title: Incidence of retinopathy of prematurity in extremely premature infants over an 18-year period.
abstract: BACKGROUND
  To report the incidence of retinopathy of prematurity (ROP) in a subgroup of extremely premature infants admitted to an Australian tertiary centre over an 18-year period.
  
  
  METHODS
  Retrospective study. Royal Brisbane and Women's Hospital Neonatal Intensive Care Unit.
  
  
  METHODS
  Five hundred and fifty-four infants admitted between 23 and 25.6 weeks gestational age (GA).
  
  
  METHODS
  The 18-year study was divided into three 6-year periods for analysis: period 1 (1992-1997), period 2 (1998-2003) and period 3 (2004-2009). Infants were compared based on their week of GA and by the study period in which they were born.
  
  
  METHODS
  GA, birthweight, incidence and severity of ROP.
  
  
  RESULTS
  Three hundred seventy-three (67.3%) infants survived until ROP screening, and 351 (63.4%) survived until discharge. ROP incidence increased from 78.2% in period 1 to 86.1% in period 3. Over the entire study, 90.5% of 23-week GA infants had ROP compared with 89.7% of 24-week GA infants and 76.1% of 25-week GA infants. Mean birthweight was significantly lower in infants with any ROP (725.1 g) and ROP of at least stage 3 (720.8 g) compared with infants without ROP (806.5 g) (P < 0.0001). Twenty-three-week GA infants had more severe ROP (28.6%) than 24 weeks (18.3%) and 25 weeks GA (11.9%).
  
  
  CONCLUSIONS
  There has been increased survival and incidence of ROP in extremely premature infants over the past 20 years. Lower birthweight and GA are both associated with higher incidence and more severe ROP.
authors: Department of Ophthalmology, Royal Children's Hospital, Brisbane, Queensland, Australia.
authors: David J
authors: DJ
authors: Gunn
authors: David W
authors: DW
authors: Cartwright
authors: Glen A
authors: GA
authors: Gole
mesh_terms: D001315:Australia / Q000453:epidemiology; D001724:Birth Weight; D005260:Female; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D052577:Infant, Extremely Low Birth Weight; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal / Q000706:statistics & numerical data; D053685:Laser Therapy; D054023:Lasers, Semiconductor / Q000627:therapeutic use; D008297:Male; D012178:Retinopathy of Prematurity / Q000175:diagnosis / Q000453:epidemiology* / Q000601:surgery; D012189:Retrospective Studies; D015996:Survival Rate