[Significance of the corneal thickness in non-contact tonometry]

Klin Monbl Augenheilkd. 1991 Sep;199(3):183-6. doi: 10.1055/s-2008-1046068.
[Article in German]


In this study the Reichert non-contact tonometer (NCT II) was compared with the Goldmann applanation tonometer (GAT) in 25 subjects (50 eyes; pressure range 9-17 mmHg). The relationship NCT/GAT fulfilled the conditions required for legal verification. Marked differences between the readings of both instruments can be caused by anomalous central corneal thickness, because non-contact tonometry is influenced more than conventional applanation tonometry by the corneal thickness. Starting from a central thickness of 0.51 mm, the NCT is assumed to underestimate the actual intraocular pressure in eyes with thinner and to overestimate it in eyes with thicker cornea by 1 mmHg per 0.01 mm difference of corneal thickness. This value changes with individual corneal tissue qualities and is not valid especially in presence of corneal edema.

Publication types

  • Comparative Study
  • English Abstract

MeSH terms

  • Adult
  • Cornea / physiopathology*
  • Corneal Edema / physiopathology*
  • Female
  • Humans
  • Intraocular Pressure / physiology*
  • Male
  • Middle Aged
  • Reference Values
  • Tonometry, Ocular / instrumentation*