Date of Award
Master of Science in Vision Science
Robert L. Yolton
Background: The Keeler Pulsair 3000 is a recently introduced non-contact tonometer that is especially useful for children and those for whom sitting at a slit lamp or table-mounted unit would be difficult. In this project, intra-ocular pressures (lOPs) measured by Keeler 3000 and Goldmann tonometers were compared to assess validity and reliability of the Keeler data.
Methods: Two Keeler lOPs (each the mean of four individual air-puff readings) and two Goldmann lOPs were measured for each eye of 113 subjects. Subjects were also asked which measurement technique they preferred.
Results: lOP ranged from 9 to 28 mm Hg. Correlations between the two Goldmann lOPs measured for the right and left eyes were 0.98 and 0.97 respectively. These values are higher than correlations between Keeler and Goldmann measurements (0 .86 to 0.91 ). Keeler lOPs were slightly above Goldmann values for pressures of less than 15mm Hg and slightly below for lOPs over 15 mm Hg. Extrapolation to a Goldmann lOP of 30 mm Hg suggests that the Keeler would read about 6% (1.7 mm Hg) too low at this lOP. Eight eyes (7%) had differences between Keeler and Goldmann lOP readings of 5.0 mm Hg or more. For three eyes, single outlier pressures readings produced by the Keeler caused these differences.
Conclusions: In the range of 10 to 24 mm Hg, the Keeler tonometer produced lOPs that corresponded well with Goldmann values for most eyes and was preferred by the majority of subjects who indicated a preference. The Pulsair 3000 is relatively easy to use by technicians and has numerous special applications in optometric practice.
Lawson-Kopp, Wendy and DeJong, Amy, "Clinical evaluation of Keeler Pulsair 3000 non-contact tonometer" (2001). College of Optometry. 1376.