Objective: To compare the results of Proview pressure phosphene tonometry (PPPT) performed by the patient and an examiner with Goldmann applanation tonometry (GAT).
Methods: A comparative case series of 96 (192 eyes) consecutive patients from a glaucoma clinic was conducted. Intraocular pressure (IOP) was measured with GAT by one examiner, PPPT by another examiner, and PPPT by the patient. All examiners were masked to the results from any preceding IOP measurement.
Results: The coefficient of repeatability for repeated measurements for the GAT was +/-0.48 mmHg. The limits of agreement for self-measurement of IOP with the PPPT and examiner measured IOP with PPPT were 6.3 mmHg and 4.8 mmHg, respectively. The limits of agreement between GAT and self assessed PPPT were +/-11.8 mmHg (mean difference of 0.63 mmHg). When the same comparison was made between GAT and examiner assessed PPPT, the results were limits of agreement of +/-10 mmHg (mean difference of 2.86 mmHg). No significant difference was identified in the agreement of the GAT and the PPPT when subanalysed for age of patient or diagnosis (P > 0.05). The limits of agreement between self-assessed IOP with the PPPT and the GAT were +/-8.2 for those with IOP <20 mmHg and +/-14.9 mmHg for those with IOP>20 mmHg.
Conclusions: Poor agreement exists between IOP measured by GAT and PPPT measured by an examiner or by the patient.