Tonometry in keratoconus

Relevance Measuring intraocular pressure (IOP) in keratoconus (KC) is associated with significant difficulties: due to corneal protrusion and changes in its biomechanical properties [1–3]. The results of using the most common methods have a large error. The emergence of new tonometry methods that are less dependent on the biomechanical properties of the cornea made it possible to partially level out this error. The results of Goldman tonometry and pneumotonometry are often underestimated due to changes in the cornea in keratoconus [4]. Modern tonometric methods - ORA, Corvis ST, PASCAL, Icare - are preferred when measuring IOP in patients with KC [5]. Conclusion The emergence of modern tonometry methods has significantly improved the reliability of intraocular pressure studies in keratoconus, as well as studied the biomechanical properties of the cornea in vivo. Keywords: cornea; keratoconus; tonometry; intraocular pressure; hydrodynamics; "gold standard"