks (ANSB) were present in 55/628 (8.7 %) 20-G PPV cases and 18/296 (6.1 %) 23-G PPV eyes (p=0.19). The incidence of total anterior iatrogenic breaks (ANSB + ESB) was 105/628 (16.7 %) for 20-G PPV and 23/296 (7.8 %) for 23-G PPV (p=0.002*). Univariate analysis showed that posterior vitreous detachment induction was the only risk factor significantly associated with the development of anterior retinal breaks for both 20-G and 23-G PPV. Multivariate logistic model of risk factors for development of iatrogenic retinal breaks demonstrated that 23-G PPV was the most important factor reducing the risk of anterior breaks (p<0.0001*).
  
  
  CONCLUSIONS
  We report the largest series of patients undergoing 20-G and 23-G vitrectomy, where 23-G vitrectomy was associated with a significantly lower incidence of anterior iatrogenic retinal breaks.
authors.affiliation: Manchester Royal Eye Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre and Institute of Human Development, University of Manchester, Manchester, UK.
authors.forename: Assad
authors.initials: A
authors.lastname: Jalil
authors.forename: Whye Onn
authors.initials: WO
authors.lastname: Ho
authors.forename: Stephen
authors.initials: S
authors.lastname: Charles
authors.forename: Felipe
authors.initials: F
authors.lastname: Dhawahir-Scala
authors.forename: Niall
authors.initials: N
authors.lastname: Patton
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D007049:Iatrogenic Disease; D015994:Incidence; D008297:Male; D008866:Microsurgery / Q000009:adverse effects*; D008875:Middle Aged; D012167:Retinal Perforations / Q000209:etiology*; D012189:Retrospective Studies; D012307:Risk Factors; D012599:Sclerostomy; D006113:United Kingdom; D014821:Vitrectomy / Q000009:adverse effects* / Q000379:methods