Clinical evaluation of the Keeler Pulsair 3000 non-contact tonometer.
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, intraocular pressures (IOPs) measured by Keeler Pulsair 3000 and Goldmann tonometers were compared to assess validity and reliability of the Pulsair 3000 data.


METHODS
Two Pulsair 3000 IOPs (each the mean of four individual air-puff readings) and two Goldmann IOPs were measured for each eye of 113 subjects. Subjects were also asked which measurement technique they preferred.


RESULTS
IOPs ranged from 9 to 28 mmHg. Correlations between the two Goldmann IOPs measured for the right and left eyes were 0.98 and 0.97, respectively. These values are higher than correlations between Pulsair and Goldmann measurements (0.86 to 0.91). Pulsair 3000 IOPs were slightly above Goldmann values for pressures of less than 15 mmHg and slightly below for IOPs greater than 15 mmHg. Extrapolation to a Goldmann IOP of 30 mmHg suggests the Pulsair 3000 would read about 6% (1.7 mmHg) too low at this IOP. Eight eyes (7%) had differences between Pulsair 3000 and Goldmann IOP readings of 5.0 mmHg or more. Single outlier pressures accounted for these differences in three out of the eight eyes.


CONCLUSIONS
In the range of 10 to 24 mmHg, the Pulsair 3000 tonometer produced IOP readings 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 (e.g. measuring IOPs for pediatric patients and those with compromised corneas).
D004867:Equipment Design; D006801:Humans; D007429:Intraocular Pressure; D014065:Tonometry, Ocular / Q000295:instrumentation* / Q000592:standards*