Abstract
Purpose::
The goal of this study was to evaluate Goldmann and corneal-compensated intraocular pressure (IOP), central corneal thickness (CCT) and corneal hysteresis in patients with diagnosis of Rheumatoid Arthritis (RA).
Methods::
A total of 19 eyes of 10 patients with RA were included in the study group. A total of 30 eyes of 15 race-, and gender-matched healthy volunteers were included in the control group. All subjects underwent a complete ophthalmic evaluation and patients presenting any significant ocular disease were excluded. IOP was measured using Goldmann applanation tonometer (GAP), Pascal Dynamic Contour Tonometer (DCT) and Ocular Response Analyzer (ORA) in a random sequence. Corneal hysteresis was evaluated by ORA and central corneal thickness (CCT) by ultrasound pachymeter. Three measurements of each device were taken and the mean measurements were used for the analysis. The difference between IOP readings with the 3 methods was analyzed in each group. Corneal hysteresis and CCT was compared between the two groups.
Results::
All patients with RA included in this study were female. The mean (SD) CCT in the RA and control group was 536 (24) µm and 538 (32) µm, respectively (P=0.82). In the study group the mean (standard deviation [SD]) IOP was 10.1 (2.4) mmHg for the GAP; 15.8 (2.6) mmHg for the ORA; and 16.2 (2.2) mmHg for DCT. In the control group mean (standard deviation [SD]) IOP was 13.9 (2.5) mmHg for GAP; 15.4 (3.1) mmHg for the ORA; and 16.1 (2.8) mmHg for DCT. The mean of corneal hysteresis in RA group and in the control group were respectively, 9.5 (SD=1.4) and 10.4 (SD=1.5). The difference between the two groups were statistically significant (p=0.027).
Conclusions::
The IOP results using GAP were lower when compared with the DCT and ORA in both groups, and this difference was higher in the RA group. The CCT was within the normal range in both groups. These findings could be explained by the corneal hysteresis, which is lower in patients with Rheumatoid Arthritis than in normal patients.
Keywords: intraocular pressure • cornea: basic science • clinical (human) or epidemiologic studies: systems/equipment/techniques