Age differences in central and peripheral intra-ocular pressure using a rebound tonometer

Abstract

To evaluate the influence of age on the measurements and relationships among central and peripheral IOP readings taken with a rebound tonometer. METHODS: The intraocular pressures were assessed using the ICare(R) rebound tonometer (Tiolat Oy, Helsinki, Finland) on the right eye of two-hundred and seventeen patients (88 males, 129 females), aged 18 to 85 years (meanSD, 45.919.8 years), at the center and at 2 mm from the nasal and temporal limbus along the horizontal meridian. Three age groups were established as being less than 30 years old (n=75), from 31 to 60 years old (n=77) and above 60 years old (n=65). RESULTS: There was a high correlation between central and peripheral IOP readings, with central reading being higher than peripheral ones. The higher IOP values were found within the younger group for the central location. Subjects within the older group (above 60 years of age) presented significantly lower temporal IOP readings than the remaining two groups (p<0.001), while no significant differences were found among groups at central and nasal locations (p=0.099 and p=0.225, respectively). There was a significant decrease in nasal and temporal IOP readings as the age increased (p=0.011 and p=0.006, respectively). CONCLUSION: Older patients displayed lower IOP values than the middle-aged and younger patients in the temporal peripheral location. A negative correlation between age and IOP by rebound tonometry was found in the corneal periphery but not in its center