title: Measurement of intraocular pressure after epikeratophakia.
abstract: OBJECTIVE
  To assess the accuracy of three commonly used tonometers in eyes after epikeratophakia.
  
  
  METHODS
  Five eye bank eyes with sutured epikeratophakia buttons were connected to a manometer and a pressure transducer. Intraocular pressure was adjusted in 5 mm Hg increments from 0 to 50 mm Hg. The intraocular pressure was measured at each increment using a Goldmann tonometer, a pneumatonometer, and a Tono-pen.
  
  
  RESULTS
  The difference between the manometer (actual pressure) and the Goldmann tonometer ranged from -19 to +9 mm Hg (mean (SD) overestimation 2.6 (5.8) mm Hg). The pneumatonometer error ranged from -27.5 to +5.5 mm Hg (mean (SD) overestimation 4.7 (6.1) mm Hg), and for the Tono-pen the range was -18 to +11 mm Hg (mean (SD) overestimation 0.05 (7.9) mm Hg). The correlation coefficients for the three tonometers were 0.94, 0.92, and 0.87 for the Goldmann tonometer, pneumatonometer, and Tono-pen respectively.
  
  
  CONCLUSIONS
  The Goldmann tonometer had the best correlation with the manometer in eye bank eyes with epikeratophakia (correlation coefficient 0.94), but none of the tonometers was accurate over the entire range of pressures tested. Detection of glaucoma in eyes with epikeratophakia cannot rely on tonometry alone, but requires examination of the optic nerve and visual field.
authors.affiliation: Department of Ophthalmology, University of Minnesota, USA.
authors.forename: M M
authors.initials: MM
authors.lastname: Wright
authors.forename: A L
authors.initials: AL
authors.lastname: Grajewski
mesh_terms: D016022:Case-Control Studies; D017391:Epikeratophakia; D006801:Humans; D011184:Postoperative Period; D014065:Tonometry, Ocular / Q000295:instrumentation*