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Measurement of intraocular pressure with pressure phosphene tonometry in children
Dorothy S P Fan1, Thomas Y H Chiu, Nathan Congdon
1Department of Ophthalmology & Visual Sciences, The Chinese University of Hong Kong, Hong Kong Eye Hospital, Kowloon, Hong Kong, People's Republic of China.
Insights
The pressure phosphene tonometer offers an acceptable method for measuring intraocular pressure (IOP) in children, showing close estimates and high specificity for elevated IOP. This tonometer is preferred by children over other methods, making it a viable alternative for IOP assessment.
Area of Science:
- Ophthalmology
- Pediatric Eye Care
- Ophthalmic Devices
Background:
- Accurate intraocular pressure (IOP) measurement is crucial for diagnosing and managing pediatric glaucoma.
- Traditional tonometry methods can be challenging in pediatric populations due to cooperation and comfort issues.
Purpose of the Study:
- To evaluate the accuracy and acceptability of the pressure phosphene tonometer (PPT) compared to non-contact tonometry (NCT) and Goldmann applanation tonometry (GAT) for IOP measurement in children.
- To assess pediatric patient comfort levels with different tonometry devices.
Main Methods:
- A prospective comparative study involving 50 children aged 5–14 years.
- IOP was measured using PPT, NCT, and GAT by masked examiners.
- Children rated their discomfort on a scale of 0 to 5.
Main Results:
- No statistically significant difference in mean IOP measurements was found between the three devices (P = .722).
- The pressure phosphene tonometer showed a mean difference of 2.9 mm Hg compared to Goldmann applanation tonometry.
- Children reported significantly less discomfort with the pressure phosphene tonometer (mean rating 0.6) compared to NCT (2.0) and GAT (2.3) (P < .001).
Conclusions:
- The pressure phosphene tonometer provides a reasonably accurate estimate of IOP in children and demonstrates high specificity for detecting elevated IOP.
- PPT measurement is significantly more acceptable and comfortable for pediatric patients.
- The pressure phosphene tonometer is a suitable alternative for IOP measurement in children.
Purpose:
To study the accuracy and acceptability of intraocular pressure (IOP) measurement by the pressure phosphene tonometer, non-contact tonometer, and Goldmann tonometer in children.
Methods:
Fifty children (5 to 14 years old) participated in this prospective comparative study. IOP was measured with the pressure phosphene tonometer, non-contact tonometer, and Goldmann tonometer by three different examiners who were masked to the results. The children were also asked to grade the degree of discomfort from 0 to 5 (0 = no discomfort; 5 = most discomfort).
Results:
The mean IOPs measured by the Goldmann tonometer, pressure phosphene tonometer, and non-contact tonometer were 15.9 mm Hg (standard deviation [SD]: = 5.5 mm Hg; range: 10 to 36 mm Hg), 16.0 mm Hg (SD: 2.9 mm Hg; range: 12 to 25 mm Hg), and 15.7 mm Hg (SD = 5.1 mm Hg; range: 8 to 32 mm Hg), respectively (P = .722). The mean difference between pressure phosphene tonometer and Goldmann tonometer readings was 2.9 mm Hg and that between non-contact tonometer and Goldmann tonometer readings was 2.1 mm Hg. The 95% confidence interval of the mean difference between pressure phosphene tonometer and Goldmann tonometer readings was -1.07 and 1.19, and that between non-contact tonometer and Goldmann tonometer readings was -1.07 and 0.53. The mean discomfort ratings for the pressure phosphene tonometer, non-contact tonometer, and Goldmann tonometer were 0.6, 2.0, and 2.3, respectively (P < .001).
Conclusion:
Although the pressure phosphene tonometer was less accurate than the non-contact tonometer compared with Goldmann tonometer, it gave a reasonably close estimate and had a high specificity of raised IOP. In addition, measurement by the pressure phosphene tonometer is most acceptable to children. The pressure phosphene tonometer can be considered as an alternative method of IOP measurement in children.
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