title: [Comparison of precision of the TonoPenXL with the Goldmann and Draeger applanation tonometer in a sitting and recumbent position of the patients -- a clinical study on 251 eyes].
abstract: OBJECTIVE
  Comparison of precise intraocular pressure (IOP) measurement with TonoPenXL, Goldmann and Draeger applanation tonometer in a sitting and recumbent position.
  
  
  METHODS
  The IOP of 251 eyes of 127 consecutive patients (SFB 539) was measured prospectively in a sitting position (1 x Goldmann, 3 x TonoPenXL) and in recumbent position (1 x Draeger, 3 x TonoPen). The mean of three TonoPenXL measurements was only accepted in a 5 % interval. Additionally, corneal ultrasonic pachymetry (Tomey, AL-2000), central corneal power, refractive error, gender and age were registered.
  
  
  RESULTS
  The IOP measured with the TonoPenXL was in 92 % in a range of 2 mm Hg from the Goldmann standard. In a vertical position, the IOP TonoPenXL (16.7 +/- 4.5 mm Hg) was 0.2 mm Hg lower than the IOP Goldmann (16.9 +/- 5.1 mm Hg; regression analysis: IOP TonoPenXL = 1.78 + 0.88 IOP Goldmann). In a horizontal position, the IOP TonoPenXL (17.5 +/- 5.0 mm Hg) was 0.5 mm Hg higher as the IOP Draeger (17.0 +/- 5.3 mm Hg; regression analysis: IOP TonoPen = 0.34 + 1.016 IOP Draeger). Using the TonoPenXL, the IOP was 0.8 mm Hg higher in recumbent position than in a sitting position (regression analysis: IOP TonoPen recumbent position = - 2.27 + 1.19 IOP TonoPen sitting position). We found no relationship found between central corneal power, central corneal thickness and IOD measured with the TonoPenXL.
  
  
  CONCLUSIONS
  The TonoPenXL is useful for IOP measurement in a sitting and recumbent position. The results are reproducible in 92% with the Goldmann-applanation tonometer. The ophthalmologist has a comfortable measurement and screening tool for consultations or IOP investigation under general anaesthesia.
authors.affiliation: Augenklinik mit Poliklinik, Universität Erlangen-Nürnberg, Erlangen. Arne.Viestenz@t-online.de
authors.forename: Arne
authors.initials: A
authors.lastname: Viestenz
authors.forename: Berthold
authors.initials: B
authors.lastname: Lausen
authors.forename: Anselm M
authors.initials: AM
authors.lastname: Jünemann
authors.forename: Christian Y
authors.initials: CY
authors.lastname: Mardin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004867:Equipment Design; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction / Q000706:statistics & numerical data; D011187:Posture / Q000502:physiology*; D012015:Reference Standards; D012044:Regression Analysis; D014065:Tonometry, Ocular / Q000295:instrumentation* / Q000592:standards