title: Determination of normal values of intraocular pressure and central corneal thickness in healthy premature infants-a prospective longitudinal study.
abstract: To evaluate the longitudinal change of intraocular pressure (IOP) and central corneal thickness (CCT) in healthy premature infants.
  
  
  
  Premature infants born at 28 weeks' gestational age were included in this prospective, single-center longitudinal study. IOP was measured by handheld applanation tonometer (Tono-Pen Avia); CCT measurements were performed by ultrasonic pachymeter. Examinations were held at 32 weeks' gestational age initially and at 2-week intervals thereafter for a total of 5 consecutive measurements by the same ophthalmologist.
  
  
  
  A total of 110 right eyes of 110 healthy premature infants were analyzed. The mean IOP at 32 weeks' gestational age was 18.28 ± 2.78 mm Hg; mean CCT, 670.56 ± 55.72 μm. Mean IOP and CCT thereafter were 16.13 ± 2.20 mm Hg and 613.67 ± 48.11 μm in week 34, 14.67 ± 2.04 mm Hg and 579.24 ± 43.73 μm in week 36, 13.49 ± 2.08 mm Hg and 551.91 ± 40.75 μm in week 38, and 13.21 ± 1.94 mm Hg and 546.18 ± 38.70 μm in week 40. The longitudinal changes of mean IOP and CCT values between 5 consecutive measurements were statistically significant (P < 0.001, for each).
  
  
  
  IOP and CCT values decrease longitudinally in healthy premature infants between 32 and 40 weeks' gestational age. Elevated IOP values, which were identified in the early premature period, seem to be associated with higher CCT values.
authors.affiliation: Department of Ophthalmology, Zekai Tahir Burak Women's Health Training and Research Hospital, Ankara, Turkey. Electronic address: erginturk@yahoo.com.
authors.forename: Damla
authors.initials: D
authors.lastname: Erginturk Acar
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Ugur
authors.initials: U
authors.lastname: Acar
authors.affiliation: Department of Ophthalmology, Zekai Tahir Burak Women's Health Training and Research Hospital, Ankara, Turkey.
authors.forename: Ozdemir
authors.initials: O
authors.lastname: Ozdemir
authors.affiliation: Department of Ophthalmology, Zekai Tahir Burak Women's Health Training and Research Hospital, Ankara, Turkey.
authors.forename: Zuhal Ozen
authors.initials: ZO
authors.lastname: Tunay
mesh_terms: D003315:Cornea / Q000033:anatomy & histology*; D063171:Corneal Pachymetry; D005260:Female; D005865:Gestational Age; D064368:Healthy Volunteers; D006801:Humans; D007223:Infant; D007234:Infant, Premature; D007429:Intraocular Pressure / Q000502:physiology*; D008137:Longitudinal Studies; D008297:Male; D009929:Organ Size; D011446:Prospective Studies; D012016:Reference Values; D014065:Tonometry, Ocular