Klinischer Vergleich eines neu entwickelten Prototyps zur Messung der Hornhautsensibilität zum aktuellen Goldstandard

Abstract

Purpose. The aim of the study was to test a newly developed prototype for corneal sensitivity measurement (liquid jet (LJ) with saline as stimulus) for repeatability and correlation with the Cochet-Bonnet esthesiometer (CB). This is an excerpt of a master thesis, which was part of a larger study Material and Methods. Corneal sensitivity thresholds (CST) were determined for 30 subjects, in a clinical trial with 30 subjects, with each device on two separate dates (with inter- vals of at least one day and a maximum of fourteen days). In addition, the pain sensitivity questionnaire (PSQ) was applied to determine any possible correlation with corneal sensitivity. Results. Similar standard deviations of the CSTs for LJ and CB were obtained (LJ (M ± SD): 24.3 ± 2.0 dB; CB (M ± SD): 20.0 ± 2.0 dB). No statistically significant difference in CST was found between the two visits for LJ (mean differen- ce: -0.063 dB, p = 0.78), however there was a statistically significant difference for CB (mean difference: -0.641 dB, p = 0.003). LJ CSTs correlated moderately positively with CB CSTs and PSQ (LJ-CB: r = 0.476, p < 0.001; LJ-PSQ: r = 0.437, p < 0.001). Conclusion. LJ offers a significantly larger stimulus bandwidth than CB. Better reproducibility was observed for LJ, while correlation between the results for the two instruments was good. Significant moderate positive correlation was found between LJ CSTs and general pain sensitivity. Keywords esthesiometry, Cochet-Bonnet, Liquid Jet, prototype, PSQ