Significance of dynamic contour tonometry in evaluation of progression of glaucoma in patients with a history of laser refractive surgery

Abstract

AimsIn this study, we tested the hypothesis that intraocular pressure (IOP) parameters measured by dynamic contour tonometry (DCT) would be more relevant in progression of glaucoma when there is a history of laser refractive surgery (LRS) than the IOP parameters measured by Goldmann applanation tonometry (GAT) or calculated by correction formulae.MethodsNinety-eight eyes in 54 patients with open-angle glaucoma and a history of LRS were included in this retrospective study. IOP was measured by both GAT and DCT during follow-up. Baseline, mean, and peak IOP, IOP fluctuation, and IOP reduction were measured by each tonometry method. Corrected IOP parameters using central corneal thickness and mean keratometry values were also analysed. Clustered logistic regression was used to identify variables correlated with progression of glaucoma. Areas under the curve (AUCs) for correlated variables were also compared.ResultsThe mean DCT value (OR 1.36, p=0.024), peak DCT value (OR 1.19, p=0.02) and pattern SD (OR 1.10, p=0.016) were significant risk factors for progression. There was a significant difference in the predictive ability of the mean DCT and GAT values (AUC 0.63 and 0.514, respectively; p=0.01) and of the peak DCT and GAT values (0.646 and 0.503, respectively, p=0.009). The AUCs for corrected IOP did not exceed those of DCT.ConclusionsIOP measurements were more associated with progression of glaucoma when measurements were obtained by DCT than by GAT or correction formulae in eyes with a history of LRS.

Evaluating Intraocular Pressure after Myopic Photorefractive Keratectomy: A Comparison of Different Tonometers

“…Since the devices evaluated might cause different corneal deformation, a fixed order of IOP measurements was followed instead of using a random one, as used in previously published studies. [20][21][22][23] This choice might explain the different results reported in other papers on the same topic. [21][22][23] It is easy to imagine that no contact tonometry To reduce statistical bias, only 1 eye of each patient was included to avoid the incidence of inner correlations between the 2 eyes, as occurs in pairs of organs.…”

“…To limit potential errors, a well-trained, physician performed measurements with only 1 device, unaware of the results obtained with the other tonometers, and a sixth physician collected the values. Since the devices evaluated might cause different corneal deformation, a fixed order of IOP measurements was followed instead of using a random one, as used in previously published studies 20–23. This choice might explain the different results reported in other papers on the same topic 21–23.…”

Factors Associated With Differences in the Initial Location of Structural Progression in Normal-Tension Glaucoma

“…Four IOP parameters were used in this study. 6 The IOP measured before the medical treatment was defined as the pretreatment IOP (pre-IOP). The average and maximum of the IOP values measured during follow-up after starting the medical treatment were recorded as the mean IOP and peak IOP, respectively.…”

How to Measure Intraocular Pressure: An Updated Review of Various Tonometers

“…The DCT has been shown to be less influenced by the properties of the cornea and can be therefore helpful in taking IOP readings in subjects with previous photorefractive surgeries [ 112 , 113 , 114 , 115 , 116 ]. The DCT has shown high precision, with higher reproducibility than GAT [ 109 , 117 ].…”