ABSTRACT
PURPOSE: To investigate the accuracy of intraocular pressure (IOP) measurement through a plano soft contact lens (SCL) in situ by a noncontact tonometer (NCT) and a rebound tonometer (RBT). METHODS: The IOP of 66 eyes of 33 subjects with no ocular pathology was measured by NCT (tonometer CT-80, TOPCON, Japan) and RBT (iCare rebound tonometry(TM), Tiolat Oy, Finland). IOP measurement was repeated through plano SCL (ACUVUE OASYS(R), Johnson & Johnson Vision Care Inc., USA) in situ. Statistical analysis was performed using the paired t-test. RESULTS: Mean IOP measured by NCT was 13.10 +/- 2.52 mmHg without SCL and 12.95 +/- 2.56 mmHg with SCL. Mean IOP measured by RBT was 14.13 +/- 2.94 mmHg without SCL and 13.84 +/- 2.75 mmHg with SCL. No significant statistical differences were found between IOP measured with and without SCL (p=0.47, p=0.11 respectively). CONCLUSIONS: Reliable measurement of IOP by NCT and RBT can be achieved through plano SCL.
Subject(s)
Contact Lenses, Hydrophilic , Eye , Intraocular Pressure , Vision, OcularABSTRACT
PURPOSE: To compare the rebound tonometer with the TonoPen for measuring the intraocular pressure (IOP) in rats METHODS: Chronic IOP elevation models were induced unilaterally in nine Sprague-Dawley rats by applying an argon laser to the trabecular meshwork. IOP was measured before laser treatment and at one, two, and three days following laser treatment. Two independent operators collected five readings of the rebound tonometer and the TonoPen. Correlation analysis and comparison with the Bland & Altman method were performed. The intraclass correlation coefficient of each measurement and the difference between two independent operators were calculated. RESULTS: The IOP values measured with the rebound tonometer were well correlated with those of the TonoPen (r=0.676, p<0.001); however, the mean difference expressed as the percent difference of the averages of two tonometers, was 27.5%. The IOP values measured with a rebound tonometer exhibited a significantly higher intraclass correlation coefficient (0.966; 95% CI, 0.945-0.980 vs 0.412; 95% CI, 0.264-0.581) and a lower difference between the two operators (3.10+/-2.17 mmHg vs 6.17+/-5.17 mmHg) than those of the TonoPen. CONCLUSIONS: Although the IOP values measured with the rebound tonometer were lower than those of the TonoPen, they were in good agreement and were less variable than those of the TonoPen.