Impressions- und Applanationstonometrie bei pathologischen Hornh�uten im Vergleich mit der intraokularen Nadeldruckmessung

Abstract

In corneal pathology both, applanation tonometry and impression tonometry do not deliver reliable results on an average. Only intraocular needle-tonometry delivers reliable results in these eyes.

Temporal contrast sensitivity using full-field flicker test (Erlangen flicker test) in patients after penetrating keratoplasty

“…Reasons for mismeasurement of the IOP by indirect means after PK may result from biomechanical changes within the graft, in contrast to the normal corneas for which Goldmann applanation tonometry was originally designed [36]. Indeed, IOP has often been measured higher with direct needle puncture of the anterior chamber than with Perkins applanation tonometry after PK [22,23]. Although this invasive method of direct IOP assessment is reserved to a few critical cases after PK, it may well be assumed that direct intraocular needle measurement of the IOP directly before trepanation in combination with preoperative or very early postoperative assessment of the size and cupping of the optic disc as well as the chamber angle will enable more reliable classification of an eye in terms of having "glaucoma" before PK.…”

Comparison of intraocular tonometry using three different non-invasive tonometers in children

“…Amaral et al described an influence of CCT on IOP readings, particularly when taken in peripheral regions of the cornea [1]. On the other hand, there are data demonstrating that CCT`s influence has not been completely eliminated, and that all applanation and indentation tonometers, including the Tono-Pen XL, correlated to CCT [7,20]. We thus excluded patients with obvious corneal abnormalities or oedema from our examination.…”

“…While measurements with the Tono-Pen XL showed no age effects, underestimation decreased with increasing age when measured with the Perkins [8]. In eyes with corneal pathology, applanation (GAT, Perkins) and impression (Schiötz) tonometry underestimated the IOP in adults when compared to needle tonometry [20].…”

“…The method of invasive intraocular needle tonometry has been shown to be accurate, becoming a gold standard for comparison with other devices [20]. However, such comparisons have not been performed in glaucomatous paediatric eyes.…”

Funktionelle Ergebnisse der perforierenden Keratoplastik bei Pseudoexfoliationssyndrom (PEX)-Keratopathie

“…Madjlessi u. Mitarb. konnten zeigen, dass auch die Impressionstonometrie bei pathologischen Hornhautveränderungen der Applanationstonometrie nicht überlegen ist[8]. Beide Verfahren liefern im Vergleich zur elektronischen intraokularen Nadeldruckmessung durchschnittlich die gleichen falsch niedrigen Werte[8].…”