Abstract
Purpose :
The Goldmann applanation tonometry (GAT) is the gold standard for intraocular pressure (IOP) measurement in clinical practice, but its results might be affected by corneal biomechanical properties. For this reason, different new tonometry devices have been established with the aim to provide a correct IOP assessment independent of corneal biomechanics. In a cross-sectional, observational study we investigated the consistency of GAT results with the Ocular Response Analyzer (ORA), the Dynamic Contour Tonometer (DCT) and the Corvis ST (CST) in healthy subjects.
Methods :
IOP measurements with GAT (GAT-IOPc), ORA (IOPcc), DCT (DCT-IOP) and CST (bIOP) were performed in 94 eyes of 94 healthy subjects (45.6 ± 17.2 years) with no prior ocular/corneal diseases or surgical interventions. IOP values of the different tonometers were analyzed with ANOVA for repeated measurements. To check for an influence of central corneal thickness (CCT) Pearon`s correlation coefficient was used.
Results :
The mean GAT-IOPc in all subjects was 12.9 ± 2.4 mmHg, the mean DCT-IOP was 16.1 ± 2.6 mmHg and the mean IOPcc was 15.6 ± 3.3 mmHg which was significantly higher than the GAT-IOPc (P < 0.0001). The mean bIOP was 13.5 ± 2.4 mmHg which was higher but not significantly different from GAT-IOPc (P = 0.146). Correlation analysis of IOP values and CCT revealed only a weak and positive correlation to GAT-IOPc (r = 0.244; P = 0.021). However, the IOP measurements with the ORA, the DCT and the CST showed no significant correlation to CCT.
Conclusions :
All tonometry devices showed a good consistency of IOP with GAT. As no influence of CCT in IOPcc, DCT-IOP and bIOP was detectable, the used correction algorithms appear to be appropriate in these tonometers in the clinical setting. The highest accordance was found between GAT-IOPc and bIOP. Further studies are needed to elucidate the role of bIOP for IOP measurement.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.